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Homocysteine (Hcy), a sulfur amino acid, is the only direct precursor for L-methionine synthesis through a reaction that requires vitamin B₁₂, representing a connection with "one-carbon" units metabolism. Hcy catabolism requires vitamin B₆ and as a consequence, alteration in folic acid and B vitamins status impairs Hcy biotransformation. Numerous studies have indicated that Hcy is an independent risk factor for cardio- and cerebrovascular diseases. In the last decade, several clinical trials have investigated the possible correlation between the use of folic acid and vitamins B₆ and B₁₂ for lowering Hcy plasma concentration and the reduced risk of stroke or its recurrence. This review is aimed to present some aspects of Hcy biochemistry, as well as the mechanisms through which it exerts the toxic effects on the vascular endothelium. We also discuss the results of some of the clinical trials developed to investigate the beneficial effects of vitamin therapy in the prevention and management of stroke.

The essential oil extracted by hydrodistillation from Romanian Artemisia annua aerial parts was characterized by GC/MS analysis, which allowed the identification of 94.64% of the total oil composition. The main components were camphor (17.74%), α-pinene (9.66%), germacrene D (7.55%), 1,8-cineole (7.24%), trans-β-caryophyllene (7.02%), and artemisia ketone (6.26%). The antimicrobial activity of this essential oil was evaluated by determining the following parameters: minimal inhibitory concentration (MIC), minimal bactericidal concentration (MBC), minimal fungicidal concentration (MFC), and minimal biofilm eradication concentration (MBEC). Moreover, the soluble virulence factors were quantified with different biochemical substrates incorporated in the culture media. The reference and resistant, clinical strains proved to be susceptible to the A. annua oil, with MICs ranging from 0.51 to 16.33 mg/ml. The tested essential oil also showed good antibiofilm activity, inhibiting both the initial stage of the microbial cell adhesion to the inert substratum and the preformed mature biofilm. When used at subinhibitory concentrations, the essential oil proved to inhibit the phenotypic expression of five soluble virulence factors (hemolysins, gelatinase, DNase, lipases, and lecithinases). Briefly, the present results showed that the A. annua essential oil contained antimicrobial compounds with selective activity on Gram-positive and Gram-negative bacterial strains as well as on yeast strains and which also interfere with the expression of cell-associated and soluble virulence factors.

Cerebrovascular accidents are currently the second major cause of death and the third leading cause of disability in the world, according to the World Health Organization (WHO), which has provided protocols for stroke prevention. Although there is a multitude of studies on the health benefits associated with anthocyanin (ACN) consumption, there is no a rigorous systematization of the data linking dietary ACN with stroke prevention. This review is intended to present data from epidemiological, in vitro, in vivo, and clinical studies dealing with the stroke related to ACN-rich diets or ACN supplements, along with possible mechanisms of action revealed by pharmacokinetic studies, including ACN passage through the blood-brain barrier (BBB).

This study was aimed at investigating the antimicrobial and antioxidant activity of ethanol extracts obtained from the leaves, seeds and sheaths of Robinia pseudoacacia. Total phenolic content (TPC, Folin-Ciocalteu method), antioxidant activity (trolox equivalent antioxidant capacity (TEAC) assay) and antimicrobial activity (agar disk diffusion method and broth dilution method) of the vegetative and reproductive organs of R. pseudoacacia were determined. The highest content of polyphenols (expressed as gallic acid equivalents, GAE) was found in the extract of R. pseudoacacia leaves (266.7 μg GAE mL -1 extract) followed by the extract of the seeds (232.2 μg GAE mL -1 extract). HPLC analysis showed the presence of catechin (0.925 μg mL -1 ), rutin (0.831 μg mL -1 ), resveratrol (0.664 μg mL -1 ) and quercetin (0.456 μg mL -1 ) in the leaf extract, and catechin (0.127 μg mL -1 ), epicatechin (0.239 μg mL -1 ) and rutin (0.231 μg mL -1 ) in the seed extract. The results showed that the studied extracts exhibited a selective antimicrobial effect directed against Gram-positive (Staphylococcus aureus and Bacillus subtilis) and Gram-negative (Pseudomonas aeruginosa, Klebsiella pneumoniae and Escherichia coli) bacterial strains. The combination leaf extract/antibiotic had the highest synergistic effect when compared to combinations with seed and sheath extracts. The same extract with penicillin G, kanamycin and rifampin had highest synergetic effect against methicillinresistant S. aureus strain (MRSA), a strain that has gained great interest of microbiologists within the past decades. The chemical characterization of ethanol extracts from the vegetative and reproductive organs of R. pseudoacacia, the synergistic effects of certain antibiotics and acacia extracts and the potential to increase the antimicrobial activity of some commercial antibiotics against MRSA were investigated for the first time.

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The hydrodistilled essential oils and volatile compounds (by static headspaces technique) of Mentha piperita L. and M. spicata L. were characterized by GC-MS. Headspace analysis of Mentha piperita revealed the existence of menthone (25.4%), 1,8-cineole (17.7%) and menthol (12.1%) as the main components, while the essential oil contained high amounts of menthol (46.8%) and menthone (25.6%). By contrast, headspace analysis of M. spicata showed a high content of limonene (37.0%) together with carvone (13.0%), -pinene (10.4%) and -pinene (9.8%), while the essential oil was reach in carvone (51.7%), dihydrocarveol (11.5%) and cis-dihydrocarvone (9.1%). Eleven samples of peppermint tea available on the Romanian market were analysed by headspace GC-MS. The volatile profile of the tea samples was compared with that of Mentha piperita L. and certain differences were emphasized and discussed.

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