Production and optimization of lipase using Aspergillus niger MTCC 872 by solid-state fermentation

Abstract

Background: Lipases are serine hydrolases that degrade triglycerides, an attribute that treasures wide applications in biodiesel production, detergent, chemical industries, etc. The most sought after the application is in the high quality and economical production of biodiesel under mild reaction conditions and simplified product separation. For the said application, fungal lipases are ideal catalysts that could effectively catalyze esterification and transesterification reactions with their specific ability to release fatty acids from 1, 3 positions of acylglycerols. Results: In the present work, to facilitate bulk synthesis, lipase production using Aspergillus niger MTCC 872 was studied by solid-state fermentation (SSF). The chosen fungal strain was evaluated for lipase production using a mixture of agroindustrial substrates viz. rice husk, cottonseed cake, and red gram husk in various combinations at flask level. Tri-substrate mixture (rice husk, cottonseed cake, and red gram husk) combined in the ratio of 2:1:1 has shown the maximum lipase activity 28.19 U/gds at optimum cultivation conditions of temperature 40°C, moisture content 75% (v/w), pH 6.0 and initial spore concentration of 5.4 million spores per mL. Further studies were performed for scale-up of lipase from flask level to lab scale using tray fermenter. Lipase activity was found to be 24.38 U/gds and 21.62 U/gds for 100 g and 1000 g substrate respectively. Conclusion: This is the first report on the production of lipase from Aspergillus niger MTCC 872 using tri-substrate mixture of rice husk (RH), cottonseed cake (CSC), and red gram husk (RGH). Moreover, comparison between individual, binary, and tri-substrate mixture was carried out for which the highest lipase activity was observed for tri-substrate mixture. In addition, comparable results were found when scale-up was performed using tray fermenter. Thus, the current work signifies usage of agro-industrial residues as substrates for enzyme production by solid-state fermentation process as an effective alternative to submerged fermentation for industrial applications.

Detecção De Esterase E Lipase Produzidas Por Fungos Filamentosos Isolados De Solos Da Caatinga / Detection of Esterase and Lipase Produced by Filamentous Fungi Isolated of Caatinga Soil

“…Outros autores que também conseguiram obter a enzima hidrolítica a partir da mesma amostra de forma satisfatória utilizaram resíduos agroindustriais em seu meio de produção. O uso de resíduos contribui para a biossíntese de baixo custo, pois são rejeitos da extensa produção agrícola de países em desenvolvimento e o seu descarte é também um problema ambiental, e contribuem principalmente no fornercimento de nutrientes necessários para o crescimento das células microbianas (NEMA, PATNALA, MANDARI et al, 2019;TACIN, MASSI, FUNGARO et al, 2019;PRABANINGTYAS, PUTRI, UTAMI et al, 2018). Kumar, Rani, Gunaseeli et al (2017) utilizaram em seus estudos a fermentação sólida e submersa para produção da lipase pelo Aspergillus japonicus MF-1: óleo de amendoim associado a agentes redutores e oxidantes na fermentação sólida, que obteve o máximo de produção da enzima (266 U/g), enquanto que em fermentação submersa na presença de óleo medicinal sendo produzido cerca de 58% deste valor.…”

Molecular, physiological, and biochemical characterization of extracellular lipase production by Aspergillus niger using submerged fermentation

“…Isolates showed high heat tolerance at different temperatures with the highest enzymatic production occurred at 40 • C. At 45 • C, isolates were unable to grow or produce the enzyme due to the mutilation of cellular proteins (Singh & Mukhopadhyay, 2012), except for A. niger MH078571 and A. niger MH079049, which exhibited the potential of lipase production and were resistant to high temperatures (Oliveira, Watanabe & Vargas, 2012;Niaz et al, 2014). Higher temperatures that enhance lipase synthesis and reduce A. niger growth have been reported previously (Nema et al, 2019). In addition, different temperatures have been reported for the maximum lipase activity such as at 30 • C for P. chrysogenum, which is the natural growth temperature of fungi (Ramani et al, 2010), at 37 • C for A. terreus (Gulati, Saxena & Gupta, 1999) and R. oryzae (Yuzbashev, Yuzbasheva & Vibornaya, 2012).…”

Effects of Solid State Fermentation on some Physicochemical and Nutritional Properties of Post-Harvest Cowpea (Virgna unguiculata (L)Walp) Leavesv

“…This was attributed to the preference of Aspergillus niger for relatively lower pH for its growth and metabolism. According to Nema et al, (2019), maximum lipase activity of 25.12 U/gds was observed at pH 6, while further increment gave a significant reduction in lipase activity, at pH 7.5 (7.14 U/gds).…”