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Erwinia carotovora is a major cause of potato tuber infection, which results in disastrous failures of this important food crop. There is currently no effective antibiotic treatment against E. carotovora. Recently we reported antibacterial assays of wound tissue extracts from four potato cultivars that exhibit a gradient of russeting character, finding the highest potency against this pathogen for a polar extract from the tissue formed immediately after wounding by an Atlantic cultivar. In the current investigation, antibacterial activity-guided fractions of this extract were analyzed by liquid chromatography-mass spectrometry (LC-MS) utilizing a quadrupole-time-of-flight (QTOF) mass spectrometer. The most active chemical compounds identified against E. carotovora were: 6-O-nonyl glucitol, Lyratol C, n-[2-(4-Hydroxyphenyl)] ethyldecanamide, α-chaconine and α-solanine. Interactions among the three compounds, ferulic acid, feruloyl putrescine, and α-chaconine, representing metabolite classes upregulated during initial stages of wound healing, were also evaluated, offering possible explanations for the burst in antibacterial activity after tuber wounding and a chemical rationale for the temporal resistance phenomenon., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2020 Elsevier Ltd. All rights reserved.)

The edible fruits of Myrciaria vexator McVaugh (Myrtaceae), from northern South America, are eaten in certain locales, either fresh or processed into jellies and drinks. Activity-guided fractionation of M. vexator resulted in identification of ellagic acid (1), cyanidin-3-O-glucoside (2), delphinidin-3-O-glucoside (3), 2-O-(3,4-dihydroxybenzoyl)-2,4,6-trihydroxyphenylacetic acid (4), and jaboticabin (5), and latter two compounds are being reported for the first time in this species. Ellagic acid was further examined, and found to inhibit cigarette smoke extract induced MMP-1 expression in vitro, and may be of significance in the treatment of chronic obstructive pulmonary (COPD). Other compounds identified for the first time from M. vexator include cyanidin-3-O-galactoside (6), cyanidin-3-O-arabinoside (7), cyanidin-3-O-rutionoside (8), petunidin (9), peonidin-3-O-galactoside (10) malvidin (11), hyperoside (12), querecetin-3-O-glucoside (13), and guajaverin (14), methyl protocatechuate (15), and protocatechuic acid (16)., (Copyright © 2012. Published by Elsevier Ltd.)

The plant Melissa officinalis L. has been used traditionally in the treatment of cognitive dysfunction. Based on its traditional medicinal use, it was assessed for its clinical efficacy in mild to moderate Alzheimer's patients. The plant was effective in the management of the disease. Therefore, based on this result, a similar plant extract was prepared in order to be screened for bioactivities which are relevant in Alzheimer's disease therapy. The extract was recently screened for antioxidant activity and it showed a wide range of antioxidant properties. Another important bioactivity is acetylcholinesterase inhibition, which the extract was screened for in the current investigation. The extract was capable of inhibiting the enzyme in a time and dose-dependent manner. Activity of the extract at 10 min was estimated as 1.72+/-0.16 microg equivalents of physostigmine/mg of the extract. Acetylcholinesterase inhibitory guided fractionation of the extract was then carried out. Most of the fractions showed inhibitory activity and were more potent than the extract. The contents of the most potent fraction were identified as cis- and trans-rosmarinic acid isomers and a rosmarinic acid derivative using LC-DAD-ESI-MS and NMR methods.