Anti-anaphylactic effect of Euphorbia hirta

The Euphorbia hirta ethanolic extract (EH A001) was found to possess a prominent anti-anaphylactic activity. A preventive effect of EH-A001 given by oral route at dose from 100 to 1000 mg/kg was observed against compound 48/80-induced systemic anaphylaxis. At the same range of dose, EH-A001 inhibited passive cutaneous anaphylaxis (PCA) in rat and active paw anaphylaxis in mice. A suppressive effect of EH-A001 was observed on the release of TNF-alpha and IL-6 from anti-DNP-HSA activated rat peritoneal mast cells.     

Antimutagenic, antioxidant and antimicrobial properties of Maytenus krukovii bark

The hydroalcoholic extract of Maytenus krukovii bark was investigated for its in vitro mutageno-protective activities by means of the Ames Salmonella/microsome assay. The extract showed an inhibitory effect in both T98 and T100 strains against the mutagenic activity of promutagen 2-aminoanthracene but was not protective against directly acting mutagens sodium azide and 2-nitrofluorene. When tested as a radical scavenger and antioxidant it produced a dose-dependent inhibition. The extract did not show significant antibacterial properties, and was weakly active against dermatophyte and phytopathogenic fungi, but inhibited the growth of phytopathogen Pithyum ultimum.     

Antioxidant and antibacterial activities of aqueous extract of Seabuckthorn (Hippophae rhamnoides) seeds

Seabuckthorn (Hippophae rhamnoides) seeds aqueous extract was screened for antioxidant and antibacterial activities. The antioxidant activities (reducing power, DPPH and liposome model system) showed a good antioxidant activity. The extract was also found to possess antibacterial activity with a MIC values with respect to Listeria monocytogenes and Yersinia enterocolitica found to be 750 and 1000 ppm, respectively. The antioxidant and antimicrobial effects of the extract implicate its potential for natural preservation.     

Antidiabetic activity of hydro-ethanolic extract of Cyperus rotundus in alloxan induced diabetes in rats

In light of the traditional claim of Cyperus rotundus in the treatment of diabetes, investigations were carried out to evaluate its effect on alloxan induced hyperglycemia in rats. Oral daily administration of 500 mg/kg of the extract (once a day for seven consecutive days) significantly lowered the blood glucose levels. This antihyperglycemic activity can be attributed to its antioxidant activity as it showed the strong DPPH radical scavenging action in vitro.     

不同采收时期对香椿饲用品质的影响

[目的]对不同采收时期所得香椿复叶的粗蛋白、类黄酮、总硝酸盐含量及其抗氧化活性进行分析比较,确定饲用香椿复叶的最佳采收时期。[方法]以5月15日至11月1日逐月采收的香椿复叶为材料,测定其粗蛋白、类黄酮及总硝酸盐含量,并利用ORAC、DPPH、FRAP法测定其抗氧化活性,综合营养及保健活性分析,筛选最适饲用采收时期。[结果]不同采收期,香椿复叶粗蛋白、类黄酮、硝酸盐含量及抗氧化活性差异显著(P0.05)。其中,复叶粗蛋白含量(全采收期13.17%～22.65%)随其成熟度增加而呈下降趋势,除10月中旬后的样品外,其余采收期复叶粗蛋白含量均大于15%,远高于常规粮食饲料,具有高蛋白的饲用优势;类黄酮含量突出(全采收期均值15.87 mg·g~(-1)),远高于蓝莓等常见果蔬,且随复叶成熟而持续积累,并于10月达到最高27.02 mg·g~(-1);ORAC、DPPH、FRAP法测定结果均表明香椿复叶具有突出的抗氧化活性,且随复叶成熟而持续增加,并与其类黄酮含量呈极显著正相关(P0.01);香椿复叶大量富集硝酸盐(全采收期2 306.39～7 346.80 mg·kg~(-1)),且随其叶片成熟呈"V"形积累,7—8月中旬采收的香椿复叶硝酸盐含量处峰谷阶段,此间均值为2 603.78 mg·kg~(-1),相对适于进行饲用采收。[结论]不同采收期香椿复叶的饲用品质差异显著,综合考虑其营养价值及保健功效, 7—8月中旬是对香椿复叶进行饲用采收的最适采收时期。     

Protective effect of saponins from Argania spinosa against free radical-induced oxidative haemolysis

Saponins from Argania spinosa at a non-haemolytic concentration diminish by 53.2% erythrocyte haemolysis induced by free radicals. 2 mM aspirin and acetaminophen diminish by 75% and 68% , respectively, erythrocyte haemolysis induced by free radicals, while 0.3 muM vitamin E shows no significant antioxidant activity. Interestingly, a combination of 1 mg/l of A. spinosa saponins and vitamin E at 0.3 muM resulted in a 68% level of protection against free radical-induced erythrocyte haemolysis, which may suggest that A. spinosa saponins enhance the antioxidant effect of vitamin E. In contrast, no synergic effect was observed for acetaminophen (2 mM) when in combination with vitamin E (0.3 muM). These results demonstrate the antioxidant properties of saponins from A. spinosa and their ability to potentate the antioxidant effect of vitamin E.     

Antioxidant activity of Litsea cubeba

The antioxidant activity of Litsea cubeba was studied in terms of three different assay systems: DPPH assay, peroxidase/guaiacol assay, and TBA test. The L. cubeba methanol extract and its fractions showed remarkable antioxidant activity in comparison with alpha-tocopherol and ascorbic acid.     

Morphological evidences for onion-induced growth inhibition of Trichophyton rubrum and Trichophyton mentagrophytes

The antifungal activity of onion (Allium cepa L.) on two important dermatophytes, Trichophyton rubrum and Trichophyton mentagrophytes, with special reference to morphological aspects was studied. Growth of both fungi was found to be strongly inhibited by aqueous onion extract (AOE) as a dose-dependent manner. The extract showed fungicidal effect for both fungi at concentrations >3.12% (v/v). The fungus T. mentagrophytes was more affected by the onion as compared to T. rubrum at all concentrations used. Morphological effects of onion exposure were examined in correlation with fungal growth. Corresponding to the growth inhibition, light and electron microscopy observations revealed morphological anomalies in hyphal compartments. The results demonstrated that AOE targets the cell membrane of the fungi as breaking down of both inner and outer membranes with consequent extrution of materials into the surrounding medium. Cytoplasmic membranes and other membranous structures of organelles, such as nuclei and mitochondria, were also disrupted. In correlation to the fungal growth, morphological alterations occurred to a less content for T. rubrum compared with T. mentagrophytes. The hyphae of T. rubrum were found to be mainly affected by converting to resistant forms, i.e., chlamidospores as a consequence of phenotype switching response to AOE. Plasmolysis accompanied by an almost complete depletion and disorganization of cytoplasmic structures were found to be the final event which led to cell death. Ultrastructural evidences obtained from this study strongly support that morphological changes of T. rubrum and T. mentagrophytes caused by AOE are associated with its fungistatic and fungicidal activities. With respect to the morphological results and the preliminary data on fungal biochemistry, a mechanism of action by interacting of AOE with thiol (-SH) groups present in essential compartments of the fungal cells was postulated.     

Triptolide ameliorates Crohn's colitis is associated with inhibition of TLRs/NF-κB signaling pathway

Growing evidence suggests that TLRs/NF-κB signaling pathway plays a critical role in the pathogenesis of Crohn's disease (CD). We have reported that triptolide, an active component from Tripterygium wilfordii Hook, showed therapeutic activity in IL-10-deficeint (IL-10⁻/⁻) mice, a murine CD model. However the full mechanisms of action of this agent in CD remain largely unknown. We hypothesized that triptolide would ameliorate the experimental colitis by inhibiting TLRs/NF-κB signaling pathway. We found TLR2 and TLR4 were upregulated in IL-10⁻/⁻ mice, triptolide inhibited the TLRs/NF-κB signaling pathway in vivo. In addition, triptolide in vitro was able to downregulate the TLRs/NF-κB pathway in cultured colonic explants from CD patients. Our results confirm the therapeutic effect of triptolide in experimental colitis, and suggest it as a promising compound for CD treatment. These findings also support the possibility that targeted inhibition of TLR signaling pathway is an approach deserving further investigation as a therapeutic strategy for CD.     

Preventive effect of Kaempferia parviflora ethyl acetate extract and its major components polymethoxyflavonoid on metabolic diseases

Previously, we reported that rhizome powder of Kaempferia parviflora Wall. Ex. Baker prevented obesity and a range of metabolic diseases. In this study, to clarify which molecular mechanisms and active ingredients of K. parviflora have an anti-obesity effect, we investigated the effect of ethyl acetate extract of K. parviflora (KPE) on TSOD mice, a spontaneously obese Type II diabetes model, and on pancreatic lipase. In the TSOD groups, KPE showed a suppressive effect on body weight increase and visceral fat accumulation and also showed preventive effects on symptoms related to insulin resistance, hypertension and fatty liver. In addition, KPE also suppressed body weight increase and food intake in TSNO mice groups, which served as reference animals, at an early stage of administration. Searching for the ingredients in KPE revealed that KPE contains at least 12 kinds of polymethoxyflavonoid (PMF). Furthermore, KPE and its component PMFs showed an inhibitory effect on pancreatic lipase. The above results suggest that KPE has a preventive effect on obesity and various metabolic diseases. The mechanisms of action probably involve inhibition of pancreatic lipase by the PMFs in KPE.     

In vitro antioxidant and antibacterial activity of Rhaphidophora pertusa stem

Methanol extract of Rhaphidophora pertusa stem was analyzed for its antioxidant (DPPH, reducing power and Fe(3+) metal chelation methods) and antibacterial activities. The extract was found effective against the three antioxidant test models and exhibited strong and moderate antibacterial activity against the tested pathogenic bacteria.     

Effects of Erigeron breviscapus ethanol extract on neuronal oxidative injury induced by superoxide radical

Antioxidant activity of the ethanol extract of Erigeron breviscapus (EEEB) were studied by using neuron oxidative injury model induced by superoxide radical. EEEB at the dose of 10-140 mug/ml reduced significantly the lipid peroxidation levels and lactic dehydrogenase (LDH) release from neuron exposed to superoxide radical (generated by xanthine and xanthine oxidase). These results suggest that neuroprotective actions of EEEB may be due to its antioxidant or radical scavenging activity.     

印度黄檀叶多酚提取工艺优化及抗氧化活性研究

目的]印度黄檀叶含有多酚及类黄酮物质,研究印度黄檀叶多酚及其抗氧化活性,可为其利用提供依据。[方法]以印度黄檀叶为原料,乙醇为提取液,经单因素实验与正交试验设计,检测在不同乙醇浓度、提取时间、提取温度及超声功率120 w时3个因素进行响应面优化试验,确定印度黄檀多酚的提取工艺;同时,鉴定印度黄檀叶乙醇-水提取液对DPPH-自由基的清除能力。[结果]低浓度印度黄檀叶多酚能发挥更强的抗氧化能力,其提取液对清除DPPH自由基的半数抑制质量浓度(IC_(50))约为3.2 mg·L~(-1),略大于Vc的2.5 mg·L~(-1);不过,其还原能力略低于Vc。[结论]印度黄檀叶内富含多酚类物质,具有很强的体外抗氧化活性,可作为天然抗氧化植物资源开发利用。     

Antioxidant activity of Viscum album ssp. album

Methanolic extracts of Viscum album ssp. album (mistletoe) grown on different host trees were investigated for their potential antioxidant activity. Scavenging activity was tested by 1,1­diphenyl­2­picrylhydrazyl (DPPH) method and the inhibitory effect on lipid peroxidation was examined by ferric thiocyanate and thiobarbituric acid methods. The extract from mistletoe grown on lime tree in summer showed the highest activity. It was found that antioxidant capacity of the plant differed according to the harvesting time as well as the host tree.     

Antioxidant compounds from <Emphasis Type="Italic">Eucalyptus grandis</Emphasis> biomass by subcritical liquid water extraction

The effectiveness of subcritical liquid water processing for extraction of antioxidants from the leaves of Eucalyptus grandis biomass was evaluated by determining the capability of the processed samples to scavenge peroxynitrite radicals in vitro, as compared with the extracts obtained by conventional extraction. Pyrogallol (1), 5-hydroxymethyl-2-furaldehyde (2), and 4,4,6,6-tetramethyl-3,5-dioxo-cyclohex-1-enecarboxylic acid (3) were identified as the major products obtained from the subcritical liquid water extracts. Among these, pyrogallol (1) exhibited stronger antioxidant activity than butylated hydroxytoluene, which was used as a standard for the antioxidant activity measurement. This research was presented at the conference of the Japan Society for Bioscience, Biotechnology, and Agrochemistry (JSBBA) in Tokyo, March 2007.     

Introducing GIS-modelling into the management of a brown rat (Rattus norvegicus Berk.) (Mamm. Rodentia Muridae) population in an urban habitat

The landscape of three test areas of an urban environment was efficiently assessed for its ability to support brown rats (Rattus norvegicus Berk.) by successfully integrating habitat suitability modelling using GIS (Geographical Information System). The GIS model, validated using an independent set of rat observations, and a model analysis showed the potential of different habitats for rat occurrence. Because of its use of general land-cover types, the model could be applied to other cities. This model system will be used for the entire city area of Salzburg in the near future. In this publication, we present the results of the pilot GIS model.     

Hepatoprotective effect of Ginkgoselect Phytosome in rifampicin induced liver injury in rats: evidence of antioxidant activity

The protective effects of Ginkgoselect Phytosome((R)) (GBP) on Rifampicin (RMP) induced hepatotoxicity and the probable mechanism(s) involved in this protection were investigated in rats. Liver damage was induced in Wistar rats by administering rifampicin (500 mg/kg, p.o.) daily for 30 days. Simultaneously, GBP at 25 mg/kg and 50 mg/kg, and the reference drug silymarin (100 mg/kg) were administered orally for 30 days/daily to RMP treated rats. Levels of marker enzymes (SGOT, SGPT and SALP), albaumin (Alb) and total proteins (TP) were assessed in serum. The effects of GBP on lipid peroxidation (LPO), reduced glutathione (GSH), superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPX) and glutathione reductase (GR) were assayed in liver homogenates to evaluate antioxidant activity. GBP (25 and 50 mg/kg) and silymarin elicited a significant hepatoprotective activity by lowering the levels of serum marker enzymes and lipid peroxidation and elevated the levels of GSH, SOD, CAT, GPX, GR, Alb and TP in a dose dependant manner. The present findings suggest that the hepatoprotective effect of GBP in RMP induced oxidative damage may be related to its antioxidant and free radical scavenging activity.     

Inhibition of Trypanosoma cruzi by plant extracts used in Chinese medicine

In this work, we assessed the effect of extracts obtained from 17 plants used in traditional Chinese medicine. These extracts were tested in vitro with the epimastigote form of Trypanosoma cruzi, clone Bra C(15) C(2), at 27 degrees C in F-29 medium at a concentration of 100 microg/ml in axenic cultures. Allopurinol was used as reference drug. Seven plant extracts showed inhibitory activities lower than 25%. Pueraria lobata, Mahonia beaei, Dictamus dasycarpus, Kochia scoparia, Sophora flavescens and Ligustrum lucidum showed effects with inhibition values between 25% and 60%, whereas Lithospermum erythrorhizon, Saussurea lappa, Melia toosendan and Cinnamomum cassia showed the greatest inhibitory activity of 100%. The IC(50) of these extracts were: 0.4, 2.4, 1.8 and 3.9 microg/ml, respectively. The MTT assay was made and did not show cytotoxic activity. These results allowed us to suggest that L. erythrorhizon, S. lappa, M. toosendan and C. cassia could be a source of new compounds against T. cruzi.     

Antioxidant activity and constituents of extracts from the root of Garcinia multiflora

The methanolic extract of the root of Garcinia multiflora and its derived soluble fractions, namely those soluble in ethyl acetate (EtOAc), n-butanol, and water, were screened for their antioxidant activities. Among them, the EtOAc-soluble fraction exhibited the highest scavenging activity against the 1,1-dipheny1,2-picrylhydrazyl radical, the highest superoxide radical scavenging activity, and the strongest reducing power. In addition, according to the bioactivity-guided isolation, 26 specific phytocompounds, including 3 aromatics, 3 benzophenones, 3 flavonoids, 3 isocoumarins, 1 phloroglucinol, 6 steroids, and 7 xanthones, were isolated from the EtOAc-soluble fraction and identified. Of these, 2,4,3′,4′-tetrahydroxy-6-methoxybenzophenone and 1,3,6,7-tetrahydroxyxanthone were found to be the major bioactive constituents, present in the crude extract in concentrations of 3.9 and 15.6 mg/g, respectively. These two compounds had similar antioxidant activities to (+)-catechin, a well-known antioxidant.     

Bioactive polar compounds from stem bark of Magnolia officinalis

Two new phenylethanoid glycosides magnoloside D (1) and E (2), together with nine known compounds, were isolated from the polar part of methanol extract of the stem bark of Magnolia officinalis. The structures of the new compounds were established on the basis of spectral analysis. Anti-spasmodic activity of four major constituents (3, 4, 9 and 11) was tested in isolated colon of rat, compounds 3, 4, and 9 showed inhibition against acetylcholine, with the effect similar to that of magnolol and honokiol. At the same time, antioxidant activity of the isolated compounds was investigated using a DPPH and an ORAC assay. All of the compounds, except compound 8 showed potent antioxidant capacity in the ORAC assay, while compounds 1-5 and 11 exhibited potent antioxidant activity in the DPPH assay.