Search results for: enzyme catalysis

Authors: G. K. Sruthi, Sila Bhattacharya

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Sorghum is an important food crop in the dry tropical areas of the world, and possesses significant levels of phytochemicals and dietary fiber to offer health benefits. However, the absence of gluten is a limitation for converting the sorghum dough into sheeted/flattened/rolled products. Chapathi/roti (flat unleavened bread prepared conventionally from whole wheat flour dough) was attempted from sorghum as wheat gluten causes allergic reactions leading to celiac disease. Dynamic oscillatory rheology of sorghum flour dough (control sample) and enzyme treated sorghum doughs were studied and linked to the attributes of the finished ready-to-eat product. Enzymes like amylase, xylanase, and a mix of amylase and xylanase treated dough affected drastically the rheological behaviour causing a lowering of dough consistency. In the case of amylase treated dough, marked decrease of the storage modulus (G') values from 85513 Pa to 23041 Pa and loss modulus (G") values from 8304 Pa to 7370 Pa was noticed while the phase angle (δ) increased from 5.6 to 10.1o for treated doughs. There was a 2 and 3 fold increase in the total sugar content after α-amylase and xylanase treatment, respectively, with simultaneous changes in the structure of the dough and finished product. Scanning electron microscopy exhibited enhanced extent of changes in starch granules. Amylase and mixed enzyme treatment produced a sticky dough which was difficult to roll/flatten. The dough handling properties were improved by the use of xylanase and quality attributes of the chapath/roti. It is concluded that enzyme treatment can offer improved rheological status of gluten free doughs and products.

Keywords: sorghum dough, amylase, xylanase, dynamic oscillatory rheology, sensory assessment

Procedia PDF Downloads 401

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

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

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

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Authors: Merouani Djilali Redha, F. Abdelmalek, A. A. Addou

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Advanced oxidation processes (AOPs) utilizing Homogenous photocatalysis (Fenton and photo-Fenton reactions), and Heterogeneous photocatalyse (TiO2 and ZnO) were investigated for the degradation of commercial azo dye ‘Orange G’ wastewater. Fenton and photo-Fenton experimental conditions were: Hydrogen peroxide concentration (10-2 M), Ferrous ions concentration (5.10-4 M), pH (2.8 – 3), UV lamp power (6 watt). Adding more ferrous ions enhanced the oxidation rate for the H2O2/Fe2+ and UV/H2O2/Fe2+ processes. The optimum catalyst loading was found 2.0 g.L-1 in our case for both catalysts TiO2 and ZnO. A comparative study of the photocatalytic degradation showed that these two catalysts have a comparable reactivity; it follows a pseudo-first-order kinetics. The degradation trends followed the order: UV365/Fenton > UV365/TiO2 > Solar Fenton > Solar TiO2 > Fenton ~UV365/ZnO. Among AOPs, processes using Fenton type reagent are relatively cheap and easy to operate and maintain. Moreover, UV365/Fenton process has been shown as effective in the treatment of OG dye. Dye was degraded following second-order kinetics. The rate constants was 0,041 .10+6 L.M-1.min-1. The degradation was followed by spectrophotometric method, chemical oxygen demand (COD) measures and high performance liquid chromatography analyses (HPLC). Some aromatic and aliphatic degradation compounds were identified. Degradation of Orange G by UV Fenton mechanism was also proposed.

Keywords: AOPs, homogeneous catalysis, heterogeneous catalysis, acid orange 10, hydroxyl radical

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

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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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Authors: Haneef Ur Rehman, Afsheen Aman, Abdul Hameed Baloch, Shah Ali Ul Qader

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Pectinase is a heterogeneous group of enzymes that catalyze the hydrolysis of pectin substances and widely has been used in food and textile industries. In current study, pectinase from B. licheniformis KIBGE-IB21 was immobilized within different polymers (calcium alginate beads, polyacrylamide gel and agar-agar matrix) to enhance its catalytic properties. Polyacrylamide gel was found to be most promising one and gave maximum (89%) immobilization yield. While less immobilization yield was observed in case of calcium alginate beads that only retained 46 % activity. The reaction time for maximum pectinolytic activity was increased from 5.0 to 10 minutes after immobilization. The temperature of pectinase for maximum enzyme activity was increased from 45 °C to 50 °C and 55 °C when it was immobilized within agar-agar and calcium alginate beads, respectively. The optimum pH of pectinase didn’t alter when it was immobilized within polyacrylamide gel and calcium alginate beads, but in case of agar-agar it was changed from pH 10 to pH 9.0. Thermal stability of pectinase was improved after immobilization and immobilized pectinase showed higher toleration against different temperatures as compared to free enzyme. It can be concluded that the entrapment is a simple, single step and promising procedure to immobilized pectinase within different synthetic and non-synthetic polymers and enhanced its catalytic properties.

Keywords: pectinase, characterization immobilization, polyacrylamide, agar-agar, calcium alginate beads

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Authors: Fatima Zohra Ibn Majdoub Hassani, Ivan Lavandera, Joseph Kreit

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This study explored the effects of different organic solvents, temperature, and the amount of glycerol on the alcohol dehydrogenase (ADH)-catalysed stereoselective reduction of different ketones. These conversions were then analyzed by gas chromatography. It was found that when the amount of deep eutectic solvents (DES) increases, it can improve the stereoselectivity of the enzyme although reducing its ability to convert the substrate into the corresponding alcohol. Moreover, glycerol was found to have a strong stabilizing effect on the ADH from Ralstonia sp. (E. coli/ RasADH). In the case of organic solvents, it was observed that the best conversions into the alcohols were achieved with DMSO and hexane. It was also observed that temperature decreased the ability of the enzyme to convert the substrates into the products and also affected the selectivity. In addition to that, the recycling of DES up to three times gave good conversions and enantiomeric excess results and glycerol showed a positive effect in the stability of various ADHs. Using RasADH, a good conversion and enantiomeric excess into the S-alcohol were obtained. It was found that an enhancement of the temperature disabled the stabilizing effect of glycerol and decreased the stereoselectivity of the enzyme. However, for other ADHs a temperature increase had an opposite positive effect, especially with ADH-T from Thermoanaerobium sp. One of the objectives of this study was to see the effect of cofactors such as NAD(P) on the biocatlysis activities of ADHs.

Keywords: alcohol dehydrogenases, DES, gas chromatography, RasADH

Procedia PDF Downloads 193

Authors: Salem Abdalla

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Objective: Dipyrone is a widely used, well tolerated analgesic drug which, however, is compromised by agranulocytosis as an adverse effect. Subsequent to no enzymatic hydrolysis, the primary metabolic step is N-demethylation of 4-methylaminoantipyrine (4-MAA) to 4-aminoantipyrine (4-AA). The aim of the present study was to identify the cytochrome P-450 enzyme (CYP) mediating this reaction. Methods: We identified the relevant CYP using virus expressed isolated rat liver microsomes with chemical inhibition studies. The substrate of 4-methylaminantipyrine was employed at six different concentrations (25, 50, 100, 400, 800, and 1200 µmol/l) with varying concentrations of selective inhibitors of CYP1A2 (furafylline, fluvoxamine), CYP3A4 (ketoconazole), CYP2A6 (coumarin), CYP2D6 (quinidine), CYP2C19 (omeprazole, fluvoxamine, tranylcypromine), CYP2C9 (sulfaphenazole), and CYP1A1 (alpha-naphthoflavone). 4-MAA and 4-AA were analyzed by HPLC, and enzyme kinetic parameters (Km and Vmax) were determined by regression (Sigma plot 9.0). Results: The N-demethylation of 4-MAA by microsomes prepared from baculovirus-expressing human CYP was pronounced with CYP2C19. Intrinsic clearances of the most active enzymes were 0.092, 0.027, and 0.026 for the CYP enzymes 2C19, 2D6, and 1A2, respectively. Metabolism by rat liver microsomes was strongly inhibited by omeprazole (IC50 of 0.05). Conclusion: The enzyme CYP2C19 apparently has an important role in N-demethylation of 4-methylaminoantipyrine which should be further analyzed in clinical studies and which may also be interesting concerning the agranulocytosis.

Keywords: dipyrone, 4-methylaminoantipyrine (4-MAA), 4- aminoantipyrine (4-AA), metabolism, human CYP2C19

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Authors: Hina Gul Rajpoot, Wazeer Hussain Solangi

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Experimental Design (DOE) economically maximizes information; we deliberately change one or more process variables (looms) in order to observe the effect the changes have on one or more response fabric properties. In DOE obtained data can be analyzed to yield valid and objective conclusions. An Experimental Design is lying out of a detailed experimental plan in advance and maximizes the amount of "information" that can be obtained for a given amount of experimental. Fabric of 36 inches having following weaves was used. 3/1 twill, warp cotton (10.5 den), weft Lycra (16 spandex * 70 den) Ends per inch86, Picks per inch 52 and washes process includes Stone wash, Rinse wash, Bleaching and Enzyme wash. Once the samples were ready, they were subjected to tensile and tear strength tests, for these two kinds of samples were considered. One washed fabric samples of warp direction type and other type of the samples was weft direction. Then five samples from each were considered for tensile and teat strength tests separately then takes the mean value. The results found that the lowest strength damaged in the weft direction observed by tensile strength test & Enzyme wash. Maximum breaking load of the enzyme washed fabric sample was 42 kg.

Keywords: twill, indigo dye, tear strength, loom, ball warp, denier or den, seam, waist band, pilling, selvage

Procedia PDF Downloads 271

Authors: Ji Hye Im, Nguyen T. T. Phuong, Keon Wook Kang

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Estrogens are important for the development and growth of estrogen receptor (ER)-positive breast cancer, for which anti-estrogen therapy is one of the most effective treatments. However, its efficacy can be limited by either de novo or acquired resistance. Aromatase is a key enzyme for the biosynthesis of estrogens, and inhibition of this enzyme leads to profound hypoestrogenism. Here, we found that the basal expression and activity of aromatase were significantly increased in tamoxifen (TAM)-resistant human breast cancer (TAMR-MCF-7) cells compared to control MCF-7 cells. We further revealed that aromatase immunoreactivity in tumor tissues was increased in recurrence group after TAM therapy compared to non-recurrence group after TAM therapy. Phosphorylation of Akt, extracellular signal-regulated kinase (ERK), and p38 kinase were all increased in TAMR-MCF-7 cells. Inhibition of phosphoinositide 3-kinase (PI3K) suppressed the transactivation of the aromatase gene and its enzyme activity. Furthermore, we have also shown that PI3K/Akt-dependent cAMP-response element binding protein (CREB) activation was required for the enhanced expression of aromatase in TAMR-MCF-7 cells. Our findings suggest that aromatase expression is up-regulated in TAM-resistant breast cancer via PI3K/Akt-dependent CREB activation.

Keywords: TAMR-MCF-7, CREB, estrogen receptor, aromatase

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Authors: Ashok K. Gupta

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Over the past few decades, since the bio-engineering revolution, autologous cell therapy (ACT) has become a rapidly evolving field. Currently, this form of therapy has broad applications in modern medicine and plastic surgery, ranging from the treatment/improvement of wound healing to life-saving operations. A study was conducted on 50 patients having to disfigure, and deform post burn scars and was treated by injection of extracted, refined adipose tissue grafts with their unique stem cell properties. To compare the outcome, a control of 20 such patients was treated with conventional skin or soft-tissue flaps or skin grafting, and a control of 10 was treated with more advanced microsurgical techniques such as Pre-fabricated flaps/pre laminated flaps / free flaps. Assessment of fat volume and survival post- follow up period was done by radiological aid, using MRI and clinically (Survival of the autograft and objective parameters for scar elasticity were evaluated skin elasticity parameters 3 to 9 months postoperatively). Recently, an enzyme that is involved in collagen crosslinking in fibrotic tissue, lysyl hydroxylase (LH2), was identified. This enzyme is normally active in bone and cartilage but hardly in the skin. It has been found that this enzyme is highly expressed in scar tissue and subcutaneous fat; this is in contrast to the dermis, where the enzyme is hardly expressed. Adipose tissue-derived stem cell injections are an effective method in the treatment of various extensive post-burn scar deformities that makes it possible to re-create the lost sub-dermal tissue for improvement in the function of involved joint movements.

Keywords: adipose tissue-derived stem cell injections, treatment of various extensive post-burn scar deformities, re-create the lost sub-dermal tissue, improvement in function of involved joint movements

Procedia PDF Downloads 67

Authors: Md. Z. Alam, Amal A. Elgharbawy, Muhammad Moniruzzaman, Nassereldeen A. Kabbashi, Parveen Jamal

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The enzymatic hydrolysis of lignocellulosic biomass is one of the obstacles in the process of sugar production, due to the presence of lignin that protects the cellulose molecules against cellulases. Although the pretreatment of lignocellulose in ionic liquid (IL) system has been receiving a lot of interest; however, it requires IL removal with an anti-solvent in order to proceed with the enzymatic hydrolysis. At this point, introducing a compatible cellulase enzyme seems more efficient in this process. A cellulase enzyme that was produced by Trichoderma reesei on palm kernel cake (PKC) exhibited a promising stability in several ILs. The enzyme called PKC-Cel was tested for its optimum pH and temperature as well as its molecular weight. One among evaluated ILs, 1,3-diethylimidazolium dimethyl phosphate [DEMIM] DMP was applied in this study. Evaluation of six factors was executed in Stat-Ease Design Expert V.9, definitive screening design, which are IL/ buffer ratio, temperature, hydrolysis retention time, biomass loading, cellulase loading and empty fruit bunches (EFB) particle size. According to the obtained data, IL-enzyme system shows the highest sugar concentration at 70 °C, 27 hours, 10% IL-buffer, 35% biomass loading, 60 Units/g cellulase and 200 μm particle size. As concluded from the obtained data, not only the PKC-Cel was stable in the presence of the IL, also it was actually stable at a higher temperature than its optimum one. The reducing sugar obtained was 53.468±4.58 g/L which was equivalent to 0.3055 g reducing sugar/g EFB. This approach opens an insight for more studies in order to understand the actual effect of ILs on cellulases and their interactions in the aqueous system. It could also benefit in an efficient production of bioethanol from lignocellulosic biomass.

Keywords: cellulase, hydrolysis, lignocellulose, pretreatment

Procedia PDF Downloads 365

Authors: Afsheen Aman, Shah Ali Ul Qader

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Dextransucrase [EC 2.4.1.5] is a glucosyltransferase that catalysis the biosynthesis of a natural biopolymer called dextran. It can catalyze the transfer of D-glucopyranosyl residues from sucrose to the main chain of dextran. This unique biopolymer has multiple applications in several industries and the key utilization of dextran lies on its molecular weight and the type of branching. Extracellular dextransucrase from Leuconostoc mesenteroides is most extensively studied and characterized. Limited data is available regarding cell-bound or intracellular dextransucrase and on the characterization of dextran produced by in-vitro reaction of intracellular dextransucrase. L. mesenteroides AA1 is reported to produce extracellular dextransucrase that catalyzes biosynthesis of a high molecular weight dextran with only α-(1→6) linkage. Current study deals with the characterization of an intracellular dextransucrase and in vitro biosynthesis of low molecular weight dextran from L. mesenteroides AA1. Intracellular dextransucrase was extracted from cytoplasm and purified to homogeneity for characterization. Kinetic constants, molecular weight and N-terminal sequence analysis of intracellular dextransucrase reveal unique variation with previously reported extracellular dextransucrase from the same strain. In vitro synthesized biopolymer was characterized using NMR spectroscopic techniques. Intracellular dextransucrase exhibited Vmax and Km values of 130.8 DSU ml-1 hr-1 and 221.3 mM, respectively. Optimum catalytic activity was detected at 35°C in 0.15 M citrate phosphate buffer (pH-5.5) in 05 minutes. Molecular mass of purified intracellular dextransucrase is approximately 220.0 kDa on SDS-PAGE. N-terminal sequence of the intracellular enzyme is: GLPGYFGVN that showed no homology with previously reported sequence for the extracellular dextransucrase. This intracellular dextransucrase is capable of in vitro synthesis of dextran under specific conditions. This intracellular dextransucrase is capable of in vitro synthesis of dextran under specific conditions and this biopolymer can be hydrolyzed into different molecular weight fractions for various applications.

Keywords: characterization, dextran, dextransucrase, leuconostoc mesenteroides

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Authors: Frieda Eivazi, Nikita L. Mullings

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Soils are recipient for surfactants in herbicide formulations. Surfactants entering the soil environment can possibly disrupt different chemical, physical and biological interactions. Therefore, it is critical that we understand the fate, behavior and transport of surfactants upon entering the soil. A comprehensive study was conducted to examine effect of surfactants on nutrient uptake, microbial community, and enzyme activity. The research was conducted in the greenhouse growing corn (Zea mays) as a test plant in a factorial experiment (three surfactants at two different rates with control, and three herbicides) organized as randomized blocked design. Surfactants evaluated were Activator 90, Agri-Dex, and Thrust; herbicides were glyphosate, atrazine, and bentazon. Treatments examined were surfactant only, herbicide only, and surfactant + herbicide combinations. Corn was planted in fertilized soils (silt loam and silty clay) with moisture content maintained at the field capacity for optimum growth. This paper will report results of above mentioned treatments on acid phosphatase, beta-glucosidase, arylsulfatase, beta-glucosaminidase, and dehydrogenase activities. In general, there were variations in the enzyme activities with some inhibition and some being enhanced by the treatments. Activator 90 appeared to have the highest inhibitory effect on enzymatic activities. Atrazine application significantly decreased the activities of acid phosphatase, beta-glucosidase, and dehydrogenase in both soils; however, combination of Atrazine + Agridex increased the acid phosphatase activity while significantly inhibiting the other enzyme activities in soils. It was concluded that long-term field studies are needed to validate changes in nutrient uptake, microbial community and enzyme activities due to surfactant-herbicide combination effects.

Keywords: herbicides, nutrient cycling, soil enzymes, surfactant

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Authors: Mallika Supa-Aksorn, Buaream Maneewan, Jiraporn Rojtinnakorn

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For animals, trypsin and chymotrypsin are the 2 proteases that play the important role in protein digestion and involving in growth rate. In many animals, these two enzymes are indicated as growth parameter by feed. Although enzyme assay at optimal condition is significant for its accuracy activity determination. There is less report of trypsin and chymotrypsin. Therefore, in this study, optimization of pH and temperature for trypsin (T) and chymotrypsin (C) in economic species; i.e. Nile tilapia (Oreochromis niloticus), sand goby (Oxyeleotoris marmoratus), giant freshwater prawn (Macrobachium rosenberchii) and native chicken (Gallus gallus) were investigated. Each enzyme of each species was assaying for its specific activity with variation of pH in range of 2-12 and temperature in range of 30-80 °C. It revealed that, for Nile tilapia, T had optimal condition at pH 9 and temperature 50-80 °C, whereas C had optimal condition at pH 8 and temperature 60 °C. For sand goby, T had optimal condition at pH 7 and temperature of 50 °C, while C had optimal condition at pH 11 and temperature of 70-75 °C. For juvenile freshwater prawn, T had optimal condition at pH 10-11 and temperature of 60-65 °C, C had optimal condition at pH 8 and temperature of 70°C. For starter native chicken, T has optimal condition at pH 7 and temperature of 70 °C, whereas C had o optimal condition at pH 8 and temperature of 60°C. This information of optimal conditions will be high valuable in further for, actual enzyme measurement of T and C activities that benefit for growth and feed analysis.

Keywords: trypsin, chymotrypsin, Oreochromis niloticus, Oxyeleotoris marmoratus, Macrobachium rosenberchii, Gallus gallus

Procedia PDF Downloads 259

Authors: Charles Kwasi Antwi, Mohammad Naushad Emmambux, Natalia Rosa-Sibakov

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The consumption of high-fibre snacks is beneficial in reducing the prevalence of most non-communicable diseases and improving human health. However, using high-fibre flour to produce snacks by extrusion cooking reduces the expansion ratio of snacks, thereby decreasing sensory properties and consumer acceptability of the snack. The study determines the effects of adding Viscozyme®-treated sorghum bran on the properties of extruded sorghum snacks with the aim of producing high-fibre expanded snacks with acceptable quality. With a twin-screw extruder, sorghum endosperm flour [by decortication] with and without sorghum bran and with enzyme-treated sorghum bran was extruded at high shear rates with feed moisture of 20%, feed rate of 10 kg/hr, screw speed of 500 rpm, and temperature zones of 60°C, 70°C, 80°C, 140°C, and 140°C toward the die. The expanded snacks that resulted from this process were analysed in terms of their physical (expansion ratio, bulk density, colour profile), chemical (soluble and insoluble dietary fibre), and functional (water solubility index (WSI) and water absorption index (WAI)) characteristics. The expanded snacks produced from refined sorghum flour enriched with Viscozyme-treated bran had similar expansion ratios to refined sorghum flour extrudates, which were higher than those for untreated bran-sorghum extrudate. Sorghum extrudates without bran showed higher values of expansion ratio and low values of bulk density compared to the untreated bran extrudates. The enzyme-treated fibre increased the expansion ratio significantly with low bulk density values compared to untreated bran. Compared to untreated bran extrudates, WSI values in enzyme-treated samples increased, while WAI values decreased. Enzyme treatment of bran reduced particle size and increased soluble dietary fibre to increase expansion. Lower particle size suggests less interference with bubble formation at the die. Viscozyme-treated bran-sorghum composite flour could be used as raw material to produce high-fibre expanded snacks with improved physicochemical and functional properties.

Keywords: extrusion, sorghum bran, decortication, expanded snacks

Procedia PDF Downloads 92

Authors: Wen-Shyong Tzou, Chih-Ching Huang, Chin-Hwa Hu, Ying-Tsang Lo, Tun-Wen Pai, Chia-Yin Chiang, Chung-Hao Li, Hong-Jyuan Jian

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Plasmin plays an important role in the human circulatory system owing to its catalytic ability of fibrinolysis. The immediate injection of plasmin in patients of strokes has intrigued many scientists to design vectors that can transport plasmin to the desired location in human body. Here we predict the structure of human plasmin and investigate the interaction of plasmin with the gold-nanoparticle. Because the crystal structure of plasminogen has been solved, we deleted N-terminal domain (Pan-apple domain) of plasminogen and generate a mimic of the active form of this enzyme (plasmin). We conducted a simulated annealing process on plasmin and discovered a very large conformation occurs. Kringle domains 1, 4 and 5 had been observed to leave its original location relative to the main body of the enzyme and the original doughnut shape of this enzyme has been transformed to a V-shaped by opening its two arms. This observation of conformational change is consistent with the experimental results of neutron scattering and centrifugation. We subsequently docked the plasmin on the simulated gold surface to predict their interaction. The V-shaped plasmin could utilize its Kringle domain and catalytic domain to contact the gold surface. Our findings not only reveal the flexibility of plasmin structure but also provide a guide for the design of a plasmin-gold nanoparticle.

Keywords: docking, gold nanoparticle, molecular simulation, plasmin

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Authors: M. Umar Dahot, G. S. Mangrio

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In this study Agro-industrial waste was used as a carbon source, which is a low cost substrate. Along with this, various sugars and molasses of 2.5% and 5% were investigated as substrate/carbon source for the growth of A.niger and Pectinase production. Different nitrogen sources were also used. An overview of results obtained show that 5% sucrose, 5% molasses and 0.4% (NH4)2SO4 were found the best carbon and nitrogen sources for the production of pectinase by A. niger. The maximum production of pectinase (26.87units/ml) was observed at pH 6.0 after 72 hrs incubation. The optimum temperature for the maximum production of pectinase was achieved at 35ºC when maximum production of pectinase was obtained as 28.25Units/ml.Pectinase enzyme was purified with ammonium sulphate precipitation and dialyzed sample was finally applied on gel filtration chromatography (Sephadex G-100) and Ion Exchange DEAE A-50. The enzyme was purified 2.5 fold by gel chromatography on Sephadex G-100 and Four fractions were obtained, Fraction 1, 2, 4 showed single band while Fraction -3 showed multiple bands on SDS Page electrophoresis. Fraction -3 was pooled, dialyzed and separated on Sephdex A-50 and two fractions 3a and 3b showed single band. The molecular weights of the purified fractions were detected in the range of 33000 ± 2000 and 38000± 2000 Daltons. The purified enzyme was specifically most active with pure pectin, while pectin, Lemon pectin and orange peel given lower activity as compared to (control). The optimum pH and temperature for pectinase activity was found between pH 5.0 and 6.0 and 40°- 50°C, respectively. The enzyme was stable over the pH range 3.0-8.0. The thermostability of was determined and it was observed that the pectinase activity is heat stable and retains activity more than 40% when incubated at 90°C for 10 minutes. The pectinase activity of F3a and F3b was increased with different metal ions. The Pectinase activity was stimulated in the presence of CaCl2 up to 10-30%. ZnSO4, MnSO4 and Mg SO4 showed higher activity in fractions F3a and F3b, which indicates that the pectinase belongs to metalo-enzymes. It is concluded that A. niger is capable to produce pH stable and thermostable pectinase, which can be used for industrial purposes.

Keywords: pectinase, a. niger, production, purification, characterization

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Authors: Zh. Saffari, A. Naeimi, M. S. Ekrami-Kakhki, F. Hamidi

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Fe3O4 is one of the important magnetic oxides with spinel structure; it has exhibited unique electric and magnetic properties based on the electron transfer between Fe2+ and Fe3+ in the octahedral sites. Fe3O4 has received considerable attention in various areas such as cancer therapy, drug targeting, enzyme immobilization catalysis, magnetic cell separation, magnetic refrigeration systems and super-paramagnetic materials Fe3O4–TiO2 nanostructures were synthesized by simple, effective and new co-precipitation method assisted by ultrasonic reaction at room temperatures with organic surfactant. The effect of various parameters such as temperature, time, and power on the size and morphology of the product was investigated. Alternating gradient force magnetometer shows that Fe3O4 nanoparticles exhibit super-paramagnetic behaviour at room temperature. For preparation of nanocomposite, 1 g of TiO2 nanostructures were dispersed in 100 mL of ethanol. 0.25 g of Fe(NO3)2 and 2 mL of octanoic acid was added to the solution as a surfactant. Then, NaOH solution (1.5 M) was slowly added into the solution until the pH of the mixture was 7–8. After complete precipitation, the solution placed under the ultrasonic irradiation for 30 min. The product was centrifuged, washed with distilled water and dried in an oven at 100 °C for 3 h. The resulting red powder was calcinated at 800 °C for 3 h to remove any organic residue. The photocatalytic behaviour of Fe3O4–TiO2 nanoparticles was evaluated using the degradation of a Methyl Violet (MV) aqueous solution under ultraviolet light irradiation. As time increased, more and more MV was adsorbed on the nanoparticles catalyst, until the absorption peak vanish. The MV concentration decreased rapidly with increasing UV-irradiation time

Keywords: magnetic, methyl violet, nanocomposite, photocatalytic

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Authors: Zhanara Suleimenova, Raushan Blieva, Aigerim Zhakipbekova, Inkar Tapenbayeva, Zhanar Narmuratova

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Green processes are based on innovative technologies that do not negatively affect the environment. Industrial enzymes originated from biological systems can effectively contribute to sustainable development through being isolated from microorganisms which are fermented using primarily renewable resources. Many widespread microorganisms secrete a significant amount of biocatalysts into the environment, which greatly facilitates the task of their isolation and purification. The ability to control the enzyme production through the regulation of their biosynthesis and the selection of nutrient media and cultivation conditions allows not only to increase the yield of enzymes but also to obtain enzymes with certain properties. In this regard, large potentialities are embedded in immobilized cells. Enzyme production technology in a secreted active form enabling industrial application on an economically feasible scale has been developed. This method is based on the immobilization of enzyme producers on a solid career. Immobilizing has a range of advantages: decreasing the price of the final product, absence of foreign substances, controlled process of enzyme-genesis, the ability of various enzymes' simultaneous production, etc. Design of proposed equipment gives the opportunity to increase the activity of immobilized cell culture filtrate comparing to free cells, growing in periodic culture conditions. Such technology allows giving a 10-times raise in culture productivity, to prolong the process of fungi cultivation and periods of active culture liquid generation. Also, it gives the way to improve the quality of filtrates (to make them more clear) and exclude time-consuming processes of recharging fermentative vials, that require manual removing of mycelium.

Keywords: industrial enzymes, immobilization, submerged fermentation, microscopic fungi

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Authors: Palwinder Singh

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Beyond the conventional mode of working with anti-inflammatory agents through enzyme inhibition, herein, an alternate substrate of cyclooxygenase-2 was developed. Proline centered pentapeptide iso-conformational to arachidonic acid exhibited appreciable selectivity for COX-2 overcoming acetic acid and formalin induced pain in rats to almost 80% and was treated as a substrate by the enzyme. Remarkably, COX-2 metabolized the pentapeptide into small fragments consisting mainly of di- and tri-peptides that ensured the safe breakdown of the peptide under in-vivo conditions. The kinetic parameter Kcat/Km for COX-2 mediated metabolism of peptide 6.3 x 105 M-1 s-1 was quite similar to 9.5 x 105 M-1 s-1 for arachidonic acid. Evidenced by the dynamic molecular studies and the use of Y385F COX-2, it was observed that the breakage of the pentapeptide has probably taken place through H-bond activation of the peptide bond by the side chains of Y385 and S530.

Keywords: small peptides, anti-inflammatory agents, cyclooxygenase-2, unnatural substrates

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Authors: Eleftheria Barouni, Theano Petsi, Argyro Bekatorou, Dionysos Kolliopoulos, Dimitrios Vasileiou, Panayiotis Panas, Maria Kanellaki, Athanasios A. Koutinas

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The aim of the present work was the production and use of a composite filter (TC/starch), containing rennin enzyme, in continuous system and in successive fermentation batches (SFB) for milk coagulation in order to compare the operational stability of both systems and cheese production cost. Tubular cellulose (TC) was produced after removal of lignin from lignocellulosic biomass using several procedures, e.g. alkaline treatment [1] and starch gel was added for the reduction of TC tubes dimensions to micro- and nano- range[2]. Four immobilized biocatalysts were prepared using different ways of the enzyme entrapment. 1) TC/ rennin (rennin entrapped in the tubes of TC), 2) TC/SG-rennin (rennin entrapped in the tubes of the composite), 3) TC-SG/rennin (rennin entrapped into the layer of starch gel) and 4) TC/rennin- SG/rennin (rennin is entrapped both in the tubes of the TC and into the layer of starch gel). Firstly these immobilized biocatalysts were examined in ten SFB regarding the coagulation time and their activity All the above immobilized biocatalysts remained active and the coagulation time was ranged from 90 to 480, 120-480, 330-510, and 270-540 min for (1), (2), (3), and (4) respectively. The quality of the cheese was examined through the determination of volatile compounds by SPME GC/MS analysis. These results encouraged us to study a continuous coagulation system of milk. Even though the (1) immobilized biocatalyst gave lower coagulation time, we used the (2) immobilized biocatalyst in the continuous system. The results were promising.

Keywords: tubular cellulose, starch gel, composite biocatalyst, Rennin, milk coagulation

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Authors: Kazam Ali, Muhammad Sagheer, Mansoor-Ul- Hasan, Abdul Rashid, Chaudhary Muhammad Shahid Hanif, Fawad Zafar Ahmad Khan, Hafiz Muhammad Aatif

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Natural extracts of two medicinal plants Nicotiana tabacum and Eucalyptus globulus were tested for their toxic and enzyme inhibition effects against three insects species of stored grains Tribolium castaneum, Trogoderma granarium and Sitophilus granarius. Responses of insects varied with exposure periods and dilution levels of acetone extracts of plants. Both plant extracts were lethal to insects but the crude leaf extract of N. tabacum evidenced strong toxic action against three tested insect species. Maximum mortality 36.30% in S. granarius, 25.96% in T. castaneum, and 21.88% in T. granarium were found at 20% dilution level, after 10 days exposure to botanical extract of N. tabacum. The impact of N. tabacum and E. globulus on the activity of esterases; acetylcholinesterase (AChE), α-carboxylesterase (α-CE), β-carboxylesterase (β-CE) and phosphatses; acid phosphatase (AcP), alkaline phosphatase (AlP) of three stored grain insect species were also studied in the survivors of toxicity assay. Whole body homogenates of insects were used for enzyme determination and consumption of high dose rate N. tabacum extract containing diet resulted in maximum 55.33% inhibition of AChE and 26.17% AlP inhibition in T. castaneum, while 44.17% of α-CE and 31.67% inhibition of β-CE activity were noted in S. granarius. Maximum inhibition 23.44% of AcP activity was found in T. granarium exposed to diet treated with the extract of E. globulus. The findings indicate that acetone extracts of N. tabacum and E. globulus are naturally occurring pesticide and facts of the enzyme inhibition relations specify that their effect changes with the insect species.

Keywords: natural extract, medicinal plant, toxic effects, enzyme inhibition, acetone extract

Procedia PDF Downloads 258

Authors: Kabrambam D. Singh, Dinabandhu Sahoo, Yallappa Rajashekar

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Evolution has caused many insects to develop resistance to several synthetic insecticides. This problem along with the persisting concern regarding the health and environmental safety issues of the existing synthetic insecticides has urged the scientific fraternity to look for a new plant-based natural insecticide with inherent eco-friendly nature. Colocasia esculenta var. esculenta (L.) Schott (Araceae family) is widely grown throughout the South- East Asian Countries for its edible corms and leaves. Various physico-chemical and spectroscopic techniques (IR, 1H NMR, 13C NMR and Mass) were used for the isolation and characterization of isolated bioactive molecule named 2, 3-dimethylmaleic anhydride (3, 4-dimethyl-2, 5-furandione). This compound was found to be highly toxic, even at low concentration, against several storage grain pests when used as biofumigant. Experimental studies on the mode of action of 2, 3-dimethylmaleic anhydride revealed that the biofumigant act as inhibitor of acetylcholinesterase enzyme in cockroach and stored grain insects. The knockdown activity of bioactive compound is concurrent with in vivo inhibition of AChE; at KD99 dosage of bioactive molecule showed more than 90% inhibition of AChE activity in test insects. The molecule proved to affect the antioxidant enzyme system; superoxide dismutase (SOD), and catalase (CAT) and also found to decrease reduced glutathione (GSH) level in the treated insects. The above results indicate involvement of inhibition of AChE activity and oxidative imbalance as the potential mode of action of 2, 3-dimethylmaleic anhydride. In addition, the study reveals computational docking programs elaborate the possible interaction of 2, 3-dimethylmaleic anhydride with enzyme acetylcholinesterase (AChE) of Periplaneta americana. Finally, the results represent that toxicity of 2, 3-dimethylmaleic anhydride might be associated with inhibition of AChE activity and oxidative imbalance.

Keywords: 2, 3-dimethylmaleic anhydride, Colocasia esculenta var. esculenta (L.) Schott, Biofumigant, acetylcholinesterase, antioxidant enzyme, molecular docking

Procedia PDF Downloads 160

Authors: Neha Sharma, Kanthi K. Kondepudi, Naveen Gupta

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Phytases are phytate specific phosphatases catalyzing the step-wise dephosphorylation of phytate, which acts as an anti-nutritional factor in food due to its strong binding capacity to minerals. In recent years microbial phytases have been explored for improving nutritional quality of food. But the major limitation is acceptability of phytases from these microorganisms. Therefore, efforts are being made to isolate organisms which are generally regarded as safe for human consumption such as Lactic Acid Bacteria (LAB). Phytases from these organisms will have an edge over other phytase sources due to its probiotic attributes. Only few LAB have been reported to give phytase activity that too is generally seen as intracellular. LAB producing extracellular phytase will be more useful as it can degrade phytate more effectively. Moreover, enzyme from such isolate will have application in food processing also. Only few species of Lactobacillus producing extracellular phytase have been reported so far. This study reports the isolation of a probiotic strain of Lactobacillus fermentum spp KA1 which produces extracellular phytase. Conditions for the optimal production of phytase have been optimized and the enzyme production resulted in an approximately 13-fold increase in yield. The phytate degradation potential of extracellular phytase in rice bran has been explored and conditions for optimal degradation were optimized. Under optimal conditions, there was 43.26% release of inorganic phosphate and 6.45% decrease of phytate content.

Keywords: Lactobacillus, phytase, phytate reduction, rice bran

Procedia PDF Downloads 198

Authors: Akmuhammet Karayev, Hassam Mazhar, Mamdouh Al Harthi

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Polyethylene terephthalate (PET) recycling stands as a pivotal solution in combating plastic pollution and fostering a circular economy. This study addresses the catalytic glycolysis of PET, a key step in its recycling process, using synthesized catalysts. Our focus lies in elucidating the catalytic mechanism, optimizing reaction kinetics, and enhancing reactor design for efficient PET conversion. We synthesized anionic clays tailored for PET glycolysis and comprehensively characterized them using XRD, FT-IR, BET, DSC, and TGA techniques, confirming their suitability as catalysts. Through systematic parametric studies, we optimized reaction conditions to achieve complete PET conversion to bis hydroxy ethylene terephthalate (BHET) with over 75% yield within 2 hours at 200°C, employing a minimal catalyst concentration of 0.5%. These results underscore the catalysts' exceptional efficiency and sustainability, positioning them as frontrunners in catalyzing PET recycling processes. Furthermore, we demonstrated the recyclability of the obtained BHETs by repolymerizing them back to PET without the need for a catalyst. Heating the BHETs in a distillation unit facilitated their conversion back to PET, highlighting the closed-loop potential of our recycling approach. Our work embodies a significant leap in catalytic glycolysis kinetics, driven by sustainable catalysts, offering rapid and high-impact PET conversion while minimizing environmental footprint. This breakthrough not only sets new benchmarks for efficiency in PET recycling but also exemplifies the pivotal role of catalysis and reaction engineering in advancing sustainable materials management.

Keywords: polymer recycling, catalysis, circular economy, glycolysis

Procedia PDF Downloads 41

Authors: Amin Akhnoukh, Halla Elea, Lawrence Benzmiller

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The objective of this research is to evaluate the possibility of using nano-sized materials, mainly titanium dioxide (TiO2), in producing economic self-cleaning concrete using photo-catalysis process. In photo-catalysis, the nano-particles react and dissolve smog, dust, and dirt particles in the presence of sunlight, resulting in a cleaned concrete surface. To-date, the Italian cement company (Italcementi) produces a proprietary self-cleaning cementitious material that is currently used in government buildings and major highways in Europe. The high initial cost of the proprietary product represents a major obstacle to the wide spread of the self-cleaning concrete in industrial and commercial projects. In this research project, titanium dioxide nano-sized particles are infused to the top layer of a concrete pour before the concrete surface is finished. Once hardened, a blue dye is applied to the concrete surface to simulate smog and dirt effect. The concrete surface is subjected to direct light to investigate the effectiveness of the nano-sized titanium dioxide in cleaning the concrete surface. The outcome of this research project proved that the titanium dioxide can be successfully used in reducing smog and dirt particles attached to the concrete when infused to the surface concrete layer. The majority of cleansing effect due to photocatalysis happens within 24 hours of photocatalysis process. The non-proprietary mix can be used in highway, industrial, and commercial projects due to its economy and ease of production.

Keywords: self-cleaning concrete, photocatalysis, Smog-eating concrete, titanium dioxide

Procedia PDF Downloads 354

Authors: Ieva Gaide, Violeta Makareviciene

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Increasing environmental pollution is caused by various factors, including the usage of vehicles. Legislation is focused on the increased usage of renewable energy sources for fuel production. Electric car usage is also important; however, it is relatively new and expensive transport. It is necessary to increase the amount of renewable energy in the production of diesel fuel, whereas many agricultural machineries are powered by diesel, as are water vehicles. For this reason, research on biodiesel production is relevant. The majority of studies globally are related to the improvement of conventional biofuel production technologies by applying the transesterification process of oil using alcohol and catalyst. Some of the more recent methods to produce biodiesel are based on heterogeneous catalysis, which has the advantage of easy separation of catalyst from the final product. It is known that a large amount of eggshells is treated as waste; therefore, it is eliminated in landfills without any or with minimal pre-treatment. CaO, which is known as a good catalyst for biodiesel synthesis, is a key component of eggshells. In the present work, we evaluated the catalytic efficiency of eggshells and determined the optimal transesterification conditions to obtain biodiesel that meets the standards. Content CaO in eggshells was investigated. Response surface methodology was used to determine the optimal reaction conditions. Three independent variables were investigated: the molar ratio of alcohol to oil, the amount of the catalyst, and the duration of the reaction. It was obtained that the optimum transesterification conditions when the methanol and eggshells as a heterogeneous catalyst are used and the process temperature is 64°C are the following: the alcohol-to-oil molar ratio 10.93:1, the reaction duration 9.48 h, and the catalyst amount 6.80 wt%. Under these conditions, 97.79 wt% of the ester yield was obtained.

Keywords: heterogeneous catalysis, eggshells, biodiesel, oil

Procedia PDF Downloads 120

Authors: F. Fushai, M.Tekere, M. Masafu, F. Siebrits, A. Kanengoni, F. Nherera

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The effects of dietary fibre source on the histomorphology of the ileal epithelium were examined in growing pigs fed high fibre (242-250 g total dietary fibre kg-1 dry matter) diets fortified with Roxazyme® G2. The control was a standard, low fibre (141 g total dietary fibre kg-1 dry matter) diet formulated from dehulled soybean (Glycine max), maize (Zea Mays) meal and hominy chop. Five fibrous diets were evaluated in which fibre was increased by partial substitution of the grains in the control diet with maize cobs, soybean hulls, barley (Hordeum vulgare L) brewer’s grains, Lucerne (Medicago sativa) hay or wheat (Triticum aestivum) bran. Each diet was duplicated and 220 mg Roxazyme® G2 kg-1 dry mater was added to one of the mixtures. Seventy-two intact Large White X Landrace male pigs of weight 32 ± 5.6 kg pigs were randomly allocated to the diets in a complete randomised design with a 2 (fibre source) X (enzyme) factorial arrangement of treatments. The pigs were fed ad libitum for 10 weeks. Ileal tissue samples were taken at slaughter, at a point 50cm above the ileal-caecal valve. Villi length and area, and crypt depth were measured by computerised image analyses. The villi length: crypt ratio was calculated. The diet and the supplemental enzyme cocktail did not affect (p>0.05) any of the measured parameters. Significant (p=0.016) diet X enzyme interaction was observed for villi length whereby the enzyme reduced the villi length of pigs on the soy-hulls, standard and wheat bran diets, with an opposite effect on pigs on the maize cob, brewer’s grain, Lucerne diets. The results suggested fibre-source dependent changes in the morphology of the ileal epithelium of pigs fed high fibre, maize-soybean diets fortified with Roxazyme® G2.

Keywords: fibre, growing pigs, histomorphology, ileum, Roxazyme® G2

Procedia PDF Downloads 469

Authors: Yezli-Touiker Samira, Amrani-Kirane Leila, Soltani Mazouni Nadia

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Due to secondary effects of conventional insecticides on the environment, the agrochemical research has resulted in the discovery of novel molecules. That research work will help in the development of a new group of pesticides that may be cheaper and less hazardous to the environment and non-target organisms which is the main desired outcome of the present work. Angiotensin-converting enzyme as a target for the development of novel insect growth regulators. Captopril is an inhibitor of angiotensin converting enzyme (ACE) it was tested in vivo by topical application on reproduction of Ephestia kuehniella Zeller (Lepidoptera: Pyralidae). The compound is diluted in acetone and applied topically to newly emerged pupae (10µg/ 2µl). The effects of this molecule was studied,on the biochemistry of ovary (on amounts nucleic acid, proteins, the qualitative analysis of the ovarian proteins and the reproductive potential (duration of the pre-oviposition, duration of the oviposition, number of eggs laid and hatching percentage). Captopril reduces significantly quantity of ovarian proteins and nucleic acid. The electrophoresis profile reveals the absence of tree bands at the treated series. This molecule reduced the duration of the oviposition period, the fecundity and the eggviability.

Keywords: environment, ephestia kuehniella, captopril, reproduction, the agrochemical research

Procedia PDF Downloads 285

Authors: Munisath Khandoker, Stephan Haefele, Andy Gregory

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Extracellular enzymes play a key role in soil organic carbon (SOC) decomposition and nutrient cycling and are known indicators for soil health; however, it is not understood how these enzymes respond to different land uses and their relationships to other soil properties have not been extensively reviewed. The relationships among the activities of three soil enzymes: β-glucosaminidase (NAG), phosphomonoesterase (PHO) and β-glucosidase (GLU), were examined. The impact of soil organic amendments, soil types and land management on soil enzyme activities were reviewed, and it was hypothesized that soils with increased SOC have increased enzyme activity. Long-term experiments at Rothamsted Research Woburn and Harpenden sites in the UK were used to evaluate how different management practices affect enzyme activity involved in carbon (C) and nitrogen (N) cycling in the soil. Samples were collected from soils with different organic treatments such as straw, farmyard manure (FYM), compost additions, cover crops and permanent grass cover to assess whether SOC can be linked with increased levels of enzymatic activity and what influence, if any, enzymatic activity has on total C and N in the soil. Investigating the interactions of important enzymes with soil characteristics and SOC can help to better understand the health of soils. Studies on long-term experiments with known histories and large datasets can better help with this. SOC tends to decrease during land use changes from natural ecosystems to agricultural systems; therefore, it is imperative that agricultural lands find ways to increase and/or maintain SOC in the soil.

Keywords: biological soil health indicators, extracellular enzymes, soil health, soil, microbiology

Procedia PDF Downloads 72