Genotoxicity of polar and apolar extracts obtained from Qualea multiflora and Qualea grandiflora

Ethnopharmacological relevance

The species Qualea grandiflora and Qualea multiflora, which belong to the Vochysiaceae family, are common in the Brazilian savannah (Cerrado biome), and the local inhabitants use these species to treat external ulcers and gastric diseases and as an anti-inflammatory agent. Studies have demonstrated that these plants contain compounds that exhibit pharmacological activities; however, the risks associated with their consumption are not known.

Material and methods

In the present study, the mutagenicity of polar and apolar extracts from Qualea grandiflora and Qualea multiflora were assessed by employing the Ames assay with and without metabolic activation. Additionally, phytochemical analyses (HPLC-ESI-IT-MS, HPLC-UV-PDA and GC-IT-MS) were performed to identify the chemical constituents present in these species, including the evaluation of physico-chemical properties, such as polarity or apolarity of the organic compounds, which are related to each fraction obtained. These studies provide important information regarding the biochemical behaviour of these compounds.

Results

All extracts exhibited mutagenicity, inducing frameshift mutations and base substitutions in DNA. Phytochemical analysis identified terpenes, ellagic acid derivatives and phytosteroids.

Conclusions

The mutagenicity observed might be due to the presence of pentacyclic triterpenes and polyphenols, which are able to generate reactive oxygen species (ROS) and result in the potential to cause DNA damage. The genetic risk identified in this present work shows that special attention should be considered for the use of compounds obtained from these plant species in medicinal treatments. Further studies must be conducted to identify safe therapeutic doses.     

Analysis of the phytochemical contents and antioxidant activities of crude extracts from Tulbaghia species

OBJECTIVE: To assess the phytochemical contents and antioxidant activities of crude extracts from selected Tulbaghia species.METHODS: Standard methods were used for preliminary phytochemical analysis. The total phenolic acid contents of the plant extracts were determined using the Folin-Ciocalteu method, and the total flavonoid contents were determined using the aluminum chloride colorimetric method. 1,1-Diphenyl-2-picrylhydrazyl and 2,2′-Azino-bis(3-ethylbenzthiazoline-6-sulfonic acid) assays were used to evaluate the antioxidant activities.RESULTS: Phytochemical screening showed flavonoids, glycosides, tannins, terpenoids, saponins,and steroids were present in the Tulbaghia species.The total phenolic acid and flavonoid contents varied in the different plant extracts, ranging from4.50 to 11.10 mg of gallic acid equivalents per gram of fresh material and 3.04 to 9.65 mg of quercetin equivalents per gram, respectively. The IC50 values determined for Tulbaghia alliacea and Tulbaghia violacea based on 1,1-diphenyl-2-picrylhydrazyl(0.06 and 0.08 mg/m L, respectively) and 2,2′-Azino-bis(3-ethylbenzthiazoline-6-sulfonic acid)(0.06 and 0.03 mg/m L, respectively) were low and showed they had potential antioxidant activities.CONCLUSION: Our results suggest that individual compounds from Tulbaghia species should be isolated for analysis of their antioxidant activity because some compounds may work best when pure.     

Biological activities of crude plant extracts from Vitex trifolia L. (Verbenaceae)

Biological assays of Vitex trifolia L. organic extracts have shown relevant activities. Hexanic and dichloromethanic (DCM) extracts, when prepared from stems and foliage, have proved to be very toxic against several cancer cell lines in culture (SQC-1 UISO, OVCAR-5, HCT-15 COLADCAR, and KB). Also, an important antifeeding activity against the insect pest Spodoptera frugiperda (Lepidoptera: Noctuidae) was recorded. The hexanic extract from leaves completely inhibited the growth of the fungal plant pathogen Fusarium sp. within the first 2 days of the experiment, but dropped significantly at day 6 (15% inhibition). The potential of V. trifolia for several uses is discussed.     

Pharmacological action of aqueous crude extracts of Artemisia verlotorum Lamotte (Compositae)

The pharmacological study of the responses evoked by a dried aqueous extract of Artemisia verlotorum on different guinea-pig and rat isolated organs in vitro, suggests a possible muscarinic activity as a cause of the antihypertensive activity. The ability of atropine, in ileum preparations, and of N_ω-nitro L -arginine methyl ester, in aortic preparations, to inhibit the plant effects seems to confirm the muscarinic nature of the responses © 1997 John Wiley & Sons, Ltd.     

Antibacterial and antioxidant activities of ethanol extract from Paullinia cupana Mart

The antibacterial and antioxidant activity of the ethanol extract from Paullinia cupana var. sorbilis Mart. (Sapindaceae) seeds, commonly called guarana, was assessed towards selected bacteria as well as in different antioxidant models. The extract, at a concentration between 16 and 128 microg/ml, showed a significant antibacterial effect expressed as minimum inhibitory concentration (MIC) against both Gram-negative and Gram-positive bacteria. In particular, Pseudomonas aeruginosa (MIC=16 microg/ml), Proteus mirabilis (MIC=32 microg/ml), Proteus vulgaris (MIC=32 microg/ml) and Escherichia coli (MIC=32 microg/ml) were the most inhibited. The antioxidant activity was determined by the malonyldialdehyde (MDA) test, measuring the MDA concentration in 3T3-L1 cells after induced cellular damage using ferric ammonium citrate (FAC). The reduction of lipid peroxidation was 62.5% using a guarana extract with a concentration of 2 microg/ml. This effect was dose/dependent. The ethanol extract from Paullinia cupana seeds was analysed by spectrophotometry to determine the concentration of catechol substances after treatment of the extract with p-aminophenol. The total phenolics content in the ethanol extract was also determined spectrophotometrically according to the Folin-Ciocalteu procedure and calculated as gallic acid equivalents (GAE). The concentration of catechol equivalent was 6.06+/-0.13 mg/g (mean+/-S.D.), while the total phenolic content was 8.43+/-0.21 mg/g (mean+/-S.D.). The correlation index between antioxidant activity and catechol content was 0.96.     

五倍子降血糖有效组分的药理筛选

 目的筛选中药五倍子降血糖作用的有效组分,比较提取工艺对降血糖活性的影响。方法采用不同极性溶剂提取并结合化学处理与柱色谱分离,获得五倍子各不同组分,以四氧嘧啶致家兔高血糖模型及链脲佐菌素致小鼠糖尿病模型对各组分的降血糖活性进行比较;并以对链脲佐菌素所致小鼠糖尿病模型的影响为依据,比较提取工艺对降血糖活性的影响。结果五倍子石油醚提取物有明显的降血糖活性,其中脂肪油类成分为降血糖有效组分;进一步的化学与柱色谱分离均导致降血糖活性降低;溶剂提取与CO₂超临界提取所得五倍子油降血糖活性无明显差异(P>0.05)。结论五倍子石油醚提取物有明显降血糖作用,其有效组分为其脂肪油。     

Analgesic and antimalarial activities of crude leaf extract and fractions of Acalypha wilkensiana

Aim of the study

Antiplasmodial and analgesic activities of leaf extract and fractions of Acalypha wilkensiana were evaluated to ascertain the folkloric claim of its antimalarial and analgesic activities.

Materials and methods

The crude leaf extract (220–659 mg/kg) and fractions (chloroform and aqueous; 440 mg/kg) of Acalypha wilkensiana were investigated for antiplasmodial activity against chloroquine sensitive Plasmodium berghei infections in mice and for analgesic activity against chemical and heat-induced pains. The antiplasmodial activity during early and established infections as well as prophylactic activity were investigated. Chloroquine (5 mg/kg) and pyrimethamine (1.2 mg/kg) were used as positive controls. Thin films made from tail blood of each mouse were used to assess the level of parasitaemia of the mice. Analgesic activity of the crude extract was also evaluated against acetic acid, formalin and heat-induced pains.

Results

The extract and its fractions dose-dependently reduced parasitaemia induced by chloroquine sensitive Plasmodium berghei infection in prophylactic, suppressive and curative models in mice. These reductions were statistically significant (p < 0.001). They also improved the mean survival time (MST) from 16 to 22 days relative to control (p < 0.01–0.001). The activities of extract/fractions were incomparable to that of the standard drugs used (chloroquine and pyrimethamine). On chemically and thermally induced pains, the extract inhibited acetic acid and formalin-induced inflammation as well as hot plate-induced pain in mice. These inhibitions were statistically significant (p < 0.001) and in a dose-dependent fashion.

Conclusion

The antiparasitaemic and analgesic effects may in part be mediated through the chemical constituents of the plant.     

Antibacterial and anti-inflammatory effects of extracts and fractions from Polygonum capitatum

Aim of the study

This study was designed to investigate the antibacterial and anti-inflammatory activities of the extracts and the structure-based fractions from P. capitatum so as to provide the evidence for the traditional use of this plant in the treatment of urinary tract infections and to clarify the structural types that were responsible for the clinical use of the plant.

Materials and methods

The dry whole plant of P. capitatum was extracted with water and 70% aqueous ethanol and then separated, respectively, into a fraction enriched in polysaccharides and proteins (PP) and four other fractions enriched in gallic acid and its analogues (GAA), flavonoids (FV), tannins (TN), and triterpenoids and steroids (TS). UV spectral or chemical methods were used for the confirmation of the five fractions. The in vitro antibacterial activities of the aqueous (AE) and 70% aqueous ethanol (70EE) extracts as well as the fractions against gram-positive and gram-negative bacteria were initially evaluated by a disc diffusion test. The anti-bacterial potencies of the active extracts or fractions were then assessed in vitro by determining the MICs and MBCs. The anti-inflammatory activity was evaluated employing the xylene-induced mouse ear edema model.

Results

Except for fraction PP, AE, 70EE, and the four fractions (GAA, FV, TN, and TS) exhibited varying degrees of antibacterial and anti-inflammatory activities. The results of the minimal inhibition concentration (MIC) and minimal bactericidal concentration (MBC) indicated that the crude extracts or fractions FV and TN all possess bacteriostatic and bactericidal properties. Fractions FV and TS showed significantly anti-inflammatory activity (P < 0.01) with the inhibition rates of 86.15 and 73.71% at 0.6 g/kg, respectively, as compared to 76.93% of the positive control dexamethasone.

Conclusions

The overall results suggested that the traditional use of this plant for the treatment of urinary tract infections were attributed to the presence of antibacterial and anti-inflammatory agents. The results also provided evidence that the studied plant extracts, as well as some of the fractions obtained from this plant might be potential sources for antimicrobial and anti-inflammatory drug development.     

普洱茶提取物的抗HIV活性(英文)

目的:研究普洱熟茶(发酵)和普洱绿茶(未发酵)这 2 种常见普洱茶的抗 HIV 作用。方法:采用 MTT 比色法检测普洱茶提取物对 C8166, MT4 和 PBMC 细胞的毒性作用; 细胞病变法检测化合物对 HIV-1 急性感染的抑制活性。采用细胞病变法和 HIV-1 p24 抗原 ELISA 方法检测普洱茶提取物的抗 HIV 活性作用; 结果:所有普洱茶提取物都具有较低的细胞毒性 CC50为 120.63 524.95 μg·mL 1。所有普洱茶提取物均能抑制 HIV 诱导细胞形成合胞体其 EC50为 11.13 67.49 μg·mL 1。普洱茶水提物的抑制作用比醇提物的抑制作用要好, 并且普洱熟茶的抑制作用好于普洱生茶, 尤其是 YYP-31, 其 SI 值为 42.40。YYP-31 对HIV-RF和 HIV-2CBL-20也有很好的抑制作用, 其 EC50分别为 30.82 和 39.79 μg·mL 1。YYP-31 还能很好地抑制 HIV-1IIIB急性感染C8166 细胞和 HIV-1KM018感染PBMC细胞p24抗原的产生, 其EC50分别为14.95和 74.63 μg·mL 1。YYP-31能阻止正常细胞C8166与 HIV-1 慢性感染细胞 H9/HIV-1IIIB之间的融合, EC50为 234.27 μg·mL 1。提取物 YYP-31 与 AZT 联合用药具有显著的协同抗HIV 作用,但是对 HIV 逆转录没有抑制作用。结论:普洱茶提取物具有很好的抗 HIV 的活性作用, 可以作为一种 HIV 辅助治疗的产品或保健品用于 HIV 患者的治疗过程中。     

Antimalarial activity of crude extracts from nine African medicinal plants

An ethnobotanical study was conducted in Comores (Ngazidja) about plant species used traditionally for the treatment of various diseases, including malaria. Antimalarial activity of 76 vegetal extracts obtained from 17 species traditionally used to treat malaria symptoms, was evaluated in vitro using Plasmodium falciparum chloroquine-resistant strain (W2). Antiproliferative activity was evaluated on human monocytic THP1 cells and the selectivity index of the plant extracts was calculated. The results showed that 10 plant extracts had a moderate activity (5相似文献   

Study on anti-diabetic activities of crude methanolic extracts of Loranthus micranthus (Linn.) sourced from five different host trees

The hypoglycaemic and anti-hyperglycemic activities of dried leaves of Loranthus micranthus (Linn.) (Loranthaceae), parasitic on Persea americana, Baphia nitda, Kola acuminata, Pentaclethra macrophylla, Azadirchta indica, were evaluated in normoglycemic and alloxan-induced diabetic albino rats. Normoglycemic and alloxan-induced diabetic rats were treated (intraperitoneally) with 200 mg/kg of the respective methanolic extracts of Loranthus micranthus (Linn.), glibenclamide (positive control), and 20% (v/v) Tween 20 solution (negative control). The sugar levels of the withdrawn blood samples were determined by o-toluidine spectrophotometric method. The studies indicate that the crude methanolic extract of Loranthus micranthus (Linn.) exhibited statistically significant hypoglycaemic (P < 0.001) and anti-hyperglycemic (P < 0.001) activities in normoglycemic and alloxan-induced diabetic albino rats, respectively. The hypoglycaemic effect was found to be dose-dependent. The maximum effect of the mistletoe extract (400 mg/kg) from Persea americana on alloxan-induced diabetic rats was found to be statistically comparable with that of the positive control, glibenclamide, at 24 h after administration, with a percentage reduction of blood sugar levels of 82.59 and 83.34%, respectively. Acute toxicity tests of the methanolic extracts of Persea americana, Baphia nitda, Kola acuminata, Pentaclethra macrophylla, Azadirchta indica host trees in mice gave LD(50) values of 11650, 11650, 5900, 5900 and 5900 mg/kg, respectively, which are all within the practically non-toxic range. The methanolic extract of African mistletoe was found to be a good candidate for alternative and/or complimentary medicine in the management of diabetes mellitus. The leaves of the Eastern Nigerian species of the African mistletoe harvested from Kola acuminata, Azadirchta indica and Baphia nitda host trees exhibited comparatively better anti-hyperglycemic activities among the host trees studied.     

Antiinflammatory activity of extracts and fractions from the leaves of Gochnatia polymorpha

The aqueous and ethanol extracts from the leaves of Gochnatia polymorpha and further fractions obtained from the latter extract using solvents with increasing polarity, including its aqueous residue and the amino acid, 4-hydroxy-N-methyl-proline were investigated by carrageenin-induced pedal oedema formation. It was shown that the aqueous and ethanol extracts and the ethyl acetate fraction demonstrated significant antiinflammatory activity. The chemical investigation of the latter fraction revealed the presence of caffeic acid, chlorogenic acid, 3-0-methylquercetin, hyperosid and rutin. The amino acid 4-hydroxy-N-methyl-proline, a nonprotein amino acid that has not been reported before in the Asteraceae was isolated as a major compound and identified by spectroscopic methods.     

苦瓜蛋白的药用价值

苦瓜为葫芦科苦瓜属植物，从中提取的蛋白质成分包括：蛋白酶抑制剂、核糖核酸酶、核糖体失活蛋白等，具有比较广泛的药理学作用。MAP30等可以通过使核糖体失活，抑制肿瘤细胞蛋白质的合成，抑制肿瘤细胞的生长；通过抑制T细胞的增长，抑制HIV病毒的复制，达到治疗艾滋病的目的。笔者着重对其抗肿瘤作用及抗艾滋病作用进行了综述，认为苦瓜蛋白成分的开发和应用给恶性肿瘤和艾滋病的治疗提供了新的思路，具有潜在的开发应用前景。     

Antibacterial activities of extracts from Nigerian chewing sticks

Ten aqueous extracts from wooden chewing sticks widely used in Nigeria for teeth cleaning were studied for antibacterial activities against 25 different bacteria using an agar diffusion assay. The extracts from five sticks, namely Garcinia kola, Anogeissus leiocarpus, Terminalia glaucescens, Sorindeia warneckei and Vitex doniana, exhibited strong activities against a wide spectrum of bacteria including medically and dentally relevant bacteria. Notably, these five chewing stick extracts showed potent activities against methicillin-resistant Staphylococcus aureus, vancomycin-resistant Enterococcus, and multidrug-resistant Burkholderia cepacia and Pseudomonas aeruginosa. Extracts from Vernonia amygdalina, Fagara zanthoxyloides and Massularia acuminata also showed activities against bacteria significant to periodontal disease. Methanol extracts prepared from G. kola, A. leiocarpus and V. doniana were further fractionated by solvent extraction. Results showed that the antibacterial activities were distributed into different fractions suggesting that the sticks contain different active antibacterial principles. In conclusion, the results showed that most of the Nigerian chewing sticks do contain antibacterial activities which may contribute to the reported anticaries effect of chewing sticks. These sticks may be sources for new lead antibacterial agents for therapeutic or preventive applications.     

In vitro antimalarial activity of crude extracts and compounds from Artemisia abrotanum L

Artemisia abrotanum L. (Compositae) is widely used in European herbal medicine for treatment of various ailments including fever. Crude extracts of this plant and some of their constituents were tested for antimalarial activity against Plasmodium falciparum in vitro using the technique of [³H]hypoxanthine incorporation. Two pure compounds, isofraxidin and a novel sesquiterpene, 1(S*)-hydroxy-α-bisabololoxide A acetate were found to be active (IC₅₀ values of 7.95 and 5.09 m?g/mL, respectively).     

Lipoxygenase inhibitory activity of crude bark extracts and isolated compounds from Commiphora berryi

Ethnopharmacological relevance

Commiphora berryi is traditionally used for the treatment of cold and fever as well as for wound healing in the southern parts of India.

Aim of study

The present study was designed to investigate in vitro soybean lipoxygenase inhibitory activity of crude extracts and compounds isolated from Commiphora berryi.

Materials and methods

The bark of Commiphora berryi was extracted with different organic solvents and subjected to chromatographic separation for isolation of bioactive compounds. Structures of isolated compounds were elucidated by spectroscopic methods. The anti-inflammatory activity of bark extracts and bioactive compounds were assessed by in vitro soybean lipoxygenase (SBL) assay.

Results

3β-Hydroxyglutin-5-ene (1), friedelin (2), cycloeucaneol (3) nimbiol (4), sugiol (5), surianol (6), daucosterol (7) and ursolic acid (8) were isolated from crude bark extracts of the Commiphora berryi. The structure of nimbiol (4) was also confirmed by single crystal X-ray analysis. The petroleum ether, methanol, chloroform and ethyl acetate extracts of bark of Commiphora berryi showed SBL inhibitory activity with the IC₅₀ values of 15.3, 54.2, 71.5 and 87.8 μg/ml respectively. Among all the isolates, friedelin (2) showed significant SBL inhibitory activity with IC₅₀ 35.8 μM.

Conclusion

The overall results provide evidence that the studied plant might be a potential source of anti-inflammatory agents.     

Pharmacological activity of Guarana (Paullinia cupana Mart.) in laboratory animals

Mice that ingested a suspension of guarana (Paullinia cupana, Sapindaceae) in a dose of 0.3 mg/ml showed a significant increase in physical capacity when subjected to a stressful situation such as forced swimming after 100 and 200 days of treatment. Such an effect, however, was not obtained with a concentration of 3.0 mg/ml, nor with the ingestion of a suspension of ginseng 5.0 mg/ml, nor of a solution of caffeine 0.1 mg/ml. Guarana, both after a single (3.0 and 30 mg/kg) or chronic administrations (0.3 mg/ml), was able to partially reverse the amnesic effect of scopolamine as measured through a passive avoidance test in mice and rats, indicating a positive effect on memory acquisition. However, no effect was observed when an active avoidance task was used in rats, even after 20 days of guarana administration. There was also a tendency of rats treated with 0.3 mg/ml of guarana to better maintain the memory of a Lashley III maze path. The animals had the same average lifespan, indicating a low toxicity of guarana, even after 23 months of treatment.     

Toxicity,antimicrobial and anthelmintic activities of Vernonia guineensis Benth. (Asteraceae) crude extracts

Ethnopharmacological relevance

This study examined the antibacterial, antifungal, and anthelmintic properties of extracts obtained from the plant Vernonia guineensis, a plant commonly used in traditional Cameroonian medicine.

Materials and methods

For in vitro studies, 10 g of leaf and tuber powder from V. guineensis was extracted separately using dichloromethane, methanol and distilled water. The extracts were dried in vacuo and used for antimicrobial and anthelmintic activity studies. In the antimicrobial assay, extracts were tested against bacterial and fungal organisms including; Staphylococcus aureus, Staphylococcus epidermidis, Acinetobacter baumannii, Aspergillus fumigatus, Candida albicans and Trichophyton mentagrophytes. In the anthelmintic assay, larval and adult stages of the hookworm Ancylostoma ceylanicum and the mouse nematode Trichuris muris were used. For the acute toxicity test, male and female rats of 150–200 g body weight were used in the experiment. The aqueous extract of V. guineensis tubers was administered in 4 doses of 500, 1000, 2000 and 4000 mg/kg per group (n=6), respectively, and the control group received distilled water.

Results

The crude extracts exhibited weak antibacterial and antifungal activity except for the dichloromethane extract, which showed moderate activity against A. fumigatus (MIC=200 μg/ml). In the anthelmintic assay, the organic extracts of the tubers had 100% killing efficacy against T. muris at 2 mg/ml in 48 h, while the aqueous extract showed no activity. The organic leaf extracts demonstrated potent activity killing 100% of the adult worms 1 mg/ml in 24 h. The aqueous leaf extract was active at 2 mg/ml in 72 h, killing 100% of the adult worms. In the acute toxicity test, V. guineensis did not produce any toxic signs or death at the maximum concentration of 4000 mg/kg.

Conclusion

Crude extracts from V. guineensis possess anthelmintic activity against T. muris with only weak antibiotic activity. Acute administration of aqueous extract from V. guineensis tubers did not produce toxic effects in rats. The absence of acute toxicity at the highest concentration tested indicates that the tea decoction from V. guineensis extract is safe at concentrations ≤4000 mg/kg.     

Antibacterial activity of crude extracts from Mexican medicinal plants and purified coumarins and xanthones

Thirty-two extracts from 22 Mexican medicinal plants of 15 different families were assayed to determine their antibacterial activity against Escherichia coli and Staphylococcus aureus. Seventeen plants showed antibacterial activity, while five plants showed no activity against both bacteria. All of the extracts showed higher activity against Staphylococcus aureus (methicillin-sensitive and methicillin-resistant) than against Escherichia coli, except one. Among the plants examined, Bursera simaruba (L.) Sarg. (Burseraceae), Haematoxylum brasiletto H. Karst. (Fabaceae), Calophyllum brasiliense Cambess. (Clusiaceae), and Mammea americana L. (Clusiaceae) were highly active against Staphylococcus aureus. Coumarins (mammea A/BA and mammea A/AA) and xanthones, namely jacareubin and 1,3,5,6-tetrahydroxy-2-(3,3-dimethylallyl) xanthone, were isolated as the principle compounds from the last two plants.