scholarly journals CHARACTERIZATION OF PARTIALLY PURIFIED TYROSINASE ISOLATED FROM BITTER KOLA (GARCINIA KOLA)

2022 ◽  
Author(s):  
B.O. Itakorode ◽  
O.E. Agboola ◽  
M.B. Adeboye ◽  
C.C. Benedict ◽  
K.N. Terkula ◽  
...  
Keyword(s):  
Enzyme Activity ◽  
Peer Review ◽  
Specific Activity ◽  
Ph Value ◽  
Inhibitory Effect ◽  
Enzymatic Browning ◽  
Partial Purification ◽  
Garcinia Kola ◽  
North East ◽  
Review Reports

Objective: Tyrosinase is a glycosylated, copper-containing oxidase that catalyzes the first two steps of mammalian melanogenesis as well as enzymatic browning events in damaged fruits during post-harvest handling and processing. Human skin hyperpigmentation and enzymatic browning in fruits are both undesirable. In this study, the properties and inhibitory effect of some compounds on bitter kola tyrosinase were investigated. Methods: Bitter kola tyrosinase was isolated and characterized using standard protocols. Partial purification was carried out on Sephadex G-100 loaded column chromatography.  Results: Bitter kola tyrosinase was purified with a specific activity of 3.5 U/mg protein, purification fold of 2.4 and a yield of 34%. The optimum pH value was found to be 6.0 while the optimum temperature value for maximum enzyme activity was observed at 60°C. The enzyme was stable at 40oC for 20 minutes. Metals such as NaCl, KCl, MgCl2 and CaCl2 had inhibitory effect on the activity; though MgCl2 and CaCl2 had minimal effect. Also, EDTA, β-marcaptoethanol and glutathione greatly inhibited the enzyme activity at all the tested concentration. Conclusion: The properties of bitter kola tyrosinase compare very well with the tyrosinase from other sources. Also, the study was able to establish the inhibitory effect of some compounds and this could be applied in food processing industries.                  Peer Review History: Received: 2 November 2021; Revised: 11 December; Accepted: 25 December, Available online: 15 January 2022 Academic Editor:  Dr. A.A. Mgbahurike, University of Port Harcourt, Nigeria, [email protected] UJPR follows the most transparent and toughest ‘Advanced OPEN peer review’ system. The identity of the authors and, reviewers will be known to each other. This transparent process will help to eradicate any possible malicious/purposeful interference by any person (publishing staff, reviewer, editor, author, etc) during peer review. As a result of this unique system, all reviewers will get their due recognition and respect, once their names are published in the papers. We expect that, by publishing peer review reports with published papers, will be helpful to many authors for drafting their article according to the specifications. Auhors will remove any error of their article and they will improve their article(s) according to the previous reports displayed with published article(s). The main purpose of it is ‘to improve the quality of a candidate manuscript’. Our reviewers check the ‘strength and weakness of a manuscript honestly’. There will increase in the perfection, and transparency.  Received file:                Reviewer's Comments: Average Peer review marks at initial stage: 6.0/10 Average Peer review marks at publication stage: 7.5/10 Reviewers: Dr. Nazim Hussain, North East Frontier Technical University, Arunachal pradesh, India, [email protected] Ahmad Najib, Universitas Muslim Indonesia, Makassar, Indonesia, [email protected] Prof. Dr. Ali Gamal Ahmed Al-kaf, Sana'a university, Yemen, [email protected] Similar Articles: PHYTOCHEMICAL PURIFICATION OF ACTIVE CONSTITUENTS ISOLATED FROM ROOT OF THE MEDICINAL HERB, CARALLUMA QUADRANGULA

UDP-Glucose: Flavonol 7-O-glucosyltransferase Activity in Flower Extracts of Chrysanthemum segetum

1997 ◽  
Vol 52 (3-4) ◽  
pp. 153-158 ◽  
Author(s):  
K. Stich ◽  
H. Halbwirth ◽  
F. Wurst ◽  
G. Forkmann
Keyword(s):  
Enzyme Activity ◽  
Specific Activity ◽  
Temperature Stability ◽  
Inhibitory Effect ◽  
Hydroxyl Group ◽  
Ph Optimum ◽  
Yellow Colour ◽  
Commercial Strain ◽  
Strong Inhibitory Effect ◽  
Chrysanthemum Segetum

Abstract The yellow colour of Chrysanthemum segetum petals is due to the presence of the 7-O-glucosides of quercetin and particularly gossypetin (8-hydroxyquercetin). In petal extracts of C. segetum an enzyme was demonstrated which catalyzes the transfer of the glucosyl moiety of uridine 5'-diphosphoglucose (UDPG) to the 7-hydroxyl group of flavonols with gossypetin and quercetin as the best substrates. Besides flavonols flavanones and flavones were found to be glucosylated in the 7-position. The pH-optimum of the reaction highly depended on the substrate used. With quercetin as substrate, maximal enzyme activity occurred at a pH of 8.25 and a temperature of 25 °C, but 7-O-glucosylation also proceeded at low temperatures. Studies on temperature stability revealed, that there was no influence on the glucosylation reaction up to 40 °C. Higher temperatures led to a loss of enzyme activity. Using gossypetin as a substrate a similar course of temperature stability was observed. Addition of Mg2+, Ca2+ and KCN slightly stimulated 7-O-glucosylation, whereas Co2+, Cu2+, Fe2+, Hg2+, p-hydroxymercuribenzoate and N-ethylmaleimide showed a strong inhibitory effect. Additional enzymatic studies were performed with the commercial strain " Stern des Orients" where gossypetin 7-O-glucoside is restricted to the inner parts of the petals. For enzyme extracts from both parts of the petals gossypetin was found to be the most attractive substrate. In comparison to quercetin (133.4 μkat / kg protein) an about three times higher specific activity of the 7-O-glucosyltransferase(s) was determined with gossypetin (382.1 μkat/ kg protein) as substrate, indicating that hydroxylation of quercetin in 8-position to gossypetin precedes 7-O-glucosylation.

A β-Mannanase from Bacillus subtilis B36: Purification, Properties, Sequencing, Gene Cloning and Expression in Escherichia coli

2006 ◽  
Vol 61 (11-12) ◽  
pp. 840-846 ◽  
Author(s):  
Ya Nan Li ◽  
Kun Meng ◽  
Ya Ru Wang ◽  
Bin Yao
Keyword(s):  
Escherichia Coli ◽  
Enzyme Activity ◽  
Bacillus Subtilis ◽  
Specific Activity ◽  
Ph Value ◽  
High Specificity ◽  
Apparent Molecular Weight ◽  
Cloning And Expression ◽  
Gene Cloning And Expression ◽  
Reading Frame

Abstract MANB36, a secrete endo-β-1,4-D-mannanase produced by Bacillus subtilis B36, was puri­fied to homogeneity from a culture supernatant and characterized. The optimum pH value for the mannanase activity of MANB36 is 6.4 and the optimum temperature is 50 °C. The enzyme activity of MANB36 is remarkably thermostable at 60 °C and the specific activity of MANB36 is 927.84 U/mg. Metal cations (except Hg2+ and Ag+), EDTA and 2-mercaptoetha- nol (2-ME) have no effects on enzyme activity. This enzyme exhibits high specificity with the substituted galactomannan locust bean gum (LBG). The gene encoding for MANB36, manB36, was cloned by PCR and sequenced. manB36 contains a single open reading frame (ORF) consisting of 1104 bp that encodes a protein of 367 amino acids. The predicted mo­lecular weight of 38.13 kDa, calculated by the deduced protein of the gene manB36 without signal peptide, coincides with the apparent molecular weight of 38.0 kDa of the purified MANB36 estimated by SDS-PAGE. The mature protein of MANB36 has been expressed in Escherichia coli BL21 and the expressed mannanase has normal bioactivity.

scholarly journals Isolation of Xylanase Producing Strains, Optimization of Fermentation Conditions and Research on Enzymatic Properties

2021 ◽  
Vol 12 (2) ◽  
pp. 1
Author(s):  
Ji Huilong ◽  
Gao Xin ◽  
WU Wenxuan ◽  
Ma Zhuang ◽  
Qing Qing
Keyword(s):  
Enzyme Activity ◽  
Specific Activity ◽  
Ph Value ◽  
Fermentation Broth ◽  
Sodium Dodecyl ◽  
Alkali Resistance ◽  
Initial Ph ◽  
Acid And Alkali Resistance ◽  
Optimal Reaction Temperature ◽  
Optimization Of Fermentation

In this study, we successfully isolated a strain of Aspergillus oryzae TR08, which produced xylanase secreted to the outside of the cell productively. The enzyme activity and specific activity in the fermentation broth of this strain reached peak values of 451 IU/mL and 1963 IU/mg after 156 h of fermentation. A single factor experiment was designed, and it was found that the strain was adjusted to the initial pH of the fermentation broth to 7.5 in a shaker at 180 rpm and 32 °C. After 156 h of fermentation, the enzyme activity reached a maximum of 1264 IU/mL. The optimal reaction temperature and pH value of the xylanase were 55 °C and 7.5, respectively, and it had excellent acid and alkali resistance and a wide pH activity range. The xylanase was increased the catalytic activity by 15% in 0.25 mM Fe3+, and the biological activity of the enzyme was not affected in the sodium dodecyl sulfate environment.

A simple procedure for partial purification of an RNAase of Entamoeba invadens

1981 ◽  
Vol 27 (8) ◽  
pp. 856-859
Author(s):  
David L. Weller ◽  
Andrea Richman
Keyword(s):  
Enzyme Activity ◽  
Isoelectric Focusing ◽  
Sucrose Gradient ◽  
Specific Activity ◽  
Simple Procedure ◽  
Partial Purification ◽  
Step Procedure ◽  
Entamoeba Invadens

The behavior of an RNAase, present in centrifugally clarified homogenates of axenic trophozoites of Entamoeba invadens, on isoelectric focusing (IEF) and agarose–poly(G) chromatography is described. The results led to a simple two-step procedure for partial purification of the RNAase in which fractionation of the homogenate by IEF is followed by agarose–poly(G) chromatography. Recovery of enzyme activity has ranged from 50 to 80% of that present in homogenates, and increases of 80- to 160-fold in the specific activity have been obtained using the procedure. A single zone of activity was observed on analysis of the partially purified RNAase by sucrose gradient IEF and velocity zonal ultracentrifugation.

scholarly journals Partial purification of (Ca2+ + Mg2+)-dependent ATPase from pig smooth muscle and reconstitution of an ATP-dependent Ca2+-transport system

1981 ◽  
Vol 198 (2) ◽  
pp. 265-271 ◽  
Author(s):  
F Wuytack ◽  
G De Schutter ◽  
R Casteels
Keyword(s):  
Enzyme Activity ◽  
Smooth Muscle ◽  
Transport System ◽  
Microsomal Fraction ◽  
Specific Activity ◽  
Partial Purification ◽  
Total Enzyme Activity ◽  
Dependent Atpase ◽  
Specific Activities ◽  
Total Enzyme

(CaMg)ATPase [(Ca2+ + Mg2+)-dependent ATPase] was partially purified from a microsomal fraction of the smooth muscle of the pig stomach (antrum). Membranes were solubilized with deoxycholate, followed by removal of the detergent by dialysis. The purified (CaMg)ATPase has a specific activity (at 37 degrees C) of 157 +/- 12.1 (7)nmol.min-1.mg-1 of protein, and it is stimulated by calmodulin to 255 +/- 20.9 (7)nmol.min.mg-1. This purification of the (CaMg)ATPase resulted in an increase of the specific activity by approx. 18-fold and in a recovery of the total enzyme activity of 55% compared with the microsomal fraction. The partially purified (CaMg)ATPase still contains some Mg2+-and (Na+ + K+)-dependent ATPase activities, but their specific activities are increased relatively less than that of the (CaMg)ATPase. The ratios of the (CaMg)ATPase to Mg2+- and (Na+ + K+)-dependent ATPase activities increase from respectively 0.14 and 0.81 in the crude microsomal fraction to 1.39 and 9.07 in the purified preparation. During removal of the deoxycholate by dialysis, vesicles were reconstituted which were capable of ATP-dependent Ca2+ transport.

scholarly journals Partial Purification, Characterization, and Application of Extracellular Aspartic Protease from Lactobacillus casei WSP in Producing the Bioactive Peptides with Antibacterial and Antioxidant Activity

2018 ◽  
Vol 22 (2) ◽  
pp. 47
Author(s):  
Akhmad Solikhin ◽  
Apon Zaenal Mustopa ◽  
Suharsono Suharsono ◽  
Wendry Setiyadi Putranto
Keyword(s):  
Enzyme Activity ◽  
Metal Ion ◽  
Lactobacillus Casei ◽  
Specific Activity ◽  
Gel Filtration ◽  
Fold Increase ◽  
Iodoacetic Acid ◽  
Aspartic Protease ◽  
Partial Purification ◽  
Antioxidant Agents

   Lactobacillus casei WSP-derived an aspartic protease was sequentially purified by using chromatography gel filtration sephadex G-50. It resulted in a 22.81-fold increase of specific activity (51.5 U/mg) with a final yield of 1.9%. The estimated molecular weight of the purified enzyme was 37 kDa and showed gelatinolytic activity in zymogram assay. The enzyme exhibited optimum activity at 40ºC and pH 6 with casein as the substrate. Enzyme activity was significantly inhibited by pepstatin A (0.5 mM and 1 mM), confirming that this enzyme is a group of aspartic proteases, while other inhibitors such as EDTA, PMSF and iodoacetic acid showed no inhibition effect on the activity of enzyme. The addition of metal ion to the enzyme decreased enzyme activity, indicating the proteolytic enzyme was metal ion- dependent. Denaturant such as DDT tended to increase caseinolytic activity. Furthermore, this enzyme was capable of generating the new peptides from skimmed milk with the size 8 kDa, 10 kDa and 15 kDa. These peptides have potential as antibacterial and antioxidant agents.

scholarly journals THE EFFECT OF NANOSILVER AND CHLORHEXIDINE MOUTHWASH ON ANAEROBIC PERIODONTAL PATHOGENS COUNTS

2019 ◽  
Author(s):  
Amani Abdulhakeem Al-Sharani ◽  
Waddah Al-Hajj ◽  
Hassan A. Al-Shamahy ◽  
Bushra Mohammed Jaadan
Keyword(s):  
Peer Review ◽  
Inhibitory Effect ◽  
Periodontal Pathogens ◽  
Microbial Counts ◽  
Gingival Health ◽  
Group I ◽  
Significant Difference ◽  
Review Reports ◽  
Mouth Wash ◽  
E Mail

The necessitate for frequent application of Chlorhexidine (CHX), and other side effects has encouraged the search for option that are more suitable for patients as nanosilver mouthwash (NS). So the aim of this study was to determine the effects of a mouthwash made with nanosilver on dental plaque microbial counts and compare it with commercially available Chlorhexidine.   Sixty-two plaque-induced gingivitis patients were allocated into two groups and asked to rinse with 10 ml of NS and CHX, immediately after brushing, for 1 min, in the morning and evening. Sub gingival plaque microbial counts were taken at baseline, two weeks, and finally at four weeks for each patient. Subsequently, the samples were collected, transferred and cultured in blood agar in anaerobic media. The colonies were counted and expressed as CFUs. The statistical analysis between CFUs variables within groups was calculated and the variation significance was calculated by performed t-test.  It is very obvious that the values of CFU decreased significantly (p<0.001) as the time of use nanosilver until reaching the highest value when the time of use was 4 weeks [70.3±47 to 32.4±24.6 (2 weeks), and 14.2±9.9 (4 weeks) with inhibition of growth rate after 2 weeks was 46% and after 4 weeks was 79.7%. The effect of commercially available CHX mouthwash was approximately similar to the effect of  NS mouthwash used. In conclusion, both Group I and Group II showed similar effect on inhibition anaerobic periodontal pathogens counts and gingival health. There was significant inhibitory effect on microbial counts where NS mouth-wash had shown better results than CHX, but there was no significant difference between the nanosilver mouth wash and the Chlorhexidine mouthwash. Peer Review History: UJPR follows the most transparent and toughest ‘Advanced OPEN peer review’ system. The identity of the authors and, reviewers will be known to each other. This transparent process will help to eradicate any possible malicious/purposeful interference by any person (publishing staff, reviewer, editor, author, etc) during peer review. As a result of this unique system, all reviewers will get their due recognition and respect, once their names are published in the papers. We expect that, by publishing peer review reports with published papers, will be helpful to many authors for drafting their article according to the specifications. Auhors will remove any error of their article and they will improve their article(s) according to the previous reports displayed with published article(s). The main purpose of it is ‘to improve the quality of a candidate manuscript’. Our reviewers check the ‘strength and weakness of a manuscript honestly’. There will increase in the perfection, and transparency. Received file Average Peer review marks at initial stage: 5.5/10 Average Peer review marks at publication stage: 8.0/10 Reviewer(s) detail: Name: Dr. Mohamed Salama Affiliation: Modern University for Technology & Information, Egypt E-mail: [email protected]   Name: Dr. Tamer Elhabibi Affiliation: Suez Canal University, Egypt E-mail: [email protected] Comments of reviewer(s):

Pengaruh Penambahan Molases Pada Kulit Pisang Kapendis Untuk Media Produksi Xilanase B.Stearothermophillus DSM 22

2019 ◽  
Vol 15 (3) ◽  
Author(s):  
Trismillah
Keyword(s):  
Enzyme Activity ◽  
Ammonium Sulfate ◽  
Banana Peel ◽  
Partial Purification ◽  
Temperature Conditions ◽  
Cavendish Banana ◽  
Working Volume ◽  
Initial Ph ◽  
Xylanase Enzyme

Cavendish banana peel can be used as a substitute for the expensive xylan, while molasses than as a source of carbon as well as nitrogen, minerals and nutrients needed for the growth of microbes that can produce the enzyme. Xylanase produced from Bacillus stearothermopillus DSM 22, using media cavendish banana peels with the addition of molasses 1%, 2%, and 3%. Fermentation is done in a shaker incubator at 550C temperature conditions, initial pH 8, and 250 rpm agitation. The result showed the highest enzyme activity of 4,14 ± 0,16 U/mL min., on the addition 2% molasses after 24 hours. Further fermentation carried out in the fermenter working volume of 3.5 liters, with the condition of temperature 550C, pH 8, aeration 1 vvm, agitation 250 rpm, the highest spesific enzyme of activity of 51,62 ± 0,16 U/mg after 24 hours. Partial purification of xylanase enzyme fermentation is done with the results of microfiltration, ultrafiltration, ammonium sulfate (0-80%) and dialysis. There is an increase in the purity of the enzyme at each stage of purification, the highest purity on dialysis 3.23 times of crude enzymes.Kulit buah pisang kapendis dapat digunakan sebagai pengganti xilan yang harganya mahal, sementara molases selain sebagai sumber karbon serta nitrogen, mineral dan nutrisi dibutuhkan untuk pertumbuhan mikroba yang dapat menghasilkan enzim. Xilanase yang dihasilkan dari Bacillus stearothermopillus DSM 22, menggunakan media kulit pisang kapendis dengan penambahan molase 1%, 2%, dan 3%. Fermentasi dilakukan dalam shaker inkubator pada temperatur 550C, pH awal 8, dan agitasi 250 rpm. Hasilnya menunjukkan aktivitas enzim tertinggi 4,14 ± 0,16 U/mL min., pada penambahan 2% molases setelah 24 jam. Selanjutnya fermentasi dilakukan di dalam fermentor, volume kerja dari 3,5 liter, dengan kondisi temperatur 550C, pH 8, aeration 1 vvm, agitasi 250 rpm, aktivitas spesifik tertinggi 51,62 ± 0,16 U/mg setelah 24 jam. Pemurnian parsial fermentasi enzim xilanase dilakukan dengan hasil mikrofiltrasi, ultrafiltrasi, amonium sulfat (0-80%) dan dialisis. Ada peningkatan kemurnian enzim pada setiap tahap pemurnian, kemurnian tertinggi pada dialisis 3,23 kali dari enzim kasar.Keywords: Xylanase, B. stearothermophillus DSM 22, Cavendish banana peel, molasses, enzyme activity

scholarly journals Partial purification and biochemical characterization of a new highly acidic NYSO laccase from Alcaligenes faecalis

2020 ◽  
Vol 18 (1) ◽  
Author(s):  
Soad A. Abdelgalil ◽  
Ahmad R. Attia ◽  
Reyed M. Reyed ◽  
Nadia A. Soliman
Keyword(s):  
Enzyme Activity ◽  
Sodium Dodecyl ◽  
Alcaligenes Faecalis ◽  
Maximum Activity ◽  
Sodium Oxalate ◽  
Partial Purification ◽  
Bromophenol Blue ◽  
Bromocresol Purple ◽  
Laccase Enzyme

Abstract Background Due to the multitude industrial applications of ligninolytic enzymes, their demands are increasing. Partial purification and intensive characterization of contemporary highly acidic laccase enzyme produced by an Egyptian local isolate designated Alcaligenes faecalis NYSO were studied in the present investigation. Results Alcaligenes faecalis NYSO laccase has been partially purified and intensively biochemically characterized. It was noticed that 40–60% ammonium sulfate saturation showed maximum activity. A protein band with an apparent molecular mass of ~ 50 kDa related to NYSO laccase was identified through SDS-PAGE and zymography. The partially purified enzyme exhibited maximum activity at 55 °C and pH suboptimal (2.5–5.0). Remarkable activation for enzyme activity was recognized after 10-min exposure to temperatures (T) 50, 60, and 70 °C; time elongation caused inactivation, where ~ 50% of activity was lost after a 7-h exposure to 60 °C. Some metal ions Cu2+, Zn2+, Co2+, Ni2+, Mn2+, Cd2+, Cr2+, and Mg2+ caused strong stimulation for enzyme activity, but Fe2+ and Hg2+ reduced the activity. One millimolar of chelating agents [ethylenediamine tetraacetic acid (EDTA), sodium citrate, and sodium oxalate] caused strong activation for enzyme activity. Sodium dodecyl sulfate (SDS), cysteine-HCl, dithiothreitol (DTT), β-mercaptoethanol, thioglycolic acid, and sodium azide caused strong inhibition for NYSO laccase activity even at low concentration. One millimolar of urea, imidazole, kojic acid, phenylmethylsulfonyl fluoride (PMSF), H2O2, and Triton X-100 caused activation. The partially purified NYSO laccase had decolorization activity towards different dyes such as congo red, crystal violet, methylene blue, fast green, basic fuchsin, bromophenol blue, malachite green, bromocresol purple eriochrome black T, and Coomassie Brilliant Blue R-250 with various degree of degradation. Also, it had a vast range of substrate specificity including lignin, but with high affinity towards p-anisidine. Conclusion The promising properties of the newly studied laccase enzyme from Alcaligenes faecalis NYSO strain would support several industries such as textile, food, and paper and open the possibility for commercial use in water treatment. It will also open the door to new applications due to its ligninolytic properties in the near future.

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