► Extracts from six Lippia species were analyzed by HPLC–PDA as a dereplication strategy. ► Lippia lupulina root extract was selected for fractionation based on PCA of HPLC–PDA data. ► Seven ...previously unreported compounds in this genus were isolated. ► Verbascoside and asebogenin showed best activities against Cryptococcus neoformans. ► A mechanism for flavanone glucosides interconvertions in acid media was proposed.
The Lippia genus is used in ethnobotany as food, beverages, seasoning and antiseptic remedies, among others. The chemical compositions of fifteen extracts of six Lippia species were investigated comparatively by HPLC–PDA. To avoid data replication of previous works on this genus, Lippia lupulina Cham. root ethanol extract was selected for isolation procedures based on Principal Component Analyses (PCA) of such data. Seven compounds previously unreported in this genus were isolated from this extract (a triterpene, two furanonaphtoquinones, a furanochromone, an isoflavone, a stilbene and an iridoid). The activities of extracts, fractions and pure compounds towards Candida albicans, Candida krusei, Candida parapsilosis and Cryptococcus neoformans were investigated. Two fractions from the extract of Lippia salviaefolia leaves showed marked inhibition of fungal growth, in addition to verbascoside and asebogenin, which showed MICs lower than 15.6μg/ml and may be promising leads for the development of new antifungal agents, especially against C. neoformans.
Phytochemical investigation from the stems of Alibertia edulis led to the isolation and identification of a new iridoid 6β‐hydroxy‐7‐epigardoside methyl ester (1) and a new saponin ...3β‐O‐α‐L‐rhamnopyranosyl‐(1→2)‐O‐β‐D‐glucopyranosyl‐(1→2)‐O‐β‐D‐glucopyranosyl‐28‐O‐β‐D‐glucopyranoside pomolate (2), along with three known compounds, shanzhiside methyl ester (3), ixoside (4), and 3,4,5‐trimethoxyphenyl 1‐O‐β‐D‐apiofuranosyl‐(1→6)‐O‐β‐D‐glucopyranoside (5). The structures of 1 and 2 were established on the basis of their spectroscopic data. Iridoid 1 and saponin 2 exhibited moderate inhibitory activities against Candida albicans and C. krusei in a dilution assay.
Proton magnetic resonance spectroscopy has proved to be useful for monitoring a number of metabolites in cerebral infarction. Combined magnetic resonance imaging and spectroscopy investigations were ...carried out in 14 patients with a recent ischaemic stroke (< 1 week); follow-up examinations were performed from day 28 to day 252 after stroke. The aim of this study was to assess the correlation between the changes of N-acetyl-aspartate, choline, creatine-phosphocreatine, lactate and clinical evolution measured by the Scandinavian Neurological Scale (SNS). Initially the lactate magnetic resonance signal was present in all patients and the other metabolite contents were significantly reduced (P < 0.001; unpaired t-test) as compared with those on the contralateral side. Spearman's rank correlation test showed a positive correlation between the initial reduction of N-acetyl-aspartate content and the SNS (P < 0.05), and between the final N-acetyl-aspartate content and the SNS (P < 0.001). Our results suggest that serial examination in stroke patients may provide further prognostic information and encourage controlled clinical studies.
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