HPLC quantitative analysis of protocatechuic acid contents in 11 Phellinus mushroom species collected in Thailand

Abstract Phellinus mushrooms have been traditionally used for various medicinal purposes. Protocatechuic acid, which was previously reported to be a component in some Phellinus mushrooms, has some pharmacological effects. This study aimed to validate a HPLC method for the quantitative analysis of the protocatechuic acid contents in the extracts from different Phellinus mushroom species collected in Thailand. HPLC was carried out using a C18 column and the gradient mobile phases of 0.1% formic acid in water and 0.1% formic acid in acetonitrile. Method validation was performed to assure the linearity, accuracy, precision, limit of detection and limit of quantitation of the analytical method. The linearity range of protocatechuic acid was 1 - 10 µg/ml. The average recovery was 104.16%. The method was shown to be precise with the RSD of repeatability and intermediate precision at less than 3%. The protocatechuic contents in 11 Phellinus mushrooms were in the range of less than 0.0099 - 0.4121 %w/w of the extract. The developed HPLC method was reliable and suitable for the quantitative analysis of protocatechuic acid content in Phellinus mushrooms.

Antiherpetic Effects of Gynura procumbens.

The ethanol extract of Gynura procumbens showed virucidal and antireplicative actions against herpes simplex virus HSV-1 and HSV-2. It was further chromatographed on MCI gel CHP20P column giving the extract fractions F1 (water), F2 (water-methanol) F3 (methanol), and F4 (ethyl acetate). All but F1 had virucidal action against both viral types. We reported here the active compounds from F2 and F3. The antiherpetic compounds of F2 was a mixture of dicaffeoylquinic acids with virucidal and antireplicative actions against HSV-2 (IC50 96.0 and 61.0 µ g/mL, resp.) Virucidal compounds of F3 were a mixture of ß -sitosterol and stigmasterol (IC50 250.0 µ g/mL against HSV-1), a mixture of ß -sitosteryl and stigmasteryl glucosides (IC50 50.0 µ g/mL against HSV-2) and 1, 2-bis-dodecanoyl-3- α -D-glucopyranosyl-sn-glycerol (IC50 of 40.0 µ g/mL against HSV-2). Herbal products containing 1 and 2% of standardized ethanol extract were prepared. Double-blind randomized controlled clinical trial of the products was performed in patients with recurrent herpes labialis. Results showed that the number of patients, whose lesions healed within 7 days and the average healing time of both groups differed insignificantly. Viral culture on D7 indicated a decrease of infected patients from 48.7% to 7.69% in treated group whereas in placebo group the infected patients decreased from 31.25% to 20.00%. The viral reduction in treated group indicated the benefit of the product. Insignificant result might arise from a low number of participated patients and insufficient concentration of plant extract in herbal product.

Ameliorative Effects of Acanthopanax trifoliatus on Cognitive and Emotional Deficits in Olfactory Bulbectomized Mice: An Animal Model of Depression and Cognitive Deficits.

Acanthopanax trifoliatus is a plant that has been traditionally used in Thailand as a vegetable and a tonic. This study investigated effects of the aqueous extract of its leaves (ATL) on cognitive and emotional deficits using an olfactory bulbectomized mouse (OBX) model. OBX mice were treated daily with ATL (250 and 500 mg/kg, p.o.) 3 days after OBX. Antidementia drug tacrine (2.5 mg/kg/day) and antidepressant drug imipramine (10 mg/kg/day) were given i.p. as reference drugs. OBX significantly impaired cognitive behavior in a novel object recognition test and a modified Y-maze test and induced depression-like behavior in a tail suspension test. ATL and tacrine treatment attenuated OBX-induced cognitive deficits, whereas ATL and imipramine improved OBX-induced depression-like behavior. Neurochemical studies conducted after completing behavioral experiments demonstrated that OBX downregulated the expression levels of cholinergic marker genes encoding choline acetyltransferase and muscarinic M1 receptor in a manner reversed by ATL and tacrine. Moreover, ATL and tacrine administration inhibited the ex vivo activity of acetylcholinesterase in the brain. These findings suggest that ATL is beneficial for the treatment of cognitive and emotional deficits related to dementia with depressive symptoms and that the antidementia effect of ATL is mediated by normalizing the function of central cholinergic systems.

Determination of caffeoyl quinic acids and flavonoids in Acanthopanax trifoliatus leaves by HPLC.

Extracts from the leaves of Acanthopanax trifoliatus, harvested at different seasons, were quantitatively analyzed for phenolic contents using high performance liquid chromatographic (HPLC) methods. Samples collected in winter contained high amounts of the major active components, mono and di-caffeoylquinic acid derivatives and flavonoid glycosides. It was found that January and November were the preferred periods for collecting plant material containing high amounts of caffeoyl quinic acid and flavonoid constituents.

Antioxidant activity of Acanthopanax trifoliatus.

OBJECTIVE: The aim of this study was to investigate the antioxidant activity of extracts of various parts of Acanthopanax trifoliatus obtained by different extraction methods. The total phenolic and flavonoid contents of the extracts were also determined. MATERIALS AND METHODS: The leaves, stems, stem bark, roots and root bark of A. trifoliatus were extracted separately using decoction, maceration and refluxing methods. The extracts were analysed for free-radical-scavenging activity using the 1,1-diphenyl-2-picryl-hydrazyl scavenging assay and the thiobarbituric-acid-reactive substance method for the inhibition of lipid peroxidation of a rat brain homogenate. Total phenolic and total flavonoid contents of the extracts were measured by UV spectrophotometry. RESULTS: The leaf decoction extracts possessed a significantly stronger antioxidant activity as revealed by both methods. Total phenolic and flavonoid contents of the extracts ranged from 2.16 to 21.79 g% chlorogenic acid equivalent and from 0.37 to 9.61 g% rutin equivalent, respectively. Analysis of the leaf decoction extract, which exhibited the most potent antioxidant activity, by thin-layer chromatography revealed flavonoid and polyphenolic compounds corresponding to rutin and chlorogenic acid. CONCLUSION: The leaf aqueous extracts showed a high level of antioxidative activity and contained high levels of both phenolic and flavonoid compounds. The magnitude of antioxidant activity corresponded with the level of phenolic and flavonoid compounds.

Antibacterial properties of essential oils from Thai medicinal plants.

By using disc diffusion assay, the antimicrobial activity of 32 essential oil samples extracted from local plants or plants cultivated in Thailand was evaluated against zoonotic enteropathogens including Salmonella spp., Escherichai coli O157, Campylobacter jejunii and Clostridium perferingens which are important for broiler export. Out of the essential oil tested, only the essential oil of Zingiber cassumuna, Cinnamomum bejolghota, Mentha arvensis var. piperacens, Cymbopogon citratus and Ocimum basilicum var. citratum showed promising antibacterial activity against the bacteria tested.