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This study aimed to assess the microbial diversity in Coffea canephora grown in four different environments of Espirito Santo state, Brazil. Coffee cherries of two different altitudes (300 and 600 m) and two terrain aspects (Southeast-facing and Northwest-facing slopes) were processed by the dry method. Samples were collected during the drying/fermentation process. Microorganisms were counted, isolated, and identified by MALDI-TOF, followed by sequencing of the ribosomal region. Sugars and organic acids were quantified by HPLC and volatile compounds of the roasted coffees were evaluated by GC–MS. Bacteria population presented a significant number of isolates as well as higher counts during the drying/fermentation process with respect to the population of yeasts. The principal genera of microorganisms found were Bacillus, Pichia, Candida, and Meyerozyma. Meyerozyma guilliermondii was the most frequent yeast in all environments. On the other hand, Pichia kluyveri was found only in coffee cherries from the 600 m altitude. The highest concentration of acetic and succinic acids observed was 6.06 mg/g and 0.84 mg/g, respectively. Sucrose concentrations ranged from 0.68 to 5.30 mg/g, fructose from 1.30 to 4.60 mg/g, and glucose from 0.24 to 1.25 mg/g. Thirty-six volatile compounds, belonging to the groups of pyrazines, alcohols, aldehydes, ketones, and furans were identified in roasted coffee, with differences between altitude and terrain aspects. Information about microbial diversity is crucial to better understand the coffee quality and distinct characteristics of coffee produced in different environments. [ABSTRACT FROM AUTHOR]

Hop is a plant with several biological properties. Many factors affect both the presence and concentration of hop compounds, such as cultivar, location and growth conditions. Recently, the interest of hop cultivation in Brazil has grown despite the tropical weather and it has been possible to obtain hop completely cultivated in Brazilian soil. This study analyzed the chemical composition and verified the antioxidant and antimicrobial activities of Brazilian hop hydroethanolic extracts in comparison to a commercially available hop cultivar. Brazilian hops were a good source of flavonoids (5.72–12.82 mg CE/g dw), and presented a high content of phenolic compounds, in particular the Canastra cultivar (35.1 mg GAE/g dw). The Brazilian cultivars showed interesting antioxidant and antimicrobial proprieties. Gram-positive and Gram-negative bacteria were susceptible to hop hydroethanolic extracts and Staphylococcus aureus was inhibited by the extracts of all cultivars. The extracts presented antifungal activity against Byssochlamys nivea and significant growth inhibition at the higher concentration tested (20 μl/ml). The hydroethanolic extracts exhibited a high content of α- and β-acids, mainly the Vitoria, Columbus and Canastra cultivars, reaching almost 60% (w/w). These characteristics evidenced the potential application of Brazilian hops as raw materials in both pharmaceutical and food industries. • Brazilian hops are a rich source of phenolic compounds, such as flavonoids. • Brazilian hop cultivars exhibited antioxidant and antimicrobial potentials. • Antimicrobial activity of hop extracts is more pronounced against S. aureus. • Hydroethanolic extracts of Brazilian hop cultivars are rich in α- and β-acids. [ABSTRACT FROM AUTHOR]

The current study aimed obtaining antimicrobial sachets that could be used as preservatives for foods. Basil (BEO) and Pimenta dioica (PDEO) essential oils (EOs) were analyzed by GC-FID and GC-MS and tested against the foodborne bacteria S. aureus, E. coli, L. monocytogenes, P. aeruginosa, S. Enteritidis, and the food-spoilage mold B. nivea. Then, inclusion complexes (ICs) with EOs and β-cyclodextrin (β-CD) were prepared as a strategy to reduce volatility and increase the release time of EOs. Eight ICs were prepared by kneading and freeze-drying methods, in two molar ratios, and have been characterized by complementary methods: FT-IR, thermal analysis (DSC and TG/DTG), powder XRD, and solid state 13 C NMR. In vitro antimicrobial activities of ICs, both dispersed in agar and loaded in sachets, have also been investigated. Complexation was confirmed for all samples. PDEO-based ICs prepared by kneading method, at both molar ratios, displayed better in vitro antimicrobial activity. The obtained results strongly suggest a potential application of these ICs as natural antimicrobials., (Copyright © 2019 Elsevier Ltd. All rights reserved.)