Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 5599

Search results for: enzyme activity

5599 Cytotoxic Effect of Purified and Crude Hyaluronidase Enzyme on Hep G2 Cell Line

Authors: Furqan M. Kadhum, Asmaa A. Hussein, Maysaa Ch. Hatem

Abstract:

Hyaluronidase enzyme was purified from the clinical isolate Staphyloccus aureus in three purification steps, first by precipitation with 90% saturated ammonium sulfate, ion exchange chromatography on DEAE-Cellulose, and gel filtration chromatography throughout Sephacryl S-300. Specific activity of the purified enzyme was reached 930 U/mg protein with 7.4 folds of purification and 46.5% recovery. The enzyme has an average molecular weight of about 69 kDa, with an optimum pH of enzyme activity and stability at pH 7, also the optimum temperature for activity was 37oC. The enzyme was stable with full activity at a temperature ranged between 30-40 oC. Metal ions showed variable inhibitory degree with the strongest effect for Fe+3, however, the chelating and reducing agents had no or little effects. Cytotoxic studies for purified and crude hyaluronidase against cancer cell Hep G2 type at different enzyme concentrations and exposure times showed that the inhibition effect of both crude and purified enzyme increased by increasing the enzyme concentration with no change was observed at 24hr, while at 48 and 72 hrs the same inhibition rate were observed for purified enzyme and differ for the crude filtrate.

Keywords: hyaluronidase, S. aureus, metal ions, cytotoxicity

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5598 Production of Linamarase from Lactobacillus delbrueckii NRRL B-763

Authors: Ogbonnaya Nwokoro, Florence O. Anya

Abstract:

Nutritional factors relating to the production of linamarase from Lactobacillus delbrueckii NRRL B–763 were investigated. The microorganism was cultivated in a medium containing 1% linamarin. Enzyme was produced using a variety of carbon substrates but the highest enzyme activity was detected in the presence of salicin (522 U/ml) after 48 h while the lowest yield was observed with CM cellulose (38 U/ml) after 72 h. Enzyme was not produced in the presence of cellobiose. Among a variety of nitrogen substrates tested, peptone supported maximum enzyme production (412 U/ml) after 48 h. Lowest enzyme production was observed with urea (40 U/ml). Organic nitrogen substrates generally supported higher enzyme productivity than inorganic nitrogen substrates. Enzyme activity was observed in the presence of Mn2+ (% relative activity = 216) while Hg2+ was inhibitory (% relative activity = 28). Locally-formulated media were comparable to MRS broth in supporting linamarase production by the bacterium. Higher enzyme activity was produced in media with surfactant than in media without surfactant. The enzyme may be useful in enhanced degradation of cassava cyanide.

Keywords: linamarase, locally formulated media, carbon substrates, nitrogen substrates, metal ions

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5597 The Effect of a Muscarinic Antagonist on the Lipase Activity

Authors: Zohreh Bayat, Dariush Minai-Tehrani

Abstract:

Lipases constitute one of the most important groups of industrial enzymes that catalyze the hydrolysis of triacylglycerol to glycerol and fatty acids. Muscarinic antagonist relieves smooth muscle spasm of the gastrointestinal tract and effect on the cardiovascular system. In this research, the effect of a muscarinic antagonist on the lipase activity of Pseudomonas aeruginosa was studied. Lineweaver–Burk plot showed that the drug inhibited the enzyme by competitive inhibition. The IC50 value (60 uM) and Ki (30 uM) of the drug revealed the drug bound to the enzyme with high affinity. Determination of enzyme activity in various pH and temperature showed that the maximum activity of lipase was at pH 8 and 60°C both in presence and absence of the drug.

Keywords: bacteria, inhibition, kinetics, lipase

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5596 Effect of Ethanol Concentration and Enzyme Pre-Treatment on Bioactive Compounds from Ginger Extract

Authors: S. Lekhavat, T. Kajsongkram, S. Sang-han

Abstract:

Dried ginger was extracted and investigated the effect of ethanol concentration and enzyme pre-treatment on its bioactive compounds in solvent extraction process. Sliced fresh gingers were dried by oven dryer at 70 °C for 24 hours and ground to powder using grinder which their size were controlled by passing through a 20-mesh sieve. In enzyme pre-treatment process, ginger powder was sprayed with 1 % (w/w) cellulase and then was incubated at 45 °C for 2 hours following by extraction process using ethanol at concentration of 0, 20, 40, 60 and 80 % (v/v), respectively. The ratio of ginger powder and ethanol are 1:9 and extracting conditions were controlled at 80 °C for 2 hours. Bioactive compounds extracted from ginger, either enzyme-treated or non enzyme-treated samples, such as total phenolic content (TPC), 6-Gingerol (6 G), 6-Shogaols (6 S) and antioxidant activity (IC50 using DPPH assay), were examined. Regardless of enzyme treatment, the results showed that 60 % ethanol provided the highest TPC (20.36 GAE mg /g. dried ginger), 6G (0.77%), 6S (0.036 %) and the lowest IC50 (625 μg/ml) compared to other ratios of ethanol. Considering the effect of enzyme on bioactive compounds and antioxidant activity, it was found that enzyme-treated sample has more 6G (0.17-0.77 %) and 6S (0.020-0.036 %) than non enzyme-treated samples (0.13-0.77 % 6G, 0.015-0.036 % 6S). However, the results showed that non enzyme-treated extracts provided higher TPC (6.76-20.36 GAE mg /g. dried ginger) and Lowest IC50 (625-1494 μg/ml ) than enzyme-treated extracts (TPC 5.36-17.50 GAE mg /g. dried ginger, IC50 793-2146 μg/ml).

Keywords: antioxidant activity, enzyme, extraction, ginger

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5595 Purification, Biochemical Characterization and Application of an Extracellular Alkaline Keratinase Produced by Aspergillus sp. DHE7

Authors: Dina Helmy El-Ghonemy, Thanaa Hamed Ali

Abstract:

The aim of this study was to purify and characterize a keratinolytic enzyme produced by Aspergillus sp. DHE7 cultured in basal medium containing chicken feather as substrate. The enzyme was purified through ammonium sulfate saturation of 60%, followed by gel filtration chromatography in Sephadex G-100, with a 16.4-purification fold and recovery yield of 52.2%. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis revealed that the purified enzyme is a monomeric enzyme with an apparent molecular mass of 30 kDa — the purified keratinase of Aspergillus sp. DHE7 exhibited activity in a broad range of pH (7- 9) and temperature (40℃-60℃) profiles with an optimal activity at pH eight and 50℃. The keratinolytic activity was inhibited by protease inhibitors such as phenylmethylsulfonyl fluoride and ethylenediaminetetraacetate, while no reduction of activity was detected by the addition of dimethyl sulfoxide (DMSO). Bivalent cations, Ca²⁺ and Mn²⁺, were able to greatly enhance the activity of keratinase by 125.7% and 194.8%, respectively, when used at one mM final concentration. On the other hand, Cu²⁺ and Hg²⁺ inhibited the enzyme activity, which might be indicative of essential vicinal sulfhydryl groups of the enzyme for productive catalysis. Furthermore, the purified keratinase showed significant stability and compatibility against the tested commercial detergents at 37ºC. Therefore, these results suggested that the purified keratinase from Aspergillus sp. DHE7 may have potential use in the detergent industry and should be of interest in the processing of poultry feather waste.

Keywords: Aspergillus sp. DHE7, biochemical characterization, keratinase, purification, waste management

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5594 Medium Design and Optimization for High Β-Galactosidase Producing Microbial Strains from Dairy Waste through Fermentation

Authors: Ashish Shukla, K. P. Mishra, Pushplata Tripathi

Abstract:

This paper investigates the production and optimization of β-galactosidase enzyme using synthetic medium by isolated wild strains (S1, S2) mutated strains (M1, M2) through SSF and SmF. Among the different cell disintegration methods used, the highest specific activity was obtained when the cells were permeabilized using isoamyl alcohol. Wet lab experiments were performed to investigate the effects of carbon and nitrogen substrates present in Vogel’s medium on β-galactosidase enzyme activity using S1, S2, and M1, M2 strains through SSF. SmF experiments were performed for effects of carbon and nitrogen sources in YLK2Mg medium on β-galactosidase enzyme activity using S1, S2 and M1, M2 strains. Effect of pH on β-galactosidase enzyme production was also done using S1, S2, and M1, M2 strains. Results were found to be very appreciable in all the cases.

Keywords: β-galactosidase, cell disintegration, permeabilized, SSF, SmF

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5593 The Modeling of Viscous Microenvironment for the Coupled Enzyme System of Bioluminescence Bacteria

Authors: Irina E. Sukovataya, Oleg S. Sutormin, Valentina A. Kratasyuk

Abstract:

Effect of viscosity of media on kinetic parameters of the coupled enzyme system NADH:FMN-oxidoreductase–luciferase was investigated with addition of organic solvents (glycerol and sucrose), because bioluminescent enzyme systems based on bacterial luciferases offer a unique and general tool for analysis of the many analytes and enzymes in the environment, research, and clinical laboratories and other fields. The possibility of stabilization and increase of activity of the coupled enzyme system NADH:FMN-oxidoreductase–luciferase activity in vicious aqueous-organic mixtures have been shown.

Keywords: coupled enzyme system of bioluminescence bacteria NAD(P)H:FMN-oxidoreductase–luciferase, glycerol, stabilization of enzymes, sucrose

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5592 High Catalytic Activity and Stability of Ginger Peroxidase Immobilized on Amino Functionalized Silica Coated Titanium Dioxide Nanocomposite: A Promising Tool for Bioremediation

Authors: Misha Ali, Qayyum Husain, Nida Alam, Masood Ahmad

Abstract:

Improving the activity and stability of the enzyme is an important aspect in bioremediation processes. Immobilization of enzyme is an efficient approach to amend the properties of biocatalyst required during wastewater treatment. The present study was done to immobilize partially purified ginger peroxidase on amino functionalized silica coated titanium dioxide nanocomposite. Interestingly there was an enhancement in enzyme activity after immobilization on nanosupport which was evident from effectiveness factor (η) value of 1.76. Immobilized enzyme was characterized by transmission electron microscopy, scanning electron microscopy and Fourier transform infrared spectroscopy. Immobilized peroxidase exhibited higher activity in a broad range of pH and temperature as compared to free enzyme. Also, the thermostability of peroxidase was strikingly improved upon immobilization. After six repeated uses, the immobilized peroxidase retained around 62% of its dye decolorization activity. There was a 4 fold increase in Vmax of immobilized peroxidase as compared to free enzyme. Circular dichroism spectroscopy demonstrated conformational changes in the secondary structure of enzyme, a possible reason for the enhanced enzyme activity after immobilization. Immobilized peroxidase was highly efficient in the removal of acid yellow 42 dye in a stirred batch process. Our study shows that this bio-remediating system has remarkable potential for treatment of aromatic pollutants present in wastewater.

Keywords: acid yellow 42, decolorization, ginger peroxidase, immobilization

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5591 Screening, Selection and Optimization of Extracellular Methanol and Ethanol Tolerant Lipase from Acinetobacter sp. K5B4

Authors: Khaled M. Khleifat

Abstract:

An extracellular methanol and ethanol tolerant lipase producing bacterial strain K5b4 was isolated from soil samples contaminated with hydrocarbon residues. It was identified by using morphological and biochemical characteristics and 16srRNA technique as Acinetobacter species. The immobilized lipase from Acinetobacter sp. K5b4 retained more than 98% of its residual activity after incubation with pure methanol and ethanol for 24 hours. The highest hydrolytic activity of the immobilized enzyme was obtained in the presence of 75% (v/v) methanol in the assay solution. In contrary, the enzyme was able to maintain its original activity up to only 25% (v/v) ethanol whereas at elevated concentrations of 50 and 75% (v/v) the enzyme activity was reduced to 10 and 40%, respectively. Maximum lipase activity of 31.5 mU/mL was achieved after 48 hr cultivation when the optimized medium (pH 7.0) that composed of 1.0% (w/v) olive oil, 0.2% (w/v) glycerol, 0.15% (w/v) yeast extract, and 0.05% (w/v) NaCl was inoculated with 0.4% (v/v) seed culture and incubated at 30°C and 150 rpm agitation speed. However, the presence of CaCl2 in the growth media did not show any inhibitory or stimulatory effect on the enzyme production as it compared to the control experiment. Meanwhile, the other mineral salts MgCl2, MnCl2, KCl and CoCl2 were negatively affected the production of lipase enzyme. The inhibition of lipase production from Acinetobacter sp. K5b4 in presence of glucose suggesting that lipase gene expression is prone to catabolic repression.

Keywords: K5B4, methanol and ethanol, acinetobacter, morphological

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5590 The Investigation of Enzymatic Activity in the Soils Under the Impact of Metallurgical Industrial Activity in Lori Marz, Armenia

Authors: T. H. Derdzyan, K. A. Ghazaryan, G. A. Gevorgyan

Abstract:

Beta-glucosidase, chitinase, leucine-aminopeptidase, acid phosphomonoestearse and acetate-esterase enzyme activities in the soils under the impact of metallurgical industrial activity in Lori marz (district) were investigated. The results of the study showed that the activities of the investigated enzymes in the soils decreased with increasing distance from the Shamlugh copper mine, the Chochkan tailings storage facility and the ore transportation road. Statistical analysis revealed that the activities of the enzymes were positively correlated (significant) to each other according to the observation sites which indicated that enzyme activities were affected by the same anthropogenic factor. The investigations showed that the soils were polluted with heavy metals (Cu, Pb, As, Co, Ni, Zn) due to copper mining activity in this territory. The results of Pearson correlation analysis revealed a significant negative correlation between heavy metal pollution degree (Nemerow integrated pollution index) and soil enzyme activity. All of this indicated that copper mining activity in this territory causing the heavy metal pollution of the soils resulted in the inhabitation of the activities of the enzymes which are considered as biological catalysts to decompose organic materials and facilitate the cycling of nutrients.

Keywords: Armenia, metallurgical industrial activity, heavy metal pollutionl, soil enzyme activity

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5589 Assessment of Diagnostic Enzymes as Indices of Heavy Metal Pollution in Tilapia Fish

Authors: Justina I. R. Udotong, Essien U. Essien

Abstract:

Diagnostic enzymes like aspartate aminotransferase (AST), alanine aminotransferase (ALT) and alkaline phosphatase (ALP) were determined as indices of heavy metal pollution in Tilapia guinensis. Three different sets of fishes treated with lead (Pb), iron (Fe) and copper (Cu) were used for the study while a fourth group with no heavy metal served as a control. Fishes in each of the groups were exposed to 2.65 mg/l of Pb, 0.85 mg/l of Fe and 0.35 mg/l of Cu in aerated aquaria for 96 hours. Tissue fractionation of the liver tissues was carried out and the three diagnostic enzymes (AST, ALT, and ALP) were estimated. Serum levels of the same diagnostic enzymes were also measured. The mean values of the serum enzyme activity for ALP in each experimental group were 19.5±1.62, 29.67±2.17 and 1.15±0.27 IU/L for Pb, Fe and Cu groups compared with 9.99±1.34 IU/L enzyme activity in the control. This result showed that Pb and Fe caused increased release of the enzyme into the blood circulation indicating increased tissue damage while Cu caused a reduction in the serum level as compared with the level in the control group. The mean values of enzyme activity obtained in the liver were 102.14±6.12, 140.17±2.06 and 168.23±3.52 IU/L for Pb, Fe and Cu groups, respectively compared to 91.20±9.42 IU/L enzyme activity for the control group. The serum and liver AST and ALT activities obtained in Pb, Fe, Cu and control groups are reported. It was generally noted that the presence of the heavy metal caused liver tissues damage and consequent increased level of the diagnostic enzymes in the serum.

Keywords: diagnostic enzymes, enzyme activity, heavy metals, tissues investigations

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5588 Synthesis and Anti-Inflammatory Activity of Pyrazol-3-yl Thiazole 4-Carboxylic Acid Derivatives Targeting Enzyme in the Leukotriene Pathway

Authors: Shweta Sinha, Mukesh Doble, Manju S. L.

Abstract:

Pyrazole scaffold is an important group of compound in heterocyclic chemistry and is found to possess numerous uses in chemistry. Pyrazole derivatives are also known to possess important biological activities including antitumor, antimicrobial, antiviral, antifungal, anticancer and anti-inflammatory. Inflammation is associated with pain, allergy and asthma. Leukotrienes are mediators of various inflammatory and allergic disorders. 5-Lipoxygenase (5-LOX) is an important enzyme involved in the biosynthesis of leukotrienes and metabolism of arachidonic acid (AA) and thus targeted for anti-inflammation. In vitro inhibitory activity of pyrazol-3-yl thiazole 4-carboxylic acid derivatives is tested against enzyme 5-LOX. Most of these compounds exhibit good inhibitory activity against this enzyme. Binding mode study of these compounds is determined by computational tool. Further experiments are being done to understand the mechanism of action of these compounds in inhibiting this enzyme. To conclude, these compounds appear to be a promising target in drug design against 5-LOX.

Keywords: inflammation, inhibition, 5-lipoxygenase, pyrazole

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5587 Effect of Hemicellulase on Extraction of Essential Oil from Algerian Artemisia campestris

Authors: Khalida Boutemak, Nasssima Benali, Nadji Moulai-Mostefa

Abstract:

Effect of enzyme on the yield and chemical composition of Artemisia campestris essential oil is reported in the present study. It was demonstrated that enzyme facilitated the extraction of essential oil with increase in oil yield and did not affect any noticeable change in flavour profile of the volatile oil. Essential oil was tested for antibacterial activity using Escherichia coli; which was extremely sensitive against control with the largest inhibition (29mm), whereas Staphylococcus aureus was the most sensitive against essential oil obtained from enzymatic pre-treatment with the largest inhibition zone (25mm). The antioxidant activity of the essential oil with hemicellulase pre-treatment (EO2) and control sample (EO1) was determined through reducing power. It was significantly lower than the standard drug (vitamin C) in this order: vitamin C˃EO2˃EO1.

Keywords: Artemisia campestris, enzyme pre-treatment, hemicellulase, antibacterial activity, antioxidant activity

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5586 The Effect of Artesunate on Myeloperoxidase Activity of Human Polymorphonuclear Neutrophil

Authors: J. B. Minari, O. B. Oloyede, A. A. Odutuga

Abstract:

Myeloperoxidase is the most abundant enzyme found in the polymorphonuclear neutrophil and is known to play a central role in the host defense system of the leukocyte. The enzyme has been reported to interact with some drugs to generate free radical which inhibits its activity. This study investigated the effects of artesunate on the activity of the enzyme and the subsequent effect on the host immune system. In investigating the effects of the drugs on myeloperoxidase, the influence of concentration, pH, partition ratio estimation and kinetics of inhibition were studied. This study showed that artesunate is concentration-dependent inhibitor of myeloperoxidase with an IC50 of 0.078mM. Partition ratio estimation showed that 60 enzymatic turnover cycles are required for complete inhibition of myeloperoxidase in the presence of artesunate. The influence of pH on the effect of artesunate on the enzyme showed least activity of myeloperoxidase at physiological pH. The kinetic inhibition studies showed that artesunate caused a competitive inhibition with an increase in the Km value from 0.12mM to 0.26mM and no effect on the Vmax value. The Ki value was estimated to be 2.5mM. The results obtained from this study show that artesunate is a potent inhibitor of myeloperoxidase and it is capable of inactivating the enzyme. It is considered that the inhibition of myeloperoxidase in the presence of artesunate as revealed in this study may partly explain the impairment of polymorphonuclear neutrophil and consequent reduction of the strength of the host defense system against secondary infections.

Keywords: myeloperoxidase, artesunate, inhibition, nuetrophill

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5585 Statistical Modeling for Permeabilization of a Novel Yeast Isolate for β-Galactosidase Activity Using Organic Solvents

Authors: Shweta Kumari, Parmjit S. Panesar, Manab B. Bera

Abstract:

The hydrolysis of lactose using β-galactosidase is one of the most promising biotechnological applications, which has wide range of potential applications in food processing industries. However, due to intracellular location of the yeast enzyme, and expensive extraction methods, the industrial applications of enzymatic hydrolysis processes are being hampered. The use of permeabilization technique can help to overcome the problems associated with enzyme extraction and purification of yeast cells and to develop the economically viable process for the utilization of whole cell biocatalysts in food industries. In the present investigation, standardization of permeabilization process of novel yeast isolate was carried out using a statistical model approach known as Response Surface Methodology (RSM) to achieve maximal b-galactosidase activity. The optimum operating conditions for permeabilization process for optimal β-galactosidase activity obtained by RSM were 1:1 ratio of toluene (25%, v/v) and ethanol (50%, v/v), 25.0 oC temperature and treatment time of 12 min, which displayed enzyme activity of 1.71 IU /mg DW.

Keywords: β-galactosidase, optimization, permeabilization, response surface methodology, yeast

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5584 Prevalence of Cyp2d6 and Its Implications for Personalized Medicine in Saudi Arabs

Authors: Hamsa T. Tayeb, Mohammad A. Arafah, Dana M. Bakheet, Duaa M. Khalaf, Agnieszka Tarnoska, Nduna Dzimiri

Abstract:

Background: CYP2D6 is a member of the cytochrome P450 mixed-function oxidase system. The enzyme is responsible for the metabolism and elimination of approximately 25% of clinically used drugs, especially in breast cancer and psychiatric therapy. Different phenotypes have been described displaying alleles that lead to a complete loss of enzyme activity, reduced function (poor metabolizers – PM), hyperfunctionality (ultrarapid metabolizers–UM) and therefore drug intoxication or loss of drug effect. The prevalence of these variants may vary among different ethnic groups. Furthermore, the xTAG system has been developed to categorized all patients into different groups based on their CYP2D6 substrate metabolization. Aim of the study: To determine the prevalence of the different CYP2D6 variants in our population, and to evaluate their clinical relevance in personalized medicine. Methodology: We used the Luminex xMAP genotyping system to sequence 305 Saudi individuals visiting the Blood Bank of our Institution and determine which polymorphisms of CYP2D6 gene are prevalent in our region. Results: xTAG genotyping showed that 36.72% (112 out of 305 individuals) carried the CYP2D6_*2. Out of the 112 individuals with the *2 SNP, 6.23% had multiple copies of *2 SNP (19 individuals out of 305 individuals), resulting in an UM phenotype. About 33.44% carried the CYP2D6_*41, which leads to decreased activity of the CYP2D6 enzyme. 19.67% had the wild-type alleles and thus had normal enzyme function. Furthermore, 15.74% carried the CYP2D6_*4, which is the most common nonfunctional form of the CYP2D6 enzyme worldwide. 6.56% carried the CYP2D6_*17, resulting in decreased enzyme activity. Approximately 5.73% carried the CYP2D6_*10, consequently decreasing the enzyme activity, resulting in a PM phenotype. 2.30% carried the CYP2D6_*29, leading to decreased metabolic activity of the enzyme, and 2.30% carried the CYP2D6_*35, resulting in an UM phenotype, 1.64% had a whole-gene deletion CYP2D6_*5, thus resulting in the loss of CYP2D6 enzyme production, 0.66% carried the CYP2D6_*6 variant. One individual carried the CYP2D6_*3(B), producing an inactive form of the enzyme, which leads to decrease of enzyme activity, resulting in a PM phenotype. Finally, one individual carried the CYP2D6_*9, which decreases the enzyme activity. Conclusions: Our study demonstrates that different CYP2D6 variants are highly prevalent in ethnic Saudi Arabs. This finding sets a basis for informed genotyping for these variants in personalized medicine. The study also suggests that xTAG is an appropriate procedure for genotyping the CYP2D6 variants in personalized medicine.

Keywords: CYP2D6, hormonal breast cancer, pharmacogenetics, polymorphism, psychiatric treatment, Saudi population

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5583 Investigations of Metals and Metal-Antibrowning Agent Effects on Polyphenol Oxidase Activity from Red Poppy Leaf

Authors: Gulnur Arabaci

Abstract:

Heavy metals are one of the major groups of contaminants in the environment and many of them are toxic even at very low concentration in plants and animals. However, some metals play important roles in the biological function of many enzymes in living organisms. Metals such as zinc, iron, and cooper are important for survival and activity of enzymes in plants, however heavy metals can inhibit enzyme which is responsible for defense system of plants. Polyphenol oxidase (PPO) is a copper-containing metalloenzyme which is responsible for enzymatic browning reaction of plants. Enzymatic browning is a major problem for the handling of vegetables and fruits in food industry. It can be increased and effected with many different futures such as metals in the nature and ground. In the present work, PPO was isolated and characterized from green leaves of red poppy plant (Papaver rhoeas). Then, the effect of some known antibrowning agents which can form complexes with metals and metals were investigated on the red poppy PPO activity. The results showed that glutathione was the most potent inhibitory effect on PPO activity. Cu(II) and Fe(II) metals increased the enzyme activities however, Sn(II) had the maximum inhibitory effect and Zn(II) and Pb(II) had no significant effect on the enzyme activity. In order to reduce the effect of heavy metals, the effects of metal-antibrowning agent complexes on the PPO activity were determined. EDTA and metal complexes had no significant effect on the enzyme. L-ascorbic acid and metal complexes decreased but L-ascorbic acid-Cu(II)-complex had no effect. Glutathione–metal complexes had the best inhibitory effect on Red poppy leaf PPO activity.

Keywords: inhibition, metal, red poppy, poly phenol oxidase (PPO)

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5582 The Construction of a Probiotic Lactic Acid Bacterium Expressing Acid-Resistant Phytase Enzyme

Authors: R. Majidzadeh Heravi, M. Sankian, H. Kermanshahi, M. R. Nassiri, A. Heravi Moussavi, S. A. Lari, A. R. Varasteh

Abstract:

The use of probiotics engineered to express specific enzymes has been the subject of considerable attention in poultry industry because of increased nutrient availability and reduced cost of enzyme supplementation. Phytase enzyme is commonly added to poultry feed to improve digestibility and availability of phosphorus from plant sources. To construct a probiotic with potential of phytate degradation, phytase gene (appA) from E. coli was cloned and transformed into two probiotic bacteria Lactobacillus salivarius and Lactococcus lactis. L. salivarous showed plasmid instability, unable to express the gene. The expression of appA gene in L. lactis was analyzed by detecting specific RNA and zymography assay. Phytase enzyme was isolated from cellular extracts of recombinant L. lactis, showing a 46 kDa band upon the SDS-PAGE analysis. Zymogram also confirmed the phytase activity of the 46 kDa band corresponding to the enzyme. An enzyme activity of 4.9U/ml was obtained in cell extracts of L. lactis. The growth of native and recombinant L. lactis was similar in the presence of two concentrations of ox bile.

Keywords: Lactobacillus salivarus, Lactococcuslactis, recombinant, phytase, poultry

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5581 Biological Regulation of Endogenous Enzymatic Activity of Rainbow Trout (Oncorhynchus Mykiss) with Protease Inhibitors Chickpea in Model Systems

Authors: Delgado-Meza M., Minor-Pérez H.

Abstract:

Protease is the generic name of enzymes that hydrolyze proteins. These are classified in the subgroup EC3.4.11-99X of the classification enzymes. In food technology the proteolysis is used to modify functional and nutritional properties of food, and in some cases this proteolysis may cause food spoilage. In general, seafood and rainbow trout have accelerated decomposition process once it has done its capture, due to various factors such as the endogenous enzymatic activity that can result in loss of structure, shape and firmness, besides the release of amino acid precursors of biogenic amines. Some studies suggest the use of protease inhibitors from legume as biological regulators of proteolytic activity. The enzyme inhibitors are any substance that reduces the rate of a reaction catalyzed by an enzyme. The objective of this study was to evaluate the reduction of the proteolytic activity of enzymes in extracts of rainbow trout with protease inhibitors obtained from chickpea flour. Different proportions of rainbow trout enzyme extract (75%, 50% and 25%) and extract chickpea enzyme inhibitors were evaluated. Chickpea inhibitors were obtained by mixing 5 g of flour in 30 mL of pH 7.0 phosphate buffer. The sample was centrifuged at 8000 rpm for 10 min. The supernatant was stored at -15°C. Likewise, 20 g of rainbow trout were ground in 20 mL of phosphate buffer solution at pH 7.0 and the mixture was centrifuged at 5000 rpm for 20 min. The supernatant was used for the study. In each treatment was determined the specific enzymatic activity with the technique of Kunitz, using hemoglobin as substrate for the enzymes acid fraction and casein for basic enzymes. Also biuret protein was quantified for each treatment. The results showed for fraction of basic enzymes in the treatments evaluated, that were inhibition of endogenous enzymatic activity. Inhibition values compared to control were 51.05%, 56.59% and 59.29% when the proportions of endogenous enzymes extract rainbow trout were 75%, 50% and 25% and the remaining volume used was extract with inhibitors. Treatments with acid enzymes showed no reduction in enzyme activity. In conclusion chickpea flour reduced the endogenous enzymatic activity of rainbow trout, which may favor its application to increase the half-life of this food. The authors acknowledge the funding provided by the CONACYT for the project 131998.

Keywords: rainbouw trout, enzyme inhibitors, proteolysis, enzyme activity

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5580 Magnetite Nanoparticles Immobilized Pectinase: Preparation, Characterization and Application for the Fruit Juices Clarification

Authors: Leila Mosafa, Majid Moghadam, Mohammad Shahedi

Abstract:

In this work, pectinase was immobilized on the surface of silica-coated magnetite nanoparticles via covalent attachment. The magnetite-immobilized enzyme was characterized by Fourier transform infrared spectroscopy, X-ray powder diffraction, scanning electron microscopy and vibrating sample magnetometry techniques. Response surface methodology using Minitab Software was applied for statistical designing of operating conditions in order to immobilize pectinase on magnetic nanoparticles. The optimal conditions were obtained at 30°C and pH 5.5 with 42.97 µl pectinase for 2 h. The immobilization yield was 50.6% at optimized conditions. Compared to the free pectinase, the immobilized pectinase was found to exhibit enhanced enzyme activity, better tolerance to the variation of pH and temperature, and improved storage stability. Both free and immobilized samples reduced the viscosity of apple juice from 1.12 to 0.88 and 0.92 mm2s-1, respectively, after 30 min at their optimum temperature. Furthermore, the immobilized enzyme could be reused six consecutive cycles and the efficiency loss in viscosity reduction was found to be only 8.16%.

Keywords: magnetite nanoparticles, pectinase enzyme, immobilization, juice clarification, enzyme activity

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5579 Characterization of Pectinase from Local Microorganisms to Support Industry Based Green Chemistry

Authors: Sasangka Prasetyawan, Anna Roosdiana, Diah Mardiana, Suratmo

Abstract:

Pectinase are enzymes that hydrolyze pectin compounds. The use of this enzyme is primarily to reduce the viscosity of the beverage thus simplifying the purification process. Pectinase activity influenced by microbial sources . Exploration of two types of microbes that Aspergillus spp. and Bacillus spp. pectinase give different performance, but the use of local strain is still not widely studied. The aim of this research is exploration of pectinase from A. niger and B. firmus include production conditions and characterization. Bacillus firmus incubated and shaken at a speed of 200 rpm at pH variation (5, 6, 7, 8, 9, 10), temperature (30, 35, 40, 45, 50) °C and incubation time (6, 12, 18, 24, 30, 36 ) hours. Media was centrifuged at 3000 rpm, pectinase enzyme activity determined. Enzyme production by A. niger determined to variations in temperature and pH were similar to B. firmus, but the variation of the incubation time was 24, 48, 72, 96, 120 hours. Pectinase crude extract was further purified by precipitation using ammonium sulfate saturation in fraction 0-20 %, 20-40 %, 40-60 %, 60-80 %, then dialyzed. Determination of optimum conditions pectinase activity performed by measuring the variation of enzyme activity on pH (4, 6, 7, 8, 10), temperature (30, 35, 40, 45, 50) °C, and the incubation time (10, 20, 30, 40, 50) minutes . Determination of kinetic parameters of pectinase enzyme reaction carried out by measuring the rate of enzyme reactions at the optimum conditions, but the variation of the concentration of substrate (pectin 0.1 % , 0.2 % , 0.3 % , 0.4 % , 0.5 % ). The results showed that the optimum conditions of production of pectinase from B. firmus achieved at pH 7-8.0, 40-50 ⁰C temperature and fermentation time 18 hours. Purification of pectinase showed the highest purity in the 40-80 % ammonium sulfate fraction. Character pectinase obtained : the optimum working conditions of A. niger pectinase at pH 5 , while pectinase from B. firmus at pH 7, temperature and optimum incubation time showed the same value, namely the temperature of 50 ⁰C and incubation time of 30 minutes. The presence of metal ions can affect the activity of pectinase , the concentration of Zn 2 + , Pb 2 + , Ca 2 + and K + and 2 mM Mg 2 + above 6 mM inhibit the activity of pectinase .

Keywords: pectinase, Bacillus firmus, Aspergillus niger, green chemistry

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5578 Ethanol Precipitation and Characterization of L-Asparaginase from Aspergillus oryzae

Authors: L. L. Tundisi, A. Pessoa Jr., E. B. Tambourgi, E. Silveira, P. G. Mazzola

Abstract:

L-asparaginase (L-ASNase) is the gold standard treatment for acute lymphoblastic leukemia that mainly affects pediatric patients; treatment increases survival from 20% to 90%. The characterization of other L-Asparaginases, apart from the most used from Escherichia coli and Erwinia chrysanthemi, has been reported, but the choice of the most appropriate is still under debate. This choice should be based on its pharmacokinetics, immune hypersensitivity, doses, prices, pharmacodynamics. The main factors influencing the antileukemic activity of ASNase are enzymatic activity, Km, glutaminase activity, clearance of the enzyme and development of resistance. However, most of the commercialized enzyme present an intrinsic glutaminase activity, which is responsible for some side effects. In this study, glutaminase free asparaginase produced from Aspergillus oryzae was precipitated in different percentages of ethanol (0–80%), until optimum ethanol concentration of 60% (w/w) was found. Following, precipitation of crude L-ASNase was performed in a single step, using 60% (w/w) ethanol, under constant agitation and temperature. It presented activity of 135.45 U/mg and after gel filtration chromatography with Sephadex G-the enzymatic activity was 322.02 U/mg. The apparent molecular mass of the purified L-ASNase fraction was estimated by 10% SDS-PAGE. Proteins were stained with Coomassie Brilliant Blue R-250. The molar mass range was from 10 kDa to 250 kDa. L-ASNase from Aspergillus oryzae was characterized aiming possible therapeutic use. Four different buffers (phosphate-citrate buffer pH 2.6 to 5.8; phosphate buffer pH 5.8 to 7.4; Tris - HCl pH 7.4 to 9.0; and carbonate buffer pH 9.8 to 10.6) were used to measure the optimum pH for L-ASNase activity. The optimum temperature for enzyme activity was measured at optimal pH conditions (Tris-HCl and phosphate buffer, pH 7.4) at different temperatures ranging from 5 to 55°C. All activities were calculated by quantifying the free ammonia, using the Nessler reagent. The kinetic parameters calculation, e.g. Michaelis-Menten constant (Km), maximum velocity (Vmax) and Hills coefficient (n), were performed by incubating the enzyme in different concentrations of the substrate at optimum conditions of pH and fitted on Hill’s equation. This glutaminase free asparaginase showed a low Km (3.39 mM and 3.81 mM) and enzymatic activity of 135.45 U/mg after precipitation with ethanol. After gel filtration chromatography it rose to 322.02 U/mg. Optimum activity was found between pH 5.8 - 9.0, best activity results with phosphate buffer pH 7.4 and Tris-HCl pH 7.4 and showed activity from 5°C to 55°C. These results indicate that L-ASNase from A. oryzae has the potential for human use.

Keywords: biopharmaceuticals, bioprocessing, bioproducts, biotechnology, enzyme activity, ethanol precipitation

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5577 Improved Production, Purification and Characterization of Invertase from Penicillium lilacinum by Shaken Flask Technique of Submerged Fermentation

Authors: Kashif Ahmed

Abstract:

Recent years researchers have been motivated towards extensive exploring of living organism, which could be utilized effectively in intense industrial conditions. The present study shows enhanced production, purification and characterization of industrial enzyme, invertase (Beta-D-fructofuranosidase) from Penicillium lilacinum. Various agricultural based by-products (cotton stalk, sunflower waste, rice husk, molasses and date syrup) were used as energy source. The highest amount of enzyme (13.05 Units/mL) was produced when the strain was cultured on growth medium containing date syrup as energy source. Yeast extract was used as nitrogen source after 96 h of incubation at incubation temperature of 40º C. Initial pH of medium was 8.0, inoculum size 6x10⁶ conidia and 200 rev/min agitation rate. The enzyme was also purified (7 folds than crude) and characterized. Molecular mass of purified enzyme (65 kDa) was determined by 10 % SDS-PAGE. Lineweaver-Burk Plot was used to determine Kinetic constants (Vmax 178.6 U/mL/min and Km 2.76 mM). Temperature and pH optima were 55º C and 5.5 respectively. MnCl₂ (52.9 %), MgSO₄ (48.9 %), BaCl₂ (24.6 %), MgCl₂ (9.6 %), CoCl₂ (5.7 %) and NaCl (4.2 %) enhanced the relative activity of enzyme and HgCl₂ (-92.8 %), CuSO₄ (-80.2 %) and CuCl₂ (-76.6 %) were proved inhibitors. The strain was showing enzyme activity even at extreme conditions of temperature (up to 60º C) and pH (up to 9), so it can be used in industries.

Keywords: invertase, Penicillium lilacinum, submerged fermentation, industrial enzyme

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5576 Immobilization Strategy of Recombinant Xylanase from Trichoderma reesei by Cross-Linked Enzyme Aggregates

Authors: S. Md. Shaarani, J. Md. Jahim, R. A. Rahman, R. Md. Illias

Abstract:

Modern developments in biotechnology have paved the way for extensive use of biocatalysis in industries. Although it offers immense potential, industrial application is usually hampered by lack of operational stability, difficulty in recovery as well as limited re-use of the enzyme. These drawbacks, however, can be overcome by immobilization. Cross-linked enzyme aggregates (CLEAs), a versatile carrier-free immobilization technique is one that is currently capturing global interest. This approach involves precipitating soluble enzyme with an appropriate precipitant and subsequent crosslinking by a crosslinking reagent. Without ineffective carriers, CLEAs offer high enzymatic activity, stability and reduced production cost. This study demonstrated successful CLEA synthesis of recombinant xylanase from Trichoderma reesei using ethanol as aggregating agent and glutaraldehyde (2% (v/v); 100 mM) as crosslinker. Effects of additives including proteic feeder such as bovine serum albumin (BSA) and poly-L-Lysine were investigated to reveal its significance in enhancing the performance of enzyme. Addition of 0.1 mg BSA/U xylanase showed considerable increment in CLEA development with approximately 50% retained activity.

Keywords: cross-linked, immobilization, recombinant, xylanase

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5575 Determination of the Inhibitory Effects of N-Methylpyrrole Derivatives on Glutathione Reductase Enzyme

Authors: Esma Kocaoglu, Oktay Talaz, Huseyin Cavdar, Murat Senturk, Deniz Eki̇nci̇

Abstract:

Glutathione reductase (GR) is a crucial antioxidant enzyme which is responsible for the maintenance of the antioxidant GSH (glutathione) molecule. Antimalarial effects of some chemical molecules are attributed to their inhibition of GR; thus inhibitors of this enzyme are expected to be promising candidates for the treatment of malaria. In this work, GR inhibitory properties of N-Methylpyrrole derivatives are reported. Firstly, GR was purified by means of affinity chromatography using 2’,5’-ADP-Sepharose 4B as ligand. Enzymatic activity was measured by Beutler’s method. Synthesis of the compounds was approved by thin layer chromatography and column chromatography. Different inhibitor concentrations were used and all compounds were tested in triplicate at each concentration used. It was found that all compounds have better inhibitory activity than the strong GR inhibitor N,N-bis(2-chloroethyl)-N-nitrosourea, especially three molecules, 8m, 8n, and 8q, are the best among them with low micromolar I₅₀ values. Findings of our study indicate that these Schiff base derivatives are strong GR inhibitors which can be used as leads for designation of novel antimalaria candidates.

Keywords: glutathione reductase, antimalaria, inhibitor, enzyme

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5574 Optimization of Enzymatic Hydrolysis of Cooked Porcine Blood to Obtain Hydrolysates with Potential Biological Activities

Authors: Miguel Pereira, Lígia Pimentel, Manuela Pintado

Abstract:

Animal blood is a major by-product of slaughterhouses and still represents a cost and environmental problem in some countries. To be eliminated, blood should be stabilised by cooking and afterwards the slaughterhouses must have to pay for its incineration. In order to reduce the elimination costs and valorise the high protein content the aim of this study was the optimization of hydrolysis conditions, in terms of enzyme ratio and time, in order to obtain hydrolysates with biological activity. Two enzymes were tested in this assay: pepsin and proteases from Cynara cardunculus (cardosins). The latter has the advantage to be largely used in the Portuguese Dairy Industry and has a low price. The screening assays were carried out in a range of time between 0 and 10 h and using a ratio of enzyme/reaction volume between 0 and 5%. The assays were performed at the optimal conditions of pH and temperature for each enzyme: 55 °C at pH 5.2 for cardosins and 37 °C at pH 2.0 for pepsin. After reaction, the hydrolysates were evaluated by FPLC (Fast Protein Liquid Chromatography) and tested for their antioxidant activity by ABTS method. FPLC chromatograms showed different profiles when comparing the enzymatic reactions with the control (no enzyme added). The chromatogram exhibited new peaks with lower MW that were not present in control samples, demonstrating the hydrolysis by both enzymes. Regarding to the antioxidant activity, the best results for both enzymes were obtained using a ratio enzyme/reactional volume of 5% during 5 h of hydrolysis. However, the extension of reaction did not affect significantly the antioxidant activity. This has an industrial relevant aspect in what concerns to the process cost. In conclusion, the enzymatic blood hydrolysis can be a better alternative to the current elimination process allowing to the industry the reuse of an ingredient with biological properties and economic value.

Keywords: antioxidant activity, blood, by-products, enzymatic hydrolysis

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5573 Effect of Drying Condition on the Wheat Germ Stability Using Fluidized-Bed Dryer

Authors: J. M. Hung, J. S. Chan, M. I. Kuo, D. S. Chan, C. P. Lu

Abstract:

Wheat germ is a by-product obtained from wheat milling and it contains highly concentrated nutrients. Due to highly lipase and lipoxygenase activities, wheat germ products can easily turn into rancid flavor and cause a short life. The objective of this study is to control moisture content and retard lipid hydrolysis by fluidized-bed drying. The raw wheat germ of 2 kg was dried with a vertical batch fluidized bed with the following varying conditions, inlet air temperature of 50, 80 and 120°C, inlet air velocity of 3.62 m/s. The experiment was designed to obtain a final product at around 40°C with water activity of 0.3 ± 0.1. Changes in the moisture content, water activity, enzyme activity of dried wheat germ during storage were measured. Results showed the fluidized-bed drying was found to reduce moisture content, water activity and lipase activity of raw wheat germ. After drying wheat germ, moisture content and water activity were between 5.8% to 7.2% and 0.28 to 0.40 respectively during 12 weeks of storage. The variation range of water activity indicated to retard lipid oxidation. All drying treatments displayed inactivation of lipase, except for drying condition of 50°C which showed relative high enzyme activity. During storage, lipase activity increased slowly during the first 6 weeks of storage and reached a plateau for another 6 weeks. As a result, using a fluidized-bed dryer was found to be effective drying technique in improving storage stability of wheat germ.

Keywords: wheat germ, fluidized-bed dryer, storage, lipase, stability

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5572 Application of Acinetobacter sp. KKU44 for Cellulase Production from Agricultural Waste

Authors: Surasak Siripornadulsil, Nutt Poomai, Wilailak Siripornadulsil

Abstract:

Due to a high ethanol demand, the approach for effective ethanol production is important and has been developed rapidly worldwide. Several agricultural wastes are highly abundant in celluloses and the effective cellulose enzymes do exist widely among microorganisms. Accordingly, the cellulose degradation using microbial cellulose to produce a low-cost substrate for ethanol production has attracted more attention. In this study, the cellulose producing bacterial strain has been isolated from rich straw and identified by 16S rDNA sequence analysis as Acinetobacter sp. KKU44. This strain is able to grow and exhibit the cellulose activity. The optimal temperature for its growth and cellulose production is 37 °C. The optimal temperature of bacterial cellulose activity is 60 °C. The cellulose enzyme from Acinetobacter sp. KKU44 is heat-tolerant enzyme. The bacterial culture of 36 h. showed highest cellulose activity at 120 U/mL when grown in LB medium containing 2% (w/v). The capability of Acinetobacter sp. KKU44 to grow in cellulosic agricultural wastes as a sole carbon source and exhibiting the high cellulose activity at high temperature suggested that this strain could be potentially developed further as a cellulose degrading strain for a production of low-cost substrate used in ethanol production.

Keywords: cellulose enzyme, bagasse, rice straw, rice husk, acinetobacter sp. KKU44

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5571 Structure, Bioinformatics Analysis and Substrate Specificity of a 6-Phospho-β-Glucosidase Glycoside Hydrolase 1 Enzyme from Bacillus licheniformis

Authors: Wayde Veldman, Ozlem T. Bishop, Igor Polikarpov

Abstract:

In bacteria, mono and disaccharides are phosphorylated during uptake into the cell via the widely used phosphoenolpyruvate (PEP)-dependent phosphotransferase transport system. As an initial step in the phosphorylated disaccharide metabolism pathway, certain glycoside hydrolase family 1 (GH1) enzymes play a crucial role in releasing phosphorylated and non-phosphorylated monosaccharides. However, structural determinants for the specificity of these enzymes still need to be clarified. GH1 enzymes are known to have a wide array of functions. According to the CAZy database, there are twenty-one different enzymatic activities in the GH1 family. Here, the structure and substrate specificity of a GH1 enzyme from Bacillus licheniformis, hereafter known as BlBglH, was investigated. The sequence of the enzyme BlBglH was compared to the sequences of other characterized GH1 enzymes using sequence alignment, sequence identity calculations, phylogenetic analysis, and motif discovery. Through these various analyses, BlBglH was found to have sequence features characteristic of the 6-phospho-β-glucosidase activity enzymes. Additionally, motif and structure comparisons of the three most commonly studied GH1 enzyme-activities revealed a shared loop amongst the different structures that consist of different sequence motifs – this loop is thought to guide specific substrates (depending on activity) towards the active-site. To further affirm BlBglH enzyme activity, molecular docking and molecular dynamics simulations were performed. Docking was carried out using 6-phospho-β-glucosidase enzyme-activity positive (p-Nitrophenyl-beta-D-glucoside-6-phosphate) and negative (p-Nitrophenyl-beta-D-galactoside-6-phosphate) control ligands, followed by 400 ns molecular dynamics simulations. The positive-control ligand maintained favourable interactions within the active site until the end of the simulation. The negative-control ligand was observed exiting the enzyme at 287 ns. Binding free energy calculations showed that the positive-control complex had a substantially more favourable binding energy compared to the negative-control complex. Jointly, the findings of this study suggest that the BlBglH enzyme possesses 6-phospho-β-glucosidase enzymatic activity.

Keywords: 6-P-β-glucosidase, glycoside hydrolase 1, molecular dynamics, sequence analysis, substrate specificity

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5570 Characterisation of Chitooligomers Prepared with the Aid of Cellulase, Xylanase and Chitosanase

Authors: Anna Zimoch-Korzycka, Dominika Kulig, Andrzej Jarmoluk

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The aim of this study was to obtain chitooligosaccharides from chitosan with better functional properties using three different enzyme preparations and compare the products of enzymatic hydrolysis. Commercially available cellulase (CL), xylanase (X) and chitosanase (CS) preparations were used to investigate hydrolytic activity on chitosan (CH) with low molecular weight and DD of 75-85%. It has been reported that CL and X have side activities of other enzymes, such as β-glucanase or β-glucosidase. CS enzyme has a foreign activity of chitinase. Each preparation was used in 1000 U of activity and in the same reaction conditions. The degree of deacetylation and molecular weight of chitosan were specified using titration and viscometric methods, respectively. The hydrolytic activity of enzymes preparations on chitosan was monitored by dynamic viscosity measurement. After 4 h reaction with stirring, solutions were filtered and chitosan oligomers were isolated by methanol solution into two fractions: precipitate (A) and supernatant (B). A Fourier-transform infrared spectroscopy was used to characterize the structural changes of chitosan oligomers fractions and initial chitosan. Furthermore, the solubility of lyophilized hydrolytic mixture (C) and two chitooligomers fractions (A, B) of each enzyme hydrolysis was assayed. The antioxidant activity of chitosan oligomers was evaluated as DPPH free radical scavenging activity. The dynamic viscosity measured after addition of enzymes preparation to the chitosan solution decreased dramatically over time in the sample with X in comparison to solution without the enzyme. For mixtures with CL and CS, lower viscosities were also recorded but not as low as the ones with X. A and B fractions were characterized by the most similar viscosity obtained by the xylanase hydrolysis and were 15 mPas and 9 mPas, respectively. Structural changes of chitosan oligomers A, B, C and their differences related with various enzyme preparations used were confirmed. Water solubility of A fractions was not possible to filter and the result was not recorded. Solubility of supernatants was approximately 95% and was higher than hydrolytic mixture. It was observed that the DPPH radical scavenging effect of A, B, C samples is the highest for X products and was approximately 13, 17, 19% respectively. In summary, a mixture of chitooligomers may be useful for the design of edible protective coatings due to the improved biophysical properties.

Keywords: cellulase, xylanase, chitosanase, chitosan, chitooligosaccharides

Procedia PDF Downloads 254