Sources for developing new medicinal products: biochemical investigations on alcoholic extracts obtained from aerial parts of some Romanian Amaryllidaceae species.

BACKGROUND: Although Galanthus nivalis L. (snowdrop) is known for the galanthamine content, used in the treatment of Alzheimer disease, the polyphenolic compounds of Amaryllidaceae species are less studied. Proper understanding of the polyphenolics in these extracts and of their antioxidant and antimicrobial properties may allow a reconsideration of their medicinal uses. METHODS: The polyphenolic content of four selected Amaryllidaceae species harvested from Romania (Galanthus nivalis L., Narcissus pseudonarcissus L., N. poeticus L. and Leucojum vernum L.) was determined by spectrophotometric methods; the identification of phenolic compounds was performed by a HPLC-MS method, in order to establish their polyphenolic fingerprints. For the evaluation of the antioxidant potential the following methods were employed: DPPH radical scavenging, FRAP, hemoglobin ascorbate peroxidase activity inhibition (HAPX), inhibition of lipid peroxidation catalyzed by cytochrome c, and electron paramagnetic resonance (EPR) spectroscopy assays. Antimicrobial activity was assessed using the disc diffusion method. RESULTS: Qualitative and quantitative analyses highlight important amount of polyphenols (over 15 mg/g); the main identified compounds are chlorogenic and p-coumaric acids in all species. Only G. nivalis shows antioxidant activity by all the used methods. G. nivalis and L. vernum strongly inhibits the growth of S. aureus, while N. poeticus shows a very good antifungal activity. CONCLUSIONS: The results of this study provide a new approach to the properties and therapeutic uses of some Romanian widespread Amaryllidaceae species that could be considered sources of developing new medicinal products with anti anti-staphylococcal and antifungal activity.

Origanum vulgare ssp. vulgare: Chemical Composition and Biological Studies.

The biological properties and main phenolic compounds of the O. vulgare L. ssp. vulgare extract are described in the present paper. The polyphenolic compounds were analyzed by chromatographic and spectrophotometric techniques. The antioxidant potential was evaluated using several methods: CUPRAC (cupric ion reducing antioxidant capacity), FRAP (ferric reducing ability of plasma), inhibition of lipid peroxidation catalyzed by cytochrome c, and superoxide (SO) scavenging assays. The antimicrobial activity of the oregano extract was evaluated by means of agar-well diffusion assay. The hepatoprotective effect of the O. vulgare extract on CCl4-induced hepatotoxicity was evaluated in rats. Liver injury was estimated by determination of alanine aminotransaminase (ALT), aspartate aminotransaminase (AST), gamma-glutamyl transferase GGT, total protein and albumin concentrations, glutathione peroxidase (GPx), catalase (CAT), superoxide dismutase (SOD) and malondialdehyde (MDA). These values were improved by the administration of oregano extract. A specific phenolic profile was evidenced by these data, with large amounts of rosmarinic and chlorogenic acids. The oregano extract showed very strong antioxidant activity in good agreement with the phenolic content. Antimicrobial activity was good, especially against Salmonella enteritidis and Aspergillus niger strains. The high hepatoprotective, antioxidant and antimicrobial activity, along with polyphenol-rich content, can support the use of O. vulgare in therapy. We also expect our results to open new research directions for designing important new drug products, using indigenous plant material.

Stachys Species: Comparative Evaluation of Phenolic Profile and Antimicrobial and Antioxidant Potential.

This study aimed to investigate the polyphenolic composition and antioxidant and antimicrobial potential of six Romanian Stachys species: S. officinalis, S. germanica, S. byzantina, S. sylvatica, S. palustris, and S. recta. The LC-MS/MS method was used to analyze the polyphenolic profile, while the phenolic contents were spectrophotometrically determined. The antioxidant activity was evaluated using the following methods: DPPH, FRAP, nitrite-induced autooxidation of hemoglobin, inhibition of cytochrome c-catalyzed lipid peroxidation, and electron paramagnetic resonance spectroscopy. The in vitro antimicrobial properties were assessed using agar-well diffusion, broth microdilution, and antibiofilm assays. Fifteen polyphenols were identified using LC-MS and chlorogenic acid was the major component in all the samples (1131.8-6761.4 µg/g). S. germanica, S. palustris, and S. byzantina extracts each displayed an intense antiradical action in relation to high contents of TPC (6.40 mg GAE/mL), flavonoids (3.90 mg RE/mL), and caffeic acid derivatives (0.89 mg CAE/mL). In vitro antimicrobial and antibiofilm properties were exhibited towards Candida albicans, Gram-positive and Gram-negative strains, with the most intense efficacy recorded for S. germanica and S. byzantina when tested against S. aureus. These results highlighted Stachys extracts as rich sources of bioactive compounds with promising antioxidant and antimicrobial efficacies and important perspectives for developing phytopharmaceuticals.

On the Apparent Redox Reactivity of "Oxygen-Enriched Water".

Molecular oxygen-enriched water (OxEW) is advocated in popular media as useful for various health issues, presumably due to involvement of a purported antioxidant activity and to such notions as "active oxygen." To our knowledge, there are no explicit reports in the scientific literature where such redox reactivity would be described and explained. Reported here are data showing that a commercial preparation of OxEW does display a measurable, albeit very small, antioxidant activity as monitored by reaction with a standard reagent, DPPH. Moreover, OxEW also displays an apparent pro-oxidant reactivity, against caffeic acid. This does not correlate with any UV-vis-detectable contents of chemical substances in the water, nor can it be explained by typical chemical impurities (e.g., hydrogen peroxide or molecular hydrogen) that would arise upon enrichment with molecular oxygen of pure water by the two most common procedures: purging with gaseous O2 or electrolysis. Instead, this apparent redox reactivity is revealed to be due to differences in pH and in chemical content - and the differences in turn are most likely due to the trace amounts of inorganic ions/elements in the OxEW; importantly, electrolysis, which is often employed as a means to generate O2 in OxEW preparation, is also found to enhance the redox effect of OxEW-like preparations. Thus, in line with expectations, the herein-reported data show that there are no long-lived reactive oxygen species, no activated oxygen, and no extra reducing agents in OxEW - but that an apparent weak redox reactivity can still be measured and assigned to simple side effects of the electrolysis procedure presumably performed in order to enrich the sample in oxygen.