Statistical methodologies for enhancing lipase production from Aspergillus Niger and using biologically treated cottonseed waste in animal nutrition.

Lipases are industrially valuable biocatalysts; mainly microbial lipases, hence screening and production of lipases from various microbial strains are constantly emerging to meet the needs of the pharmaceutical and food industry sectors. More recently, different cost-effective and efficient techniques to improve lipase synthesis in microbial strains have been investigated. This article attempts to connect the production of lipases from a local isolate Aspergillus niger MK377324 under solid-state fermentation with agro-industrial waste as substrate. Plackett-Burman (PB) and central composite statistical designs (CCD) were employed to examine the effect of multiple factors such as carbon and nitrogen sources, pH, and temperature on the production of lipase from A. niger. The results showed that cottonseed waste was the optimal substrate for A. niger lipase production, while peptone, K2HPO4, and CuSO4 at final concentrations of 5.0, 2.0, 0.5, and 0.015 g/L significantly increased lipase synthesis, yielding 21.42 ± 1.3 U/g ds. Agro-industrial byproducts, which are widely available, can serve an important role in ruminant nutrition. As a result, the residual biomass of the biologically processed cottonseed waste was observed to have high protein content of 29.6% and a considerable percentage of essential amino acids such as lysine (1.28%), therionine (1.04%), and methionine (0.44%), while the crude fibre was decreased from 18.3 to 15.6%, with the potential to significantly improve the nutritional value of animal feed. Overall, using cottonseed waste as a substrate and feed source represents a promising solution to environmental and nutritional challenges. The main advantage of using lipase as a biocatalyst in a variety of organic transformations is that it may also be utilized to produce biodiesel.