De-hairing protease production by an isolated Bacillus cereus strain AT under solid-state fermentation using cow dung: Biosynthesis and properties

Abstract

Agro-industrial residues and cow dung were used as the substrate for the production of alkaline protease by Bacillus cereus strain AT. The bacterial strain Bacillus cereus strain AT produced a high level of protease using cow dung substrate (4813 ± 62 U g(-1)). Physiological fermentation factors such as the incubation time (72 h), the pH (9), the moisture content (120%), and the inoculum level (6%) played a vital role in the enzyme bioprocess. The enzyme production improved with the supplementation of maltose and yeast extract as carbon and nitrogen sources, respectively. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis and zymogram analysis of the purified protease indicated an estimated molecular mass of 46 kDa. The protease enzyme was stable over a temperature range of 40-50 °C and pH 6-9, with maximum activity at 50 °C and pH 8. Among the divalent ions tested, Ca(2+), Na(+) and Mg(2+) showed activities of 107 ± 0.7%, 103.5 ± 1.3%, and 104.6 ± 0.9, respectively. The enzyme showed stability in the presence of surfactants such as sodium dodecyl sulfate and on various commercially available detergents. The crude enzyme effectively de-haired goat hides within 18 h of incubation at 30 °C. The enzymatic properties of this protease suggest its suitable application as an additive in detergent formulation and also in leather processing. Based on the laboratory results, the use of cow dung for producing and extracting enzyme is not cumbersome and is easy to scale up. Considering its cheap cost and availability, cow dung is an ideal substrate for enzyme bioprocess in an industrial point of view.

Effect of Cow Dung, Biogas Slurry and Vermicompost on Phosphorus Adsorption Behavior of Soil

“…Fresh cow dung contains unstable OMs [17] which are very poor substrate for adsorption; even it inhibits adsorption by blocking adsorption sites [18]. However, these unstable OMs were converted to stable substrate [19] following PO 4 3-adsorption with time.…”

Effect of activators and inhibitors on extracellular thermostable alkaline protease isolated from Bacillus subtilis obtained from eastern province of Saudi Arabia

“…Al-Khaldi and Al-Abdalall 235 Results proved that magnesium ions (Mn +2 ) was the ideal ions which activated enzyme reaction; these findings agreed with that found by Sharaf and Al-Fadel (2013) while the result contradict those of Sharaf and AlFadel (2013) and Vijayaraghavan et al (2014b) who found that calcium ions were the best. Sathyavrathan and Krithika (2014) found that Cu +2 ions was the best for this reaction.…”

“…Najafi et al (2005) and Mukesh et al (2012) explained that, alkaline enzyme hydrolyses collagen during incubation for 3 h and help in hair removing. Macedo et al (2005) could completely remove skin hair by using keratinase extracted from B. subtilis S14 after 9 h incubation, but Bholay et al (2012) proved that at 12 and 18 h, if incubated at 37°C skin hair can also be removed and this was also mentioned by Vijayaraghavan et al (2014b). Verma et al (2011) mentioned that, alkaline protease could remove the epidermal layer with hair by skin treatment after 24 h, while Prabhavathy et al (2013) stated that the enzyme could remove skin hair after 24 h, as the enzyme destroy the collagen and facilitate hair remove without any skin damage.…”

Production of Industrially Important Enzymes by Thermobacilli Isolated From Hot Springs of India

“…55 °C and alkaline pH conditions. A number of studies have indicated that the optimum production of protease enzyme occur at identical alkaline pH under different temperature conditions [39,40]. According to Hadder et al [41], protease enzyme having high temperature and alkaline pH activity make it ideal for detergent industries.…”