The phenolic compounds from various extracts of jabuticaba skin powder (JSP) were characterized in this study, and the antibacterial activity assessed. The phenolic compounds were extracted from the JSP using four methods: a) acetone extraction -1 g JSP: 10 mL 70% acetone, resting for 2 hours; b) aqueous extract -1 g JSP: 15 mL water, under agitation; c) ethanolic extract -1 g JSP: 15 mL acidified ethanol, under agitation; and d) methanolic extract -1 g JSP: 50 mL 50% methanol, under reflux. The antibacterial activity was evaluated by the agar diffusion assay, using Escherichia coli ATCC 11229, Salmonella choleraesuis ATCC 6539, Pseudomonas aeruginosa ATCC 15442, Staphylococcus aureus ATCC 6538 and Listeria monocytogenes ATCC 19117. The ethanolic and methanolic extracts showed the highest levels of phenolic compounds, especially of cyanidin chloride, catechin and epicatechin. The extracts did not inhibit the growth of Escherichia coli and Salmonella choleraesuis, but inhibited 30% of the growth of Pseudomonas aeruginosa with an extract concentration of 250 µg mL -1 . Against Staphylococcus aureus and Listeria monocytogenes the highest inhibitory effect observed was 41.8% for the ethanolic extract, followed by 36% inhibition by the methanolic extract, thus revealing the potential of these extracts as possible alternatives for use in the food and/or pharmaceutical industries. ResumoNeste estudo, caracterizaram-se os compostos fenólicos e avaliou-se a atividade antibacteriana de extratos obtidos da farinha da casca de jabuticaba (FCJ). Os compostos fenólicos da FCJ foram extraídos de quatro formas: a) extrato acetônico -1 g FCJ: 10 mL acetona 70%, duas horas em repouso; b) extrato aquoso -1 g FCJ: 15 mL água, sob agitação; c) extrato etanólico -1 g FCJ: 15 mL etanol acidificado, sob agitação; e d) extrato metanólico -1 g FCJ: 50 mL metanol 50%, sob refluxo. A atividade antibacteriana foi avaliada pela técnica de difusão cavidade em Ágar, utilizando-se os microrganismos Escherichia coli ATCC 11229, Salmonella cholerasuis ATCC 6539, Pseudomonas aeruginosa ATCC 15442, Staphylococcus aureus ATCC 6538 e Listeria monocytogenes ATCC 19117. Os extratos etanólico e metanólico apresentaram os teores mais elevados de compostos fenólicos, sobretudo o cloreto de cianidina, catequina e epicatequina. Os extratos não inibiram o crescimento de Escherichia coli e Salmonella choleraesuis, mas inibiu em 30% o crescimento de Pseudomonas aeruginosa na concentração do extrato de 250 µg mL -1 . A maior inibição de crescimento registrada foi de 41,8% pelo extrato etanólico, seguida pela inibição de 36% pelo extrato metanólico, contra as bactérias Staphylococcus aureus e Listeria monocytogenes, revelando assim a potencialidade destes extratos como possível alternativa para utilização na indústria de alimentos e/ou farmacêutica. Cite as: Jabuticaba skin extracts: phenolic compounds and antibacterial activity. Braz.

Summary This study used the flour and anthocyanin extracts from jaboticaba skins as a dye in yogurt. Jaboticaba skins were lyophilised and ground. Yogurt that was made in the conventional fashion was treated with the addition of flour from jaboticaba skins in the concentrations of 0.1%, 0.5%, 1.0%, 1.5% and 2.0% or with the anthocyanin extract in the concentrations of 0.5%, 1.0%, 1.5%, 2.0% and 2.5%, with and without tannic acid; the yogurt samples were stored for 45 days. In general, the results of the acceptance test of the yogurt samples ranged between like slightly and like moderately. The highest scores received by the anthocyanin extract (like slightly) were obtained for the concentrations of 0.5–1.5%. The colour retention for all yogurt samples was above 70%. The average half‐life was greater than 2500 h, considered high. We conclude that the use of jaboticaba skins as additives to yogurt can be an alternative to add value to jaboticaba.

In this study, different phenolic extracts were obtained from the jaboticaba skin meal (JSM), whose phenolic compounds were characterized and their antibacterial activities were assessed. Moreover, the activity of lyophilized ethanolic extract of jaboticaba skin (EEJS) on wound healing was analyzed in rats. The JSM phenolic extracts were obtained in four ways: aqueous, methanolic, ethanolic, and acetone extracts. The phenolic compounds were characterized in these extracts by high-performance liquid chromatography, and their antibacterial activities were evaluated. The in vivo experiment was divided into four groups and received the following treatments: G1-silver sulfadiazine (positive control); G2-EEJS at 10%; G3-EEJS at 5%, and G4-EEJS at 2.5%. The aqueous extract did not inhibit the growing of any bacterium. The ethanolic, acetone, and methanolic extracts inhibited the growing of all bacteria tested at the concentrations of 1.25%, 2.50%, and 5.00%, respectively. The ethanolic extract was the one that showed the highest bacterial inhibition potential and the highest contents of phenolic compounds, especially of catechin, epicatechin gallate, and epicatechin. The G3 and G4 treatments presented faster wound healing compared to the G1 one, as it promoted a less intense inflammatory reaction and full closure of the wounds at an accelerated rate.

ABSTRACT. Jaboticaba is a fruit native to Brazil. Its skin represents up to 43% of the fruit and contains high levels of fiber, minerals and phenolic compounds. The use of the skin waste adds value to the fruit. However, one of the drawbacks of skin storage is the high water content, which requires drying processes to preserve the skin without leading to the loss of nutrients and antioxidants. The influence of different drying temperatures on the levels of nutrients and antioxidants was investigated. Jaboticaba (Plinia jaboticaba (Vell.) Berg, genotype Sabará) skins were lyophilized or dried at three temperatures (30, 45, and 60ºC, using food dryers). The skins were then ground, stored (protected from light) and subjected to analysis of proximate composition, vitamin C, phytate, polyphenols, anthocyanins and antioxidant activity. The drying process had little effect on the proximate composition of the flour, presenting significant difference only for crude protein, fiber and non-nitrogenous extract. The greatest preservation of chemical constituents occurs in the lyophilized jaboticaba skins. Among the drying temperatures tested, however, the skins dried at 45 and 60°C had more highly preserved nutritional substances and antioxidants.Keywords: Plinia jaboticaba, nutrients, bioactive compound.Influência da temperatura de secagem nos constituintes químicos de cascas de jabuticaba (Plinia Jaboticaba (Vell.) Berg) RESUMO. A jabuticaba é um fruto nativo do Brasil. Sua casca representa até 43% do fruto e contém altos níveis de fibras, minerais e compostos fenólicos, que são substâncias antioxidantes. O aproveitamento deste resíduo agregará valor ao fruto jabuticaba. Entretanto, um dos inconvenientes para o armazenamento das cascas é seu elevado teor de água, necessitando, portanto, de processos de secagem que viabilizem a sua conservação sem levar a perdas da qualidade nutritiva e antioxidante. Neste trabalho, estudou-se a influência de diferentes temperaturas de secagem sobre os teores dos nutrientes e compostos antioxidantes. As cascas de jabuticaba, Plinia jaboticaba (Vell.) Berg genótipo Sabará, foram secas por liofilização e em três temperaturas (30, 45 e 60ºC) em secadores de alimentos. Em seguida, foram moídas e armazenadas em frascos hermeticamente fechados, protegidos da luz e analisadas quanto à composição centesimal, vitamina C, fitato, polifenóis, antocianinas e atividade antioxidante. Verificou-se que o processo de secagem pouco afetou a composição centesimal das farinhas, havendo diferença significativa apenas para a proteína bruta, fibras alimentares e extrato não nitrogenado. Observou-se que as cascas liofilizadas apresentaram os teores mais elevados para todos os compostos bioativos. Entre as temperaturas testadas, no entanto, as peles secas a 45 e 60°C apresentaram alta conservação das substâncias nutritivas e antioxidantes.