The galactomannan-based gel from Cassia grandis seeds was used to incorporate Penicillium sp. UCP 1286 and commercial collagenases. Experiments were carried out according to a 2³-full factorial design to identify the most significant parameters for the incorporation process. The pH of the incorporation solution (pH_i), stirring time (t), and initial protein concentration in the crude extract (PC_i) were selected as the three independent variables, and the efficiency of collagenase incorporation (E) and collagenolytic activity (CA) after 360 min as the responses. pH_i and PC_i showed positive statistically significant effects on E, while CA was positively influenced by pH_i and t, but negatively by PC_i. The fungi collagenase was released from the gel following a pseudo-Fickian behavior. Additionally, no <76 % of collagenase was efficiently incorporated into the gel retaining a high CA (32.5-69.8 U/mL). The obtained results for the commercial collagenase (E = 93.88 %, CA = 65.8 U/mL, and n = 0.10) demonstrated a pseudo-Fickian behavior similar to the fungi-collagenase. The results confirm the biotechnological potential of the gel as an efficient matrix for the incorporation of catalytic compounds; additionally, the incorporation of collagenases was achieved by retaining the proteases CA and releasing them in a controlled manner.

Whey, a large-scale dairy industry by-product, can be converted into whey protein concentrate (WPC), providing a cost-effective nutrient-rich substrate for microbial fermentation. We investigated protease production by Aspergillus oryzae using WPC as the sole substrate in submerged fermentation. Following fermentation, the protease was purified sequentially from the crude extract by salting-out, which yielded a substantial purification factor (~39), and subsequent ion-exchange chromatography. The non-adsorbed chromatographic fraction showed the highest protease activity (92.6 U/mL) and revealed one main protein band ~45 kDa via SDS-PAGE. Enzyme characterization demonstrated activity across neutral-to-alkaline conditions, optimal at pH 9.0 and 37 °C, with stability maintained between 30 °C and 37 °C. The enzyme was classified as a serine protease based on strong inhibition by PMSF and SDS; its activity was also inhibited by Zn²⁺, Mg²⁺, and K⁺, but enhanced by Ca²⁺. This work validates WPC as an efficient substrate for protease production by A. oryzae and presents a promising strategy for valorizing industrial by-products through sustainable biotechnology.

Oil cakes, valuable co-products of the oil industry, are rich in bioactive and nutritional compounds, making them suitable for biotechnological processes that lower costs and reduce environmental impact. These versatile materials are commonly used as substrates for microbial enzyme production, particularly in the context of sustainable, cost-effective protease synthesis. This review surveyed the application of oil cakes as substrates for microbial protease production, focusing on studies published between 2013 and 2023 from databases such as ScienceDirect, PubMed, Web of Science, and Scopus. After screening, 30 studies were deemed eligible from an initial pool of 1602 articles. Nineteen different oil cake types were identified, with soybean cake being the most utilized. The studies highlighted the effectiveness of oil cakes in supporting microbial protease production, particularly with species from the Aspergillus (fungi) and Bacillus (bacteria) genera. Despite the diversity of microorganisms and substrates explored, only a limited number of studies provided detailed compositional analyses of the oil cakes. Nonetheless, the review underscores the growing trend of using oil cakes as an economical and sustainable nutrient source for microbial protease production. Oil cakes, valuable co-products of the oil industry, are rich in bioactive and nutritional compounds, making them suitable for biotechnological processes that lower costs and reduce environmental impact. These versatile materials are commonly used as substrates for microbial enzyme production, particularly in the context of sustainable, cost-effective protease synthesis. This review surveyed the application of oil cakes as substrates for microbial protease production, focusing on studies published between 2013 and 2023 from databases such as ScienceDirect, PubMed, Web of Science, and Scopus. After screening, 30 studies were deemed eligible from an initial pool of 1602 articles. Nineteen different oil cake types were identified, with soybean cake being the most utilized. The studies highlighted the effectiveness of oil cakes in supporting microbial protease production, particularly with species from the Aspergillus (fungi) and Bacillus (bacteria) genera. Despite the diversity of microorganisms and substrates explored, only a limited number of studies provided detailed compositional analyses of the oil cakes. Nonetheless, the review underscores the growing trend of using oil cakes as an economical and sustainable nutrient source for microbial protease production.

Fungal bioactive compounds can be used by pharmaceutical, agricultural or food industries, and their discovery and identification is closely linked to the methodologies applied in the process. The current knowledge of filamentous fungi genome mining has shown that many genes encoding biosynthetic pathways are silenced, thus limiting their ability to produce metabolites under commonly used laboratory conditions. These biosynthetic pathways may produce substances with antimicrobial potential, but more specific conditions are needed for their activation. This review article shows that the treatment of these fungi with epigenetic modulators such as DNA methyltransferase (DNMT) inhibitors and/or histone deacetylase (HDAC) inhibitors is an approach capable of triggering activation of biosynthetic pathways previously silenced epigenetically. Due to the extensive metabolic diversity of filamentous fungi, epigenetic chromatin modulation appears to be an innovative methodology that can lead to great discoveries in the field of bioprospecting of compounds, not only antimicrobials, as well as to the proven possibility of maximizing the production of known compounds.