Green coffee seed residue: A sustainable source of antioxidant compounds.

Oil extraction from green coffee seeds generates residual mass that is discarded by agribusiness and has not been previously studied. Bioactive secondary metabolites in coffee include antioxidant phenolic compounds, such as chlorogenic acids. Coffee seeds also contain caffeine, a pharmaceutically important methylxanthine. Here, we report the chemical profile, antioxidant activity, and cytotoxicity of hydroethanolic extracts of green Coffea arabica L. seed residue. The extracts of the green seeds and the residue have similar chemical profiles, containing the phenolic compounds chlorogenic acid and caffeine. Five monoacyl and three diacyl esters of trans-cinnamic acids and quinic acid were identified by ultra-performance liquid chromatography/electrospray ionization-quadruple time of flight mass spectrometry. The residue extract showed antioxidant potential in DPPH, ABTS, and pyranine assays and low cytotoxicity. Thus, coffee oil residue has great potential for use as a raw material in dietary supplements, cosmetic and pharmaceutical products, or as a source of bioactive compounds.

Production of ligninolytic enzymes and some diffusible antifungal compounds by white-rot fungi using potato solid wastes as the sole nutrient source.

AIMS: The aim of this study was to evaluate the synthesis of ligninolytic enzymes and some diffusible antifungal compounds by white-rot fungi (WRF) using peels or discarded potato as the sole nutrient source. METHODS AND RESULTS: The strain Trametes hirsuta Ru-513 highlighted for its laccase activity (595 ± 33 U l-1 ), which is able to decolourize 87% of an anthraquinone dye using potato peels as the sole nutritional support. A native polyacrylamide gel of laccase proteins showed the presence of two isoenzymes, corresponding to proteins of 56 and 67 kDa, which were detected by SDS-PAGE. The antifungal activity of ethyl acetate extracts was evaluated by the agar diffusion method, where Anthracophyllum discolor Sp4 and Inonotus sp. Sp2 showed the highest inhibition zones of Mucor miehei. The fungal extracts also inhibited Fusarium oxysporum and Botrytis cinerea growth, with inhibition zones of up to 18 mm. The extract with the highest antifungal activity, from A. discolor Sp4 grown in discarded potato medium, was analysed using a gas chromatograph coupled to a mass spectrometer. Among the identified compounds, chlorinated aromatic compounds and veratryl alcohol were the most abundant compounds. CONCLUSIONS: The results revealed the relevance of potato waste valorization for the sustainable production of ligninolytic enzymes and antifungal compounds. SIGNIFICANCE AND IMPACT OF THE STUDY: This study reports the synthesis of ligninolytic enzymes and diffusible antifungal compounds by WRF using potato wastes as the sole nutrient source and suggests a relationship between the enzymatic activity and the synthesis of antifungal compounds. These compounds and the synthesis of halogen compounds by WRF using agro-industrial wastes have been poorly studied before.

Pothomorphe umbellata: antifungal activity against strains of Trichophyton rubrum.

Trichophyton rubrum is a dermatophyte, which can cause infections in human skin, hair and nail. Pothomorphe umbellata (L.) Miq. (Piperaceae) is a native Brazilian plant, in which phytochemical studies have demonstrated the presence of steroids, 4-nerolidylcatechol, sesquiterpenes and essential oils. The objective of this study was to analyze the in vitro activity of extracts and fractions of P. umbellata on resistant strains of T. rubrum. The microdilution plate method was utilized to test Tr1, H6 and ΔTruMDR2 strains of T. rubrum; ΔTruMDR2 strain was obtained from H6 by TruMDR2 gene rupture, which is involved in multiple drugs resistance. The highest antifungal activity to all strains was observed for dichloromethane and hexane fractions of the 70% ethanolic extract which showed minimal inhibitory concentration (MIC) and minimal fungicide concentration (MFC) of 78.13 µg/mL. This antifungal activity was also obtained by 70% ethanolic extract, which presented MIC and MFC of 78.13 µg/mL to ΔTruMDR2, whereas the MIC values for Tr1 and H6 were 78.13 and 156.25 µg/mL, respectively. Our results suggest the potential for future development of new antifungal drugs from P. umbellata, especially to strains presenting multiple resistance.