Optimization of lipase production using fungal isolates from oily residues.

Lipases are triacylglycerol hydrolases that catalyze hydrolysis, esterification, interesterification, and transesterification reactions. These enzymes are targets of several industrial and biotech applications, such as catalysts, detergent production, food, biofuels, wastewater treatment, and others. Microbial enzymes are preferable for large scale production due to ease of production and extraction. Several studies have reported that lipases from filamentous fungi are predominantly extracellular and highly active. However, there are many factors that interfere with enzyme production (pH, temperature, medium composition, agitation, aeration, inducer type, and concentration, etc.), making control difficult and burdening the process. This work aimed to optimize the lipase production of four fungal isolates from oily residues (Penicillium sp., Aspergillus niger, Aspergillus sp., and Aspergillus sp.). The lipase-producing fungi isolates were morphologically characterized by optical and scanning electron microscopy. The optimal lipase production time curve was previously determined, and the response variable used was the amount of total protein in the medium after cultivation by submerged fermentation. A complete factorial design 32 was performed, evaluating the temperatures (28 °C, 32 °C, and 36 °C) and soybean oil inducer concentration (2%, 6%, and 10%). Each lipase-producing isolate reacted differently to the conditions tested, the Aspergillus sp. F18 reached maximum lipase production, compared to others, under conditions of 32 °C and 2% of oil with a yield of 11,007 (µg mL-1). Penicillium sp. F04 achieved better results at 36 °C and 6% oil, although for Aspergillus niger F16 was at 36 °C and 10% oil and Aspergillus sp. F21 at 32 °C and 2% oil. These results show that microorganisms isolated from oily residues derived from environmental sanitation can be a promising alternative for the large-scale production of lipases.

Evaluation of Royal Sun Agaricus, Agaricus brasiliensis S. Wasser et al., aqueous extract in mice challenged with Salmonella enterica serovar Typhimurium.

This study investigated the effects of Agaricus brasiliensis S. Wasser et al. (=Agaricus blazei Murrill sensu Heinem.) aqueous extract on small intestinal sIgA levels, serum TNF-alpha, IFN-gamma and IL-10 levels, splenic index, bacterial translocation, and histology of small intestine, spleen, and liver from mice orally challenged with 10(6) CFU of Salmonella enterica serovar Typhimurium (SEST). Splenic index values as well as sIgA, TNF-alpha, IFN-gamma, and IL-10 levels were not affected by either A. brasiliensis aqueous extract treatment or by pathogenic challenge. Typical colonies of SEST were recovered from liver, spleen, and mesenteric lymph nodes of challenged animals, but there was no significant difference in this translocation between groups treated or not with A. brasiliensis aqueous extract. Translocation was confirmed by histopathological analysis in mice challenged with SEST, which showed small and diffuse foci of mixed inflammatory infiltrate in hepatic parenchyma. In conclusion, A. brasiliensis aqueous extract as tested in the present study did not influence any of the variables selected to evaluate in vivo its immunomodulatory effect suggested in the literature.

Chemical composition, extraction sources and action mechanisms of essential oils: Natural preservative and limitations of use in meat products.

The antimicrobial activity of essential oils (EO) is associated with the presence of secondary metabolites synthesized by plants. Its mechanism of action involves the interaction of its hydrophobic components with the lipids present in the cell membrane of microorganism, resulting in metabolic damages and cell death. Spoilage and pathogenic microorganisms are contaminants in meat and meat products with considerable impacts on food quality and safety. Research shows the potential of applying essential oils in the preservation of meat food systems as compounds of low toxicity, extracted from a natural source, and as an alternative to consumer demand for healthy foods with a more natural appeal. In addition, there is a great diversity of plants from which essential oils can be extracted, whose antimicrobial activity in vitro and in meat and meat products has been proven.

Óleo de aroeira vermelha e de suplementação de vitamina E em substituição aos promotores de crescimento sobre a microbiota intestinal de frangos de corte / Supplementation of pink pepper oil and vitamin E in replacement to antibiotic growth promoters in the broilers diet on response of ileal microbiota

Objetivou-se avaliar o uso de óleo de aroeira-vermelha (OAV) e da suplementação de vitamina E (VitE) sobre a microbiota intestinal de frangos de corte. Utilizou-se 400 pintos de corte distribuídos em um delineamento inteiramente casualizado, em grupos de cinco tratamentos e cinco repetições: dieta sem antimicrobiano; dieta com antimicrobiano; dieta com 0,4% OAV; dieta com 200mg de VitE kg-1; dieta com 0,4% OAV e 200mg de VitE kg-1. A adição de OAV reduziu o peso relativo dos intestinos (P<0,05). Verificou-se que o controle negativo teve a menor contagem de bactérias do gênero Lactobacillus spp. em contraste com os demais grupos (P<0,05). Observou-se que o uso de OAV com ou sem adição de VitE reduziu significativamente a contagem de bactérias do gênero Staphylococcus spp e E. coli, quando comparado com o grupo não tratado com o promotor de crescimento (P<0,05). Para os Staphylococcus spp coagulase-positivos, verificou-se que a concentração inibitória mínima foi de 14,72-117,75mg mL-1 para amostras isoladas de frangos de corte tratados com OAV + VitE, enquanto que para tratados com ou sem promotor de crescimento foi de 117,75 e de 29,44-235,5mg mL-1. Concluiu-se que a inclusão de OAV resultou em modulação da microbiota intestinal.

The aim was to evaluate the supplementation of pink pepper oil (PPO) and vitamin E on the intestinal microbiota of broiler chickens. A total of 400 day-old male chicks distributed in a randomized design in groups of five treatments and five replicates: diet without antimicrobial; diet with antimicrobial; diet with 0.4% PPO; diet with 200mg vitamin E kg-1; diet with 0.4% PPO and 200mg vitamin E kg-1 The supply of PPO in the diet reduced the relative weight of the intestines (P<0.05). It was verified that the negative control group had the lowest bacteria count of Lactobacillus in contrast to the other groups (P<0.05). It was also observed that the use of PPO with or without vitamin E supplementation significantly reduced the bacterial count of Staphylococcus spp and E. coli when compared with the untreated group with the growth promoter (P<0.05). For Staphylococcus spp. coagulase-positive, it was found that the minimum inhibitory concentration was 14,72-117,75mg mL-1 for isolates from broilers treated with PPO + vitamin E, while for treated with or without growth promoter was 117.75 and 29,44-235,5mg mL-1. It was concluded that the inclusion of PPO resulted in modulation of intestinal microbiota.