scholarly journals Studies on the production of glucose isomerase by Bacillus licheniformis

2015 ◽  
Vol 17 (3) ◽  
pp. 84-88 ◽  
Author(s):  
Ogbonnaya Nwokoro

Abstract This work reports the effects of some culture conditions on the production of glucose isomerase by Bacillus licheniformis. The bacterium was selected based on the release of 3.62 mg/mL fructose from the fermentation of glucose. Enzyme was produced using a variety of carbon substrates but the highest enzyme activity was detected in a medium containing 0.5% xylose and 1% glycerol (specific activity = 6.88 U/mg protein). Media containing only xylose or glucose gave lower enzyme productivies (specific activities= 4.60 and 2.35 U/mg protein respectively). The effects of nitrogen substrates on glucose isomerase production showed that yeast extract supported maximum enzyme activity (specific activity = 5.24 U/mg protein). Lowest enzyme activity was observed with sodium trioxonitrate (specific activity = 2.44 U/mg protein). In general, organic nitrogen substrates supported higher enzyme productivity than inorganic nitrogen substrates. Best enzyme activity was observed in the presence of Mg2+ (specific activity = 6.85 U/mg protein) while Hg2+ was inhibitory (specific activity = 1.02 U/mg protein). The optimum pH for best enzyme activity was 6.0 while optimum temperature for enzyme production was 50ºC.

1970 ◽  
Vol 1 ◽  
pp. 6-10 ◽  
Author(s):  
Bidur Dhungel ◽  
Manoj Subedi ◽  
Kiran Babu Tiwari ◽  
Upendra Thapa Shrestha ◽  
Subarna Pokhrel ◽  
...  

Glucose isomerase (EC 5.3.1.5) was extracted from Streptomyces spp., isolated from Mt. Everest soil sample, and purified by ammonium sulfate fractionation and Sepharose-4B chromatography. A 7.1 fold increase in specific activity of the purified enzyme over crude was observed. Using glucose as substrate, the Michaelis constant (KM<) and maximal velocity (Vmax) were found to be 0.45M and 0.18U/mg. respectively. The optimum substrate (glucose) concentration, optimum enzyme concentration, optimum pH, optimum temperature, and optimum reaction time were 0.6M, 62.14μg/100μl, 6.9, 70ºC, and 30 minutes, respectively. Optimum concentrations of Mg2+ and Co2+ were 5mM and 0.5mM, respectively. The enzyme was thermostable with half-life 30 minutes at 100ºC.DOI: 10.3126/ijls.v1i0.2300 Int J Life Sci 1 : 6-10


2021 ◽  
Vol 66 (1) ◽  
pp. 72-79
Author(s):  
Thuoc Doan Van ◽  
Hung Nguyen Phuc

The effect of physical parameters such as temperature and pH on the production, activity, and stability of α-amylase from Bacillus subtilis V37 was investigated. The results indicated that the optimum culture conditions for enzyme activity were pH 7.0 and 35 oC. The optimum pH and temperature for enzyme activity were 6.0 and 70 oC. The crude enzyme was found to be stable in the pH range of 5.0 to 7.0. The enzyme was stable for 1 h at a temperature from 30 to 80 oC; nearly 100% of enzyme activity remained at temperatures of 30 - 40 oC, and about 34% of original activity remained at a temperature of 80 oC. These features demonstrated that α-amylase from B. subtilis V37 can be applied in many areas such as the food, fermentation, and animal feed industries.


Author(s):  
Emi Latifah ◽  
Putri Dwi Mulyani ◽  
Yekti Asih Purwestri

Bacteria BSR 2, Pseudomonas alcaligenes (BSR 3), Brevibacillus parabrevis (BSR 8), Brevibacillus sp. (BSR 9), isolated from termite gut and Bacillus licheniformis (BSA B1) isolated from milkfish gut have been known to possess celluloytic activity. However, their lignolytic ability has not been known. This study aimed to determine the lignolytic ability of bacteria isolated from termit (Coptotermes sp.) and milkfish (Chanos chanos Forsskal, 1775) guts and their enzymes characterization. The qualitative test was done through the spot test method, while quantitative assay was performed spectrophotometrically at 335 nm to calculate vanillin concentration. The isolates were grown in Lignin Mineral Medium, then the optical density (OD620) were measured every 24 hours for 5 days using spectrophotometer to determine their growth profile and the best isolation time of the lignolytic enzyme. Based on results, the best lignolytic enzyme isolation time for strains Bacillus licheniformis (BSA B1) and BSR 2 were 5 days, yielding lignolytic enzyme activity of 0.961 ± 0.168 U/mg and 2.176 ± 0.088 U/mg respectively,  while strains Pseudomonas alcaligenes (BSR 3), Brevibacillus parabrevis (BSR 8), and Brevibacillus sp. (BSR 9) were 4 days, yielding of 1.206 ± 0.045 U/mg, 1.162 ± 0.191 U/mg, and 0.896 ± 0.108 U/mg, respectively. The strain BSR 2 showed the highest lignolytic activity compared to other strains. The optimum temperature for lignolytic enzyme activity of BSR 2 was 30 ℃ and the optimum pH was 7. The lignolytic enzyme activity showed that these bacterial isolates can be a chance to be used as new alternative lignolytic enzyme source in commercial bioconversion process.


2013 ◽  
Vol 760 ◽  
pp. 73-78
Author(s):  
Anima Nanda ◽  
T. Sudhakar ◽  
B.K. Nayak ◽  
J. Prem Kumar

S: - Among the six isolated amylase producing strains,Bacillus licheniformis(B1), the thermostable strain was selected from the soil of a paddy field. Its enzyme productivity and activity were evaluated. The activity of enzyme was calculated as 27.77 IU/ml. Effects of various carbon and organic nitrogen sources, and C/N ratio on enzyme production were examined. Maximum α - amylase production was obtained in medium containing 1% starch. Fructose supported the maximum amylase production among all the sugar studied. Of the organic nitrogen sources tested, peptone was found to be the best organic nitrogen source for excess yield of the enzyme. The optimum C/N ratio was found to be 1:1. The α amylase exhibited activity at a wide pH and temperature range and activity were found to be optimal at pH 6 and 40 °C respectively. The molecular weight of α amylase was calculated by sodium dodecyl sulphate gel electrophoresis and found to be around 29,000 Daltons.


2013 ◽  
Vol 2013 ◽  
pp. 1-8 ◽  
Author(s):  
A. S. Chauhan ◽  
N. Srivastava ◽  
H. K. Kehri ◽  
B. Sharma

Microbial α-galactosidase preparations have implications in medicine and in the modification of various agricultural products as well. In this paper, four isolated fungal strains such as AL-3, WF-3, WP-4 and CL-4 from rhizospheric soil identified as Penicillium glabrum (AL-3), Trichoderma evansii (WF-3), Lasiodiplodia theobromae (WP-4) and Penicillium flavus (CL-4) based on their morphology and microscopic examinations, are screened for their potential towards α-galactosidases production. The culture conditions have been optimized and supplemented with specific carbon substrates (1%, w/v) by using galactose-containing polysaccharides like guar gum (GG), soya casein (SC) and wheat straw (WS). All strains significantly released galactose from GG, showing maximum production of enzyme at 7th day of incubation in rotary shaker (120 rpm) that is 190.3, 174.5, 93.9 and 28.8 U/mL, respectively, followed by SC and WS. The enzyme activity was stable up to 7days at −20°C, then after it declines. This investigation reveals that AL-3 show optimum enzyme activity in guar gum media, whereas WF-3 exhibited greater enzyme stability. Results indicated that the secretion of proteins, enzyme and the stability of enzyme activity varied not only from one strain to another but also differed in their preferences of utilization of different substrates.


2020 ◽  
Vol 28 (S2) ◽  
Author(s):  
Marwan Jawad Msarah ◽  
Ayesha Firdose ◽  
Izyanti Ibrahim ◽  
Wan Syaidatul Aqma

Screening of new source of novel and industrially useful enzymes is a key research pursuit in enzyme biotechnology. The study aims to report the characteristics of novel thermophilic microorganisms isolated from Sungai Klah (SK) Hot Spring, Perak, Malaysia, that can produce α-amylase. The morphological and biochemical properties were examined for SUNGC2 sample. The isolate was further screened for amylase, followed by 16S rRNA and analytical profile index (API) test. This isolate was further subjected to pH optimisation for α-amylase production. It was found that SUNGC2 was an α-amylase producer and was identified as Bacillus licheniformis SUNGC2 with NCBI accession numbers MH062901. The enzyme was found to exhibit an optimum temperature of 50°C and a pH of 7.0. The relative activity of the enzyme was obtained based on the improvement of the culture conditions. The highest amount of amylase production was 24.65 U/mL at pH 7.0, consecutively the growth was also highest at pH 7.0 with a 9.45-fold increase in specific activity by ammonium phosphate precipitation of 80% (w/v). The results showed that the bacteria isolated from the hot spring are a significant source of thermophilic enzymes that are highly promising in biotechnology.


2019 ◽  
Vol 64 (4) ◽  
pp. 539-547
Author(s):  
Mohammed Inuwa Ja’afaru ◽  
Konjerimam Ishaku Chimbekujwo ◽  
Obinna Markraphael Ajunwa

Proteases are important industrial enzymes and fungi prove to be good sources of such enzymes. Purification techniques are however necessary for increased specificity in activity and better industrial value. Based on this, a protease produced by a Fusarium oxysporum was purified to homogeneity by Sephadex G-200 column and α–casein agarose chromatography. The enzyme had a molecular weight of 70 kDa in SDS-PAGE. Purified Fusarium oxysporum protease had a specific activity of 93.88 U/mg protein. The purification magnitude was 7.7 and the total yield was 20 %. Purified protease had an optimum pH of 5.0 while the optimum temperature was 40 °C. The enzyme was also thermotolerant (approximately 100 % at 40 °C for 2 h). The enzyme activity was stimulated by surfactants and metal ions like, Tween-20 and Mg2+. Enzyme activity was inhibited in presence of PMSF and EDTA. Casein was found to be the best substrate for protease activity of Fusarium oxysporum FWT1. Protease were tested upon blood stain for de-clotting of blood and was found to exhibit good de-clotting and de-staining activity after 15 minutes treatment time.


1979 ◽  
Vol 57 (6) ◽  
pp. 573-577 ◽  
Author(s):  
Daniel A. K. Roncari ◽  
Esther Y. W. Mack ◽  
Dominic K. Yip

The availability of a propagating adipocyte precursor culture system has provided the opportunity to study biochemical processes under conditions in which any known interacting influences are controlled. We have studied the activity of various triacylglycerol-biosynthetic enzymes during maturation of rat epididymal adipocyte precursors and any possible effect of insulin on enzyme activity. At certain times in culture, the specific activity of microsomal phosphatidate phosphohydrolase (EC 3.1.3.4) and diacylglycerol acyltransferase (EC 2.3.1.20) is significantly enhanced in cells grown in the presence of added insulin. Under the culture conditions used in this study, the adipocyte precursors acquire several small lipid inclusions and become rounder, but do not assume the signet-ring appearance of mature fat cells during the first 2 weeks of monolayer confluence. Consequently, the effects of the hormone on enzyme activity become evident prior to complete morphological maturation. Phosphatidate phosphohydrolase is believed to be a rate-controlling enzyme in triacylglycerol synthesis in adipose tissue and liver. The fact that the adipocyte precursor microsomal, rather than cytosolic, phosphohydrolase is influenced by insulin suggests that the membrane-bound enzyme is the regulatory phosphohydrolase in intact cells. The enhancement of diacylglycerol acyltransferase activity may be of significance in the reesterification of fatty acids with diacylglycerols, a reaction that by passes the phosphohydrolase step. Thus, in addition to the well-known mechanisms by which insulin promotes triacylglycerol accretion in adipocytes and their precursors, the hormone significantly enhances the specific activity of critical enzymes of triacylglycerol synthesis.


Biologia ◽  
2015 ◽  
Vol 70 (12) ◽  
Author(s):  
Essam Kotb ◽  
Gamal El-Deen A. Helal ◽  
Faten M. Edries

AbstractA potential screening programme for fibrinolytic filamentous fungi in the Egyptian environment was done for the first time. The proteolytic activity was positive in 38.5% of isolates, whilst only thirty-four of them were able to produce fibrinolytic enzymes. The two most potent isolates were identified as Aspergillus brasiliensis AUMC 9735 and Aspergillus flavus AUMC 9736. Under submerged culture conditions, the two strains were able to excrete fibrinolytic enzymes, reaching a maximum at 5 and 9 days, respectively. Maximal enzyme productivity by both strains was achieved by lactose and sucrose, respectively. All tested nitrogen sources were stimulatory for enzyme production by both strains, except for ammonium acetate in the case of A. brasiliensis AUMC 9735. Purification of A. brasiliensis AUMC 9735 enzyme increased its specific activity to 83.5-fold with a recovery of 9.1% and molecular weight of 40 kDa. Maximal activity was recorded at pH 8 (stability at pH 6-11). The purified enzyme showed higher thermostability than most fibrinolytic enzymes of filamentous fungi with the midpoint temperature (T


2018 ◽  
Vol 5 (3) ◽  
pp. 135-141 ◽  
Author(s):  
. Shreya ◽  
Arun Kumar Sharma ◽  
Vinay Sharma ◽  
Jyoti Saxena

The present study aimed to optimize culture conditions for optimal growth and production of extracellular lipase. Lipolytic fungal strain named as S3St2 previously isolated from a petrol pump soil sample of Newai Town was used for optimization study. Among the tested carbohydrate carbon sources, polysaccharide-starch exhibited maximum lipase production (21.25±0.70 IU/ml/min) with highest specific activity (1.47±0.06 U/mg). Lipase activity and specific activity were higher with mustard oil 1 % (v/v) among all lipidic carbon sources. Among inorganic nitrogen source, potassium nitrate was found best inducer of lipase activity, malt extract supported the fungus growth (dry weight of cell pellets was 0.467 g) and exhibited maximum lipase activity among all organic nitrogen sources. Lipase activity was optimum at pH 8.0, indicates alkalophillic nature of production media supports the growth of fungus. Higher lipase activity (27.92±0.87 IU/ml/min) was detected at 28ºC. The incubation time of 5 days was found optimum for maximum lipase production (31.51±0.21 IU/ml/min).


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