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Background: Macamides with a benzylalkylamide nucleus are characteristic and major bioactive compounds in the functional food maca (Lepidium meyenii Walp). The aim of this study was to explore variations in macamide content among maca from China and Peru. Twenty-seven batches of maca hypocotyls with different phenotypes, sampled from different geographical origins, were extracted and profiled by liquid chromatography with ultraviolet detection/tandem mass spectrometry (LC-UV/MS/MS)., Results: Twelve macamides were identified by MS operated in multiple scanning modes. Similarity analysis showed that maca samples differed significantly in their macamide fingerprinting. Partial least squares discriminant analysis (PLS-DA) was used to differentiate samples according to their geographical origin and to identify the most relevant variables in the classification model. The prediction accuracy for raw maca was 91% and five macamides were selected and considered as chemical markers for sample classification., Conclusion: When combined with a PLS-DA model, characteristic fingerprinting based on macamides could be recommended for labelling for the authentication of maca from different geographical origins. The results provided potential evidence for the relationships between environmental or other factors and distribution of macamides. © 2016 Society of Chemical Industry., (© 2016 Society of Chemical Industry.)

A moderately halophilic actinomycete strain, designated YIM 90010T, was isolated from a soil sample collected from a hypersaline habitat in Xinjiang Province, China, and then investigated using a polyphasic taxonomic approach. The strain produced abundant aerial mycelia and fragmented substrate mycelia on most media tested; the optimum NaCl concentration for growth was 10 % (w/v) and the optimum growth temperature and pH were 28 degrees C and 7.2, respectively. Chemotaxonomically and phylogenetically, the strain was related to members of the genus Nocardiopsis. The isolate contained chemotaxonomic markers that were diagnostic for the genus Nocardiopsis, i.e. meso-diaminopimelic acid, no diagnostic sugars, and MK-10(H6), MK-10(H8) and MK-12 as the predominant menaquinones. The major fatty acids were iso- and anteiso-branched acids combined with tuberculostearic acid (Me C(18 : 0)), straight-chain saturated fatty acids and unsaturated fatty acids. The G + C content was 73.1 mol%. Phylogenetic analysis confirmed that strain YIM 90010T was a member of the genus Nocardiopsis and most closely related to Nocardiopsis kunsanensis (97.6 % similarity) and Nocardiopsis xinjiangensis (98.1 % similarity). It can be differentiated from these species by using phenotypic characteristics, phylogenetic analysis and DNA-DNA hybridization results. On the basis of the polyphasic evidence, a novel species, Nocardiopsis salina sp. nov., is proposed. The type strain of the species is YIM 90010T (= KCTC 19003T = CCTCC AA 204009T).