Salinity endurance of marine macro Rhodophycean algae with special emphasis on myo-inositol biosynthesis: An enzymological analysis from Halymenia venusta Børgesen

Altered salinity is one the most important perils encountered by marine plants inclusive of algae. Under hyper saline condition plants accumulate several stress relieving osmolytes including myo-inositol, the most widespread cyclitol in plants. The present communication reports the occurrence of myo-inositol biosynthesis in six different Rhodophycean seaweeds growing under stressful intertidal habitats of the Okha coast (Gujarat, India), on the basis of a study conducted on two marker enzymes of myo-inositol biosysnthesis [L-myo-inositol-1-phosphate synthase and D/L-myo-inositol-1-phosphate phosphatise]. Both enzymes were partially purified from Halymenia venusta to about 27 and 39 folds respectively over the homogenate following low-speed centrifugation, 30-75% ammonium sulphate fractionation, successive chromatography through DEAE-cellulose / CM-Cellulose, Sephadex G-200 and BioGel 0.5m / UltrogelAcA 34 columns. The temperature and pH optima for both the enzymes were similar and were recorded to be 350C and 7.5 respectively. For MIPS, D-glucose-6-phosphate and NAD were the exclusive substrate and coenzyme respectively and D/L-MIP was the sole substrate for MIPP. The Km values for D-glucsoe-6-phosphate and β-NAD were recorded to be 3.599 mM and 0.2366 mM respectively, while the Km value for D-MIP was found to be 0.4070 mM. Monovalent cations K+ had slight stimulatory, Li+ was strong inhibitory for both the enzymes. Divalent cations Ca2+ exhibited slight stimulatory and Cd2+ reduced MIPS and MIPP activities. MIPP was stimulated by Mg2+. Cu2+ and Hg2+ were strong inhibitors of both the enzymes. A steady and proportionate increase in the content of free myo-inositol was observed along with elevated levels of recorded salinity.

Production and Purification of Amylase from Bacillus subtilis Isolated from Soil

In spite of progress in biotechnology and enzymology, the enzymes have been industrialized in recent years for the mounting up the product development in various arena. The ultimate goal of this study comprises the production and purification the amylase enzyme from the bacterial strain. A powerful amylase producer, Bacillus subtilis ISOLATE-4 was isolated, screened and identified from the soil sample. In order to produce extracellular amylase, various physico-chemical parameters were optimized. During optimization, the maximal production of amylase by the isolate at 48 hrs of incubation in 100 rpm was found to be 6.93U/ml, 5.94U/ml, 6.0U/ml at 45ºC, pH 6 with 1% substrate concentration respectively. Ammonium sulphate fractionation was done for rapid precipitation of the amylase at a concentration of 60% and exposed to dialysis showed the 25% purification fold of an enzyme. The dialyzed product was further subjected to DEAE-Cellulose column chromatography resulted in an increase up to 75% purification fold than crude enzyme. The amylase enzyme might be suitable for the liquefaction of starch, detergent, textile and several additional industrial applications.

Purification and Characterization of Amyloglucosidase Enzyme from the Thermophilic Endomycopsis fibuligera Using Sago Starch as a Substrate

An investigation on purification and characterization of amyloglucosidase enzyme from Endomycopsis fibuligera by fermentation of sago starch has been carried out. This enzyme is inductive and can be produced by fermenting sago starch in a medium containing E. fibuligera. Crude enzyme was obtained by centrifuging the medium cultures containing E. fibuligera at 6,000 rpm for 20 min and then adding with 0.15 M acetate buffer (pH 5.0). Enzyme activity was determined using Somogyi-Nelson method by quantifying the released glucose from amyloglucosidase catalysis of starch (0.2%) as substrate. Prepurification process was conducted by ammonium sulphate fractionation and it showed that the ammonium sulphate fractionation with the degree of saturation of 40-60% produced a maximum activity of enzyme. Purification by DEAE-Cellulose and Sephadex G-75 column chromatography produced three and one fractions with purifity 17.4 and 22.5 times, respectively, compared to the crude extract enzyme. Characterization of this enzyme showed the optimum condition at pH 5.0 and 55 °C with 0.2% starch as substrate. The amyloglucosidase activities was strongly increased by addition of Co2+ and Mn2+ ions, whereas the activities were weakly decreased by addition of K+, Mg2+, and Fe3+ ions.

Studies on the Amylase Inhibitors from the Seeds of Adenanthera Pavonina

ABSTRACT: An α-Amylase inhibitor was isolated and purified employing ammonium sulphate fractionation, molecular sieve chromatography on sephadex G-10 and G-50 and HPLC from the seeds of Adenanthera pavonina. The molecular weight was found to be 10 - 12 kDa as determined by gel-permeation chromatography on Sephadex G-100. The specific inhibitor activity, fold purity and the yield obtained for Adenanthera pavonina amylase inhibitor was 32.12, 51 and 13.07, respectively. The purified inhibitor was heat stable and retained more than 52% activity at 65°C. The optimum pH obtained for purified inhibitor was 6.3 and 100% Zone of inhibition was observed when it was added on the plated organisms. The Adenanthera pavonina amylase inhibitor inhibited the activity of human salivary α-amylase and inhibitory activity of α-amylase inhibitor against mammalian amylases could suggest its potential in treatment of diabetes and related nutritional problems results in obesity.

Protease purification and characterization of a serine protease inhibitor from Egyptian varieties of soybean seeds and its efficacy against Spodoptera littoralis

Serine inhibitors have been described in many plant species and are universal throughout the plant kingdom. Trypsin inhibitors are the most common type. In the present study, trypsin and chymotrypsin inhibitory activity was detected in the seed flour extracts of four Egyptian varieties of soybean (Glycine max). The soybean variety, Giza 22, was found to have higher trypsin and chymotrypsin inhibitory potential compared to other tested soybean varieties. For this reason, Giza 22 was selected for further purification studies which used ammonium sulphate fractionation and DEAE-Sephadex A-25 column. Soybean purified proteins showed a single band on SDS-PAGE corresponding to a molecular mass of 17.9 kDa. The purified inhibitor was stable at temperatures below 60°C and was active at a wide range of pH, from 2 to 12 pH. The kinetic analysis revealed a non-competitive type of inhibition against trypsin and chymotrypsin enzymes. The inhibitor constant (Ki) values suggested that the inhibitor has higher affinity toward a trypsin enzyme than to a chymotrypsin enzyme. Purified inhibitor was found to have deep and negative effects on the mean larval weight, larval mortality, pupation, and mean pupal weight of Spodoptera littoralis. It may be concluded, that soybean protease inhibitor gene(s) could be potential targets for those future studies which are concerned with developing insect resistant transgenic plants

Studies on Interaction of Buffalo Brain Cystatin with Donepezil: An Alzheimer's Drug

When drugs bind to a protein, the intramolecular structures can be altered, resulting in conformational change of the protein. Donepezil, an Acetyl Cholinesterase inhibitor (AChE), is commonly prescribed to patients with Alzheimer's disease (AD) to enhance cholinergic neurotransmission. It is the “first-line” agents in the treatment of Alzheimer's disease used to improve cognitive function in the disease. In the present study, a cysteine protease inhibitor (cystatin) has been isolated from buffalo brain using alkaline treatment, 40 to 60% ammonium sulphate fractionation and gel filtration chromatography on Sephadex G-75 with % yield of 64.13 and fold purification of 384.7. The purified inhibitor (Buffalo Brain Cystatin, (BBC)) was eluted as a single papain inhibitory peak which migrated as single band on native PAGE; however, on SDS-PAGE with and without beta mercaptoethanol (βME) BBC gave two bands of M W 31.6 and 12.4 KDa, respectively. The molecular weight determined by gel filtration came out to be 43.6 KDa. The UV spectra of cystatin on interaction with donepezil suggested a conformational change in the protein. The fluorescence spectra of BC-donepezil composite show structural changes indicating 40 nm red shift with significant increase in fluorescence intensity of cystatin in the presence of donepezil representing an unfolding of cystatin on interaction, which is an indication of side effect of donepezil during the use of this drug.

Purification and Characterization of Tannin Acyl Hydrolase Produced by Mixed Solid State Fermentation of Wheat Bran and Marigold Flower byPenicillium notatumNCIM 923

Tannin acyl hydrolase produced extracellularly by the fungal strainPenicillium notatumNCIM 923 in mixed solid state fermentation of wheat bran and marigold flower in the ratio 4 : 1 was purified from the cell-free extract broth by ammonium sulphate fractionation followed by diethylaminoethyl-cellulose column chromatography. Tannase was purified by 19.89-fold with yield of 11.77%. The specific activity of crude tannase was found to be 1.31 U/mg protein while that of purified tannase was 22.48 U/mg protein. SDS-PAGE analysis indicated that the enzyme is dimeric with one major band of molecular mass 97 kDa and a very light band of molecular mass 43 kDa. Temperature of 35 to 40°C and pH 5 were optimum for tannase activity. The enzyme retained more than 60% of its stability at 60°C and 40% stability at pH 3 and 8, respectively.Kmwas found to be0.33×10-2 M andVmax=40 U/mg. Since the enzyme is active over a wide range of pH and temperature, it could find potential use in the food processing industry.

Pemurnian dan Karakterisasi Enzim Lipase dari Aspergillus oryzae pada Kopra Berjamur

An investigation on purification and characterization of lipase enzyme production Aspergillus oryzae from copra by fermentation of oliveoil has been carried out. This enzyme can be produced by fermenting olive oil in a medium containing Aspergillus oryzae. Crude enzyme isobtained by centrifuging the medium cultures containing Aspergillus oryzae at 3500 rpm for 30 minutes and than adding 0.2 M borat buffer(pH 8.2). Enzyme activity was determined from paranitrophenol as product of lipase catalysis of paranitrophenylbutirat (0.2 M) assubstrate measured by the Vorderwulbecke method. Prepurification process was by ammonium sulphate fractionation. Precipitation60-80% ammonium sulphate produced maximum activity of enzyme. Purification by Q sepharosa FF and sephadex G-75 collumchromatography produced four and three fractions with purifity of 12.85 and 20.25 times than crude enzyme respectively. Characterizationof this enzyme showed optimum condition at pH 8.2, temperature at 350C, the Km value at 0.046 M, and Vmaks is 1.926 μmol/menit and themolecular weight at 40.7 kDa.

Purification and partial biochemical–genetic characterization of trehalose 6-phosphate synthase from muscles of adult femaleAscaris suum

Trehalose 6-phosphate (T6P) synthase (TPS;EC2.4.1.15) was isolated from muscles ofAscaris suumby ammonium sulphate fractionation, ion-exchange DEAE SEPHACELTManion exchanger column chromatography and Sepharose 6B gel filtration. On sodium dodecyl sulphate–polyacrylamide gel electrophoresis (SDS–PAGE), 265-fold purified TPS exhibited a molecular weight of 66 kDa. The optimum pH and temperature of the purified enzyme were 3.8–4.2 and 35°C, respectively. The isoelectric point (pI) of TPS was pH 5.4. The studied TPS was not absolutely substrate specific. Besides glucose 6-phosphate, the enzyme was able to use fructose 6-phosphate as an acceptor of glucose. TPS was activated by 10 mMMgCl2, 10 mMCaCl2and 10 mMNaCl. In addition, it was inhibited by ethylenediaminetetra-acetic acid (EDTA), KCl, FeCl3and ZnCl2. Two genes encoding TPS were isolated and sequenced from muscles of the parasite. Complete coding sequences fortps1(JF412033.2) andtps2(JF412034.2) were 3917 bp and 3976 bp, respectively. Translation products (AEX60788.1 and AEX60787.1) showed expression to the glucosyltransferase-GTB-type superfamily.

Purification and characterization of an exo-polygalacturonase secreted by Rhizopus oryzae MTCC 1987 and its role in retting of Crotalaria juncea fibre

An acidic polygalacturonase (PG) secreted by Rhizopus oryzae MTCC-1987 in submerged fermentation condition has been purified to electrophoretic homogeneity using ammonium sulphate fractionation and anion exchange chromatography on diethylaminoethyl cellulose. The purified enzyme gave a single protein band in sodium dodecyl sulphatepolyacrylamide gel electrophoresis analysis with a molecular mass corresponding to 75.5 kDa. The K m and k cat values of the PG were 2.7 mg/mL and 2.23 × 103 s−1, respectively, using citrus polygalacturonic acid as the substrate. The optimum pH of the purified PG was 5.0 and it does not loose activity appreciably if left for 24 hours in the pH range from 5.0 to 12.0. The optimum temperature of purified enzyme was 50°C and the enzyme does not loose activity below 30°C if exposed for two hours. The purified enzyme showed complete inhibition with 1 mM Ag+, Hg2+ and KMnO4, while it was stimulated to some extent by Co2+. The purified PG exhibited retting of Crotalaria juncea fibre in absence of ethylenediaminetetraacetic acid.