Utilization of xylose enriched extract from spent lemongrass hydrolysate for clavulanic acid production using Streptomyces clavuligerus (MTCC 1142).

The main goal of this study was to provide possible alternative production medium containing xylose enriched spent lemongrass hydrolysate with glycerol as a feedstock and corn gluten meal as a nitrogen source for their ability to support the cell growth of the Streptomyces clavuligerus MTCC 1142 for the production of clavulanic acid. The xylose was extracted from spent lemongrass by using 0.25% dilute nitric acid and further partial purification of acid spent hydrolysate was performed using ion exchange resin. The method was optimized using xylose enriched hydrolysate as feed stock combined with glycerol at ratio 1:1 and growing the selected strain aerobically in media at neutral pH containing 5 mM phosphate ion concentration and using corn gluten meal as a nitrogen source, fermenting at a temperature of 28-30 °C for 96 h and 0.59 g/L clavulanic acid was effectively produced. These results demonstrate the feasibility of using spent lemongrass as feedstock for the cultivation of S. clavuligerus to produce clavulanic acid.

Recent advances in biodiesel production: Challenges and solutions.

Mono alkyl fatty acid ester or methyl ethyl esters (biodiesel) are the promising alternative for fossil fuel or petroleum derived diesel with similar properties and could reduce the carbon foot print and the greenhouse gas emissions. Biodiesel can be produced from renewable and sustainable feedstocks like plant derived oils, and it is biodegradable and non-toxic to the ecosystem. The process for the biodiesel production is either through traditional chemical catalysts (Acid or Alkali Transesterification) or enzyme mediated transesterification, but as enzymes are natural catalysts with environmentally friendly working conditions, the process with enzymes are proposed to overcome the drawbacks of chemical synthesis. At present 95% of the biodiesel production is contributed by edible oils worldwide whereas recycled oils and animal fats contribute 10% and 6% respectively. Although every process has its own limitations, the enzyme efficiency, resistance to alcohols, and recovery rate are the crucial factors to be addressed. Without any benefit of doubt, production of biodiesel using renewable feedstocks and enzymes as the catalysts could be recommended for the commercial purpose, but further research on improving the efficiency could be an advantage.