Efficient and low-cost alternative of lipase concentration aiming at the application in the treatment of waste cooking oils

Biotechnological potential of Lacticaseibacillus paracasei Shirota for bioemulsifier, bacteriocin and lipase production

This study aimed to evaluate the biotechnological potential of Lacticaseibacillus paracasei Shirota to produce biosurfactants/bioemulsifiers, lipase, and bacteriocins. The production of biosurfactants/bioemulsifiers was evaluated through a central composite rotational design (CCRD) 22. L. paracasei produced bioemulsifiers using MRS supplemented with 4.8% glycerol and pH 6 or 7. In addition, the culture supernatants of L. paracasei were tested for antioxidant, antidiabetic, and lipolytic activities. The tested supernatants did not exhibit antioxidant activity. On the other hand, they showed inhibitory activity for amyloglucosidase (20.7% and 23.9%) and lipolytic activity (16.12 and 19.00 U/mL). In addition, a CCRD 23 was performed to evaluate the production of bacteriocins. The peptone and lactose concentration variables, as well as pH positively influenced the production of bacteriocins by L. paracasei. In conclusion, L. paracasei is a viable source of antidiabetic metabolites, bacteriocins, bioemulsifiers, and lipase, suggesting that they are promising to be applied in the pharmaceutical, cosmetic, environmental, food, and biomedical industries.

Progress in Enzymatic Biodiesel Production and Commercialization

Enzymatic biodiesel production has attracted tremendous interest due to its well-recognized advantages. However, high enzyme costs limit the application of enzymatic processes in industrial production. In the past decade, great improvements have been achieved in the lab and the industrial scale, and the production cost of the enzymatic process has been reduced significantly, which has led to it being economically competitive compared to the chemical process. This paper summarizes the progress achieved in enzymatic biodiesel research and commercialization, including reducing enzyme cost, expanding low-quality raw materials, and novel reactor designs. The advantages and disadvantages of different enzymatic processes are also compared.

Reactional ultrasonic systems and microwave irradiation for pretreatment of agro-industrial waste to increase enzymatic activity

Pretreatment of keratinous residues using an ultrasonic reaction system provides greater enzymatic production in less time. This is a promising technology for measuring enzyme activity and microwave processes. In the present work, an ultrasonic probe reaction system was used to evaluate the potential of swine hair pretreatment. The pretreated material was submerged with non-pretreated residues for 9 days to obtain the enzyme. Enzyme activity was measured in the extracts obtained using the ultrasonic probe, ultrasonic bath, and microwave. We also used the enzymatic concentration technique with NaCl and acetone. Homemade enzymatic extracts were evaluated for their ability to degrade swine hair and chicken feathers by comparing them with the activities commercial enzymes. Macrobeads gave greater energy dissipation in less time, providing greater enzyme activity (50.8 U/mL over 3 days). In terms of waste degradation, non-pretreated swine hair was more promising. The ultrasonic probe reaction system had the potential to evaluate increased enzyme activity (38.4% relative activity) and the enzyme concentration increased activity by 53.5%. The homemade enzymatic extract showed promise for degradation of keratinous residues.

Concentration of Lipase from Aspergillus oryzae Expressing Fusarium heterosporum by Nanofiltration to Enhance Transesterification

Nanofiltration membrane separation is an energy-saving technology that was used in this study to concentrate extracellular lipase and increase its total activity for biodiesel production. Lipase was produced by recombinant Aspergillus oryzae expressing Fusarium heterosporum lipase (FHL). A sulfonated polyethersulfone nanofiltration membrane, NTR-7410, with a molecular weight cut-off of 3 kDa was used for the separation, because recombinant lipase has a molecular weight of approximately 20 kDa, which differs from commercial lipase at around 30 kDa for CalleraTM Trans L (CalT). After concentration via nanofiltration, recombinant lipase achieved a 96.8% yield of fatty acid methyl ester (FAME) from unrefined palm oil, compared to 50.2% for CalT in 24 h. Meanwhile, the initial lipase activity (32.6 U/mL) of recombinant lipase was similar to that of CalT. The composition of FAME produced from recombinant concentrated lipase, i.e., C14:1, C16:0, C18:0, C18:1 cis, and C18:2 cis were 0.79%, 34.46%, 5.41%, 45.90%, and 12.46%, respectively, after transesterification. This FAME composition, even after being subjected to nanofiltration, was not significantly different from that produced from CalT. This study reveals the applicability of a simple and scalable nanofiltration membrane technology that can enhance enzymatic biodiesel production.

Fusarium oxysporum and Aspergillus sp. as Keratinase Producers Using Swine Hair From Agroindustrial Residues

Technological processes mediated by microorganisms and enzymes are promising alternatives for treatment of recalcitrant residues. Keratinases hydrolyze keratin, the primary component of some wastes generated in many industrial activities. The present study was designed to evaluate strategies for obtaining keratinases produced by fungi using submerged fermentation and two residues as substrates, chicken feathers and swine hair. Two fungi isolated from feather residues showed potential for keratinase production, Fusarium oxysporum and Aspergillus sp. These were subjected to submerged fermentation using chicken feathers and swine hair prepared in three conditions (microbial concentration reduction, sterilization and hydrogen peroxide). The residual mass was quantified and tested for keratinase production. The most potent enzymatic extract was used in the precipitation technique with salts and organic solvents. The best results of enzymatic activity were obtained using F. oxysporum, on the 6thday of fermentation, obtaining 243.25 U mL^–1 using sterilized swine hair as the substrate. Aspergillus sp. showed the highest keratinolytic activity on the 9thday, 113.50 U mL^–1 using feathers as the substrate. The highest degradation percentage was 59.20% (w/w) in swine hair and the precipitation technique, with relative activities close to 50%. The results are promising for the application of residues and microorganisms in biotechnological processes of economic and environmental interest.

Advanced oxidation processes applied for color removal of textile effluent using a home-made peroxidase from rice bran

Enzymes are becoming tools in industrial processes because of several advantages, including activity in mild environmental conditions, and high specificity. Peroxidase, for one, stably oxidizes several substrates. The present study aimed to develop advanced oxidation processes (AOP), using non-commercial rice bran peroxidase to remove color and toxicity of synthetic textile wastewater. Using a microwave and shaker system, we obtained 38.9% and 100% of effluent color removal after peroxidase treatment, respectively. In addition, the shaker system decants residual dye particles through filtration, providing the textile industry with an economical and environmentally viable alternative to effluent treatment. In toxicity tests results, both treatment systems damaged the used genetic material. This damage occurs because of industrial discharge of wastewater into water bodies; effluent dilution reduced this damage. The data suggest that peroxidase as a textile effluent treatment has potential uses in industrial processes, because rice bran peroxidase has demonstrated affinity with dyes.