Isolation of local strain of Bacillus sp. SM-11, producing PHB using different waste raw as substrate

Abstract

Polyhydroxyalkalonates (PHAs) have numerous industrial and medical applications, is being used in various medical applications such as scaffold, suture, heart valve and drug delivery etc. Poly 3-hydroxy butyrate (PHB) is the most common and important family member of PHAs. The bacterial strains which are able to produce higher quantities of PHA using low-cost substrates are always in demand. In the present study, a local strain of Bacillus sp. SM11 isolated from soil was screened for ability to produce biopolymer i.e., PHB (polyhydroxybutyrate). Various factors which have been found to have an impact on PHB production by the selected capable bacterial isolates were optimized viz., organic waste source (soya extract, whey, molasses, corn extract, and distillery waste liquor), nitrogen source (peptone, beef extract, yeast extract, ammonium chloride, and ammonium sulphate), pH, and trace elements. An optimized PHB yield of 3.53g/L was obtained using whey as a source of carbon, added with 1% of yeast extract as a nitrogen source at pH 6.0 in presence of calcium as a trace element. The outcome of the present study indicates that isolate is among one of the high PHB producing microorganism, using whey as a carbon source.