Search results for: Bacillus subtilis bacteria
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 1639

Search results for: Bacillus subtilis bacteria

1399 The Antimicrobial Activity of Marjoram Essential Oil Against Some Antibiotic Resistant Microbes Isolated from Hospitals

Authors: R. A. Abdel Rahman, A. E. Abdel Wahab, E. A. Goghneimy, H. F. Mohamed, E. M. Salama

Abstract:

Infectious diseases are a major cause of death worldwide. The treatment of infections continues to be problematic in modern time because of the severe side effects of some drugs and the growing resistance to antimicrobial agents. Hence, the search for newer, safer and more potent antimicrobials is a pressing need. Herbal medicines have received much attention as a source of new antibacterial drugs since they are considered time-tested and comparatively safe both for human use and the environment. In the present study, the antimicrobial activity of marjoram (Origanum majorana L.) essential oil on some gram positive and gram negative reference bacteria, as well as some hospital resistant microbes, was tested. Marjoram oil was extracted and the oil chemical constituents were identified using GC/MS analysis. Staphylococcus aureas ATCC 6923, Pseudomonus auregonosa ATCC 9027, Bacillus subtilis ATCC 6633, E. coli ATCC 8736 and two hospital resistant microbes isolates 16 and 21 were used. The two isolates were identified by biochemical tests and 16s rRNA as proteus spp. and Enterococcus facielus. The effect of different concentrations of essential oils on bacterial growth was tested using agar disk diffusion assay method to determine the minimum inhibitory concentrations and using micro dilution method to determine the minimum bactericidal concentrations. Marjoram oil was found to be effective against both reference and hospital resistance strains. Hospital strains were more resistant to marjoram oil than reference strains. P. auregonosa growth was completely inhibited at a low concentration of oil (4µl/ml). The other reference strains showed sensitivity to marjoram oil at concentrations ranged from 5 to 7µl/ml. The two hospital strains showed sensitivity at media containing 10 and 15µl/ml oil. The major components of oil were terpineol, cis-beta (23.5%), 1,6 – octadien –3-ol,3,7-dimethyl, 2 aminobenzoate (10.9%), alpha terpieol (8.6%) and linalool (6.3%). Scanning electron microscope (SEM) and transmission electron microscope (TEM) analysis were used to determine the difference between treated and untreated hospital strains. SEM results showed that treated cells were smaller in size than control cells. TEM data showed that cell lysis has occurred to treated cells. Treated cells have ruptured cell wall and appeared empty of cytoplasm compared to control cells which shown to be intact with normal volume of cytoplasm. The results indicated that marjoram oil has a positive antimicrobial effect on hospital resistance microbes. Natural crude extracts can be perfect resources for new antimicrobial drugs.

Keywords: antimicrobial activity, essential oil, hospital resistance microbes, marjoram

Procedia PDF Downloads 415
1398 Antibacterial Activity of Endophytic Bacteria against Multidrug-Resistant Bacteria: Isolation, Characterization, and Antibacterial Activity

Authors: Maryam Beiranvand, Sajad Yaghoubi

Abstract:

Background: Some microbes can colonize plants’ inner tissues without causing obvious damage and can even produce useful bioactive substances. In the present study, the diversity of the endophytic bacteria associated with medicinal plants from Iran was investigated by culturing techniques, molecular gene identification, as well as measuring them for antibacterial activity. Results: In the spring season from 2013 to 2014, 35 herb pharmacology samples were collected, sterilized, meshed, and then cultured on selective media culture. A total of 199 endophytic bacteria were successfully isolated from 35 tissue cultures of medical plants, and sixty-seven out of 199 bacterial isolates were subjected to identification by the 16S rRNA gene sequence analysis method. Based on the sequence similarity gene and phylogenetic analyses, these isolates were grouped into five classes, fourteen orders, seventeen families, twenty-one genera, and forty strains. The most abundant group of endophytic bacteria was actinobacterial, consisting of thirty-two (47%) out of 67 bacterial isolates. Ten (22.3%) out of 67 bacterial isolates remained unidentified and classified at the genus level. The signature of the 16S rRNA gene formed a distinct line in a phylogenetic tree showing that they might be new species of bacteria. One (5.2%) out of 67 bacterial isolates was still not well categorized. Forty-two out of 67 strains were candidates for antimicrobial activity tests. Nineteen (45%) out of 42 strains showed antimicrobial activity multidrug resistance (MDR); thirteen (68%) out of 19 strains were allocated to classes actinobacteria. Four (21%) out of 19 strains belonged to the Bacillaceae family, one (5.2%) out of 19 strains was the Paenibacillaceae family, and one (5.2%) out of 19 strains belonged to the Pseudomonadaceae family. The other twenty-three strains did not show inhibitory activities. Conclusions: Our research showed a high-level phylogenetic diversity and the intoxicating antibiotic activity of endophytic bacteria in the herb pharmacology of Iran.

Keywords: Antibacterial activity, endophytic bacteria, multidrug-resistant bacteria, whole genom sequencing

Procedia PDF Downloads 57
1397 Examining the Role of Soil pH on the Composition and Abundance of Nitrite Oxidising Bacteria

Authors: Mansur Abdulrasheed, Hussein I. Ibrahim, Ahmed F. Umar

Abstract:

Nitrification, the microbial oxidation of ammonia to nitrate (NO3-) via nitrite (NO2-) is a vital process in the biogeochemical nitrogen cycle and is performed by two distinct functional groups; ammonia oxidisers (comprised of ammonia oxidising bacteria (AOB) and ammonia oxidising archaea (AOA)) and nitrite oxidising bacteria. Autotrophic nitrification is said to occur in acidic soils, even though most laboratory cultures of isolated ammonia and nitrite oxidising bacteria fail to grow below neutral pH. Published studies revealed that soil pH is a major driver for determining the distribution and abundance of AOB and AOA. To determine whether distinct populations of nitrite oxidising bacteria within the lineages of Nitrospira and Nitrobacter are adapted to a particular range of pH as observed in ammonia oxidising organisms, the community structure of Nitrospira-like and Nitrobacter-like NOB were examined across a pH gradient (4.5–7.5) by amplifying nitrite oxido-reductase (nxrA) and 16S rRNA genes followed by denaturing gradient gel electrophoresis (DGGE). The community structure of both Nitrospira and Nitrobacter changed with soil pH, with distinct populations observed in acidic and neutral soils. The abundance of Nitrospira-like 16S rRNA and Nitrobacter-like nxrA gene copies contrasted across the pH gradient. Nitrobacter-like nxrA gene abundance decreased with increasing soil pH, whereas Nitrospira-like 16S rRNA gene abundance increased with increasing pH. Findings indicated that abundance and distributions of soil NOB is influence by soil pH.

Keywords: nitrospira, nitrobacter, nitrite-oxidizing bacteria, nitrification, pH, soil

Procedia PDF Downloads 268
1396 Secondary Metabolite Profiling and Antimicrobial Activity of Leaf Extract of Tecomella undulata (Sm.) Seem

Authors: Richa Bhardwaj

Abstract:

Tecomella undulata (Sm.) Seem is a monotypic genus belonging to family Bignoniaceae. The plant holds tremendous potential of medicinal value and has been traditionally used in various ailments like syphilis, leukoderma, blood disorders to name a few. The plant has gained prominence due to the presence of some prominent secondary metabolites. The present study focuses on the GC-MS analysis of leaf extracts of T. undulata which revealed the presence of certain bioactive compounds like stigmasterol, sitosterol, thiazoline, phytol, pthalic acid, methyl alpha ketopalmitate and so forth. A total of about 20 bioactive compounds were identified from the leaf extract spectra. Antimicrobial activity of the leaf extract was assayed against pathogenic bacteria and fungi. The alkaloids from leaf extracts showed antimicrobial activity against E.coli and B.subtilis. The flavonoids from leaves showed positive activity against Penicillium species and Candida albicans. The study thus infers that the presence of bioactive components may be the principle behind the antimicrobial property of different plant parts and therefore Tecomella forms a potential plant for herbal drug formulation.

Keywords: Tecomella undulata, bioactive compounds, GC-MS, antimicrobial activity

Procedia PDF Downloads 117
1395 Detection and Molecular Identification of Bacteria Forming Polyhydroxyalkanoate and Polyhydroxybutyrate Isolated from Soil in Saudi Arabia

Authors: Ali Bahkali, Rayan Yousef Booq, Mohammad Khiyami

Abstract:

Soil samples were collected from five different regions in the Kingdom of Saudi Arabia. Microbiological methods included dilution methods and pour plates to isolate and purify bacteria soil. The ability of isolates to develop biopolymer was investigated on petri dishes containing elements and substance concentrations stimulating developing biopolymer. Fluorescent stains, Nile red and Nile blue were used to stain the bacterial cells developing biopolymers. In addition, Sudan black was used to detect biopolymers in bacterial cells. The isolates which developed biopolymers were identified based on their gene sequence of 1 6sRNA and their ability to grow and synthesize PHAs on mineral medium supplemented with 1% dates molasses as the only carbon source under nitrogen limitation. During the study 293 bacterial isolates were isolated and detected. Through the initial survey on the petri dishes, 84 isolates showed the ability to develop biopolymers. These bacterial colonies developed a pink color due to accumulation of the biopolymers in the cells. Twenty-three isolates were able to grow on dates molasses, three strains of which showed the ability to accumulate biopolymers. These strains included Bacillus sp., Ralstonia sp. and Microbacterium sp. They were detected by Nile blue A stain with fluorescence microscopy (OLYMPUS IX 51). Among the isolated strains Ralstonia sp. was selected after its ability to grow on molasses dates in the presence of a limited nitrogen source was detected. The optimum conditions for formation of biopolymers by isolated strains were investigated. Conditions studied included, best incubation duration (2 days), temperature (30°C) and pH (7-8). The maximum PHB production was raised by 1% (v1v) when using concentrations of dates molasses 1, 2, 3, 4 and 5% in MSM. The best inoculated with 1% old inoculum (1= OD). The ideal extraction method of PHA and PHB proved to be 0.4% sodium hypochlorite solution, producing a quantity of polymer 98.79% of the cell's dry weight. The maximum PHB production was 1.79 g/L recorded by Ralstonia sp. after 48 h, while it was 1.40 g/L produced by R.eutropha ATCC 17697 after 48 h.

Keywords: bacteria forming polyhydroxyalkanoate, detection, molecular, Saudi Arabia

Procedia PDF Downloads 320
1394 Bacteriological Culture Methods and its Uses in Clinical Pathology

Authors: Prachi Choudhary, Jai Gopal Sharma

Abstract:

Microbial cultures determine the type of organism, its abundance in the tested sample, or both. It is one of the primary diagnostic methods of microbiology. It is used to determine the cause of infectious disease by letting the agent multiply in a predetermined medium. Different bacteria produce colonies that may be very distinct from the bacterial species that produced them. To culture any pathogen or microorganism, we should first know about the types of media used in microbiology for culturing. Sometimes sub culturing is also done in various microorganisms if some mixed growth is seen in culture. Nearly 3 types of culture media based on consistency – solid, semi-solid, and liquid (broth) media; are further explained in the report. Then, The Five I's approach is a method for locating, growing, observing, and characterizing microorganisms, including inoculation and incubation. Isolation, inspection, and identification. For identification of bacteria, we have to culture the sample like urine, sputum, blood, etc., on suitable media; there are different methods of culturing the bacteria or microbe like pour plate method, streak plate method, swabbing by needle, pipetting, inoculation by loop, spreading by spreader, etc. After this, we see the bacterial growth after incubation of 24 hours, then according to the growth of bacteria antibiotics susceptibility test is conducted; this is done for sensitive antibiotics or resistance to that bacteria, and also for knowing the name of bacteria. Various methods like the dilution method, disk diffusion method, E test, etc., do antibiotics susceptibility tests. After that, various medicines are provided to the patients according to antibiotic sensitivity and resistance.

Keywords: inoculation, incubation, isolation, antibiotics suspectibility test, characterizing

Procedia PDF Downloads 46
1393 Antimicrobial Properties of Copper in Gram-Negative and Gram-Positive Bacteria

Authors: Travis J. Meyer, Jasodra Ramlall, Phyo Thu, Nidhi Gadura

Abstract:

For centuries humans have used the antimicrobial properties of copper to their advantage. Yet, after all these years the underlying mechanisms of copper mediated cell death in various microbes remain unclear. We had explored the hypothesis that copper mediated increased levels of lipid peroxidation in the membrane fatty acids is responsible for increased killing inEscherichia coli. In this study we show that in both gram positive (Staphylococcus aureus) and gram negative (Pseudomonas aeruginosa) bacteria there is a strong correlation between copper mediated cell death and increased levels of lipid peroxidation. Interestingly, the non-spore forming gram positive bacteria as well as gram negative bacteria show similar patterns of cell death, increased levels of lipid peroxidation, as well as genomic DNA degradation, however there is some difference inloss in membrane integrity upon exposure to copper alloy surface.

Keywords: antimicrobial, copper, gram positive, gram negative

Procedia PDF Downloads 442
1392 β-Lactamase Inhibitory Effects of Anchusa azurea Extracts

Authors: Naoual Boussoualim, Hayat Trabsa, Iman Krache, Lekhmici Arrar, Abderrahmane Baghiani

Abstract:

Resistance to antibiotics has emerged following their widespread use; the important mechanism of beta-lactam resistance in bacteria is the production of beta-lactamase. In order to find new bioactive beta-lactamase inhibitors, this study investigated the inhibition effect of the extracts of Anchusa azurea (AA) on a beta-lactamase from Bacillus cereus. The extracts exerted inhibitory effects on beta-lactamase in a dose-dependent manner, the results showed that the crude extract (BrE) and the ethyl acetate extract (AcE) of Anchusa azurea showed a very high inhibitory activity at a concentration of 10 mg, the percentage of inhibition was between 58% and 68%. Not all extracts were as potent as the original inhibitors such as clavulanic acid, the isolation and the structural elucidation of the active constituents in these extracts will provide useful means in the development of beta -lactamase inhibitors.

Keywords: Anchusa azurea, natural product, resistance, antibiotics, beta-lactamase, inhibitors

Procedia PDF Downloads 481
1391 Screening and Improved Production of an Extracellular β-Fructofuranosidase from Bacillus Sp

Authors: Lynette Lincoln, Sunil S. More

Abstract:

With the rising demand of sugar used today, it is proposed that world sugar is expected to escalate up to 203 million tonnes by 2021. Hydrolysis of sucrose (table sugar) into glucose and fructose equimolar mixture is catalyzed by β-D-fructofuranoside fructohydrolase (EC 3.2.1.26), commonly called as invertase. For fluid filled center in chocolates, preparation of artificial honey, as a sweetener and especially to ensure that food stuffs remain fresh, moist and soft for longer spans invertase is applied widely and is extensively being used. From an industrial perspective, properties such as increased solubility, osmotic pressure and prevention of crystallization of sugar in food products are highly desired. Screening for invertase does not involve plate assay/qualitative test to determine the enzyme production. In this study, we use a three-step screening strategy for identification of a novel bacterial isolate from soil which is positive for invertase production. The primary step was serial dilution of soil collected from sugarcane fields (black soil, Maddur region of Mandya district, Karnataka, India) was grown on a Czapek-Dox medium (pH 5.0) containing sucrose as the sole C-source. Only colonies with the capability to utilize/breakdown sucrose exhibited growth. Bacterial isolates released invertase in order to take up sucrose, splitting the disaccharide into simple sugars. Secondly, invertase activity was determined from cell free extract by measuring the glucose released in the medium at 540 nm. Morphological observation of the most potent bacteria was examined by several identification tests using Bergey’s manual, which enabled us to know the genus of the isolate to be Bacillus. Furthermore, this potent bacterial colony was subjected to 16S rDNA PCR amplification and a single discrete PCR amplicon band of 1500 bp was observed. The 16S rDNA sequence was used to carry out BLAST alignment search tool of NCBI Genbank database to obtain maximum identity score of sequence. Molecular sequencing and identification was performed by Xcelris Labs Ltd. (Ahmedabad, India). The colony was identified as Bacillus sp. BAB-3434, indicating to be the first novel strain for extracellular invertase production. Molasses, a by-product of the sugarcane industry is a dark viscous liquid obtained upon crystallization of sugar. An enhanced invertase production and optimization studies were carried out by one-factor-at-a-time approach. Crucial parameters such as time course (24 h), pH (6.0), temperature (45 °C), inoculum size (2% v/v), N-source (yeast extract, 0.2% w/v) and C-source (molasses, 4% v/v) were found to be optimum demonstrating an increased yield. The findings of this study reveal a simple screening method of an extracellular invertase from a rapidly growing Bacillus sp., and selection of best factors that elevate enzyme activity especially utilization of molasses which served as an ideal substrate and also as C-source, results in a cost-effective production under submerged conditions. The invert mixture could be a replacement for table sugar which is an economic advantage and reduce the tedious work of sugar growers. On-going studies involve purification of extracellular invertase and determination of transfructosylating activity as at high concentration of sucrose, invertase produces fructooligosaccharides (FOS) which possesses probiotic properties.

Keywords: Bacillus sp., invertase, molasses, screening, submerged fermentation

Procedia PDF Downloads 205
1390 Biosorption of Metal Ions from Sarcheshmeh Acid Mine Drainage by Immobilized Bacillus thuringiensis in a Fixed-Bed Column

Authors: V. Khosravi, F. D. Ardejani, A. Aryafar, M. Sedighi

Abstract:

Heavy metals have a damaging impact for the environment, animals and humans due to their extreme toxicity and removing them from wastewaters is a very important and interesting task in the field of water pollution control. Biosorption is a relatively new method for treatment of wastewaters and recovery of heavy metals. In this study, a continuous fixed bed study was carried out by using Bacillus thuringiensis as a biosorbent for the removal of Cu and Mn ions from Sarcheshmeh Acid Mine Drainage (AMD). The effect of operating parameters such as flow rate and bed height on the sorption characteristics of B. thuringiensis was investigated at pH 6.0 for each metal ion. The experimental results showed that the breakthrough time decreased with increasing flow rate and decreasing bed height. The data also indicated that the equilibrium uptake of both metals increased with decreasing flow rate and increasing bed height. BDST, Thomas, and Yoon–Nelson models were applied to experimental data to predict the breakthrough curves. All models were found suitable for describing the whole dynamic behavior of the column with respect to flow rate and bed height. In order to regenerate the adsorbent, an elution step was carried out with 1 M HCl and five adsorption-desorption cycles were carried out in continuous manner.

Keywords: acid mine drainage, bacillus thuringiensis, biosorption, cu and mn ions, fixed bed

Procedia PDF Downloads 365
1389 Removal of Heavy Metals Pb, Zn and Cu from Sludge Waste of Paper Industries Using Biosurfactant

Authors: Nurul Hidayati

Abstract:

Increasing public awareness of environmental pollution influences the search and development of technologies that help in clean up of organic and inorganic contaminants such as metals. Sludge waste of paper industries as toxic and hazardous material from specific source contains Pb, Zn, and Cu metal from waste soluble ink. An alternative and eco-friendly method of remediation technology is the use of biosurfactants and biosurfactant-producing microorganisms. Soil washing is among the methods available to remove heavy metal from sediments. The purpose of this research is to study effectiveness of biosurfactant with concentration = CMC for the removal of heavy metals, lead, zinc and copper in batch washing test under four different biosurfactant production by microbial origin. Pseudomonas putida T1(8), Bacillus subtilis 3K, Acinetobacter sp, and Actinobacillus sp was grown on mineral salt medium that had been already added with 2% concentration of molasses that it is a low cost application. The samples were kept in a shaker 120 rpm at room temperature for 3 days. Supernatants and sediments of sludge were separated by using a centrifuge and samples from supernatants were measured by atomic absorption spectrophotometer. The highest removal of Pb was up to 14,04% by Acinetobacter sp. Biosurfactant of Pseudomonas putida T1(8) have the highest removal for Zn and Cu up to 6,5% and 2,01% respectively. Biosurfactants have a role for removal process of the metals, including wetting, contact of biosurfactant to the surface of the sediments and detachment of the metals from the sediment. Biosurfactant has proven its ability as a washing agent in heavy metals removal from sediments, but more research is needed to optimize the process of removal heavy metals.

Keywords: biosurfactant, removal of heavy metals, sludge waste, paper industries

Procedia PDF Downloads 290
1388 Desulfurization of Crude Oil Using Bacteria

Authors: Namratha Pai, K. Vasantharaj, K. Haribabu

Abstract:

Our Team is developing an innovative cost effective biological technique to desulfurize crude oil. ’Sulphur’ is found to be present in crude oil samples from .05% - 13.95% and its elimination by industrial methods is expensive currently. Materials required :- Alicyclobacillus acidoterrestrius, potato dextrose agar, oxygen, Pyragallol and inert gas(nitrogen). Method adapted and proposed:- 1) Growth of bacteria studied, energy needs. 2) Compatibility with crude-oil. 3) Reaction rate of bacteria studied and optimized. 4) Reaction development by computer simulation. 5) Simulated work tested by building the reactor. The method being developed requires the use of bacteria Alicyclobacillus acidoterrestrius - an acidothermophilic heterotrophic, soil dwelling aerobic, Sulfur bacteria. The bacteria are fed to crude oil in a unique manner. Its coated onto potato dextrose agar beads, cultured for 24 hours (growth time coincides with time when it begins reacting) and fed into the reactor. The beads are to be replenished with O2 by passing them through a jacket around the reactor which has O2 supply. The O2 can’t be supplied directly as crude oil is inflammable, hence the process. Beads are made to move around based on the concept of fluidized bed reactor. By controlling the velocity of inert gas pumped , the beads are made to settle down when exhausted of O2. It is recycled through the jacket where O2 is re-fed and beads which were inside the ring substitute the exhausted ones. Crude-oil is maintained between 1 atm-270 M Pa pressure and 45°C treated with tartaric acid (Ph reason for bacteria growth) for optimum output. Bacteria being of oxidising type react with Sulphur in crude-oil and liberate out SO4^2- and no gas. SO4^2- is absorbed into H2O. NaOH is fed once reaction is complete and beads separated. Crude-oil is thus separated of SO4^2-, thereby Sulphur, tartaric acid and other acids which are separated out. Bio-corrosion is taken care of by internal wall painting (phenolepoxy paints). Earlier methods used included use of Pseudomonas and Rhodococcus species. They were found to be inefficient, time and energy consuming and reduce the fuel value as they fed on skeleton.

Keywords: alicyclobacillus acidoterrestrius, potato dextrose agar, fluidized bed reactor principle, reaction time for bacteria, compatibility with crude oil

Procedia PDF Downloads 289
1387 Metagenomics Analysis on Microbial Communities of Sewage Sludge from Nyeri-Kangemi Wastewater Treatment Plant, Nyeri County-Kenya

Authors: Allan Kiptanui Kimisto, Geoffrey Odhiambo Ongondo, Anastasia Wairimu Muia, Cyrus Ndungu Kimani

Abstract:

The major challenge to proper sewage sludge treatment processes is the poor understanding of sludge microbiome diversities. This study applied the whole-genome. shotgun metagenomics technique to profile the microbial composition of sewage sludge in two active digestion lagoons at the Nyeri-Kangemi Wastewater Treatment Plant in Nyeri County, Kenya. Total microbial community DNA was extracted from samples using the available ZymoBIOMICS™ DNA Miniprep Kit and sequenced using Shotgun metagenomics. Samples were analyzed using MG-RAST software (Project ID: mgp100988), which allowed for comparing taxonomic diversity before β-diversities studies for Bacteria, Archaea and Eukaryotes. The study identified 57 phyla, 145 classes, 301 orders, 506 families, 963 genera, and 1980 species. Bacteria dominated the microbes and comprised 28 species, 51 classes, 110 orders, 243 families, 597 genera, and 1518 species. The Bacteroides(6.77%) were dominant, followed by Acinetobacter(1.44%) belonging to the Gammaproteobacteria and Acidororax (1.36%), Bacillus (1.24%) and Clostridium (1.02%) belonging to Betaproteobacteria. Archaea recorded 5 phyla, 13 classes, 19 orders, 29 families, 60 genera,and87 species, with the dominant genera being Methanospirillum (16.01%), methanosarcina (15.70%), and Methanoregula(14.80%) and Methanosaeta (8.74%), Methanosphaerula(5.48%) and Methanobrevibacter(5.03%) being the subdominant group. The eukaryotes were the least in abundance and comprised 24 phyla, 81 classes, 301 orders, 506 families, 963 genera, and 980 species. Arabidopsis (4.91%) and Caenorhabditis (4.81%) dominated the eukaryotes, while Dityostelium (3.63%) and Drosophila(2.08%) were the subdominant genera. All these microbes play distinct roles in the anaerobic treatment process of sewage sludge. The local sludge microbial composition and abundance variations may be due to age difference differences between the two digestion lagoons in operation at the plant and the different degradation rales played by the taxa. The information presented in this study can help in the genetic manipulation or formulation of optimal microbial ratios to improve their effectiveness in sewage sludge treatment. This study recommends further research on how the different taxa respond to environmental changes over time and space.

Keywords: shotgun metagenomics, sludge, bacteria, archaea, eukaryotes

Procedia PDF Downloads 62
1386 Microbial Deterioration of Some Different Archaeological Objects Made from Cellulose by Bacillus Group

Authors: Mohammad Abdel Fattah Mohammad Kewisha

Abstract:

Microbial deterioration of ancient materials became one of the biggest problems facing the workers in the field of cultural heritage protection because the microbial deterioration of artifacts causes detrimental effects on the aesthetic value of the monuments due to colonization, whether they are made of inorganic materials such as stone or organic like wood, textiles, wall paintings, and paper. So, the early identification of the bacterial strains that caused deterioration is the most important point for the protection of monument objects. The present study focuses on the Bacillus spp. group, which was isolated from some biodeterioration monuments from different areas of Egypt. The investigated objects in this study were made from organic materials (cellulose), paper, textile, and wood. Isolated strains were identified up to the species level biochemically. Eleven bacterial isolates were obtained from collected samples. They were taken from different archaeological objects, four microbicides, cetrimonium bromide, sodium azide, tetraethyl ammonium bromide, and dichloroxylenol, at various concentrations ranging from 25 ppm to 500 ppm. They were screened for their antibacterial activity against the Bacillus spp. isolates, and detection of Minimum inhibitory concentration (MIC). It was also necessary to indicate the ideal Minimum inhibitory concentration for each strain for the purpose of biotreatment of the infected monuments with less damaging effect on monument materials.

Keywords: microbial deterioration, ancient materials, heritage protection, protection of monuments, biodeteriorative monuments

Procedia PDF Downloads 35
1385 Removal of Polycyclic Aromatic Hydrocarbons (PAHS) and the Response of Indigenous Bacteria in Highly Contaminated Aged Soil after Persulfate Oxidation

Authors: Yaling Gou, Sucai Yang, Pengwei Qiao

Abstract:

Integrated chemical-biological treatment is an attractive alternative to remove polycyclic aromatic hydrocarbons (PAHs) from contaminated soil; wherein indigenous bacteria is the key factor for the biodegradation of residual PAHs concentrations after the application of chemical oxidation. However, the systematical study on the impact of persulfate (PS) oxidation on indigenous bacteria as well as PAHs removal is still scarce. In this study, the influences of different PS dosages (1%, 3%, 6%, and 10% [w/w]), as well as various activation methods (native iron, H2O2, alkaline, ferrous iron, and heat) on PAHs removal and indigenous bacteria in highly contaminated aged soil were investigated. Apparent degradation of PAHs in the soil treated with PS oxidation was observed, and the removal efficiency of total PAHs in the soil ranged from 38.28% to 79.97%. The removal efficiency of total PAHs in the soil increased with increasing consumption of PS. However, the bacterial abundance in soil was negatively affected following oxidation for all of the treatments added with PS, with bacterial abundance in the soil decreased by 0.89~2.88 orders of magnitude compared to the untreated soil. Moreover, the number of total bacteria in the soil decreased as PS consumption increased. Different PS activation methods and PS dosages exhibited different influences on the bacterial community composition. Bacteria capable of degrading PAHs under anoxic conditions were composed predominantly by Proteobacteria and Firmicutes. The total amount of Proteobacteria and Firmicutes also decreased with increasing consumption of PS. The results of this study provide important insight into the design of PAHs contaminated soil remediation projects.

Keywords: activation method, chemical oxidation, indigenous bacteria, polycyclic aromatic hydrocarbon

Procedia PDF Downloads 96
1384 Inhibitory Activity of Lactic Acid Bacteria on the Growth and Biogenic Amines Production by Foodborne Pathogens and Food Spoilage Bacteria

Authors: Abderrezzak khatib

Abstract:

Biogenic amines are low molecular weight nitrogenous compounds that have the potential to accumulate in food, posing a significant risk to food safety and human health. In this study, we investigated the inhibitory activity of three strains of lactic acid bacteria (LAB), against the growth and production of biogenic amines by both foodborne pathogens and food spoilage bacteria. The foodborne pathogens studied included Staphylococcus aureus, Pseudomonas aeruginosa, and Salmonella Paratyphi, while the food spoilage bacteria comprised Enterobacter cloacae and Proteus mirabilis. The methodology involved bacterial growth determination in petri dishes, bacterial culture extraction and derivatization, and biogenic amine analysis using HPLC. Our findings revealed that the inhibitory effects of LAB on these pathogens varied, with all three LAB strains demonstrating a remarkable reduction in the total bacterial count when combined with most pathogens, compared to the individual cultures of the pathogens. Furthermore, the presence of LAB in co-cultures with the pathogens resulted in a significant decrease in the production of tyramine and other biogenic amines by the pathogens themselves. These results suggest that LAB strains hold considerable promise in preventing the accumulation of biogenic amines in food products, thereby enhancing food safety. This study provides insights into the potential utilization of LAB in the context of preserving and ensuring the safety of food products. It highlights the significance of conducting additional research endeavors to elucidate the underlying mechanisms involved and to identify the precise bioactive compounds that are responsible for the observed inhibitory effects.

Keywords: food safety, lactic acid bacteria, foodborne pathogens, food spoilage bacteria, biogenic amines, tyrosine

Procedia PDF Downloads 20
1383 Probiotics’ Antibacterial Activity on Beef and Camel Minced Meat at Altered Ranges of Temperature

Authors: Rania Samir Zaki

Abstract:

Because of their inhibitory effects, selected probiotic Lactobacilli may be used as antimicrobial against some hazardous microorganisms responsible for spoilage of fresh minced beef (cattle) minced meat and camel minced meat. Lactic acid bacteria were isolated from camel meat. These included 10 isolates; 1 Lactobacillus fermenti, 4 Lactobacillus plantarum, 4 Lactobacillus pulgaricus, 3 Lactobacillus acidophilus and 1 Lactobacillus brevis. The most efficient inhibitory organism was Lactobacillus plantarum which can be used as a propiotic with antibacterial activity. All microbiological analyses were made at the time 0, first day and the second day at altered ranges of temperature [4±2 ⁰C (chilling temperature), 25±2 ⁰C, and 38±2 ⁰C]. Results showed a significant decrease of pH 6.2 to 5.1 within variant types of meat, in addition to reduction of Total Bacterial Count, Enterococci, Bacillus cereus and Escherichia coli together with the stability of Coliforms and absence of Staphylococcus aureus.

Keywords: antibacterial, camel meat, inhibition, probiotics

Procedia PDF Downloads 266
1382 Bioremediation of Polychlorinated Biphenyl (PCBS) Contaminated Soils: A Case Study from Rietvlei Farm at Borehole No. 11, Limpopo Province, South Africa

Authors: D. Sengani, N. Potgieter, P. E. L. Mojapelo

Abstract:

Three bacteria species which comprise of Gram negative and Gram positive microorganisms were isolated and identified on the basis of morpho-cultural study, catalase tests, oxidase tests and biochemical characteristics were found belonging to different genera including Burkholderia cepacia, Pasteurella pneumotropica and Enterococcus faecalis. The main objective of this study was to isolate and identify PCB degrading bacteria from PCB contaminated soils and test them for their degradation ability of PCBs in natural habitat conditions. The results indicated an overall decrease of PCB concentration level with the gradient average ranging from 1.5 to 1.8 respectively. Enterococcus faecalis removed as much as 32% of PCBs in the contaminated soil samples. Whereas Pasteurella pneumotropica could remove 24% of PCBs, Burkholderia cepacia 21% of PCBs and the mixed culture removed 23%. Data showed that the three bacterial strains could tolerate high concentration of PCBs. The results provided the evidence that naturally occurring bacteria in soil contaminated with PCBs have the potential to degrade PCBs. Statistical analysis showed that there was a significant positive correlation between bacteria growth and treatment with a coefficient of (r) =0.1459 and p value < 0.001.

Keywords: bacteria, bioaccumulation, biodegradation, bioremediation, polychlorinated biphenyls

Procedia PDF Downloads 219
1381 Potential Application of Thyme (Thymus vulgaris L.) Essential Oil as Antibacterial Drug in Aromatherapy

Authors: Ferhat Mohamed Amine, Boukhatem Mohamed Nadjib, Chemat Farid

Abstract:

The Lamiaceae family is widely spread in Algeria. Due to the application of Thymus species growing wild in Algeria as a culinary herb and in folk medicine, the purpose of the present work was to evaluate antimicrobial activities of their essential oils and relate them with their chemical composition, for further application in food and pharmaceutical industries as natural valuable products. The extraction of the Thymus vulgaris L. essential oil (TVEO) was obtained by steam distillation. Chemical composition of the TVEO was determined by Gas Chromatography. A total of thirteen compounds were identified. Carvacrol (83.8%) was the major component, followed by cymene (8.15%) and terpinene (4.96%). Antibacterial action of the TVEO against 23 clinically isolated bacterial strains was determined by using agar disc diffusion and vapour diffusion methods at different doses. By disc diffusion method, TVEO showed potent antimicrobial activity against gram-positive bacteria more than gram-negative strains and antibiotic discs. The Diameter of Inhibition Zone (DIZ) varied from 25 to 60 mm for S. aureus, B. subtilisand E. coli. However, the results obtained by both agar diffusion and vapour diffusion methods were different. Significantly higher antibacterial effect was observed in the vapour phase at lower doses. S. aureus and B. subtilis were the most susceptible strains to the oil vapour. Therefore, smaller doses of EO in the vapour phase can be inhibitory to pathogenic bacteria. There is growing evidence that TVEO in vapour phase are effective antiseptic systems and appears worthy to be considered for practical uses in the treatment of human infections oras air decontaminants in hospital. TVEO has considerable antibacterial activity deserving further investigation for clinical applications. Also whilst the mode of action remains mainly undetermined, this experimental approach will need to continue.

Keywords: antimicrobial drugs, carvacrol, disc diffusion, Thymus vulgaris, vapour diffusion

Procedia PDF Downloads 341
1380 Res2ValHUM: Creation of Resource Management Tool and Microbial Consortia Isolation and Identification

Authors: A. Ribeiro, N. Valério, C. Vilarinho, J. Araujo, J. Carvalho

Abstract:

Res2ValHUM project involves institutions from the Spanish Autonomous Region of Galicia and the north of Portugal (districts of Porto and Braga) and has as overall objectives of promotion of composting as an process for the correct managing of organic waste, valorization of compost in different fields or applications for the constitution of products with high added value, reducing of raw materials losses, and reduction of the amount of waste throw in landfills. Three main actions were designed to achieve the objectives: development of a management tool to improve collection and residue channeling for composting, sensibilization of the population for composting and characterization of the chemical and biological properties of compost and humic and fulvic substances to envisage high-value applications of compost. Here we present the cooperative activity of Galician and northern Portuguese institutions to valorize organic waste in both regions with common socio-economic characteristics and residue management problems. Results from the creation of the resource manage tool proved the existence of a large number of agricultural wastes that could be valorized. In the North of Portugal, the wastes from maize, oats, potato, apple, grape pomace, rye, and olive pomace can be highlighted. In the Autonomous Region of Galicia the wastes from maize, wheat, potato, apple, and chestnuts can be emphasized. Regarding the isolation and identification of microbial consortia from compost samples, results proved microorganisms belong mainly to the genus Bacillus spp. Among all the species identified in compost samples, Bacillus licheniformis can be highlighted in the production of humic and fulvic acids.

Keywords: agricultural wastes, Bacillus licheniformis, Bacillus spp., humic-acids, fulvic-acids

Procedia PDF Downloads 94
1379 Improving the Ability of Constructed Wetlands to Treat Acid Mine Drainage

Authors: Chigbo Emmanuel Ikechukwu

Abstract:

Constructed wetlands are seen as a potential means of ameliorating the poor quality water that derives from coal and gold mining operations. However, the processes whereby a wetland environment is able to improve water quality are not well understood and techniques for optimising their performance poorly developed. A parameter that may be manipulated in order to improve the treatment capacity of a wetland is the substrate in which the aquatic plants are rooted. This substrate can provide an environment wherein sulphate reducing bacteria, which contribute to the removal of contaminants from the water, are able to flourish. The bacteria require an energy source which is largely provided by carbon in the substrate. This paper discusses the form in which carbon is most suitable for the bacteria and describes the results of a series of experiments in which different materials were used as substrate. Synthetic acid mine drainage was passed through an anaerobic bioreactor that contained either compost or cow manure. The effluent water quality was monitored with respect to time and the effect of the substrate composition discussed.

Keywords: constructed wetland, bacteria, carbon, acid mine drainage, sulphate

Procedia PDF Downloads 410
1378 Bacteriological Screening and Antibiotic – Heavy Metal Resistance Profile of the Bacteria Isolated from Some Amphibian and Reptile Species of the Biga Stream in Turkey

Authors: Nurcihan Hacioglu, Cigdem Gul, Murat Tosunoglu

Abstract:

In this article, the antibiogram and heavy metal resistance profile of the bacteria isolated from total 34 studied animals (Pelophylax ridibundus = 12, Mauremys rivulata = 14, Natrix natrix = 8) captured around the Biga Stream, are described. There was no database information on antibiogram and heavy metal resistance profile of bacteria from these area’s amphibians and reptiles. In this study, a total of 200 bacteria were successfully isolated from cloaca and oral samples of the aquatic amphibians and reptiles as well as from the water sample. According to Jaccard’s similarity index, the degree of similarity in the bacterial flora was quite high among the amphibian and reptile species under examination, whereas it was different from the bacterial diversity in the water sample. The most frequent isolates were A. hydrophila (31.5%), B. pseudomallei (8.5%), and C. freundii (7%). The total numbers of bacteria obtained were as follows: 45 in P. ridibundus, 45 in N. natrix 30 in M. rivulata, and 80 in the water sample. The result showed that cefmetazole was the most effective antibiotic to control the bacteria isolated in this study and that approximately 93.33% of the bacterial isolates were sensitive to this antibiotic. The Multiple Antibiotic Resistances (MAR) index indicated that P. ridibundus (0.95) > N. natrix (0.89) > M. rivulata (0.39). Furthermore, all the tested heavy metals (Pb+2, Cu+2, Cr+3, and Mn+2) inhibit the growth of the bacterial isolates at different rates. Therefore, it indicated that the water source of the animals was contaminated with both antibiotic residues and heavy metals.

Keywords: bacteriological quality, amphibian, reptile, antibiotic, heavy metal resistance

Procedia PDF Downloads 351
1377 Molecular Evolutionary Relationships Between O-Antigens of Enteric Bacteria

Authors: Yuriy A. Knirel

Abstract:

Enteric bacteria Escherichia coli is the predominant facultative anaerobe of the colonic flora, and some specific serotypes are associated with enteritis, hemorrhagic colitis, and hemolytic uremic syndrome. Shigella spp. are human pathogens that cause diarrhea and bacillary dysentery (shigellosis). They are in effect E. coli with a specific mode of pathogenicity. Strains of Salmonella enterica are responsible for a food-borne infection (salmonellosis), and specific serotypes cause typhoid fever and paratyphoid fever. All these bacteria are closely related in respect to structure and genetics of the lipopolysaccharide, including the O-polysaccharide part (O‑antigen). Being exposed to the bacterial cell surface, the O antigen is subject to intense selection by the host immune system and bacteriophages giving rise to diverse O‑antigen forms and providing the basis for typing of bacteria. The O-antigen forms of many bacteria are unique, but some are structurally and genetically related to others. The sequenced O-antigen gene clusters between conserved galF and gnd genes were analyzed taking into account the O-antigen structures established by us and others for all S. enterica and Shigella and most E. coli O-serogroups. Multiple genetic mechanisms of diversification of the O-antigen forms, such as lateral gene transfer and mutations, were elucidated and are summarized in the present paper. They include acquisition or inactivation of genes for sugar synthesis or transfer or recombination of O-antigen gene clusters or their parts. The data obtained contribute to our understanding of the origins of the O‑antigen diversity, shed light on molecular evolutionary relationships between the O-antigens of enteric bacteria, and open a way for studies of the role of gene polymorphism in pathogenicity.

Keywords: enteric bacteria, O-antigen gene cluster, polysaccharide biosynthesis, polysaccharide structure

Procedia PDF Downloads 109
1376 Microalgae Bacteria Granules, an Alternative Technology to the Conventional Wastewater Treatment: Structural and Metabolic Characterization

Authors: M. Nita-Lazar, E. Manea, C. Bumbac, A. Banciu, C. Stoica

Abstract:

The population and economic growth have generated a significant new number of pollutant compounds which have to be degraded before reaching the environment. The wastewater treatment plants (WWTPs) have been the last barrier between the domestic and/or industrial wastewaters and the environment. At present, the conventional WWTPs have very high operational costs, most of them linked to the aeration process (60-65% from total energy costs related to wastewater treatment). In addition, they have had a low efficiency in pollutants removal such as pharmaceutical and other resilient anthropogenic compounds. In our study, we have been focused on new wastewater treatment strategies to enhance the efficiency of pollutants removal and decrease the wastewater treatment operational costs. The usage of mixed microalgae-bacteria granules technology generated high efficiency and low costs by a better harvesting and less expensive aeration. The intertrophic relationships between microalgae and bacteria have been characterized by the structure of the population community to their metabolic relationships. The results, obtained by microscopic studies, showed well-organized and stratified microalgae-bacteria granules where bacteria have been enveloped in the microalgal structures. Moreover, their population community structure has been modulated as well as their nitrification, denitrification processes (analysis based on qPCR genes expression) by the type of the pollutant compounds and amounts. In conclusion, the understanding and modulation of intertrophic relationships between microalgae and bacteria could be an economical and technological viable alternative to the conventional wastewater treatment. Acknowledgements: This research was supported by grant PN-III-P4-ID-PCE-2016-0865 from the Romanian National Authority for Scientific Research and Innovation CNCS/CCCDI-UEFISCDI.

Keywords: activated sludge, bacteria, granules, microalgae

Procedia PDF Downloads 83
1375 Metabolic Regulation of Rhizobacteria for Cool-Season Grass Tolerance to Heat Stress

Authors: Kashif Jaeel, Bingru Huang

Abstract:

Stress-induced accumulation of ethylene exacerbates drought damages in plants, and suppressing stress induction of ethylene may promote plant tolerance to heat stress. The objective of this study was to investigate the effects of endophytic bacteria (Paraburkholderia aspalathi) with 1-aminocyclopropane-1-carboxylic acid (ACC) deaminase enzymes in suppressing ethylene production on plant tolerance to heat stress and underlying physiological mechanisms of P. aspalathi-regulation in creeping bentgrass (Agrostis stolonifera). A novel strain of P. aspalathi, ‘WSF23’, with ACC deaminase activity was used to inoculate the roots of plants (cv. ‘Penncross’) subjected to heat stress in controlled-environment chambers. Inoculation with WSF23 bacteria resulted in improved shoot and root growth during heat stress. The differential changes in metabolite regulation due to the bacterial inoculation could contribute to ACC deamination bacteria-improved heat tolerance in cool-season grass species.

Keywords: rhizobacteria, grass, heat, plant metabolism, soil bacteria

Procedia PDF Downloads 36
1374 Advanced Oxidation Processes as a Pre-oxidation Step for Biological Treatment of Leachate from Technical Landfills

Authors: Ala Abdessemed, Mohamed Seddik Oussama Belahmadi, Nabil Charchar, Abdefettah Gherib, Bradai Fares, Boussadia Chouaib Nour El-Islem

Abstract:

Algerian cities are confronted with large quantities of waste generated by the disposal of household and similar residues in technical landfills (CET), such as the one in the location of Batna. The interaction between waste components and incoming water generates leachates rich in organic matter and trace elements, which require treatment before discharge. The aim of this study was to propose an effective process for treating the leachates, which were subjected to an initial chemical treatment using the (H₂O₂/UV) system. Optimal treatment conditions were determined at [H₂O₂] of 0.3 M and pH of 8.6. Next, two hybrid biological treatment systems were applied: hybrid system I (H₂O₂/UV/bacteria) and hybrid system II (H₂O₂/UV/bacteria/microalgae). The three processes resulted in the following degradation rates, expressed in terms of total organic carbon (TOC) 27.4% for the (H₂O₂/UV) system; 58.1% for the hybrid system I (H₂O₂/UV/Bacteria); 67.86% for the hybrid system II (H₂O₂/UV/Bacteria/Microalgae). This study demonstrates that a hybrid approach combining advanced oxidation processes and biological treatments is a highly effective alternative to achieve satisfactory treatment.

Keywords: leachate, landfill, advanced oxidation processes, biological treatment, bacteria, microalgae, total organic carbon

Procedia PDF Downloads 37
1373 Production of Soy Yoghurt Using Soymilk-Based Lactic Acid Bacteria as Starter Culture

Authors: Ayobami Solomon Popoola, Victor N. Enujiugha

Abstract:

Production of soy-yogurt by fermentation of soymilk with lactic acid bacteria isolated from soymilk was studied. Soymilk was extracted from dehulled soybean seeds and pasteurized at 95 °C for 15 min. The soymilk was left to naturally ferment (temperature 40 °C; time 8 h) and lactic acid bacteria were isolated, screened and selected for yogurt production. Freshly prepared soymilk was pasteurized (95 °C, 15 min), inoculated with the lactic acid bacteria isolated (3% w/v starter culture) and incubated at 40 °C for 8 h. The yogurt produced was stored at 4 °C. Investigations were carried out with the aim of improving the sensory qualities and acceptability of soy yogurt. Commercial yogurt was used as a control. The percentage of soymilk inoculated was 70% of the broth. Soy-yoghurt samples produced were subsequently subjected to biochemical and microbiological assays which included total viable counts of fresh milk and soy-based yoghurt; proximate composition of functional soy-based yoghurt fermented with Lactobacillus plantarum; changes in pH, Titratable acidity, and lactic acid bacteria during a 14 day period of storage; as well as morphological and biochemical characteristics of lactic acid bacteria isolated. The results demonstrated that using Lactobacillus plantarum to inoculate soy milk for yogurt production takes about 8 h. The overall acceptability of the soy-based yogurt produced was not significantly different from that of the control sample. The use of isolate from soymilk had the added advantage of reducing the cost of yogurt starter culture, thereby making soy-yogurt, a good source of much desired good quality protein. However, more experiments are needed to improve the sensory qualities such as beany or astringent flavor and color.

Keywords: soy, soymilk, yoghurt, starter culture

Procedia PDF Downloads 224
1372 Application of Phenol Degrading Microorganisms for the Treatment of Olive Mill Waste (OMW)

Authors: M. A. El-Khateeb

Abstract:

The growth of the olive oil production in Saudi Arabia peculiarly in Al Jouf region in recent years has been accompanied by an increase in the discharge of associated processing waste. Olive mill waste is produced throughout the extraction of oil from the olive fruit using the traditional mill and press process. Deterioration of the environment due to olive mill disposal wastes is a serious problem. When olive mill waste disposed into the soil, it affects soil quality, soil micro flora, and also toxic to plants. The aim of this work is to isolate microorganism (bacterial or fungal strains) from OMW capable of degrading phenols. Olive mill wastewater, olive mill waste and soil (beside oil production mill) contaminated with olive waste were used for isolation of phenol tolerant microorganisms. Four strains (two fungal and two bacterial) were isolated from olive mill waste. The isolated strains were Candida tropicalis and Phanerochaete chrysosporium (fungal strains) and Bacillus sp. and Rhodococcus sp. (bacterial strains). These strains were able to degrade phenols and could be used for bioremediation of olive mill waste.

Keywords: bioremediation, bacteria, fungi, Sakaka

Procedia PDF Downloads 328
1371 Phytochemical Screening and in vitro Antibacterial and Antioxidant Potential of Microalgal Strain, Cymbella

Authors: S. Beekrum, B. Odhav, R. Lalloo, E. O. Amonsou

Abstract:

Marine microalgae are rich sources of the novel and biologically active metabolites; therefore, they may be used in the food industry as natural food ingredients and functional foods. They have several biological applications related with health benefits, among others. In the past decades, food scientists have been searching for natural alternatives to replace synthetic antioxidants. The use of synthetic antioxidants has decreased due to their suspected activity as promoters of carcinogenesis, as well as consumer rejection of synthetic food additives. The aim of the study focused on screening of phytochemicals from Cymbella biomass extracts, and to examine the in vitro antioxidant and antimicrobial potential. Cymbella biomass was obtained from CSIR (South Africa), and four different solvents namely methanol, acetone, n-hexane and water were used for extraction. To take into account different antioxidant mechanisms, seven different antioxidant assays were carried out. These include free radical scavenging (DPPH assay), Trolox equivalent antioxidant capacity (TEAC assay), radical cation (ABTS assay), superoxide anion radical scavenging, reducing power, determination of total phenolic compounds and determination of total flavonoid content. The total content of phenol and flavonoid in extracts were determined as gallic acid equivalent, and as rutin equivalent, respectively. The in vitro antimicrobial effect of extracts were tested against some pathogens (Staphylococcus aureus, Listeria monocytogenes, Bacillus subtilis, Salmonella enteritidis, Escherichia coli, Pseudomonas aeruginosa and Candida albicans), using the disc diffusion assay. Qualitative analyses of phytochemicals were conducted by chemical tests to screen for the presence of tannins, flavonoids, terpenoids, phenols, steroids, saponins, glycosides and alkaloids. The present investigation revealed that all extracts showed relatively strong antibacterial activity against most of the tested bacteria. The methanolic extract of the biomass contained a significantly high phenolic content of 111.46 mg GAE/g, and the hexane extract contained 65.279 mg GAE/g. Results of the DPPH assay showed that the biomass contained strong antioxidant capacity, 79% in the methanolic extract and 85% in the hexane extract. Extracts have displayed effective reducing power and superoxide anion radical scavenging. Results of this study have highlighted potential antioxidant activity in the methanol and hexane extracts. The obtained results of the phytochemical screening showed the presence of terpenoids, flavonoids, phenols and saponins. The use of Cymbella as a natural antioxidant source and a potential source of antibacterial compounds and phytochemicals in the food industry appears promising and should be investigated further.

Keywords: antioxidants, antimicrobial, Cymbella, microalgae, phytochemicals

Procedia PDF Downloads 421
1370 Optimization the Multiplicity of Infection for Large Produce of Lytic Bacteriophage pAh6-C

Authors: Sang Guen Kim, Sib Sankar Giri, Jin Woo Jun, Saekil Yun, Hyoun Joong Kim, Sang Wha Kim, Jung Woo Kang, Se Jin Han, Se Chang Park

Abstract:

Emerging of the super bacteria, bacteriophages are considered to be as an alternative to antibiotics. As the demand of phage increased, economical and large production of phage is becoming one of the critical points. For the therapeutic use, what is important is to eradicate the pathogenic bacteria as fast as possible, so higher concentration of phages is generally needed for effective therapeutic function. On the contrary, for the maximum production, bacteria work as a phage producing factory. As a microbial cell factory, bacteria is needed to last longer producing the phages without eradication. Consequently, killing the bacteria fast has a negative effect on large production. In this study, Multiplicity of Infection (MOI) was manipulated based on initial bacterial inoculation and used phage pAh-6C which has therapeutic effect against Aeromonas hydrophila. 1, 5 and 10 percent of overnight bacterial culture was inoculated and each bacterial culture was co-cultured with the phage of which MOI of 0.01, 0.0001, and 0.000001 respectively. Simply changing the initial MOI as well as bacterial inoculation concentration has regulated the production quantity of the phage without any other changes to culture conditions. It is anticipated that this result can be used as a foundational data for mass production of lytic bacteriophages which can be used as the therapeutic bio-control agent.

Keywords: bacteriophage, multiplicity of infection, optimization, Aeromonas hydrophila

Procedia PDF Downloads 277