Search results for: antimicrobial proteins

Authors: Bouchiha Hanene, Rouabhi Rachid, Bouchama Khaled, Djebar Berrebbah Houraya, Djebar Mohamed Reda

Abstract:

Recently, some natural products such as essentials oils (EOs) have been used in the fields as alternative to synthetic compounds, to minimize the negative impacts to the environment. This fact has led to questions about the possible impact of EOs on ecosystems. Currently in toxicology, the use of alternative models can help to understand the mechanisms of toxic action, at different levels of organization of ecosystems. Algae, protozoa and bacteria form the base of the food chain and protozoan cells are used as bioindicators often of pollution in environment. Unicellular organisms offer the possibility of direct study of independent cells with specific characteristics of individual cells and whole organisms at the same time. This unicellular facilitates the study of physiological processes, and effects of pollutants at the cellular level, which makes it widely used to assess the toxic effects of various xenobiotics. This study aimed to verify the effects of EOs of one famous plant used tremendously in our folk medicine, namely Artemisia herba alba in causing acute toxicity (24 hours) and chronic (15 days) toxicity for model cellular (Paramecium sp). To this end, cellular’s of paramecium were exposed to various concentrations (Three doses were chosen) of EOs extracted from plant (Artemisia herba alba). In the first experiment, the cellular s cultures were exposed for 48 hours to different concentrations to determine the median lethal concentration (DL50). We followed the evolution of physiological parameters (growth), biochemical (total proteins, respiratory metabolism), as well as the variations of a bio marker the GSH. Our results highlighted a light inhibition of the growth of the protozoa as well as a disturbance of the contents of total proteins and a reduction in the reduced rate of glutathione. The polarographic study revealed a stimulation of the consumption of O2 and this at the treated cells.

Keywords: essential oils, protozoa, bio indicators, toxicity, Growth, bio marker, proteins, polarographic

Procedia PDF Downloads 339

Authors: Anoff Anim, Lila A. M. Mahmoud, Maria Katsikogianni, Sanjit Nayak

Abstract:

Sustained and controlled delivery of antimicrobial drugs have been largely studied recently using metal organic frameworks (MOFs)and different polymers. However, much attention has not been given to combining both MOFs and biodegradable polymers, which would be a good strategy in providing a sustained gradual release of the drugs. Herein, we report a comparative study of the sustained and controlled release of widely used antibacterial drugs, cephalexin and metronidazole, from zinc-based MOF-5 incorporated in biodegradable polycaprolactone (PCL) and poly-lactic glycolic acid (PLGA) membranes. Cephalexin and metronidazole were separately incorporated in MOF-5 post-synthetically, followed by their integration into biodegradable PLGA and PCL membranes. The pristine MOF-5 and the loaded MOFs were thoroughly characterized by FT-IR, SEM, TGA and PXRD. Drug release studies were carried out to assess the release rate of the drugs in PBS and distilled water for up to 48 hours using UV-Vis Spectroscopy. Four bacterial strains from both the Gram-positive and Gram-negative types, Staphylococus aureus, Staphylococuss epidermidis, Escherichia coli, Acinetobacter baumanii, were tested against the pristine MOF, pure drugs, loaded MOFs and the drug-loaded MOF-polymer composites. Metronidazole-loaded MOF-5 composite of PLGA (PLGA-Met@MOF-5) was found to show highest efficiency to inhibit the growth of S. epidermidis compared to the other bacteria strains while maintaining a sustained minimum inhibitory concentration (MIC). This study demonstrates that the combination of biodegradable MOF-polymer composites can provide an efficient platform for sustained and controlled release of antimicrobial drugs and can be a potential strategy to integrate them in biomedical devices.

Keywords: antimicrobial resistance, biodegradable polymers, cephalexin, drug release metronidazole, MOF-5, PCL, PLGA

Procedia PDF Downloads 125

Authors: Ibrahim Sengor, Sumeyye Cesur, Ilyas Kartal, Faik Nuzhet Oktar, Nazmi Ekren, Ahmet Talat Inan, Oguzhan Gunduz

Abstract:

In recent years, many researchers focused on nano-size fiber production. Nanofibers have been studied due to their different and superior physical, chemical and mechanical properties. Poly (lactic acid) (PLA), is a type of biodegradable thermoplastic polyester derived from renewable sources used in biomedical owing to its biocompatibility and biodegradability. In addition, zinc oxide is an antibacterial material and hazelnut shell powder is a filling material. In this study, nanofibers were obtained by adding of different ratio Zinc oxide, (ZnO) and hazelnut shell powder at different concentration into Poly (lactic acid) (PLA) by using electrospinning method which is the most common method to obtain nanofibers. After dissolving the granulated polylactic acids in % 1,% 2,% 3 and% 4 with chloroform solvent, they are homogenized by adding tween and hazelnut shell powder at different ratios and then by electrospinning, nanofibers are obtained. Scanning electron microscope (SEM), Fourier transform infrared spectroscopy (FTIR), Differential scanning calorimeter (DSC) and physical analysis such as density, electrical conductivity, surface tension, viscosity measurement and antimicrobial test were carried out after production process. The resulting structures of the nanofiber possess antimicrobial and antiseptic properties, which are attractive for biomedical applications. The resulting structures of the nanofiber possess antimicrobial, non toxic, self-cleaning and rigid properties, which are attractive for biomedical applications.

Keywords: electrospinning, hazelnut shell powder, nanofibers, poly (lactic acid), zinc oxide

Procedia PDF Downloads 157

Authors: Hana Al-Baghaoi, Kumar Shiva Gubbiyappa, Mayuren Candasamy, Kiruthiga Perumal Vijayaraman

Abstract:

Acne is a chronic inflammatory disease of the sebaceous glands characterized by areas of skin with seborrhea, comedones, papules, pustules, nodules, and possibly scarring. Propionibacterium acnes (P. acnes), plays a key role in the pathogenesis of acne. Their colonization and proliferation trigger the host’s inflammatory response leading to the production of pro-inflammatory cytokines such as interleukin-8 (IL-8) and tumour necrosis factor-α (TNF-α). The usage of honey and natural compounds to treat skin ailments has strong support in the current trend of drug discovery. The present study was carried out evaluate antimicrobial and anti-inflammatory potential of Doani Sidr honey and its fractions against P. acnes and to screen madecassoside alone and in combination with fractions of honey. The broth dilution method was used to assess the antibacterial activity. Also, ultra structural changes in cell morphology were studied before and after exposure to Sidr honey using transmission electron microscopy (TEM). The three non-toxic concentrations of the samples were investigated for suppression of cytokines IL 8 and TNF α by testing the cell supernatants in the co-culture of the human peripheral blood mononuclear cells (hPBMCs) heat killed P. acnes using enzyme immunoassay kits (ELISA). Results obtained was evaluated by statistical analysis using Graph Pad Prism 5 software. The Doani Sidr honey and polysaccharide fractions were able to inhibit the growth of P. acnes with a noteworthy minimum inhibitory concentration (MIC) value of 18% (w/v) and 29% (w/v), respectively. The proximity of MIC and MBC values indicates that Doani Sidr honey had bactericidal effect against P. acnes which is confirmed by TEM analysis. TEM images of P. acnes after treatment with Doani Sidr honey showed completely physical membrane damage and lysis of cells; whereas non honey treated cells (control) did not show any damage. In addition, Doani Sidr honey and its fractions significantly inhibited (> 90%) of secretion of pro-inflammatory cytokines like TNF α and IL 8 by hPBMCs pretreated with heat-killed P. acnes. However, no significant inhibition was detected for madecassoside at its highest concentration tested. Our results suggested that Doani Sidr honey possesses both antimicrobial and anti-inflammatory effects against P. acnes and can possibly be used as therapeutic agents for acne. Furthermore, polysaccharide fraction derived from Doani Sidr honey showed potent inhibitory effect toward P. acnes. Hence, we hypothesize that fraction prepared from Sidr honey might be contributing to the antimicrobial and anti-inflammatory activity. Therefore, this polysaccharide fraction of Doani Sidr honey needs to be further explored and characterized for various phytochemicals which are contributing to antimicrobial and anti-inflammatory properties.

Keywords: Doani sidr honey, Propionibacterium acnes, IL-8, TNF alpha

Procedia PDF Downloads 385

Authors: Sulhee Lee, Geon Kim, Young-Seo Park

Abstract:

Unlike the traditional milk sterilization methods (LTLT, HTST, or UHT), pulsed electric field (PEF) technology is a non-thermal pasteurization process. This technology minimizes energy required for heat treatment in food processing, changes in sensory properties, and physical losses. In this study, structural changes of bovine milk proteins, the amount of immunoproteins such as IgG, and their storability by PEF treatment were examined. When the changes of protein content in PEF-treated milk were examined using HPLC, the amounts of α-casein and β-lactoglobulin were reduced over 40% each, whereas those of κ-casein and β-casein did not change. The amount of α-casein in HTST milk was reduced to 50%. When PEF was applied to milk at the energy level of 250 kJ, the amounts of IgG, IgA, β-lactoglobulin (β-LG), lactoferrin, and α-lactalbumin (α-LA) decreased by 43, 41, 35, 63, and 45%, respectively. When milk was sterilized by LTLT process followed by PEF process at the level of 150 kJ, the concentrations of IgG, IgA, β-LG, lactoferrin, and α-LA were 56.6, 10.6, 554, 2.8 and 660.1 μg/mL, respectively. When the bovine milk was sterilized by LTLT process followed by PEF process at the energy level of 180 kJ, storability of immunoproteins of milk was the highest and the concentrations of IgG, IgA, and β-LG decreased by 79.5, 6.5, and 134.5 μg/mL, respectively, when compared with the initial concentrations of those proteins. When bovine milk was stored at 4℃ after sterilization through HTST sterilizer followed by PEF process at the energy level of 200 kJ, the amount of lactoferrin decreased 7.3% after 36 days of storage, whereas that of lactoferrin of raw milk decreased 16.4%. Our results showed that PEF treatment did not change the protein structure nor induce protein denaturation in milk significantly when compared with LTLT or HTST sterilization. Also, LTLT or HTST process in combination with PEF were more effective than LTLT only or HTST only process in the conservation of immunoproteins in bovine milk.

Keywords: pulsed electric field, bovine milk, immunoproteins, sterilization

Procedia PDF Downloads 431

Authors: K. Karapetyan, F. Tkhruni, A. Aghajanyan, T. S. Balabekyan, L. Arstamyan

Abstract:

Introduction: Globalization of the food supply has created the conditions favorable for the emergence and spread of food-borne and especially dangerous pathogens (EDP) in developing countries. The fresh-cut fruit and vegetable industry is searching for alternatives to replace chemical treatments with biopreservative approaches that ensure the safety of the processed foods product. Antimicrobial compounds of lactic acid bacteria (LAB) possess bactericidal or bacteriostatic activity against intestinal pathogens, spoilage organisms and food-borne pathogens such as Listeria monocytogenes, Staphylococcus aureus and Salmonella. Endemic strains of LAB were isolated. The strains, showing broad spectrum of antimicrobial activity against food spoiling microorganisms, were selected. The genotyping by 16S rRNA sequencing, GS-PCR, RAPD PCR methods showed that they were presented by Lactobacillus rhamnosus109, L.plantarum 65, L.plantarum 66 and Enterococcus faecium 64 species. LAB are deposited in "Microbial Depository Center" (MDC) SPC "Armbiotechnology". Methods: LAB strains were isolated from different dairy products from rural households from the highland regions of Armenia. Serially diluted samples were spread on MRS (Merck, Germany) and hydrolyzed milk agar (1,2 % w/v). Single colonies from each LAB were individually inoculated in liquid MRS medium and incubated at 37oC for 24 hours. Culture broth with biomass was centrifuged at 10,000 g during 20 min for obtaining of cell free culture broth (CFC). The antimicrobial substances from CFC broth were purified by the combination of adsorption-desorption and ion-exchange chromatography methods. Separation of bacteriocins was performed using a HPLC method on "Avex ODS" C18 column. Mass analysis of peptides recorded on the device API 4000 in the electron ionization mode. The spot-on-lawn method on the test culture plated in the solid medium was applied. The antimicrobial activity is expressed in arbitrary units (AU/ml). Results. Purification of CFC broth of LAB allowed to obtain partially purified antimicrobial preparations which contains bacteriocins with broad spectrum of antimicrobial activity. Investigation of their main biochemical properties shown, that inhibitory activity of preparations is partially reduced after treatment with proteinase K, trypsin, pepsin, suggesting a proteinaceous nature of bacteriocin-like substances containing in CFC broth. Preparations preserved their activity after heat treatment (50-121 oC, 20 min) and were stable in the pH range 3–8. The results of SDS PAAG electrophoresis show that L.plantarum 66 and Ent.faecium 64 strains have one bacteriocin (BCN) with maximal antimicrobial activity with approximate molecular weight 2.0-3.0 kDa. From L.rhamnosus 109 two BCNs were obtained. Mass spectral analysis indicates that these bacteriocins have peptide bonds and molecular weight of BCN 1 and BCN 2 are approximately 1.5 kDa and 700 Da. Discussion: Thus, our experimental data shown, that isolated endemic strains of LAB are able to produce bacteriocins with high and different inhibitory activity against broad spectrum of microorganisms of different taxonomic group, such as Salmonella sp., Esherichia coli, Bacillus sp., L.monocytogenes, Proteus mirabilis, Staph. aureus, Ps. aeruginosa. Obtained results proved the perspectives for use of endemic strains in the preservation of foodstuffs. Acknowledgments: This work was realized with financial support of the Project Global Initiatives for Preliferation Prevention (GIPP) T2- 298, ISTC A-1866.

Keywords: antimicrobial activity, bacteriocins, endemic strains, food safety

Procedia PDF Downloads 550

Authors: Afifa Hafidh, Hedia Chaabane

Abstract:

This work mainly focused on the synthetic strategies and biological activities associated with pyrazoles. Pyrazole derivatives have been successfully synthesized by simple and facile method and studied for their antibacterial activity. These compounds were prepared from pyrazolic difunctional compounds as starting materials, by reaction with salicylic acid, paracetamol and thiosemicarbazide respectively. Structure of all the prepared compounds confirmation were proved using (FT-IR), (1H-NMR) and (13C-NMR) spectra in addition to melting points. The screening of the antimicrobial activity of the pyrazolic derivatives was examined against different microorganisms in the present study. They were screened for their antimicrobial activities against gram positive bacteria, gram negative bacteria and Candida albicans. The synthesized compounds were found to exhibit high antibacterial and antifungal efficiency against several tested bacterial strains, using agar diffusion method and filter paper disc-diffusion method. Ampicillin was used as positive control for all strains except Candida albicans for which Nystatin was used. The obtained results reveal that the antibacterial activity of some pyrazolic derivatives is comparable to that observed for the control samples (Ampicilin and Nystatin), suggesting a strong antibacterial activity. The analysis of these results shows that synthesized products react on the surfaces cell walls that are disrupted. When these products are in contact with the bacteria, they damage the membrane, leading to the perturbation of different cellular processes and then leakage of cytoplasm, resulting in the death of the cells. The results will be presented in details. The obtained products constitute effective antibacterial agents and important compounds for biological systems.

Keywords: salicylic acid, antimicrobial activities, antioxidant activity, paracetamol, pyrazole, thiosemicarbazide

Procedia PDF Downloads 165

Authors: M. Rehan, H. Mashaly, H. Emam, A. Abou El-Kheir, S. Mowafi

Abstract:

In this work, we will study a simple highly efficient technique to impart multi functional properties to different fabric substrates by in situ Ag NPs incorporation into fabric matrix. Ag NPs as a coloration and antimicrobial agent were prepared in situ incorporation into fabric matrix (Cotton and Wool) by using trisodium citrate as reducing and stabilizing agent. The Ag NPs treated fabric (Cotton and Wool) showed different color because of localized surface Plasmon resonance (LSPR) property of Ag NPs. The formation of Ag NPs was confirmed by UV/Vis spectra for the supernatant solutions and The Ag NPs treated fabric (Cotton and Wool) were characterized by scanning electron microscopy (SEM) and X-ray photo electron spectroscopy (XPS). The dependence of color properties characterized by colorimetric, fastness and antibacterial properties evaluated by Escherichia coli using counting method and the reaction parameters were studied. The results indicate that, the in situ Ag NPs incorporation into fabric matrix approach can simultaneously impart colorant and antimicrobial properties into different fabric substrates.

Keywords: Ag NPs, coloration, antibacterial, wool, cotton fabric

Procedia PDF Downloads 348

Authors: Lok Bahadur Shrestha, Narayan Raj Bhattarai, Basudha Khanal

Abstract:

Introduction: Coagulase-negative staphylococci (CoNS) are the normal commensal of human skin and mucous membranes. The study was carried out to study the prevalence of CoNS among clinical isolates, to characterize them up to species level and to compare the three conventional methods for detection of biofilm formation. Objectives: to characterize the clinically significant coagulase-negative staphylococci up to species level, to compare the three phenotypic methods for the detection of biofilm formation and to study the antimicrobial susceptibility pattern of the isolates. Methods: CoNS isolates were obtained from various clinical samples during the period of 1 year. Characterization up to species level was done using biochemical test and study of biofilm formation was done by tube adherence, congo red agar, and tissue culture plate method. Results: Among 71 CoNS isolates, seven species were identified. S. epidermidis was the most common species followed by S. saprophyticus, S. haemolyticus. Antimicrobial susceptibility pattern of CoNS documented resistance of 90% to ampicillin. Resistance to cefoxitin and ceftriaxone was observed in 55% of the isolates. We detected biofilm formation in 71.8% of isolates. The sensitivity of tube adherence method was 82% while that of congo red agar method was 78%. Conclusion: Among 71 CoNS isolated, S. epidermidis was the most common isolates followed by S. saprophyticus and S. haemolyticus. Biofilm formation was detected in 71.8% of the isolates. All of the methods were effective at detecting biofilm-producing CoNS strains. Biofilm former strains are more resistant to antibiotics as compared to biofilm non-formers.

Keywords: CoNS, congo red agar, bloodstream infections, foreign body-related infections, tissue culture plate

Procedia PDF Downloads 188

Authors: Qing Cao, Fei Wang, Yu-Qiang Wang, Li-Ya Huang, Tian-Tian Sang, Shu-Yan Chen

Abstract:

Aims: TNF Receptor-Associated Factor 6 (TRAF6) acts as a multifunctional regulator of the Transforming Growth Factor (TGF)-β signaling pathway, and mediates Smad-independent JNK and p38 activation via TGF-β. This study was performed to test the hypothesis that TGF-β/TRAF6 is essential for angiotensin-II (Ang II)-induced differentiation of rat c-kit+ Cardiac Stem Cells (CSCs). Methods and Results: c-kit+ CSCs were isolated from neonatal Sprague Dawley (SD) rats, and their c-kit status was confirmed with immunofluorescence staining. A TGF-β type I receptor inhibitor (SB431542) or the small interfering RNA (siRNA)-mediated knockdown of TRAF6 were used to investigate the role of TRAF6 in TGF-β signaling. Rescue of TRAF6 siRNA transfected cells with a 3'UTR deleted siRNA insensitive construct was conducted to rule out the off target effects of the siRNA. TRAF6 dominant negative (TRAF6DN) vector was constructed and used to infect c-kit+ CSCs, and western blotting was used to assess the expression of TRAF6, JNK, p38, cardiac-specific proteins, and Wnt signaling proteins. Physical interactions between TRAF6 and TGFβ receptors were studied by coimmunoprecipitation. Cardiac differentiation was suppressed in the absence of TRAF6. Forced expression of TRAF6 enhanced the expression of TGF-β-activated kinase1 (TAK1), and inhibited Wnt signaling. Furthermore, TRAF6 increased the expression of cardiac-specific proteins (cTnT and Cx-43) but inhibited the expression of Wnt3a. Conclusions: Our data suggest that TRAF6 plays an important role in Ang II induced differentiation of c-kit+ CSCs via the non-canonical signaling pathway.

Keywords: cardiac stem cells, differentiation, TGF-β, TRAF6, ubiquitination, Wnt

Procedia PDF Downloads 390

Authors: Harika Atmaca, Emir Bozkurt, Latife Merve Oktay, Selim Uzunoglu, Ruchan Uslu, Burçak Karaca

Abstract:

Microarrays have been developed for highly parallel enzyme-linked immunosorbent assay (ELISA) applications. The most common protein arrays are produced by using multiple monoclonal antibodies, since they are robust molecules which can be easily handled and immobilized by standard procedures without loss of activity. Protein expression profiling with protein array technology allows simultaneous analysis of the protein expression pattern of a large number of proteins. Trabectedin, a tetrahydroisoquinoline alkaloid derived from a Caribbean tunicate, Ecteinascidia turbinata, has been shown to have antitumor effects. Here, we used a novel proteomic approach to explore the mechanism of action of trabectedin in prostate cancer cell line PC-3 by apoptosis antibody microarray. XTT cell proliferation kit and Cell Death Detection Elisa Plus Kit (Roche) was used for measuring cytotoxicity and apoptosis. Human Apoptosis Protein Array (R&D Systems) which consists of 35 apoptosis related proteins was used to assess the omic protein expression pattern. Trabectedin induced cytotoxicity and apoptosis in prostate cancer cells in a time and concentration-dependent manner. The expression levels of the death receptor pathway molecules, TRAIL-R1/DR4, TRAIL R2/DR5, TNF R1/TNFRSF1A, FADD were significantly increased by 4.0-, 21.0-, 4.20- and 11.5-fold by trabectedin treatment in PC-3 cells. Moreover, mitochondrial pathway related pro-apoptotic proteins Bax, Bad, Cytochrome c, and Cleaved Caspase-3 expressions were induced by 2.68-, 2.07-, 2.8-, and 4.5-fold and the expression levels of anti-apoptotic proteins Bcl-2 and Bcl-XL were reduced by 3.5- and 5.2-fold in PC-3 cells. Proteomic (antibody microarray) analysis suggests that the mechanism of action of trabectedin may be exerted via the induction of both intrinsic and extrinsic apoptotic pathways. The antibody microarray platform can be utilised to explore the molecular mechanism of action of novel anticancer agents.

Keywords: trabectedin, prostate cancer, omic protein expression profile, apoptosis

Procedia PDF Downloads 438

Authors: Michail Milas, Aikaterini Dafni Tegiou, Nickolas Rigopoulos, Eustathios Giaouris, Zaharias Loannou

Abstract:

Nanotechnology, a relatively new scientific field, addresses the manipulation of nanoscale materials and devices, which are governed by unique properties, and is applied in a wide range of industries, including food packaging. The incorporation of nanoparticles into polymer matrices used for food packaging is a field that is highly researched today. One such combination is silver nanoparticles with polypropylene. In the present study, the synthesis of the silver nanoparticles was carried out by a natural method. In particular, a ripe banana peel extract was used. This method is superior to others as it stands out for its environmental friendliness, high efficiency and low-cost requirement. In particular, a 1.75 mM AgNO₃ silver nitrate solution was used, as well as a BPE concentration of 1.7% v/v, an incubation period of 48 hours at 70°C and a pH of 4.3 and after its preparation, the polypropylene films were soaked in it. For the PP films, random PP spheres were melted at 170-190°C into molds with 0.8cm diameter. This polymer was chosen as it is suitable for plastic parts and reusable plastic containers of various types that are intended to come into contact with food without compromising its quality and safety. The antimicrobial test against Escherichia coli DFSNB1 and Staphylococcus epidermidis DFSNB4 was performed on the films. It appeared that the films with silver nanoparticles had a reduction, at least 100 times, compared to those without silver nanoparticles, in both strains. The limit of detection is the lower limit of the vertical error lines in the presence of nanoparticles, which is 3.11. The main reasons that led to the adsorption of nanoparticles are the porous nature of polypropylene and the adsorption capacity of nanoparticles on the surface of the films due to hydrophobic-hydrophilic forces. The most significant parameters that contributed to the results of the experiment include the following: the stage of ripening of the banana during the preparation of the plant extract, the temperature and residence time of the nanoparticle solution in the oven, the residence time of the polypropylene films in the nanoparticle solution, the number of nanoparticles inoculated on the films and, finally, the time these stayed in the refrigerator so that they could dry and be ready for antimicrobial treatment.

Keywords: antimicrobial control, banana peel extract, E. coli, natural synthesis, microbe, plant extract, polypropylene films, S.epidermidis, silver nano, random pp

Procedia PDF Downloads 162

Authors: Feleke Terefe Fanta

Abstract:

The existence of heavy metals and microbial contaminants in aquatic system of Akaki river basin, a sub city of Addis Ababa, has become a public concern as human population increases and land development continues. This is because effluents from chemical and pharmaceutical industries are directly discharged onto surrounding land, irrigation fields and surface water bodies. In the present study, we synthesised zeolites and copper- zeolite composite based adsorbent through cost effective and simple approach to mitigate the problem. The study presents determination of heavy metal content and microbial contamination level of waste water sample collected from Akaki river using zeolites and copper- doped zeolites as adsorbents. The synthesis of copper- zeolite X composite was carried out by ion exchange method of copper ions into zeolites frameworks. The optimum amount of copper ions loaded into the zeolites frameworks were studied using the pore size determination concept via iodine test. The copper- loaded zeolites were characterized by X-ray diffraction (XRD). The XRD analysis showed clear difference in phase purity of zeolite before and after copper ion exchange. The concentration of Cd, Cr, and Pb were determined in waste water sample using atomic absorption spectrophotometry. The mean concentrations of Cd, Cr, and Pb in untreated sample were 0.795, 0.654 and 0.7025 mg/L respectively. The concentration of Cd, Cr, and Pb decreased to 0.005, 0.052 and BDL mg/L for sample treated with bare zeolite X while a further decrease in concentration of Cd, Cr, and Pb (0.005, BDL and BDL) mg/L respectively was observed for the sample treated with copper- zeolite composite. The antimicrobial activity was investigated by exposing the total coliform to the Zeolite X and Copper-modified Zeolite X. Zeolite X and Copper-modified Zeolite X showed complete elimination of microbilas after 90 and 50 minutes contact time respectively. This demonstrates effectiveness of copper- zeolite composite as efficient disinfectant. To understand the mode of heavy metals removal and antimicrobial activity of the copper-loaded zeolites; the adsorbent dose, contact time, temperature was studied. Overall, the results obtained in this study showed high antimicrobial disinfection and heavy metal removal efficiencies of the synthesized adsorbent.

Keywords: waste water, copper doped zeolite x, adsorption heavy metal, disinfection

Procedia PDF Downloads 67

Authors: Fatemeh Moradian, Razieh Ghorbani, Poria Biparva

Abstract:

Growing resistance of microorganisms to potent antibiotics has renewed a great interest towards investigating bactericidal properties of nanoparticles and their Nano composites as an alternative. The use of metal nanoparticles to combat bacterial infections is one of the most wide spread applications of nanotechnology in the field of antibacterial. Nanomaterials have unique properties compared to their bulk counterparts. In this report, we demonstrate the antimicrobial activity of zerovalent Iron(ZVI) and Ag(silver) nanoparticles against Gram-negative bacteria E.coli(DH5α) and Pseudomonas aeruginosa. At first ZVI and Ag nanoparticles were synthesized by chemical reduction method and using scanning electron microscopy (SEM) the nanoparticle size determined. Different concentrations of Ag and ZVI nanoparticles were added to bacteria on nutrient agar medium. Minimum inhibitory concentration (MIC) of Ag and Fe nanoparticles for P. aeruginosa were 5µM and 1µg as well as for E.coli were 6µM. and 10 µg, respectively. Among the two nanoparticles, ZVI showed that the greatest antimicrobial activity against E.coli and Ag nanoparticle on P.aeruginosa. Results suggested that the bactericidal effect of metal nanoparticles has been attributed to their small size as well as high surface to volume ratio and NPs could be used as an effective antibacterial material.

Keywords: bactericidal properties, MIC, nanoparticle, SEM

Procedia PDF Downloads 584

Authors: Pampita Chakraborty, Sukumar Mukherjee

Abstract:

Diabetes Mellitus (DM) is commonly encountered metabolic disorder in clinical practice. An estimated 25 percent of DM patients develop foot problems. Foot ulceration and infection are one of the major causes of morbidity, hospitalization or even amputation. Objective: To isolate and identify bacterial pathogens in Diabetic Foot Ulcer (DFU) and to observe its antimicrobial sensitivity pattern. Methodology: A prospective study was conducted for a period of 9 months at the Department of Microbiology, GD Hospital & Diabetes Institute, Kolkata. 75 DFU patients were recruited in the study. Specimens for microbiological studies obtained from ulcer base were examined as gram stained smear and was cultured aerobically on Nutrient agar, Blood agar and MacConkey agar plates. Antimicrobial sensitivity test was performed by disc diffusion techniques according to CLSI guidelines. Result: In this study out of 75cases, 73% (55/75) were male and 27% (20/75) were females with mean (SD) age of 51.11(±10) years. Out of 75 pus cultures, 63(84%) showed growth of microorganism making total of 81 bacterial isolates with 71.42% of monomicrobial infection and 28.57% of polymicrobial infection. Out of 81 isolates 53(65.43%) were gram negative and 21(25.92%) were gram positive. E.coli was relatively common isolate 21(26%) followed by Staphylococcus aureus 15(18.5%), Klebsiella pneumonia 14(17.28%), Pseudomonas aeruginosa 12 (14.81%), Proteus spp. 3 (3.70%), and Enterococcus faecalis 6 (7.40%). 75% of Gram-negative microorganism were extended Beta-lactamase enzyme (ESBL) producer and around 20 % of Klebsiella and Proteus spp. were carbapenemase enzyme producer. Among Gram positive, around 50% of S.aureus was MRSA, sensitive only to Vancomycin, Teicoplanin & Linezolid. Conclusion: More prevalence of monomicrobial gram-negative bacteria than gram-positive bacteria in DFU was observed. This study emphasizes that Beta-Lactam group of antibiotics should not be the empirical treatment of choice for Gram-negative isolates; instead alternatives like Carbapenems, Amikacin could be a better option. On the other hand, Vancomycin and Linezolid are preferred for most of the infection with gram-positive aerobes. Continuous surveillance of resistant bacteria is required for empiric therapy.

Keywords: antibiotic resistant, antimicrobial susceptibility, diabetic foot ulcer, surveillance

Procedia PDF Downloads 353

Authors: Howaida I. Abd-Alla, Amal Z. Hassan, Maha Soltan, Atef G. Hanna, Mounir M. El-Safty

Abstract:

Acokanthera oblongifolia (Apocynaceae) is used for treatment of several infection diseases and is a well-known cardiac glycoside-containing plant. The infusion of their leaves is gargled to treat tonsillitis and is used medicinally to treat snakebites. The total cardiac glycosides content in the leaves was determined by referring to gitoxigenin as a reference compound. Two triterpenes, lup-20(29)-en-3β-ol (1) and oleanolic acid (2); two cardenolides, acovenoside A (3) and acobioside A (4) were isolated from the ethyl acetate extract. Their structures were determined on the basis of spectral analysis. Major constituents isolated from this species were evaluated for cytotoxicity against normal lung cell line (Wi38) and antimicrobial activities against Gram-positive (two strains) and Gram-negative bacteria (four strains), yeast-like fungi (two strains) and fungi (five strains). The minimum inhibitory concentration (MIC) of the compounds was determined using broth microdilution method. Their viral inhibitory effects against avian influenza virus type A (AI-H5N1) and Newcastle disease virus (NDV) in specific pathogen free (SPF) embryonated chicken eggs (ECE), chicken embryo fibroblasts (CEF) and Vero cells were evaluated. The cardenolide (3) showed viral inhibitory effects against AI-H5N1 and NDV in SPF ECE. The two cardenolides isolated have shown potent cytotoxicity against Vero cells. Compound (3) showed potent anti-Gram-negative bacteria activity. These results suggested that acovenoside A might be promising for future antiviral and antimicrobial drug design.

Keywords: Acokanthera, AI-H5N1, Cardenolides, NDV, SPF-ECE, VERO, Wi38 , Microbe

Procedia PDF Downloads 161

Authors: Sahar Essa, Hussain A. Safar, Raj Raghupathy

Abstract:

Human cytomegalovirus (CMV) continues to be a source of severe complications in immunologically immature and immunocompromised hosts. Effective CMV vaccines that help diminish CMV disease in transplant patients and avoid congenital infection are of great importance. Though the exact roles of defense mechanisms are unidentified, viral-specific antibodies and cytokine responses are known to be involved in controlling CMV infections. CMV envelope glycoprotein B (UL55/gB), matrix proteins (UL83/pp65, UL99/pp28, UL32/pp150), and assembly protein UL80a/pp38 are known to be targets of antiviral immune responses. We immunized mice intraperitoneally with these five CMV-related proteins (commercial) for their ability to induce specific antibody responses (in-house immunoassay) and cytokine production (commercial assay) in a mouse model. We observed a significant CMV-antigen-specific antibody response to pp38 and pp65 (E/C ˃2.0, p˂0.001). Mice immunized with pp38 had significantly higher concentrations of GM-CSF, IFN-α, IL-2 IL-4, IL-5, and IL-17A (p˂0.05). Mice immunized with pp65 showed significantly higher concentrations of GM-CSF, IFN-γ, IL-2 IL-4, IL-10, IL-12, IL-17A, and TNF-α. Th1 to Th2 cytokines ratios revealed a Th1 cytokine bias in mice immunized with pp38, pp65, pp150, and gB. We suggest that stimulation with multiple CMV-related proteins, which include pp38, pp65, and gB antigens, will allow both humoral and cellular immune responses to be efficiently activated, thus serving as appropriate CMV antigens for future vaccines.

Keywords: cytomegalovirus, UL99/pp28, UL80a/pp38, UL83/pp65, UL32/pp150, UL55/gB, CMV-antigen-specific antibody, CMV antigen-specific cytokine responses

Procedia PDF Downloads 72

Authors: Andrés Lara Guillén, José M. Soriano Disla, Gemma Castejón Martínez, David Fernández-Gutiérrez

Abstract:

The worldwide population is exponentially increasing, which causes a rising demand for food, energy and non-renewable resources. These demands must be attended to from a circular economy point of view. Under this approach, the obtention of strategic products from biowaste is crucial for the society to keep the current lifestyle reducing the environmental and social issues linked to the lineal economy. This is the main objective of the VALUEWASTE project. VALUEWASTE is about valorizing urban biowaste into proteins for food and feed and biofertilizers, closing the loop of this waste stream. In order to achieve this objective, the project validates three value chains, which begin with the anaerobic digestion of the biowaste. From the anaerobic digestion, three by-products are obtained: i) methane that is used by microorganisms, which will be transformed into microbial proteins; ii) digestate that is used by black soldier fly, producing insect proteins; and iii) a nutrient-rich effluent, which will be transformed into biofertilizers. VALUEWASTE is an innovative solution, which combines different technologies to valorize entirely the biowaste. However, it is also required to demonstrate that the solution is greener than other traditional technologies (baseline systems). On one hand, the proteins from microorganisms and insects will be compared with other reference protein production systems (gluten, whey and soybean). On the other hand, the biofertilizers will be compared to the production of mineral fertilizers (ammonium sulphate and synthetic struvite). Therefore, the aim of this study is to provide that biowaste valorization can reduce the environmental impacts linked to both traditional proteins manufacturing processes and mineral fertilizers, not only at a pilot-scale but also at an industrial one. In the present study, both baseline system and VALUEWASTE solution are evaluated through the Environmental Life Cycle Assessment (E-LCA). The E-LCA is based on the standards ISO 14040 and 14044. The Environmental Footprint methodology was the one used in this study to evaluate the environmental impacts. The results for the baseline cases show that the food proteins coming from whey have the highest environmental impact on ecosystems compared to the other proteins sources: 7.5 and 15.9 folds higher than soybean and gluten, respectively. Comparing feed soybean and gluten, soybean has an environmental impact on human health 195.1 folds higher. In the case of biofertilizers, synthetic struvite has higher impacts than ammonium sulfate: 15.3 (ecosystems) and 11.8 (human health) fold, respectively. The results shown in the present study will be used as a reference to demonstrate the better environmental performance of the bio-based products obtained through the VALUEWASTE solution. Other originalities that the E-LCA performed in the VALUEWASTE project provides are the diverse direct implications on investment and policies. On one hand, better environmental performance will serve to remove the barriers linked to these kinds of technologies, boosting the investment that is backed by the E-LCA. On the other hand, it will be a germ to design new policies fostering these types of solutions to achieve two of the key targets of the European Community: being self-sustainable and carbon neutral.

Keywords: anaerobic digestion, biofertilizers, circular economy, nutrients recovery

Procedia PDF Downloads 84

Authors: Phanwipa Pangsri, Yawariyah Weahayee

Abstract:

The lactic acid bacteria (LAB) were isolated from 10 samples of fermented foods (Sa-tor-dong and Bodo) in South locality of Thailand. The 23 isolates of lactic acid bacteria were selected, which were exhibited a clear zone and growth on MRS agar supplemented with CaCO3. All of lactic acid bacteria were tested on morphological and biochemical. The result showed that all isolates were Gram’s positive, non-spore forming but only 10 isolates displayed catalase negative. The 10 isolates including BD 1.1, BD 1.2, BD 2.1, BD2.2, BD 2.3, BD 3.1, BD 4.1, BD 5.2, ST4.1, and ST 5.2 were selected for inhibition activity determination. Only 2 strains (ST 4.1 and BD 2.3) showed inhibition zone on agar, when using Escherichia coli sp. as target strain. The ST 4.1 showed highest inhibition zone on agar, which was selected for probiotic property testing. The ST4.1 isolate could grow in MRS broth containing a high concentration of sodium chloride 6%, bile salts 7%, pH 4-10 and vary temperature at 15-45^oC.

Keywords: lactic acid bacteria, probiotic, antimicrobial, probiotic property testing

Procedia PDF Downloads 369

Authors: A. K. Tursunova, O. V. Chebonenko, A. Zh. Amirkulova, A. O. Abaildayev, O. A. Sapko, Y. M. Dyo, A. Sh. Utarbaeva

Abstract:

Fusarium solani and its variants cause root and stem rot of plants. Dry rot is the most common disease of potato tubers during storage. The causative agents of fusariosis in contact with plants behave as antagonists, growth stimulants or parasites. The diversity of host-parasite relationships is explained by the parasite’s ability to produce a wide spectrum of biologically active compounds including toxins, enzymes, oligosaccharides, antibiotic substances, enniatins and gibberellins. Many of these metabolites contribute to the creation of compatible relations; others behave as elicitors, inducing various protective responses in plants. An important part of the strategy for developing plant resistance against pathogens is the activation of protein synthesis to produce protective ‘pathogenesis-related’ proteins. The family of PR-proteins known to confer the most protective response is chitinases (EC 3.2.1.14, Cht) and β-1,3-glucanases (EC 3.2.1.39, Glu). PR-proteins also include a large multigene family of peroxidases (EC 1.11.1.7, Pod), and increased activity of Pod and expression of the Pod genes leads to the development of resistance to a broad class of pathogens. Despite intensive research on the role of PR-proteins, the question of their participation in the mechanisms of formation of the F.solani–S.tuberosum pathosуstem is not sufficiently studied. Our aim was to investigate the effect of different classes of F. solani metabolites on the activity of chitinase, β-1,3-glucanases and peroxidases in tubers of Solanum tuberosum. Metabolite culture filtrate (CF) and cytoplasmic components were fractionated by extraction of the mycelium with organic solvents, salting out techniques, dialysis, column chromatography and ultrafiltration. Protein, lipid, carbohydrate and polyphenolic fractions of fungal metabolites were derived. Using enzymatic hydrolysis we obtained oligo glycans from fungal cell walls with different molecular weights. The activity of the metabolites was tested using potato tuber discs (d = 16mm, h = 5mm). The activity of PR-proteins of tubers was analyzed in a time course of 2–24 hours. The involvement of the analysed metabolites in the modulation of both early non-specific and late related to pathogenesis reactions was demonstrated. The most effective inducer was isolated from the CF (fraction of total phenolic compounds including naphtazarins). Induction of PR-activity by this fraction was: chitinase - 340-360%, glucanase - 435-450%, soluble forms of peroxidase - 400-560%, related forms of peroxidase - 215-237%. High-inducing activity was observed by the chloroform and acetonitrile extracts of the mycelium (induction of chitinase and glucanase activity was 176-240%, of soluble and bound forms of peroxidase - 190-400%). The fraction of oligo glycans mycelium cell walls of 1.2 kDa induced chitinase and β-1,3-glucanase to 239-320%; soluble forms and related peroxidase to 198-426%. Oligo glycans cell walls of 5-10 kDa had a weak suppressor effect - chitinase (21-25%) and glucanase (25-28%) activity; had no effect on soluble forms of peroxidase, but induced to 250-270% activity related forms. The CF polysaccharides of 8.5 kDa and 3.1 kDa inhibited synchronously the glucanase and chitinase specific response in step (after 24 hours at 42-50%) and the step response induced nonspecific peroxidase activity: soluble forms 4.8 -5.2 times, associated forms 1.4-1.6 times.

Keywords: fusarium solani, PR-proteins, peroxidase, solanum tuberosum

Procedia PDF Downloads 196

Authors: Yuen Yee Li Sip, Lei Zhai

Abstract:

Biofilms are formed by the attachment of microorganisms onto substrates via self-synthesized extracellular polymeric substances. They have been observed in the International Space Stations (ISS), in which biofilms can jeopardize the performance of key equipment and can pose health threats to the astronauts. This project aims at building conformal nanoporous surfaces that are infused with lubricant and decorated with antimicrobial nanoparticles while simultaneously evaluating their efficacy in preventing biofilm formation. Lubricant-impregnated surfaces (LIS) are fabricated by using a layer-by-layer assembly of silica nanoparticles to generate conformal nanoporous coatings on substrates and fill the films with fluorinated fluids. LIS has demonstrated excellent repellency to a broad range of liquids, preventing microbe adhesion (anti-biofouling). Silver or copper nanoparticles were deposited on the coatings prior to lubricant infusion in order to provide antimicrobial characteristics to the coating. Surface morphology and biofilm growth were characterized to understand how the coating morphology affects the LIS stability and anti-biofouling behaviors (stationary and in a flow).

Keywords: biofilm, coatings, nanoporous, antifouling

Procedia PDF Downloads 91

Authors: Imana Shahrin Tania, Mohammad Ali

Abstract:

The present study reports the synthesis, characterization and application of nano-sized zinc-oxide (ZnO) particles on a cotton fabric surface. The aim of the investigations is to impart the antimicrobial activity on textile cloth. Nanoparticle is synthesized by wet chemical method from zinc sulphate and sodium hydroxide. SEM (scanning electron micrograph) images are taken to demonstrate the surface morphology of nanoparticles. XRD analysis is done to determine the crystal size of the nanoparticle. With the conformation of nanoformation, the cotton woven fabric is treated with ZnO nanoparticle by mechanical thermo-fixation (pad-dry-cure) technique. To increase the wash durability of nano treated fabric, an acrylic binder is used as a fixing agent. The treated fabric shows up to 90% bacterial reduction for S. aureus (Staphylococcus aureus) and 87% for E. coli (Escherichia coli) which is appreciable for bacteria protective clothing.

Keywords: nanoparticle, zinc oxide, cotton fabric, antibacterial activity, binder

Procedia PDF Downloads 125

Authors: Callistus I. Iheme, Kenneth E. Asika, Emmanuel I. Ugwor, Chukwuka U. Ogbonna, Ugonna H. Uzoka, Nneamaka A. Chiegboka, Chinwe S. Alisi, Obinna S. Nwabueze, Amanda U. Ezirim, Judeanthony N. Ogbulie

Abstract:

Antimicrobial resistance (AMR) is a major threat to the global health sector. Zinc oxide nanocomposites (ZnONCs), composed of zinc oxide nanoparticles and phytochemicals from Azadirachta indica aqueous leaf extract, were assessed for their physico-chemicals, in silico and in vitro antimicrobial properties on multidrug-resistant Escherichia coli enzymes. Gas chromatography coupled with mass spectroscope (GC-MS) analysis on the ZnONCs revealed the presence of twenty volatile phytochemical compounds, among which is scoparone. Characterization of the ZnONCs was done using ultraviolet-visible spectroscopy (UV-vis), energy dispersive spectroscopy (EDX), transmission electron microscopy (TEM), scanning electron microscopy (SEM), and x-ray diffractometer (XRD). Dehydrogenase enzyme converts colorless 2,3,5-triphenyltetrazolium chloride to the red triphenyl formazan (TPF). The rate of formazan formation in the presence of ZnONCs is proportional to the enzyme activities. The color formation is extracted and determined at 500 nm, and the percentage of enzyme activity is calculated. To determine the bioactive components of the ZnONCs, characterize their binding to enzymes, and evaluate the enzyme-ligand complex stability, respectively Discrete Fourier Transform (DFT) analysis, docking, and molecular dynamics simulations will be employed. The results showed arrays of ZnONCs nanorods with maximal absorption wavelengths of 320 nm and 350 nm and thermally stable at the temperature range of 423.77 to 889.69 ℃. In vitro study assessed the dehydrogenase inhibitory properties of the ZnONCs, conjugate of ZnONCs and ampicillin (ZnONCs-amp), the aqueous leaf extract of A. indica, and ampicillin (standard drug). The findings revealed that at the concentration of 500 μm/mL, 57.89 % of the enzyme activities were inhibited by ZnONCs compared to 33.33% and 21.05% of the standard drug (Ampicillin), and the aqueous leaf extract of the A. indica respectively. The inhibition of the enzyme activities by the ZnONCs at 500 μm/mL was further enhanced to 89.74 % by conjugating with Ampicillin. In silico study on the ZnONCs revealed scoparone as the most viable competitor of nicotinamide adenine dinucleotide (NAD⁺) for the coenzyme binding pocket on E. coli malate and histidinol dehydrogenase. From the findings, it can be concluded that the scoparone components of the nanocomposites in synergy with the zinc oxide nanoparticles inhibited E. coli malate and histidinol dehydrogenase by competitively binding to the NAD⁺ pocket and that the conjugation of the ZnONCs with ampicillin further enhanced the antimicrobial efficiency of the nanocomposite against multidrug resistant E. coli.

Keywords: antimicrobial resistance, dehydrogenase activities, E. coli, zinc oxide nanocomposites

Procedia PDF Downloads 25

Authors: Benyoucef Amel, Benmechernene Zineb, Kihal Mebrouk

Abstract:

One strain (V1) of Leuconostoc mesonteroides was isolated from goat’s milk collected from El Bayadh which is located in the west of Algeria and was characterized by phenotypic and biochemical methods. This strain was tested for their antimicrobial activity against indicator bacteria (Staphylococcus aureus ATCC 43300, Listeria innocua ATCC 33090, Listeria ivanovii ATCC 19119) and was evaluated for certain properties relevant to probiotic including acid resistance (pH 2 ; 3and 4), bile tolerance at 0.5%, 1% and 2%, pepsin resistance 3mg/ml at pH 2 and 3, hemolytic activity and antibiotics sensitivity. Our results revealed the strain V1 showed antagonistic activity against Staphylococcus aureus, Listeria innocua and Listeria ivanovii, due to a production of proteinous nature substances. The strain was resistant to pH 3 and 4, bile salts at 0.5%, 1% and 2% and pepsin at pH 3; and was γ-hemolytic and susceptible to four antibiotics: Chloramphenicol, pristinamycin, Clindamycin and Lincomycin. These results may be considered the strain V1 as suitable probiotic candidate.

Keywords: antimicrobial, goat‘s milk, Leuconostoc, probiotic

Procedia PDF Downloads 237

Authors: Amanda Cristina de Oliveira, Elias de Souza Monteiro Filho, Roberta Ceriani

Abstract:

Liquid-liquid extraction in aqueous two-phase systems (ATPSs) constitutes a powerful tool for purifying bio-materials, such as cells, organelles, proteins, among others. In this work, the extraction of the bovine serum albumin (BSA) has been studied in systems formed by polyethylene glycol (PEG) (1500, 4000, and 6000 g.mol⁻¹) + potassium sodium tartrate + water at 303.15°K. Phase diagrams were obtained by turbidimetry and Merchuk’s method (1998). The experimental tie-lines were described using the Othmer-Tobias and Bancroft correlations. ATPSs were correlated with the nonrandom two-liquid (NRTL) model. The results were considered excellent according to global root-mean-square deviations found which were between 0,72 and 1,13%. The concentrations of the proteins in each phase were determined by spectrophotometry at 280 nm, finding partition efficiencies greater than 71%.

Keywords: aqueous two phases systems, bovine serum albumin , liquid-liquid extraction, polyethylene glycol

Procedia PDF Downloads 147

Authors: Andrey A. Tyuftin, David Clarke, Malco C. Cruz-Romero, Declan Bolton, Seamus Fanning, Shashi K. Pankaj, Carmen Bueno-Ferrer, Patrick J. Cullen, Joe P. Kerry

Abstract:

Prolonging of shelf-life is essential in order to address issues such as; supplier demands across continents, economical profit, customer satisfaction, and reduction of food wastage. Smart packaging solutions presented in the form of naturally occurred antimicrobially-active packaging may be a solution to these and other issues. Gelatin film forming solution with adding of natural sourced antimicrobials is a promising tool for the active smart packaging. The objective of this study was to coat conventional plastic hydrophobic packaging material with hydrophilic antimicrobial active beef gelatin coating and conduct shelf life trials on beef sub-primal cuts. Minimal inhibition concentration (MIC) of Caprylic acid sodium salt (SO) and commercially available Auranta FV (AFV) (bitter oranges extract with mixture of nutritive organic acids) were found of 1 and 1.5 % respectively against bacterial strains Bacillus cereus, Pseudomonas fluorescens, Escherichia coli, Staphylococcus aureus and aerobic and anaerobic beef microflora. Therefore SO or AFV were incorporated in beef gelatin film forming solution in concentration of two times of MIC which was coated on a conventional plastic LDPE/PA film on the inner cold plasma treated polyethylene surface. Beef samples were vacuum packed in this material and stored under chilling conditions, sampled at weekly intervals during 42 days shelf life study. No significant differences (p < 0.05) in the cook loss was observed among the different treatments compared to control samples until the day 29. Only for AFV coated beef sample it was 3% higher (37.3%) than the control (34.4 %) on the day 36. It was found antimicrobial films did not protect beef against discoloration. SO containing packages significantly (p < 0.05) reduced Total viable bacterial counts (TVC) compared to the control and AFV samples until the day 35. No significant reduction in TVC was observed between SO and AFV films on the day 42 but a significant difference was observed compared to control samples with a 1.40 log of bacteria reduction on the day 42. AFV films significantly (p < 0.05) reduced TVC compared to control samples from the day 14 until the day 42. Control samples reached the set value of 7 log CFU/g on day 27 of testing, AFV films did not reach this set limit until day 35 and SO films until day 42 of testing. The antimicrobial AFV and SO coated films significantly prolonged the shelf-life of beef steaks by 33 or 55% (on 7 and 14 days respectively) compared to control film samples. It is concluded antimicrobial coated films were successfully developed by coating the inner polyethylene layer of conventional LDPE/PA laminated films after plasma surface treatment. The results indicated that the use of antimicrobial active packaging coated with SO or AFV increased significantly (p < 0.05) the shelf life of the beef sub-primal. Overall, AFV or SO containing gelatin coatings have the potential of being used as effective antimicrobials for active packaging applications for muscle-based food products.

Keywords: active packaging, antimicrobials, edible coatings, food packaging, gelatin films, meat science

Procedia PDF Downloads 295

Authors: Ilknur Tuncer, Nihayet Bizsel

Abstract:

The studies in bacterial diversity and antimicrobial resistance in coastal areas are important to understand the variability in the community structures and metabolic activities. In the present study, antimicrobial susceptibility and phylogenetic analysis of bacteria isolated from stations with different depths and influenced by terrestrial and marine fluxes in eastern Aegean Sea were illustrated. 51% of the isolates were found as resistant and 14% showed high MAR index indicating the high-risk sources of contamination in the environment. The resistance and the intermediate levels and high MAR index of the study area were 38–60%, 11–38% and 0–40%, respectively. According to 16S rRNA gene analysis, it was found that the isolates belonged to two phyla Firmicutes and Gammaproteobacteria with the genera Bacillus, Halomonas, Oceanobacillus, Photobacterium, Pseudoalteromonas, Psychrobacter, and Vibrio. 47% of Bacillus strains which were dominant among all isolates were resistant. In addition to phylogenetically diverse bacteria, the variability in resistance, intermediate and high MAR index levels of the study area indicated the effect of geographical differences.

Keywords: bacterial diversity, multiple antibiotic resistance, 16S rRNA genes, Aegean Sea

Procedia PDF Downloads 404

Authors: Chuanxiang Cheng, Tiantian Min, Jin Yue

Abstract:

Antimicrobial active packaging enables extensive biological effects to improve food safety. However, the efficacy of antimicrobial packaging hinges on factors including the diffusion rate of the active agent toward the food surface, the initial content in the antimicrobial agent, and the targeted food shelf life. Among the possibilities of antimicrobial packaging design, an interesting approach involves the incorporation of volatile antimicrobial agents into the packaging material. In this case, the necessity for direct contact between the active packaging material and the food surface is mitigated, as the antimicrobial agent exerts its action through the packaging headspace atmosphere towards the food surface. However, it still remains difficult to achieve controlled and precise release of bioactive compounds to the specific target location with required quantity in food packaging applications. Remarkably, the development of stimuli-responsive materials for electrospinning has introduced the possibility of achieving controlled release of active agents under specific conditions, thereby yielding enduring biological effects. Relative humidity (RH) for the storage of food categories such as meat and aquatic products typically exceeds 90%. Consequently, high RH can be used as an abiotic trigger for the release of active agents to prevent microbial growth. Hence, a novel RH - responsive polyvinyl alcohol/chitosan (PVA/CS) composite nanofibrous film incorporated with 4-terpineol/β-cyclodextrin inclusion complexes (4-TA@β-CD ICs) was engineered by electrospinning that can be deposited as a functional packaging materials. The characterization results showed the thermal stability of the films was enhanced after the incorporation due to the hydrogen bonds between ICs and polymers. Remarkably, the 4 wt% 4-TA@β-CD ICs/PVA/CS film exhibited enhanced crystallinity, moderate hydrophilic (Water contact angle of 81.53°), light barrier property (Transparency of 1.96%) and water resistance (Water vapor permeability of 3.17 g mm/m2 h kPa). Moreover, this film also showed optimized mechanical performance with a Young’s modulus of 11.33 MPa, a tensile strength of 19.99 MPa and an elongation at break of 4.44 %. Notably, the antioxidant and antibacterial properties of this packaging material were significantly improved. The film demonstrated the half-inhibitory concentrations (IC50) values of 87.74% and 85.11% for scavenging 2,2-diphenyl-1-picrylhydrazyl (DPPH) and 2, 2′-azinobis (3-ethylbenzothiazoline-6-sulfonic) (ABTS) free radicals, respectively, in addition to an inhibition efficiency of 65% against Shewanella putrefaciens, the characteristic bacteria in aquatic products. Most importantly, the film achieved controlled release of 4-TA under high 98% RH by inducing the plasticization of polymers caused by water molecules, swelling of polymer chains, and destruction of hydrogen bonds within the cyclodextrin inclusion complex. Consequently, low relative humidity is suitable for the preservation of nanofibrous film, while high humidity conditions typical in fresh food packaging environments effectively stimulated the release of active compounds in the film. This film with a long-term antimicrobial effect successfully extended the shelf life of Litopenaeus vannamei shrimp to 7 days at 4 °C. This attractive design could pave the way for the development of new food packaging materials.

Keywords: controlled release, electrospinning, nanofibrous film, relative humidity–responsive, shrimp preservation

Procedia PDF Downloads 55

Authors: Intanri Kurniati, Raja Iqbal Mulya Harahap, Agustyas Tjiptaningrum, Reni Zuraida

Abstract:

Background: Diabetes mellitus is still increasing and has become a health and social burden in the world. It is known that glycation among various proteins is increased in diabetic patients compared with non-diabetic subjects. Some of these glycated proteins are suggested to be involved in the development and progression of chronic diabetic complications. Among these glycated proteins, glycated hemoglobin (HbA1C) is commonly used as the gold standard index of glycemic control in the clinical setting. HbA1C testing has some methods, and the most commonly used is immunoturbidimetry. This research aimed to compare the HbA1c level between immunoturbidimetry and HbA1C level in T2DM patients. Methods: This research involves 77 patients from Abd Muluk Hospital Bandar Lampung; the patient was asked for consent in this research, then underwent phlebotomy to be tested for HbA1C; the sample was then examined for HbA1C with Turbidimetric Inhibition Immunoassay (TINIA) and High-Performance Liquid Chromatography (HPLC) method. Result: Mean± SD of the samples with the TINIA method was 9.2±1,2; meanwhile, the level HbA1C with the HPLC method is 9.6±1,2. The t-test showed no significant difference between the group subjects. (p<0.05). It was proposed that the two methods have high suitability in testing, and both are eligibly used for the patient. Discussion: There was no significant difference among research subjects, indicating that the high conformity of the two methods is suitable to be used for monitoring patients clinically. Conclusion: There is increasing in HbA1C level in a patient with T2DM measured with HPLC and or Turbidimetric Inhibition Immunoassay (TINIA) method, and there were no significant differences among those methods.

Keywords: diabetes mellitus, glycated albumin, HbA1C, HPLC, immunoturbidimetry

Procedia PDF Downloads 92

Authors: Sebaa H., Cherifi F., Djabeur Abderrezak M.

Abstract:

Argania spinosa, Sapotaceae sole representative in Algeria and Morocco; hence it is endemic in these regions. However, it is a recognised oil, forage, and timber tree highly adapted to aridity. The exploitation of the argan fruits produces considerable amounts of under or related products. These products, such as the endocarps of a fruit, recuperated after the use of kernels to extract oil. This research studies in detail the contents of total phenolic content was determined by Folin Ciocalteu reagent and Flavonoids by aluminum chloride colorimetric assay). Antioxidant activity of extracts was expressed as the percentage of DPPH radical inhibition and IC50 values (μg/mL). Antimicrobial activity evaluated using agar disk diffusion method against reference Pseudomonas aeruginosa ATTC 27453, Escherichia coli ATCC 23922. Immature endocarps showed a higher polyphenol content than mature endocarps. The total phenolic content in immature endocarps was found to vary from 983,75+ /- 0.45 to 980,1 +/- 0.43 mg gallic acid equivalents/g dry weight, whereas in mature endocarps, the polyphenol content ranged from 100,58 mg/g +/- 0.42 to 105 +/- 0.55% mg gallic acid equivalent / g dry weight. The flavonoid content was 16.5 mg equivalent catechin/g dry weight and 9.81mg equivalent catechin /g dry weight for immature and mature endocarp fruits, respectively. DPPH assay of the endocarps extract yielded a half-maximal effective concentration (IC50) value in the immature endocarps (549.33 μg/mL) than in mature endocarps (322 μg/mL). This result can be attributed to the higher phenolics and flavonoid compounds in the immature endocarps. Methanol extract of immature endocarps exhibited antibacterial activity against E.colie (inhibition zone, 11mm).

Keywords: antioxidant activity, antimicrobial activity, total phenolic content, DPPH assay

Procedia PDF Downloads 109