In this work four agroindustrial cakes were used as raw material both for production of enzyme pools containing amylases and accessory hydrolases by solidstate fermentation (SSF) and for cold starch hydrolysis. Eight fungal strains from the genera Aspergillus and Penicillium were screened for enzyme production, and their enzyme extracts were then evaluated in the hydrolysis of raw cakes. Babassu cake was the most suitable raw material for endoamylases, exoamylases and proteases production. The highest activities of these three enzymes were produced by A. awamori IOC-3914 (29.8 U g -1 ), A. wentii (47.8 U g -1 ) and P. verrucosum (27.5 U g -1 ), respectively. Regarding cellulases and xylanases, maximum activities (12.8 and 598.0 U g -1 , respectively) were obtained by A. awamori IOC-3915 in castor seed residue. Saccharification studies showed a flexible applicability of the raw extracts to hydrolyze different cakes. A maximum total reducing sugars concentration of 13.9 g L -1 was obtained from babassu cake using a raw enzyme extract produced by A. awamori IOC-3915, without any concentration or purification steps. The present results demonstrate that a low-cost SSF process can supply enzyme extracts with a high potential for application in the cold hydrolysis of raw starch from agroindustrial cakes.
Amylases constitute one of the most important groups of industrial enzymes, presenting several applications, such as in the food, textile, and ethanol manufacturing. In this work, a starchy residue from the Brazilian agroindustry, namely babassu cake, was used for the production of amylases by solid-state fermentation and for obtaining sugar hydrolysates, which can be used as building blocks for future bioconversions. Eight filamentous fungi from the genera Aspergillus and Penicillium were screened. Regarding amylase production, A. awamori strains showed well-balanced endoamylase and exoamylase activities, while A. wentii produced an amylolytic complex much richer in the endo-acting enzymes. Simultaneous liquefaction and saccharification using the crude enzyme extracts from the four most promising fungal strains was then investigated applying DOE techniques. The highest total reducing sugar content (24.70 g L −1 ) was obtained by the crude extract from A. awamori IOC-3914, corresponding to a hydrolysis yield of 52% of total starch in the cake, while A. awamori IOC-3915 produced the most appropriate extract in terms of glucose release (maximum of 5.52 g L −1 ). Multivariate analysis of the DOE studies indicated that these extracts showed their best performance at 50-57°C under acid conditions (pH 3.6-4.5), but were also able to act satisfactorily under milder conditions (36°C and pH 5.0), when TRS and glucose released were about 65% of the maximum values obtained. These data confirm the high potential of the enzyme extracts under study for cold hydrolysis of starch.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
hi@scite.ai
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.