bacillus thuringiensis strain ng, a novel isolated strain for production of various polyhydroxyalkanoates

Introduction: microbial biopolymers such as polyhydroxyalkanoates (pha) are proper alternatives for petroleumderived plastics. these biopolymers have many advantages over conventional plastics such as biodegradability, environmental friendly and infinite as a renewable resource. therefore, our study was aimed to isolate a bacterial strain capable of producing polyhydroxybutyrate (phb; a highly applicable type of pha). materials and methods: to this aim, a total of 6 phaproducing bacteria were isolated from waste water exit site of a brewery factory. the 6 isolates were studied by sudan blackstaining technique and the most stained isolate was selected for further studies. next, the selected isolate was identified based on morphological, biochemical and phylogenetic analyses. finally, the ability of strain in producing phb as well as other phas was analyzed via gcms technique. results: strain ng had the highest yield of phb, according to sudan blackstaining technique and it was selected for further studies. the strain ng was identified as a new strain of bacillus thuringiensis. according to gcms results, this strain was able to produce phb as well as 4 other phas including hexadecanoic acid methyl ester, octadecanoic acid methyl ester, tetradecanoic acid methyl ester, 8octadecenoic acid methyl ester. discussion and conclusion: it was the first report on producing various phas at the same time by a strain of bacillus thuringiensis.