Effect of temperature and pH on the production, activity, and stability of α-amylase from Bacillus subtilis V37

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.

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.


2021 ◽  
Vol 16 (7) ◽  
pp. 84-91
Author(s):  
Maslinda Alias ◽  
Hakim Che Harun Mohammad ◽  
Ashraf Razali Nurul ◽  
Jasnizat Saidin ◽  
Nazaitulshila Rasit ◽  
...  

This research aims to produce thermostable alkaline protease from Bacillus subtilis isolated from La Hot Spring, Terengganu, Malaysia. The study was also conducted to determine the optimum conditions for protease production and stability by considering several parameters including pH, temperature and salt concentration. All seven bacteria were screened on skim milk agar overnight at 37 °C. Three strains with the highest proteolytic activity were identified in protease specific medium. The thermostable alkaline protease had an optimum temperature of 60 °C which achieved 85.73, 82.90 and 83.05 U/mL of protease activity for the three strains respectively. Furthermore, the strains exhibited significant activity of more than 90% from their original activity. Meanwhile, the optimum pH for protease production was pH 9 with the protease activity of 76.76, 79.71 and 88.39 U/mL for TB4, TB6 and TB9 strains, respectively. Proteases were found stable at pH 9 where the loss did not exceed 30% of its original activity. Collectively, all of the data emphasised that proteases from B. subtilis were alkaline thermostable proteases in accordance with a recent report. The finding highlights the viability of the proteases for biotechnological and industrial applications.


2010 ◽  
Vol 113-116 ◽  
pp. 226-230 ◽  
Author(s):  
Chun Lei Wang ◽  
Min Zhao ◽  
Xing Dong Wei ◽  
Tai Lun Li ◽  
Lei Lu

Treatment of xenobiotic compounds such as textile dyes with bacterial laccases is limited to the acid pH range and moderate temperatures. A bacterial strain, designated as WD23, was isolated from forest soil using Luria-Bertani medium supplemented with 0.4 mmol/L Cu2+. The isolated strain was identified as Bacillus subtilis by physiological and biochemical tests and 16S rDNA sequence analysis. Here we charactered the spore-bound laccase of B. subtilis WD23 and used the laccase to decolorize dyes. The spores of the strain showed laccase-like activity, oxidizing syringaldazine, 2,6-dimethoxyphenol and 2,2′-azino-bis(3-ethylbenzthiazoline-6-sulfonate acid)(ABTS). The optimum pH and temperature for the spore-bound laccase were 6.8 and 60°C, respectively. It also showed higher stabilities over a broad pH range, the pH half-life was more than 6 months at pH 6.8. The spore laccase could efficiently decolorize 50~90% of anthraquinone and azo dyes in 24 h. The spore laccase can play an important role in bioremediation.


2019 ◽  
Vol 16 (04) ◽  
pp. 817-826
Author(s):  
Endang Rahmawati ◽  
Abinawanto Abinawanto ◽  
Is Helianti

ABSTRACT: Proteases are potential enzymes that utilized in various industrial fields, and the demand of these enzymes is increasing. Bacillus halodurans CM1 is Indonesia indigenous bacterium which is detected to be able to produce alkalotermophilic protease enzyme. In this study, we subcloned the protease gene consist of Open Reading Frame of protease gene and its promoter from Bacillus halodurans CM1 in Bacillus subtilis DB104 via conjugation, and analyzed the expression of the recombinant protease. The protease gene is 1 417 bp length including the open reading frame and the promoter, and obtained by PCR and cloned into pGEM T easy. After confirmed by sequencing, the gene was subcloned into vector pBBRE194, then the recombinant plasmid was transformed into E. coli S17-1. This E.coli was then conjugated to Bacillus subtilis DB104. The target recombinant B. subtilis DB104 has been obtained confirmed by plasmid verification and erythromycin resistance. The recombinant protease produced showed the highest enzyme activity at 50oC and pH 9 (with pH range 5-9) which with protease activity 13.66 U/mL.


2020 ◽  
Vol 2 (02) ◽  
pp. 36 ◽  
Author(s):  
Renna Eliana Warjoto ◽  
Felianti Felianti ◽  
Bibiana Widiyati Lay

Carotenoids are natural pigments with colors ranging from yellow to red that are beneficial for food, cosmetics, and animal feed industries. These pigments can be found in fruits, vegetables, algae, and microorganisms. Among all microorganisms that have been known to produce carotenoids, Rhodosporidium paludigenum is still poorly investigated. Therefore, this study aimed to determine the potential of carotenoid production by R. paludigenum using cassava starch hydrolyzed by Bacillus subtilis as a substrate. The cassava starch for hydrolysis was divided into four concentrations, i.e., 2%, 4%, 6%, and 8% w/v. During the hydrolysis period, the amylase enzyme activity produced by B. subtilis was evaluated. The reducing sugar concentration was then examined to determine the optimum medium for carotenoid production. The highest amylase enzyme activity was produced on the second day in all cassava starch concentrations. However, the highest reducing sugar concentration was discovered in the 6% w/v cassava starch concentration. Thus, a batch submerged fermentation for carotenoid production by R. paludigenum was performed using the hydrolysate as the sole substrate. At the end of the fermentation, the total carotenoid was extracted, and the concentration was determined using spectrophotometry. The total yield of xanthophyll over biomass was higher than that of β-carotene. These findings elucidated the potency of cassava starch hydrolysate obtained from the starch hydrolyzed by B. subtilis, for carotenoid production by the red yeast R. paludigenum.


2018 ◽  
Vol 5 (10) ◽  
pp. 405-416 ◽  
Author(s):  
Isaac Oluseun Adejumo ◽  
Charles Oluwaseun Adetunji

The management of solid wastes has been a major concern to many cities of the world due to daily increasing rural-urban migration and globalization. Due to a greater consumption of poultry meat, the disposal of feather wastes has contributed to the daily increasing environmental pollution. Agricultural wastes (such as poultry feathers) are disposed by burning, which consequently constitute environmental pollution and their chemical or mechanical conversion into animal feed normally leads to minimization of amino acids. The application of biotechnology through the utilisation of enzymes is considered an easy and inexpensive means of producing valuable products from poultry feather wastes. Bacillus subtilis was isolated from a dumping site and the plates were incubated on nutrient agar. The treatments containing 200 mL each of crude enzyme, immobilized enzyme and sterilized water were added to the bioreactor for biodegradation of chicken feathers. After hydrolysis, the feathers were dried and the products labelled microbial biodegraded feather meal. The effect of temperature, keratinolytic activity and the influence of the immobilised and crude enzyme-degraded feather meal on broiler chickens were assessed. The optimal activity and biodegradative potential of the keratinolytic enzyme was observed as 45 oC and 48 h after fermentation, respectively. The weight gain of the birds fed immobilised enzyme-degraded feather meal-based diet compared with the control. The enzyme-degraded feather meal is safe for inclusion in broilers' diet and slight feeding manipulations could improve their performance.


2014 ◽  
Vol 25 ◽  
pp. 29-38 ◽  
Author(s):  
Shahriar Saeidian

Polyphenol oxidase (PPO) from hawthorn was extracted and partially purified through (NH4)2SO4 precipitation, dialysis and ion exchange chromatography. The activity of polyphenol oxidase was investigated in Crataegus spp. Spectrophotometric method was used to assay the enzyme activity and the kinetic constants - maximum enzyme velocity (Vmax) and Michealis - Menten constant (Km). Of the substrates tested, catechol was the best substrate for PPO with a Km value of 2.2 mM. The optimum pH for PPO activity was found to be 7. The enzyme showed high activity over a broad pH range of 4 - 8. The optimal pH and temperature for enzyme activity were found to be 7 and 40-45 °C, respectively. km value for hawthorn PPO is calculated 22 mM for catechol and 6.7 mM for pyrogallol and 9.7 mM for L-dopa. As can be seen, affinity of PPOs for various substrates varies widely. The enzyme showed a broad activity over a broad pH and temperature range. The thermal inactivation studies showed that the enzyme is heat resistant. The enzyme showed the highest activity toward pyrogallol and no activity toward tyrosine. Of the inhibitors tested, the most potent inhibitors were kojic acid, cysteine and glycine , respectively


2013 ◽  
Vol 2013 ◽  
pp. 1-6 ◽  
Author(s):  
Ponnuswamy Vijayaraghavan ◽  
R. Raja Primiya ◽  
Samuel Gnana Prakash Vincent

A bacterial isolate, Alcaligenes sp. secreting phytase (EC 3.1.3.8), was isolated and characterized. The optimum conditions for the production of phytase included a fermentation period of 96 h, pH 8.0, and the addition of 1% (w/v) maltose and 1% (w/v) beef extract to the culture medium. This enzyme was purified to homogeneity and had an apparent molecular mass of 41 kDa. The optimum pH range and temperature for the activity of phytase were found to be 7.0-8.0 and 60°C, respectively. This enzyme was strongly inhibited by 0.005 M of Mn2+, Mg2+, and Zn2+. In vitro studies revealed that the phytase from Alcaligenes sp. released inorganic phosphate from plant phytates. Phytase released 1930 ± 28, 1740 ± 13, 1050 ± 31, 845 ± 7, 1935 ± 32, and 1655 ± 21 mg inorganic phosphate/kg plant phytates, namely, chick pea, corn, green pea, groundnut, pearl pea, and chick feed, respectively.


1953 ◽  
Vol 31 (1) ◽  
pp. 28-32 ◽  
Author(s):  
A. C. Blackwood

One hundred and fourteen bacterial cultures representing most of the species in the Bacillus genus were tested for the production of extracellular barley gum cytase. Assays were made on shake-flask cultures grown on a medium containing glucose and yeast extract. Although all the organisms had some enzymatic activity, certain strains of Bacillus subtilis gave the best yields of cytase. On a medium with asparagine as the sole nitrogen source even higher yields were obtained. The crude cytase preparations were stable and after freeze-drying most of the original activity remained.


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