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Peruvian Maca crops (Lepidium peruvianum), grown in two geographically-distant cultivation sites located at similar altitudes in the highlands of the Peruvian Andes (Junin at 4,200 m a.s.l. and Ancash 4,150 m a.s.l.), were used in the study. Four prime Maca phenotypes, distinguished by hypocotyl colours labelled as "Yellow", "Purple", "Red" and "Black" were selected to determine distribution in levels and corresponding ratios between individual Glucosinolates (Glucotropaeolin and m-methylglucotropaeolin) in an attempt to identify four Peruvian Maca phenotypes from analyses of powdered hypocotyls. There were highly significant differences (P<0.01) in hypocotyl weight/size of four Maca phenotypes harvested in two locations. The Junin crop represented a mostly "large" class (13.3 g) with "small" size hypocotyls (7.2 g), while a "small" class was predominant in Ancash (3.5 g). Powdered Yellow Maca showed significantly higher (P<0.001) microbial contamination than the other three, with Black Maca being the least infected. Only minor, statistically-confirmed differences were detected in nutritive characteristics between the four Maca phenotypes grown in Junin, however highly significant differences (P<0.01) in Glucosinolates existed between the Red and Black Maca grown in Junin and Ancash. Irrespective of the cultivation location, Red phenotypes showed the highest content of Total Glucosinolates, followed by Black and Purple, with the Yellow phenotype showing consistently lower levels. Highly significant P<0.01) differences determined in ratios of individual Glucosinolates between four Maca phenotypes grown in two locations, confirms an earlier assumption that sums of individual Glucosinolates, their ratios and profiles, may be feasible to explore in analytically identifying individual Maca phenotypes in pulverised marketed Maca products.

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Heptane (Hep), diethyl ether (Et2O), acetone (Me2CO) and methanolic (MeOH) extracts, as well as (-)-usnic acid and squamatic acid, were obtained from thallus of Cladonia uncialis (Cladoniaceae). The antimicrobial activities of these extracts, (-)-usnic acid and squamatic acid, were tested against reference strains: Staphylococcus aureus, Escherichia coli and Candida albicans. In addition, Me2CO extract was analysed against 10 strains of Methicillin-resistant S. aureus (MRSA) isolated from patients. All extracts exerted antibacterial activity against the reference strain S. aureus, comparably to chloramphenicol [minimum inhibitory concentration (MIC) = 5.0 μg/mL]. The Me2CO extract exhibited the strongest activity against S. aureus (MIC = 0.5 μg/mL), higher than (-)-usnic acid, whereas squamatic acid proved inactive. The Me2CO extract showed potent antimicrobial activity against MRSA (MIC 2.5-7.5 μg/mL). Also no activity of C. uncialis extracts against E. coli and C. albicans was observed.