Anticomplementary activity of stilbenes from medicinal plants

The anticomplementary activity of stilbenes from medicinal plants in Korea was investigatedin vitro. 3,5-Dihydroxy-4′-methoxystilbene (3) was most potent with IC₅₀ value of 1.5×10⁻⁴ M followed by rhapontigenin (4), oxyresverastrol (2), 2,3,4′,5-tetrahydroxystilbene-2-O-β-glucoside (9), rhaponticin (8), resverastrol (1), and piceid (7). The activity was found to be increased by a methylation on a hydroxy group of C-4′ of1, but decreased by further methylation on hydroxy groups of C-3 and C-5 and glucosylation on any hydroxy group of1. Addition of hydroxy group on C-2′ of1 or C-3′ of3 was little affected on the anticomplementary activity but the activity was increased byO-glucosylation on C-2 of1.     

Hypoglycemic activity of medicinal plants

The hypoglycemic activity of water extracts of fifty six medicinal plants were evaluated in the streptozotocin-induced diabetic mice. Twelve medicinal plants have significantly antidiabetic activity; Mori Radicis Cortex, Kwang Fang Chi Radix, Paeoniae Radix, Eugeniae Flos, Atractylodis Rhizoma, Ophiopogonis Tuber, Rosae multiflorae Fructus, Glycyrrhizae Radix, Tetrapanacis Medulla, Bigno, Forsythiae Fructus and Sophorae Radix.     

In vitro cytotoxicity and antioxidant activities of five medicinal plants of Malvaceae family from Cameroon

The potential antiproliferative and antioxidant activities of extracts from five medicinal plants from Cameroon were evaluated in vitro on HepG-2 cells. The results showed the significant decrease of the viability of the cells in a concentration-dependent manner. According to the IC(50) obtained, the extracts of S. acuta (461.53±0.23) and U. lobata (454.93±0.12) showed significant antiproliferative activity. At fixed concentration (250μgmL(-1)), extracts demonstrated higher antiproliferative activity (67.05%; 65.42%), (52.62%; 56.64%) and (32.98%; 36.85%) respectively during 24, 48 and 72h. Extracts of S. cordifolia and V. album demonstrated significant antiproliferative property after 48h while S. rhombifolia exhibited weak cytotoxicity. The results of the antioxidant properties showed that theses extracts induced significantly increase of SOD, CAT and GsT activity after 48h. Taken together, the results extracts showed that of S. acuta and U. lobata may be a promising alternative to synthetic substances as natural compound with high antiproliferative and antioxidant activities.     

Antiproliferative activity of Vietnamese medicinal plants

Methanol, methanol-water (1:1) and water extracts were prepared from seventy-seven Vietnamese medicinal plants and tested for their antiproliferative activities against human HT-1080 fibrosarcoma cells. Among them, fifteen extracts including seven methanol extracts of Caesalpinia sappan, Catharanthus roseus, Coscinium fenestratum, Eurycoma longifolia, Hydnophytum formicarum and Streptocaulon juventas (collected at two areas), six methanol-water (1:1) extracts of Cae. sappan, Cat. roseus, Co. fenestratum, H. formicarum and S. juventas (at two areas), and two water extracts of Cae. sappan and S. juventas exhibited antiproliferative activities in a concentration-dependent manner. Their antiproliferative activities against human cervix HeLa adenocarcinoma, human lung A549 adenocarcinoma, murine colon 26-L5 carcinoma, murine Lewis lung carcinoma (LLC) and murine B16-BL6 melanoma cells were then examined. Co. fenestratum showed selective activity against lung carcinoma and/or lung metastatic cell lines, A549, LLC and B16-BL6, while H. formicarum and S. juventas showed selective activity against human tumor cell lines, HeLa and A549. Characteristic morphological change and DNA fragmentation indicated the antiproliferative activity to be due to the induction of apoptosis.     

Antimalarial activity of Tanzanian medicinal plants

Tanzanian medicinal plants were extracted and tested for in vitro antimalarial activity, using the multidrug resistant K1 strain of Plasmodium falciparum. Of 49 plants investigated, extracts of three plants were found to have an IC50 between 5-10 micrograms/ml, extracts of 18 other plants showed an IC50 between 10 and 50 micrograms/ml, all others were less active. The three most active extracts were obtained from the tubers of Cyperus rotundus L. (Cyperaceae), the rootbark of Hoslundia opposita Vahl. (Labiatae), and the rootbark of Lantana camara L. (Verbenaceae).     

Anti-HIV activity of Indian medicinal plants

Acquired immunodeficiency syndrome patients face great socio-economic difficulties in obtaining treatment. There is an urgent need for new, safe, and cheap anti-HIV agents. Traditional medicinal plants are a valuable source of novel anti-HIV agents and may offer alternatives to expensive medicines in future. Various medicinal plants or plant-derived natural products have shown strong anti-HIV activity and are under various stages of clinical development in different parts of the world. The present study was directed towards assessment of anti-HIV activity of various extracts prepared from Indian medicinal plants. The plants were chosen on the basis of similarity of chemical constituents with reported anti-HIV compounds or on the basis of their traditional usage as immunomodulators. Different extracts were prepared by Soxhlet extraction and liquid-liquid partitioning. Ninety-two extracts were prepared from 23 plants. Anti-HIV activity was measured in a human CD4+ T-cell line, CEM-GFP cells infected with HIV-1NL4.3. Nine extracts of 8 different plants significantly reduced viral production in CEM-GFP cells infected with HIV-1NL4.3. Aegle marmelos, Argemone mexicana, Asparagus racemosus, Coleus forskohlii, and Rubia cordifolia demonstrated promising anti-HIV potential and were investigated for their active principles.     

Antibacterial activity of some Indian medicinal plants

Aqueous extracts of ten medicinal plants were examined for their antibacterial potential against some reference strains of human pathogenic bacteria. Anethum graveolens, Elettaria cardamomum, Foeniculum vulgare, Trachyspermum ammi and Viola odorata were found to be better/equally effective compared to standard antibiotics. V. odorata was the most effective antibacterial with minimum inhibitory concentration values ranging from 1 to 2%. The results provide a scientific basis for the centuries-old usage of aqueous extracts of these medicinal plants.     

Anti-angiogenic activity of resveratrol, a natural compound from medicinal plants

Resveratrol (3,4',5-trihydroxy-trans-stilbene), a naturally occurring phytoalexin found in grapes and wine, possesses cancer-preventive activity. Angiogenesis is a crucial step in the growth and metastasis of cancers. We have investigated the effect of resveratrol on angiogenesis in vitro and ex vivo, and found that resveratrol directly inhibited human umbilical vein endothelial cell growth and decreased the gelatinolytic activities of matrix metalloproteinase-2. Tube formation was inhibited by treatment with resveratrol after plating endothelial cells on Matrigel. Resveratrol treatment also inhibited endothelial cell attachment to basement membrane components fibronectin and laminin, and displays similar behavior on cell chemotaxis. In addition, resveratrol has been found to be an angiogenesis inhibitor in the rat aorta matrix culture model. Therefore, inhibition of angiogenesis associated with cancer may be a novel mechanism for the anticancer activity of resveratrol.     

Antidiabetic agents from medicinal plants

Currently available therapeutic options for non-insulin-dependent diabetes mellitus, such as dietary modification, oral hypoglycemics, and insulin, have limitations of their own. Many natural products and herbal medicines have been recommended for the treatment of diabetes. The present paper reviews medicinal plants that have shown experimental or clinical antidiabetic activity and that have been used in traditional systems of medicine; the review also covers natural products (active natural components and crude extracts) isolated from the medicinal plants and reported during 2001 to 2005. Many kinds of natural products, such as terpenoids, alkaloids, flavonoids, phenolics, and some others, have shown antidiabetic potential. Particularly, schulzeines A, B, and C, radicamines A and B, 2,5-imino-1,2,5-trideoxy-L-glucitol, beta-homofuconojirimycin, myrciacitrin IV, dehydrotrametenolic acid, corosolic acid (Glucosol), 4-(alpha-rhamnopyranosyl)ellagic acid, and 1,2,3,4,6-pentagalloylglucose have shown significant antidiabetic activities. Among active medicinal herbs, Momordica charantia L. (Cucurbitaceae), Pterocarpus marsupium Roxb. (Leguminoceae), and Trigonella foenum graecum L. (Leguminosae) have been reported as beneficial for treatment of type 2 diabetes.     

Antitumor triterpenes from medicinal plants

Thirteen kinds of naturally occurring or derivatised triterpenes, reported to have an antitumoral property, were reinvestigated on the basis of their direct cytotoxicity or the inhibitory activity on cell growth against five kinds of cultured human tumor cells,i. e., A-549, SK-OV-3, SK-MEL-2, XF498 and HCT15,in vitro. Ursonic acidIII, betulinic acidVIII, betulonic acidX and glycyrrhetinic acidXI were exhibited a marked inhibition on cell growth.     

Anti-Helicobactor pylori activity of some Jordanian medicinal plants

Context: Natural flora are considered a major source of new agents for the treatment of Helicobactor pylori. The plants used in this study were selected based on previous traditional use.

Objective: In this study, we evaluated the effect of extracts of 16 medicinal plants grown in Jordan against clinical isolates of H. pylori.

Materials and methods: Tested plant extracts included Aloysia triphylla (L'Her.) Britton (Verbenaceae), Anethum graveolens L. (Apiaceae), Artemisia inculata Delile (Asteraceae), Capparis spinosa L. (Capparaceae), Crataegus aronia (L.) Bosc ex. DC. (Rosaceae), Inula viscose (L.) Ait (Asteraceae), Lavandula officinalis Chaix. (Lamiaceae), Lepidium sativum L. (Cruciferae), Origanum syriaca L. (Lamiaceae), Paronychia argentea Lam. (Caryophyllaceae), Passiflora incarnate L. (Passifloraceae), Psidium guajava L. (Myrtaceae), Sarcopoterium spinosum (L.) Spach (Rosaceae), Sesamum indicum L. (Pedaliaceae), Urtica urens L. (Urticaceae) and Varthemia iphionoids Boiss (Asteraceae). Clinical isolates of H. pylori were tested in vitro for susceptibility to each of the above plant crude extracts using disk diffusion method, and the MIC value was determined for each plant extract using the serial dilution method.

Results: Results showed that ethanol extracts of most medicinal plants exerted cytotoxiciy against H. pylori isolates. Among the tested plant extracts, A. triphylla (MIC: 90?µg/mL, MBC: 125?µg/mL) and I. viscosa (MIC: 83?µg/mL, MBC: 104?µg/mL) showed the strongest activity against both isolates of H. pylori.

Discussion and conclusion: Jordanian medicinal plants might be valuable sources of starting materials for the synthesis of new antibacterial agents against H. pylori.     

Xanthine oxidase inhibitory activity of Vietnamese medicinal plants

Among 288 extracts, prepared from 96 medicinal plants used in Vietnamese traditional medicine to treat gout and related symptoms, 188 demonstrated xanthine oxidase (XO) inhibitory activity at 100 microg/ml, with 46 having greater than 50% inhibition. At 50 microg/ml, 168 of the extracts were active, with 21 possessing more than 50% inhibition. At 25 microg/ml, 146 extracts exhibited inhibitory activity, with 8 showing over 50% inhibition, while 126 extracts presented activity at 10 microg/ml, with 2 having greater than 50% inhibition. The MeOH extracts of Artemisia vulgaris, Caesalpinia sappan (collected at the Seven-Mountain area), Blumea balsamifera (collected in Lam Dong province), Chrysanthemum sinense and MeOH-H(2)O extract of Tetracera scandens (Khanh Hoa province) exhibited strong XO inhibitory activity with IC(50) values less than 20 microg/ml. The most active extract was the MeOH extract of the flower of C. sinense with an IC(50) value of 5.1 microg/ml. Activity-guided fractionation of the MeOH extract led to the isolation of caffeic acid (1), luteolin (2), eriodictyol (3), and 1,5-di-O-caffeoylquinic acid (4). All these compounds showed significant XO inhibitory activity in a concentration-dependent manner, and the activity of 2 was more potent (IC(50) 1.3 microM) than the clinically used drug, allopurinol (IC(50) 2.5 microM).     

Hypoglycaemic activity of some medicinal plants in Sri-Lanka

1. Investigations were carried out to determine whether aqueous extracts of Osbeckia octandra, Artocarpus heterophyllus and Bambusa vulgaris truly possess oral hypoglycaemic activity. 2. All three plant extracts significantly lowered the fasting blood glucose level and markedly improved glucose tolerance in Sprague-Dawley rats. 3. A maximum hypoglycaemic activity was observed at +3 hr with O. octandra and B. vulgaris; with A. heterophyllus a maximum effect was not observed even at +5 hr. 4. The hypoglycaemic activity of O. octandra was comparable with that of tolbutamide while that of A. heterophyllus or B. vulgaris was better than that of tolbutamide. 5. The magnitude of the hypoglycaemic effects varied with the dosage used and the time of storage (except with A. heterophyllus, whose activity did not change with storage even up to 3 days).     

Anti-inflammatory activity of some Saudi Arabian medicinal plants

Five plants which have been used for the treatment of rheumatism, arthritis and gout in the traditional medicine of Saudi Arabia, were evaluated for their anti-inflammatory properties. Of these the ethanolic extract of Capparis decidua and the aqueous extract of Capparis spinosa were found to possess significant anti-inflammatory activity against carrageenan induced oedema in rats. These two plants were also tested for their antipyretic and analgesic activity. C. decidua was found to possess significant antipyretic effect. Both of them are devoid of analgesic activity.     

Screening of Korean medicinal plants for antitumor activity

Potential antitumor activity of sixteen Korean medicinal plants was tested against leukemia SN 36, murine tumor model. Survival studies by measuring life span indicated thatMorus alba (Moraceae), Verbascum phlomoides (Scrophulariaceae), Curcuma longa (Zingiberaceae), Torilis japonica (Umbelliferae), Bupleurum falcatum (Umbelliferae) andCodonopsis pilosula (Campanulaceae) exhibited significant antitumor activity with the dose-schedule employed in the experiment. Methanol(70%) extracts ofPlatycodon grandiftorum (Campanulaceae), Bupleurum longeradiatum (Umbelliferae) andAsiasarum sieboldii (Aristolochiaceae) showed rather potent toxicity.     

芳香药用植物的抗氧化活性成分及其药理作用研究进展

目的我国芳香药用植物资源丰富,种类繁多,应用广泛。芳香药用植物因兼具芳香植物与药用植物2个类群的属性,成为国内外的研究热点,而具有抗氧化性质的芳香药用植物更是成为合成抗氧化剂的最佳潜在替代品。本文综述了近年来国内外芳香药用植物在抗氧化活性成分和药理作用方面的研究,并对芳香药用植物资源的充分利用与进一步研究进行展望,旨在为具有抗氧化活性的芳香药用植物在食品、药品、保健品和化妆品等方面的应用提供一定的理论依据。     

The antibacterial and antifungal activity of essential oils extracted from Guatemalan medicinal plants

Abstract

Context: Essential oils are prevalent in many medicinal plants used for oral hygiene and treatment of diseases.

Objective: Medicinal plant species were extracted to determine the essential oil content. Those producing sufficient oil were screened for activity against Staphylococcus aureus, Escherichia coli, Streptococcus mutans, Lactobacillus acidophilus, and Candida albicans.

Materials and methods: Plant samples were collected, frozen, and essential oils were extracted by steam distillation. Minimum inhibitory concentrations (MIC) were determined using a tube dilution assay for those species yielding sufficient oil.

Results: Fifty-nine of the 141 plant species produced sufficient oil for collection and 12 species not previously reported to produce essential oils were identified. Essential oil extracts from 32 species exhibited activity against one or more microbes. Oils from eight species were highly inhibitory to S. mutans, four species were highly inhibitory to C. albicans, and 19 species yielded MIC values less than the reference drugs.

Discussion: Results suggest that 11 species were highly inhibitory to the microbes tested and merit further investigation. Oils from Cinnamomum zeylanicum Blume (Lauraceae), Citrus aurantiifolia (Christm.) Swingle (Rutaceae), Lippia graveolens Kunth (Verbenaceae), and Origanum vulgare L. (Lamiaceae) yielded highly significant or moderate activity against all microbes and have potential as antimicrobial agents.

Conclusion: Teas prepared by decoction or infusion are known methods for extracting essential oils. Oils from 11 species were highly active against the microbes tested and merit investigation as to their potential for addressing health-related issues and in oral hygiene.