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In an effort to find new antiviral agents from natural products, hot water extracts of eight traditionally used medicinal plants in Taiwan were investigated in vitro for their activities against adenoviruses (ADV) and herpes simplex viruses (HSV). Results demonstrated that all extracts exhibited antiviral activity with different degrees of potency. Only two extracts were active in suppressing both HSV and ADV infections. Three extracts inhibited only ADV infection whereas one extract blocked only HSV infection. These results suggested that the aforementioned medicinal plants merit further investigation.

The antioxidative activities of 12 medicinal plants and the compounds isolated from them were investigated using the thiocyanate method to evaluate inhibitory effects on lipid peroxidation in the linoleic acid system. The peroxide levels gradually increased during incubation in the presence of linoleic acid over 3 days, and most of the plants inhibited lipid peroxidation. In particular, of the plants tested, Cudrania tricuspidata, Zanthoxylum piperitum, Houttuynia cordata and Ulmus parvifolia reduced lipid peroxidation more effectively as lipid peroxidation progressed, resulting in inhibition of about 80% relative to the control value by the 3rd day of incubation. In addition, the polyphenols isolated from the plants also showed marked and dose-dependent inhibitory effects on lipid peroxidation. The compounds with the strongest activities were 3,4-dihydroxylbenzoic acid, quercetin, the quercetin glycosides quercetin-3-O-β-D-galactoside, quercetin-3-O-α-L-rhamnoside, quercetin-3-O-β-D-glucoside and quercetin-3-O-rutinose, catechin, gallic acid, methyl gallate and rosamultin isolated from Zanthoxylum piperitum, Houttuynia cordata, Rosa rugosa and Cedrela sinensis. Moreover, quercetin glycosides showed stronger activity than quercetin, suggesting that glycosylation increases the antioxidative activity of quercetin. Our results indicate that the medicinal plants and their polyphenols show promise as therapeutic agents for various disorders involving free radical reactions.

Traditional Chinese medicine (TCM) has been widely practiced and is considered as an alternative to conventional medicine. TCM herbal prescriptions contain a mixture of herbs that collectively exert therapeutic actions and modulating effects. Traditionally defined herbal properties, related to the pharmacodynamic, pharmacokinetic and toxicological, as well as physicochemical properties of their principal ingredients, have been used as the basis for formulating TCM multi-herb prescriptions. These properties are used in this work to develop a computer program for predicting whether a multi-herb recipe is a valid TCM prescription. This program is based on a statistical learning method, support vector machine (SVM), and it is trained by using 575 well-known TCM prescriptions and 1961 non-TCM recipes generated by random combination of TCM herbs. Testing results by using 72 well-known TCM prescriptions and 5039 non-TCM recipes showed that 73.6% of the TCM prescriptions and 99.9% of non-TCM recipes are correctly classified by this system. A further test by using 48 TCM prescriptions published in recent years found that 68.7% of these are correctly classified. These accuracies are comparable to those of SVM classification of other biological systems. Our study indicates the potential of SVM for facilitating the analysis of TCM prescriptions.

The increased life expectancy of the population has led to increasing incidences of cancer, chronic inflammatory and autoimmune diseases. Thus the continuous search for new drugs is necessary because ineffectiveness and adverse effects have been described for standard drugs. Essential oils are important sources of bioactive metabolites and several clinical trials have been developed using them. The Pterodon genus has been used in traditional medicine to treat rheumatic disorders, thus this work investigated the properties of essential oil from Pterodon polygalaeflorus fruits (EsOPpg) on acute inflammation and lymphocyte activation. The essential oil was obtained by hydrodistillation and its components were identified by GC/MS. The anti-inflammatory response was assessed using the air pouch model. Antinociceptive potential was evaluated using the writhing model. Lymphocyte phenotyping, cell cycle and apoptosis were analyzed by flow cytometry. EsOPpg promoted a reduction in leukocyte counts and protein concentration in the exudate, and reduced vasodilatation and inflammatory cell infiltrate in air pouch tissue. No antinociceptive effect was demonstrated for the doses tested. EsOPpg inhibited lymphocyte proliferation, arresting the cell cycle in G₁ phase, and induced apoptosis in these cells. EsOPpg downregulated both the total number of CD8⁺ T cells and the activated subpopulation (CD8⁺CD69⁺), while promoting upregulation of the total number of CD19⁺ and CD19⁺CD69⁺ B cells. In conclusion, Pterodon polygalaeflorus essential oil diminished the acute inflammatory response and inhibited lymphocyte proliferation, reducing neutrophil recruitment into the cavity and air pouch tissue and promoting distinct modulations of the activation level of each lymphocyte subpopulation.

Arbuscular mycorrhizal (AM) are symbiotic systems in nature and have great significance in promoting the growth and stress resistance of medicinal plants. During our literature search from the Chinese Scientific Information Database (Chinese National Knowledge Infrastructure, CNKI) we obtained 65 articles with "AM fungi" and "medicinal plant" as the key words, which indicates that in China, research efforts on these topics have been increasing. The main purposes of this review are to discuss the effects of mycorrhiza on the active ingredients of Chinese medicinal plants in comparison with results obtained in other plants in studies conducted by the international research community, and to introduce works published in Chinese journals to international colleagues.

Scientific Breakthrough – Starving Malaria Parasites Curbs the Disease

Back to Nature — Medicinal Plants of Nepal Point New Direction to Drug Discovery

Many plants of genus Prosopis (Leguminosae) are known to be of medicinal value because of increasing bacterial resistance against antibiotics and reported side effects of drugs ,researchers are trying to find new drugs and its natural source. In this study antibacterial activity of Prosopis juliflora was tested in -vitro against six gram positive and negative bacteria by paper disk diffusion and well methods.

In this purpose the methanolic extract at different concentrations (0.05, 0.1, 0.2, 0.3, 0.4 mg ml ⁻¹) against Staphylococus aureus, Micrococcus loteus, Bacillus cereus, Shigella sonee, Pseudomonas aeruginosa and Escherichia coli were tested.

Comparison were made with Amoxicillin and Methicin.Results showed that Pseudomonas aureginosa had the maximum resistant and Micrococcus luteus had the less resistant against this extract.

Further work needs to be done in this extract including fractionation to isolate active constituents and subsequent pharmacological evaluation.