Abstract:Waste frying oil, which not only harms people's health but also causes environmental pollution, can be a good alternative to partially substitute petroleum diesel through transesterification reaction. This oil contained 8.8 % of free fatty acids, which cause a problem in a base-catalyzed process. In this study, synthesis of biodiesel was efficiently catalyzed by the covalently immobilized Talaromyces thermophilus lipase and allowed bioconversion yield up to 92 % after 24 h of reaction time. The optimal molar r… Show more
“…). When exceeding a molar ratio of 8:1, the rate of methanolysis obtained with the free enzyme becomes significantly lower than with immobilized lipase, probably owing to the direct contact between methanol droplets and lipase molecules and thereby more strongly deactivating the free enzyme (Romdhane et al, ). In addition, the immobilized lipase gave a higher FAME content as compared with its nonimmobilized counterpart for all substrate ratios.…”
Section: Resultsmentioning
confidence: 99%
“…At the end of each batch, the immobilized lipase was recovered by centrifugation. The immobilized lipase was washed with tert ‐butanol to remove any substrate or product (eventually glycerol) retained in the matrix (Romdhane et al, ). After that, it was vacuum filtered and placed in a desiccator containing silica gel.…”
Oil from palm oil mill effluents (POME) was utilized as the substrate for fatty-acid methyl ester (FAME) production using lipase from palm fruit immobilized to chitosan beads as a catalyst. The optimal reaction conditions consisted of a methanol-to-oil ratio of 6:1 mol mol −1 , 6 g immobilized lipase per 10 g of POME oil at an incubation temperature of 35 C, a mixing speed of 200 rpm (with a 5 cm orbital diameter), and a reaction time of 24 h. Under optimal conditions, the FAME content was 93.6% methanol-free basis. In addition, immobilized lipase retained 90.5% after six subsequent reaction cycles (compared with the FAME content of the first batch). The properties of FAME were characterized and found to fulfill both Thailand and ASTM standards.Keywords Esterification Á Fatty-acid methyl ester Á Immobilized enzyme Á Palm lipases Á Palm oil mill effluent Á POME Á Transesterification J Am Oil Chem Soc (2018) 95: 1373-1384.
“…). When exceeding a molar ratio of 8:1, the rate of methanolysis obtained with the free enzyme becomes significantly lower than with immobilized lipase, probably owing to the direct contact between methanol droplets and lipase molecules and thereby more strongly deactivating the free enzyme (Romdhane et al, ). In addition, the immobilized lipase gave a higher FAME content as compared with its nonimmobilized counterpart for all substrate ratios.…”
Section: Resultsmentioning
confidence: 99%
“…At the end of each batch, the immobilized lipase was recovered by centrifugation. The immobilized lipase was washed with tert ‐butanol to remove any substrate or product (eventually glycerol) retained in the matrix (Romdhane et al, ). After that, it was vacuum filtered and placed in a desiccator containing silica gel.…”
Oil from palm oil mill effluents (POME) was utilized as the substrate for fatty-acid methyl ester (FAME) production using lipase from palm fruit immobilized to chitosan beads as a catalyst. The optimal reaction conditions consisted of a methanol-to-oil ratio of 6:1 mol mol −1 , 6 g immobilized lipase per 10 g of POME oil at an incubation temperature of 35 C, a mixing speed of 200 rpm (with a 5 cm orbital diameter), and a reaction time of 24 h. Under optimal conditions, the FAME content was 93.6% methanol-free basis. In addition, immobilized lipase retained 90.5% after six subsequent reaction cycles (compared with the FAME content of the first batch). The properties of FAME were characterized and found to fulfill both Thailand and ASTM standards.Keywords Esterification Á Fatty-acid methyl ester Á Immobilized enzyme Á Palm lipases Á Palm oil mill effluent Á POME Á Transesterification J Am Oil Chem Soc (2018) 95: 1373-1384.
“…F18 showed an activity level of 1.04 U/ml. Romdhane et al (2013) obtained enzymatic activity of 9.8 U/ml for the purified lipase produced by the fungus T. thermophilus. Thus, the endophytic fungus Talaromyces sp.…”
Obtaining bioactive metabolites from endophytic microorganisms has become increasingly more interesting in the last few decades, since endophytes are known for their biotechnological potential. However, studies involving endophytic microbiota from tropical hosts are still scarce. In this study, the production of bioactive metabolites from endophytic fungi isolated from Amazonian plants were evaluated. Two fungi (Talaromyces sp. F15 and Aspergillus sp. F18) isolated from Myrcia guianensis (Myrtaceae) and one (Penicillium sp. F3) isolated from Euterpe precatoria (Arecaceae) were analysed. The fungi were cultivated in liquid medium and their metabolites were tested for antimicrobial, antioxidant and cytotoxic activity. Amylase, cellulase and lipase production, as well as biosurfactant production, were also evaluated. The metabolites of Aspergillus sp. F18 showed 69.4% antioxidant activity against DPPH free-radical molecules and cytotoxic activity against A. salina. Penicillium sp. F3 showed cytotoxic activity and stood out as the best amylase producer (31 U/ml). Talaromyces sp. F15 was the best lipase producer (4.5 U/ml) and the best biosurfactant source, with 33.3% emulsification index. These Amazonian host-associated fungi showed biotechnological potential, which are believed should be further investigated in order to elucidate the chemical structure of the metabolites responsible for the activities described here, as well as optimize their production.
“…90–92 While these immobilized enzymes show enhanced activity and allow for reuse, studies have shown that the support material can further improve the activity of commercially available enzymes through enzyme–material interactions. 93,94 Recent research on immobilized lipases for waste oil valorization commonly explores silica supports, 86,94–96 resins, 97–100 biological supports (e.g., chitosan), 101,102 and nanomaterials. 103–107 Fig.…”
Section: Applications Of Immobilized Enzymes In Food Waste Stream Valmentioning
Food processing generates byproduct and waste streams rich in lipids, carbohydrates, and proteins, which contribute to its negative environmental impact. However, these compounds hold significant economic potential if transformed into revenue streams such as biofuels and ingredients. Indeed, the high protein, sugar, and fat content of many food waste streams makes them ideal feedstocks for enzymatic valorization. Compared to synthetic catalysts, enzymes have higher specificity, lower energy requirement, and improved environmental sustainability in performing chemical transformations, yet their poor stability and recovery limits their performance in their native state. This review article surveys the current state-of-the-art in enzyme stabilization & immobilization technologies, summarizes opportunities in enzyme-catalyzed valorization of waste streams with emphasis on streams rich in mono- and disaccharides, polysaccharides, lipids, and proteins, and highlights challenges and opportunities in designing commercially translatable immobilized enzyme systems towards the ultimate goals of sustainable food production and reduced food waste.
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