RESUMO A resistência ao uso de drogas antifúngicas é uma grande preocupação para os cientistas, que buscam descobrir novos produtos para tratar infecções fúngicas. O objetivo deste estudo foi avaliar as atividades antioxidantes e antifúngicas de óleos essenciais e extratos de Plectranthus grandis e Plectranthus ornatus contra Trichophyton rubrum e Microsporum canis, fungos dermatófitos. Extratos foram obtidos a partir de folhas por maceração em etanol (96%) durante 7 dias. Os óleos essenciais foram obtidos por hidrodestilação e analisados por cromatografia gasosa/espectrometria de massa. Um total de 25 componentes foram identificados, como constituintes principais, os sesquiterpenos β-cariofileno, a-copaene, germacrene, β-cariofileno e óxido de cariofileno. As atividades antioxidantes foram avaliadas usando o teste de eliminação de DPPH e a ação antifúngica foi determinada pelo método de microdiluição de caldo. Os decoctos obtidos a partir da extração de óleo essencial apresentaram uma maior ação antioxidante quando comparados com os óleos essenciais, com valores de IC50 de 12,35 μg/mL e 15,69 μg/mL para P. ornatus e P. grandis, respectivamente. Os produtos naturais apresentaram atividade antifúngica significativa, com valores de MIC variando de 0,078 mg/mL a 0,31 mg/mL para todas as cepas. A atividade de sinergismo entre extratos de Plectranthus spp. e cetoconazol demonstrou uma ação de inibição do crescimento fúngico, quando da combinação com um fármaco antifúngico padrão, indicando seu potencial de uso em medicina veterinária preventiva para tratar dermatofitoses.

SUMMARY Resistance to use antifungal drugs is a great concern seeking for scientists to discover new products to treat fungal infections. The aim of this study was to evaluate the antioxidant and antifungal activities of essential oils and extracts of Plectranthus grandis and Plectranthus ornatus against Trichophyton rubrum and Microsporum canis dermatophytes strains. Extracts were obtained from leaves by maceration in ethanol (96%) during 7 days. The oils were obtained by hydrodistillation and analyzed by gas chromatography/mass spectrometry. A total of 25 components were identified, as major constituents the sesquiterpenes β-caryophyllene, α-copaene, germacrene, β-caryophyllene and caryophyllene oxide. Antioxidant activities were evaluated using DPPH scavenging assay and antifungal action was determined by the broth microdilution method. The decocts obtained from the extraction of essential oil presented a greater antioxidant action when compared with the essential oils, with IC50 values of 12.35 μg/mL and 15.69 μg/mL to P. ornatus and P. grandis, respectively. Natural products presented significant antifungal activity, with MIC values ranging from 0.078 mg/mL to 0.31 mg/mL for all strains. The synergistic activity between Plectranthus spp. extracts and ketoconazole demonstrated a fungal growth inhibitory action when combined with a standard antifungal drug, indicating its potential for use in preventive veterinary medicine to treat dermatophytoses.

This study aimed to characterize the chemical composition, determine the fatty acid profile, and quantify the bioactive compounds present in guava seed powder (Psidium guajava L.). The powder resulted from seeds obtained from guava pulp processing. The agro-industrial seeds from red guava cv. paluma were used, and they were donated by a frozen pulp fruit manufacturer. They contain varying amounts of macronutrients and micronutrients, with a high content of total dietary fiber (63.94 g/100g), protein (11.19 g/100g), iron (13.8 mg/100g), zinc (3.31 mg/100g), and reduced calorie content (182 kcal/100g). Their lipid profile showed a predominance of unsaturated fatty acids (87.06%), especially linoleic acid (n6) and oleic acid (n9). The powder obtained contained significant amounts of bioactive compounds such as ascorbic acid (87.44 mg/100g), total carotenoids (1.25 mg/100 g) and insoluble dietary fiber (63.55 g/100g). With regard to their microbiological quality, the samples were found suitable for consumption. Based on these results, it can be concluded that the powder produced has favorable attributes for industrial use, and that use of these seeds would be a viable alternative to prevent various diseases and malnutrition in our country and to reduce the environmental impact of agricultural waste.

Grape pomace (Vitis vinifera L.), Benitaka variety, grown in the semiarid region of Northeast Brazil was evaluated in relation to chemical composition, and content of minerals and functional properties. Its microbiological quality and toxic potential, using Artemia salina sp, were also investigated. The results showed that the flour obtained from these residues had below neutral pH (3.82), moisture (3.33g/100g), acidity of (0.64g of citric acid/100g), and ash (4.65 g/100g). The amount of total dietary fiber (46.17g/100g) stood out quantitatively compared to the content of carbohydrate (29.2g/100 g), protein (8.49g/100g), and lipids (8.16g/100g). The total energy was 224Kcal/100g. With regard to the compounds with functional properties, higher values of insoluble fiber 79% (36.4 g/100 g); vitamin C (26.25 mg of acid ascorbic/100g), and anthocyanins (131mg/100g) were found. The minerals iron, potassium, zinc, manganese, and calcium were present in higher concentrations. There were no significant copper values. The results showed that the grape residues are an important source of nutrients and compounds with functional properties suggesting that they can be incorporated as an ingredient in the diet and/or used as a dietary supplement aiming at health benefits. The residues did not show microbiological contamination and were considered nontoxic.