RESUMOO mamão é fruta perecível, de vida útil pós-colheita curta. Novas tecnologias de conservação de produtos hortícolas com possibilidade de emprego em sistemas orgânicos têm sido desenvolvidas, a exemplo dos revestimentos comestíveis, que podem ser consumidos com o produto. Neste trabalho avaliou-se o amadurecimento de frutos de mamão Formosa Tainung 1 em temperatura ambiente, revestidos com película comestível à base de fécula de mandioca, que foi aplicada por meio de imersão dos frutos durante um minuto em suspensões de 1%, 2% e 3%. No dia da aplicação do tratamento e a cada quatro dias, durante 12 dias, os frutos foram avaliados quanto à perda de massa, cor da casca, firmeza da polpa, sólidos solúveis (SS), acidez titulável (AT) e relação SS/AT. O experimento foi conduzido em delineamento inteiramente casualizado, em esquema fatorial 4 x 4 (% de fécula na suspensão de tratamento x dias após o tratamento), com quatro repetições e um fruto por parcela. Os revestimentos comestíveis à base de fécula de mandioca a 1% e 3% prolongaram a vida útil pós-colheita de frutos de mamão Formosa Tainung 1 por quatro dias, sem afetarem a qualidade dos mesmos. Estes tratamentos retardaram o amadurecimento dos frutos, cujas alterações de cor da casca, firmeza da polpa, SS e AT foram significativamente mais lentas que os frutos não tratados. Termos para indexação:Carica papaya, atmosfera modificada, pós-colheita. ABSTRACTPapaya is a perishable fruit, of short shelf-life. New technologies of conservation of horticultural products with the possibility of being used in organic systems have been developed, such as the edible coatings that can be eaten with the product. In this work it was evaluated Tainung 1 Formosa type papaya ripening at room temperature and coated with edible cassava starch , which was applied by dipping the fruits during one minute in suspensions of 1%, 2% and 3%. In the day of treatment application and every four days, during 12 days, fruits were evaluated for mass loss, skin color, pulp firmness, total soluble solids (SS), total titratable acidity (AT) and ratio (SS/AT). The experiment was conducted at a completely randomized design, in a 4 x 4 factorial scheme (% starch in suspension x days after treatment), with four replications and one fruit per plot. The edible coatings of cassava starch at 1% and 3% extended the postharvest life of Formosa Tainung 1 papaya fruits for four days, without affecting their quality. These treatments delayed fruit ripening , whose skin color, pulp firmness, SS and AT changes were significantly slower than the ones of non-treated fruits.

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This study evaluated the production of cellulolytic enzymes by Trichoderma sp. IS-05 strain, isolated from sand dunes, according to its ability to grow on cellulose as carbon source. Wheat bran was tested as the carbon source and peptone tested as the nitrogen source. Different concentrations of carbon and nitrogen were tested using a factorial design to identify optimal cellulase activity production. The results showed that media containing wheat bran 4.0% (w/v) and peptone 0.25% (w/v) lead to the highest production, 564.0 U L−1 of cellulase, obtained after 2 days of fermentation. The pH and temperature profile showed optimal activity at pH 3.0 and 60°C. As for thermostability, the cellulase was most tolerant at 60°C, retaining more than 59.6% of maximal activity even after 4 hours of incubation. The combination of acid pH, high temperature tolerance, and production of cellulase from agro-industrial residues by Trichoderma sp. IS-05 offers possibilities condition for the biomass hydrolysis process to produce bioethanol.

ABSTRACT

Ganoderma lucidum is a medicinal mushroom with different forms of bioactivity that has been used in popular medicine for centuries. This study aimed to test the application of agricultural wastes (fruit shells, leaves, and bracts) from the endemic Brazilian palm tree Syagrus coronata (licuri) as substrates for the production of G. lucidum basidiomata and ligninolytic enzymes via solid-state fermentation. The best culture conditions were the same for all substrates (pH 6.5, carbon-to-nitrogen ratio = 40, and temperature 30°C) and were established from preliminary assays. The yield was not significantly different for bracts (33.53 g/kg) and leaves (37.48 g/kg), nor for the biological efficiency in these same substrates: bracts, 3.35%; leaves, 3.75%. The highest laccase (13.80 U/L) and manganese peroxidase (14.92 U/L) activities were achieved after 14 and 28 days of incubation, respectively, using bracts as the substrate. Licuri residues are then potential substrates to be used in the bioconversion process for mycelia, basidiomata, and ligninolytic enzyme production by G. lucidum.

This study aimed to evaluate the microbiological quality and the transmission of multidrug-resistant bacteria in different spices sold in town fairs (local food markets) in the municipalities of Recôncavo Baiano. Samples of black pepper, oregano, and cinnamon were collected over a period of six months and investigated for coliforms at 45 °C, Staphylococcus spp., Staphylococcus aureus, Bacillus spp., Bacillus cereus, Escherichia coli and Salmonella spp. The contamination in the black pepper samples (log 4.66 CFU g-1) was higher (P>0.05), than those of cinnamon (log 2.55 CFU g-1) and oregano (log 2.49 CFU g-1), particularly for B. cereus. E. coli (89%) and Salmonella spp. (67%) were isolated only from black pepper. B. cereus and S. aureus showed greater resistance to β-lactams (penicillin, oxacillin, and cefepime), with approximately 40% of the strains with a multiple antimicrobial resistance (MAR) index of 0.33 (i.e., resistant to three antimicrobials). E. coli was more resistant to ampicillin and Salmonella spp. to nalidixic acid, ampicillin, and ceftriaxone. Salmonella spp. had a MAR index ranging from 0.16 to 0.91 (i.e, resistant to up to 11 antimicrobials), and E. coli to up to 0.58 (i.e., resistant to 7 antimicrobials). In conclusion, the spices sold in the town fairs of Recôncavo Baiano are of low microbiological quality, with the presence of pathogens, of which some display high resistance to antimicrobials that are commonly used for treating foodborne illnesses.

An edible coating of sodium alginate incorporated with brown propolis (2.5%, 5%, 10%, and 15%) was applied to black pepper grains to improve microbiological quality over 30 days. Gas chromatography coupled with mass spectrometry identified 29 metabolites in the extract, mainly terpene compounds (51.74%), phenolic compounds (25.83%), and flavonoids (14.48%). Brown propolis showed greater antibacterial activity for Gram-positive bacteria (MIC from 0.1 to 0.5 mg.mL-1) and lower activity for Escherichiacoli (MIC 18 mg.mL-1). A 5% increase in propolis in the coating reduced Bacilluscereus counts by 7-fold, 9.4% for Staphylococcusaureus, and 5.4% for mesophilic bacteria. The edible sodium alginate coating containing brown propolis was effective in reducing microbes on black pepper, with a concentration of 15% propolis assuring the microbiological quality of the spice after 20 days.

The edible coating of chitosan with clove essential oil (CEO) was studied for its ability to reduce the microbial growth of pathogens (Escherichia coli O157:H7 CDCEDL933, Listeria monocytogenes CERELA, Salmonella Enteritidis ATCC13076, Staphylococcus aureus ATCC43300, and Pseudomonas aeruginosa ATCC27853) in Tambaqui fillets kept under refrigeration. In in vitro tests, chitosan showed higher antimicrobial activity against S. aureus and L. monocytogenes (MIC 0.5%), and CEO for L. monocytogenes (MIC 0.08%). Based on the antimicrobial activity of chitosan and CEO, Tambaqui fillets were subjected to different treatments, T1: chitosan 2%; T2: chitosan 2% + CEO 0.16%, and T3: chitosan 0.5% + CEO 0.08%, kept at 4 ºC for 72 h. The chitosan coating, incorporated with CEO, inhibited microorganisms in Tambaqui fillets and enhanced coating efficiency (p < 0.05). It was most effective against L. monocytogenes and S. aureus at the lowest CEO concentration (0.08%). Chitosan coating in combination with CEO enhanced the antimicrobial effect of pathogens on Tambaqui fillets, increased their shelf life under refrigeration, and was more effective against Gram-positive pathogens than Gram-negative pathogens.