In the present study, seven axenic fresh water microchlorophytes were isolated and identified as Tetradesmus dimorphus (NEIST BT-1), Chlorella sorokiniana (NEIST BT-2), Desmodesmus sp. (NEIST BT-10), Selenastrum sp. (NEIST BT-A6), Tetradesmus obliquus (NEIST BT-A1), Tetradesmus sp. (NEIST BT-A10), and Asterarcys sp. (NEIST BT-A15) based on morphological and molecular characterization. Their potential to be used as biodiesel feedstock was evaluated depending on their growth characteristics and lipid profiles. Among the seven isolates, NEIST BT-2 was found to be the most promising candidate owing to its high biomass yield (2.09 ± 0.037 g L −1) and lipid productivity (107.60 ± 10.175 mg L −1 day −1). The gas chromatography analysis confirmed the presence of significant amounts of palmitic acid, linoleic acid, linolenic acid, and oleic acid in the isolate which are some of the major constituents of any biodiesel. The predictive models showed that the biodiesel from this isolate has ideal fuel properties which comply with the ASTM D6751 and EN 14214 specifications. These findings demonstrate that NEIST BT-2 can be used as a prospective candidate for consideration of large-scale biodiesel production.

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The aim of the study was to purify and characterize cellulase from a previously isolated Novosphingobium sp. strain Cm1 and to evaluate its waste hydrolysis and bio-stoning efficiency. Materials and Methods:There is a growing demand for cellulase, a multipurpose enzyme widely used in industrial applications. Here, we purified cellulase from Novosphingobium sp. Cm1 by cellulose chromatography. SDS-PAGE revealed a molecular mass of 25 kDa. After 18-fold purification, the cellulase had an activity of 31.4 U/mg at pH of 5 and 40°C, and it retained activity at a wide range of pH and temperatures. The presence of Fe 2+ and Co 2+ boosted the enzyme activity by 57% and 25% respectively. The hydrolysing capacity of the strain towards cellulosic material was assessed for two paper types and the highest activity (2.6 ± 0.05 U/ml) was found with filter paper as the sole carbon source.Alterations in the structure of the papers as a result of bacterial hydrolysis were confirmed by scanning electron microscope and Fourier-transform infrared spectroscopy. The strain was also tested for its potential in various industrial applications and exhibited pectinolytic activity (6.78 ± 0.68 U/ml), xylanolytic activity (0.22 ± 0.14 U/ml) and bio-stoning ability. Conclusion:The highly active purified cellulase has a broad pH and temperature range. The strain possesses waste-hydrolysing ability, pectinolytic and xylanolytic ability along with bio-stoning capacity. Significance and Impact of the Study:The efficacy and versatility of the enzyme from Novosphingobium sp. Cm1 make it an excellent candidate for diverse industrial applications.