AES Bioflux, 2013, Volume 5, Issue 1. http://www.aes.bioflux.com.ro 23 AES BIOFLUX Advances in Environmental Sciences - International Journal of the Bioflux Society β-Glucosidase production by Aspergillus niger van Tieghem using submerged fermentation of pineapple waste Carol S. Maguinsay, Franco G. Teves Molecular Biology and Biotechnology Research Laboratory, Department of Biological Sciences, College of Science and Mathematics, Mindanao State University-Iligan Institute of Technology, Iligan City, Lanao del Norte, Philippines. Corresponding author: C. S. Maguinsay, carsoc@yahoo.com Abstract. This study aimed to assess the potential of pineapple waste as substrate for β-Glucosidase production by Aspergillus niger under submerged fermentation. β-Glucosidase activities of crude enzyme extract from cultures maintained with pineapple substrate and with the commercial substrate carboxymethyl cellulose (CMC) were assayed and compared. The assay conducted at different periods of fermentation shows that enzymatic activities were generally higher on cultures maintained with CMC. However, β-Glucosidase activities on cultures supplemented with pineapple substrate had been found to be functional at a higher temperature (60°C). In conclusion, pineapple substrate has been demonstrated to be capable of inducing the synthesis of β-Glucosidase enzymes. Key Words: β-Glucosidase, Aspergillus niger, submerged fermentation, pineapple waste. Introduction. The pursuit of finding alternative energy source due to the subsiding reserves of fossil fuels had already engaged bioconversion of cellulose – a renewable carbon source abundant in the environment that compose plant materials in majority (Duff et al 1985; Heck et al 2002; Ojumu et al 2003). However, the conversion of cellulose into products having commercial value (e.g. bioethanol) calls for efficient and economical methods to lower the expenditure of the entire operation (Mandels et al 1971; Macris 1984). Over decades, it appears that the improvement of cellulase production technology is the most promising means to enhance biofuel production and several industrial processing. Cellulase it is a multienzyme complex capable of decomposing plant substrates. One component of the cellulase enzyme system is β-Glucosidase (EC 3.2.1.21) and it works together with endoglucanase and exoglucanase to break down cellulose in the plant cell walls (Yun et al 2001; Lynd et al 2002). The synthesis of β-Glucosidase and other components of cellulase enzymes may be carried out in cultures of cellulolytic microorganisms. In fungal cultures, such enzymes can be produced extracellularly by the fungus itself to aid the digestion of insoluble substrates such as cellulose (Hurst et al 1977; Chaudhary & Tauro 1982; Pandey et al 1999). β-Glucosidase basically plays a significant role in several biological processes occuring in nature such as beta-glucan synthesis during development of cell wall, pigmentation, fruit ripening and defense mechanism. It is also the key enzyme component present in cellulase which is important in various biotechnological processing of food products, textile refining, production of pulp and paper, improvement of oil recovery, waste treatment, and especially in biofuel production (Singhania et al 2012; Rajoka 2004). The current setting of β-Glucosidase production is focused on utilizing plant biomass, agro-industrial and municipal wastes. Such materials are used as substrates in attempting to reduce the expensive enzyme production cost, which has been a major economic limitation not only of biofuel production but also of other industrial processes