Antidepressant properties of some Hypericum canariense L. and Hypericum glandulosum Ait. extracts in the forced swimming test in mice

It has been shown in a previous work that the methanol extract obtained from the aerial part in blossom of Hypericum canariense L. and Hypericum glandulosum Ait. was active in the tetrabenazine and forced swimming test. In the present study, the central nervous effect of the aqueous, butanol and chloroform fractions obtained from the methanol extracts of these Hypericum species was investigated in mice, particularly in animal models of depression. It was found that the immobility time in the forced swimming test was significantly reduced by the butanol and chloroform fraction of both species assayed, producing no effects or only a slight depression on spontaneous motor activity when assessed in a photocell activity meter. In this regard, the efficacy of the chloroform extract from Hypericum glandulosum Ait. (500 mg/kg p.o.) in the forced swimming test was comparable to that of the tricyclic antidepressant imipramine (50 mg/kg p.o.). In addition, the Hypericum glandulosum chloroform fraction was also effective in antagonizing the ptosis induced by tetrabenazine. Moreover, Hypericum canariense butanol fraction and Hypericum glandulosum chloroform fraction produced a slight but significant hypothermia. Taken together, these data demonstrate that the butanol and chloroform fractions from Hypericum canariense and Hypericum glandulosum possess antidepressant-like effects in mice, providing further support for the traditional use of these plants in the Canary Islands folk medicine against central nervous disorders.     

Analgesic and topical anti-inflammatory activity of Hypericum canariense L. and Hypericum glandulosum Ait

The present study investigates the analgesic and topical anti-inflammatory activities of the infusion, methanol extract and fractions of the aerial part in blossom of Hypericum canariense L. and Hypericum glandulosum Ait. in mice. The acetic acid-induced writhing test, tail flick test and the tetradecanoylphorbol acetate (TPA)-induced ear inflammation model in mice were used to determine these effects. Our findings show that oral administration of methanol extracts, and the aqueous, butanol and chloroform fractions of both species and the infusions of Hypericum glandulosum significantly inhibit acetic acid-induced writhing in mice. Only the infusion, methanol extract and butanol and chloroform fractions of Hypericum glandulosum were significantly active in the tail flick assay, suggesting that they may have central analgesic properties. On the other hand, the topical treatment of all extracts tested from both species, with the exception of the infusions and the Hypericum canariense aqueous fraction, significantly reduced the TPA-induced ear oedema. In conclusion, the results indicate analgesic and topical anti-inflammatory activities in mice for the Hypericum species studied.     

Antidepressant effects of the methanol extract of several Hypericum species from the Canary Islands.

The aim of the present study was to investigate several neuropharmacological effects of the methanol extract of the aerial parts in blossom of Hypericum canariense, H. glandulosum, H. grandifolium and H. reflexum (Hypericaceae). These extracts did not alter significantly the locomotor activity, body temperature or the pentobarbital-induced sleeping time, with the exception of H. reflexum which significantly potentiated pentobarbital-induced sleeping time at both doses assayed (500 and 1000 mg/kg p.o.). Additionally, neither muscle relaxant nor anticholinergic activity was observed. These extracts antagonized the ptosis and/or motor depression induced by tetrabenazine and also shortened the immobility time in the forced swimming test. Moreover, the H. glandulosum and H. grandifolium extracts at 1000 mg/kg p.o. potentiated the head twitches induced by 5-HTP. These observations suggest that the methanol extract of the Hypericum species in doses of 500-1000 mg/kg p.o. possess antidepressant activity in mice, without inducing significant muscle relaxation, anticholinergic and sedative properties.     

Bioassay-guided isolation of antimicrobial benzopyrans and phloroglucinol derivatives from Hypericum species

Recently the crude methanol extracts of six Hypericum species were analysed against a panel of microorganisms and it was found that H. caprifoliatum Cham. & Schlecht., H. myrianthum Cham. & Schlecht. and H. polyanthemum Klotzsch ex Reichardt were the most active. This paper reports the activity of the hexane, chloroform and methanol fractions of these plants as well as the activity of some isolated compounds against Staphylococcus aureus determined by bioautographic procedures.     

Evaluation of the central properties of several Hypericum species from the Canary Islands

The infusions of the aerial parts in blossom of Hypericum canariense, H. glandulosum, H. reflexum and H. grandifolium (Hypericaceae) were evaluated for their pharmacological activity on the central nervous system in mice using various behavioural models including locomotor and muscle relaxant activity, effect on normal body temperature, pentobarbital-induced sleep, oxotremorine and tetrabenazine-induced syndrome, apomorphine-induced hypothermia and 5-hydroxytryptophan-induced head twitches, as well as a forced swimming test. These infusions did not alter significantly the locomotor activity, pentobarbital induced sleeping time and body temperature, with the exception of H. canariense which produced a slight but significant hypothermia. Additionally, no muscle relaxant or anticholinergic activity were observed. These infusions antagonized the ptosis and/or motor depression induced by tetrabenazine as well as shortening the immobility time in the forced swimming test. The observations suggest that the infusions of these Hypericum species possess antidepressant activity in mice, without inducing muscle relaxation, anticholinergic and sedative properties.     

Antidepressant activity of some Hypericum reflexum L. fil. extracts in the forced swimming test in mice

We previously reported that oral administration of the methanol extract obtained from the aerial part in blossom of Hypericum reflexum L. fil. was active in the tetrabenazine and forced swimming test. In the present study, the effect of the aqueous, butanol and chloroform fractions obtained from the methanol extract of this species on the central nervous system was investigated in mice, particularly in animal models of depression. Antidepressant activity was detected in the butanol and chloroform fractions of this species using the forced swimming test since both fractions induced a significant reduction of the immobility time, producing no effects or only a slight depression on spontaneous motor activity when assessed in a photocell activity meter. Moreover, these fractions did not alter significantly the pentobarbital-induced sleeping time. On the other hand, the chloroform fraction produced a slight but significant hypothermia and was also effective in antagonizing the ptosis induced by tetrabenazine. Furthermore, the butanol fraction produced a slight potentiation of the head twitches and syndrome induced by 5-HTP. Taken together, these data indicate that the butanol and chloroform fractions from Hypericum reflexum possess antidepressant-like effects in mice, providing further support for the traditional use of these plants in the Canary Islands folk medicine against central nervous disorders.     

紫金砂体外抗菌活性的研究

目的紫金砂提取物及其提取部位抗菌活性的研究。方法95%乙醇提取,系统溶剂萃取分离得到5个部位,采用纸片扩散法对提取物及提取部位进行体外抗菌活性研究。结果紫金砂提取物对金黄色葡萄球菌、大肠杆菌具有抑制作用,氯仿提取部位对大肠杆菌、枯草芽胞杆菌具有抑制作用,正丁醇提取部位对大肠杆菌、绿脓杆菌具有抑制作用。结论紫金砂提取物及提取部位具有抗菌活性。     

Evaluation of the analgesic and topical anti-inflammatory effects of Hypericum reflexum L. fil

The present study investigates the analgesic and topical anti-inflammatory effects of the infusion, methanol extract and fractions of the aerial part in blossom of Hypericum reflexum L. fil. in mice. The acetic acid-induced writhing test, formalin test, tail flick test and the tetradecanoylphorbol acetate (TPA)-induced ear inflammation model in mice were used to determine these effects. Our findings show that oral administration of all extracts tested from this species significantly inhibit acetic acid-induced writhing in mice. Only the methanol extract and chloroform fraction were significantly active in both phases of formalin-induced pain and in the tail flick assays, suggesting that they may have central analgesic properties. On the other hand, the topical treatment of methanol extract, butanol and chloroform fractions of this species significantly reduced the TPA-induced ear oedema. In conclusion, the results indicate analgesic and topical anti-inflammatory activities in mice for the Hypericum species studied.     

Antihepatotoxic activity of Swertia chirata on paracetamol and galactosamine induced hepatotoxicity in rats

The extracts of Swertia chirata were evaluated for antihepatotoxic activity using paracetamol and galactosamine models. The methanol extract of the whole plant was found active at a dose of 100 mg/kg i.p. On fractionating this extract into chloroform soluble and butanol soluble fractions, the activity was retained in the chloroform soluble fraction which was most active at a dose level of 25 mg/kg i.p. with overall protection of 81% and 78% against paracetamol and galactosamine, respectively. The butanol soluble fraction, rich in bitter secoiridoids, was devoid of significant activity. The protective effect observed against these two hepatotoxins which are different in their mechanisms of inducing hepatotoxicity, suggests broader and non-specific protection of the liver against these two toxins by non-bitter components of Swertia chirata.     

Hypericum grandifolium Choisy: A species native to Macaronesian Region with antidepressant effect

Aim of the study

Various species of Hypericum genus have been used in the Canary Islands as sedative, diuretic, vermifuge, wound healing, antihysteric and antidepressant agent. Studies have shown that methanol extract of Hypericum grandifolium Choisy is active in tetrabenazine-induced ptosis and forced swimming tests. In the current study, the aqueous, butanol and chloroform fractions obtained from the methanol extract as well as three sub-fractions derived from the chloroform fraction were evaluated for their central nervous effects in mice, particularly their antidepressant activity.

Materials and methods

The central nervous effect of different fractions and sub-fractions of Hypericum grandifolium was evaluated in mice using various behavioural models including locomotor and muscle relaxant activity, forced swimming test, effect on normal body temperature, barbiturate-induced sleep, tetrabenazine-induced syndrome and 5-hydroxytryptohan-induced head twitches and syndrome.

Results

We found that the butanol and chloroform fractions and all sub-fractions showed an antidepressant effect in the forced swimming test, the chloroform fraction being the most active. They produced no effects or only a slight depression of locomotor activity. Chloroform fraction significantly increased the pentobarbital-induced sleeping time, produced a slight but significant hypothermia and antagonized tetrabenazine-induced ptosis, whereas the butanol fraction produced a slight potentiation of 5-HTP-induced head twitches and syndrome.

Conclusions

The present results, together with previous pharmacological and phytochemical data, indicated that Hypericum grandifolium possess antidepressant-like effects in mice and that different constituents, such as the flavonoids and the benzophenone derivatives, could be responsible at least in part for the antidepressant effects observed for this species.     

Antihepatotoxic activity of Swertia chirata on carbon tetrachloride induced hepatotoxicity in rats

The methanol extract of Swertia chirata was evaluated for antihepatotoxic activity against carbon tetrachloride induced liver toxicity in experimental rats. The extract was found to be active and on fractionation into butanol soluble and chloroform soluble fractions, the activity was traced and found more profound in the chloroform soluble fraction. The butanol soluble bitter rich fraction showed marginal activity. The results based on biochemical estimations have been expressed statistically and are additionally supported by histopathological examination of the liver of experimental rats and pentobarbitone induced sleep time studies in mice.     

Antibacterial activity of Aristolochia paucinervis Pomel

Several fractions of the methanolic extract of the rhizome or the leaves of Aristolochia paucinervis Pomel were screened for antibacterial activity using the agar dilution method against fourteen reference bacterial strains. Only three fractions (defatted chloroformic rhizome fraction: APRC, rhizome ethyl acetate fraction: APRE and leaf chloroform fraction: APLC) showed an activity against at least one of the microorganisms tested. The minimum inhibitory concentration (MIC) determination showed that APRC was the most active against Clostridium perfringens, Clostridium difficile, Enterococcus faecalis, Micrococcus luteus and Bacillus subtilis. The high bacteriostatic activity of APRC was confirmed by its MIC determination against clinical strains of C. perfringens (n = 32), C. difficile (n = 31), and E. faecalis (n = 22). Results of this study suggest the potential interest of this highly active fraction and support the use of A. paucinervis Pomel in Moroccan traditional medicine to treat skin and soft-tissue infections, especially gas gangrene and intestinal diseases.     

Evaluation of antibacterial properties of some medicinal plants used in Iran

Forty-five species of 29 plant families used in the traditional medicine by Iranian people, showed antibacterial activities against one or more of the bacterial species: Bacillus cereus, Bacillus pumilus, Bordetella bronchiseptica, Escherichia coli, Klebsiella pneumoniae, Micrococcus luteus, Pseudomonas aeruginosa, Pseudomonas fluorescens, Serratia marcescens, Staphylococcus aureus and Staphylococcus epidermidis. No plant showed activity against Serratia marcescens; Bordetella bronchiseptica being the most susceptible species. All extracts showed the same activity 18 months later.     

Antimicrobial study of bark from five tree species.

The antimicrobial activities of chloroform, methanol and aqueous extracts of the bark of Gymnanthes lucida, Gliricidia sepium, Lysiloma divaricata, Lysiloma tergemina and Coccolaba cozumelensis were tested against S. lutea, E. coli, S. epidermidis, L. monocytogenes, S. choleraesuis, S. aureus, P. aeruginosa, B. pumillus, S. typhimurium, P. vulgaris, V. cholerae and C. albicans. It was found that methanol extracts of the two Lysiloma species and G. sepium had antimicrobial effects against S. epidermidis, S. aureus, P. aeruginosa, B. pumillus and V. cholerae at doses of 200 microg. The major inhibitory effect was observed with L. tergemina which showed a bacteriostatic effect on S. epidermidis at doses of 400 microg/mL.     

Antibacterial steroid alkaloids from the stem bark of Holarrhena pubescens

Holarrhena pubescens (syn. H. antidysenterica) (L.) WALL. stem bark was tested for antibacterial efficacy against Staphylococcus aureus, Staphylococcus epidermidis, Streptococcus faecalis, Bacillus subtilis, Escherichia coli and Pseudomonas aeruginosa using the microdilution broth method as well as the disc diffusion method. The crude methanolic extract was active against all tested bacteria. Further chemical fractionation indicated that the antibacterial activity was mainly associated with the alkaloids. The minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) were determined for the crude extract, the total alkaloids and the neutral fraction using microdilution broth method. The results were compared with reference antibiotics. The total alkaloids showed remarkable activity against S. aureus (MIC = 95 microg/ml).     

Antidiarrhoeal activity of the methanol extract of the barks of Xylocarpus moluccensis in castor oil- and magnesium sulphate-induced diarrhoea models in mice

The methanol (MeOH) extract of the barks of Xylocarpus moluccensis, and different fractions of this extract were studied for antidiarrhoeal activity using castor oil- and magnesium sulphate-induced diarrhoea models in mice. At the doses of 250 and 500 mg/kg, the MeOH extract showed significant antidiarrhoeal activity in both models. The EtOAc fraction (EAF) and the residual MeOH fraction (RMF) exhibited similar activity using a dose of 250 mg/kg in both models. No antidiarrhoeal activity was observed with the chloroform fraction (CHF) at the test doses. When tested for antibacterial effect, the MeOH extract displayed moderate inhibitory activity against Escherichia coli, Vibrio cholera, Staphylococcus aureus, Staphylococcus epidermis, Shigella dysentery, Staphylococcus pyogenes, Salmonella typhi, Pseudomonas aeruginosa and Enterobacter aerogenes. While the CHF inhibited the growth of Escherichia coli, Vibrio cholerae, Shigella dysenteriae, Shigella sonnei, Staphylococcus epidermis, Staphylococcus pyogenes and Pseudomonas aeruginosa, the EAF was active against all test organisms except Vibrio cholera and Staphylococcus epidermis. The RMF inhibited the growth of all the test organisms with moderate zone of inhibition. On the basis of these findings, it can be assumed that Xylocarpus moluccensis could be a potential source for novel 'lead' discovery for antidiarrhoeal drug development.     

In vitro activity of Rutaceae species against the trypomastigote form of Trypanosoma cruzi

The activity of crude plant extracts of nine species of Rutaceae against the trypomastigote form of Trypanosoma cruzi was evaluated at 4 mg/ml. Thirty-two crude extracts were tested and eight of them showed significant activity (>80%). The most active extract was obtained from the stems of Pilocarpus spicatus (97.3%). Fractionation of the active crude extracts provided 25 fractions which were tested against the trypomastigote form of T. cruzi at 2 mg/ml. Of these six showed significant activity (>80%). The most active fractions (100%) were obtained from the leaves of Almeidea coerulea (butanol fraction) and Conchocarpus inopinatus (dichloromethane fraction).     

Antibacterial potential from Indian Suregada angustifolia

Phytochemical analysis of the leaves from Indian Suregada angustifolia (Baill. ex Muell. Arg.) Airy Shaw (Euphorbiaceae) resulted in the isolation and identification of six known compounds, viz. friedelin, epi-friedelinol, n-octacosanol, alpha-amyrin, beta-sitosterol and beta-sitosterol-3-beta-D-glucopyranoside. Aqueous (room temperature, boiled and autoclaved) and various solvent (methanol, chloroform and hexane) extracts of leaves were tested against 12 human pathogenic bacteria by the agar well-diffusion method. Aqueous extracts did not express any activity. Antibacterial activity was recorded in the order of methanol, hexane and chloroform extracts. Maximum activity recorded against Staphylococcus aureus (skin infections) in methanol and hexane extracts and moderate activity recorded against diarrhoea causing bacteria, Vibrio vulnificus (hexane extract) and Vibrio cholerae (chloroform extract).     

连翘对金黄色葡萄球菌及表皮葡萄球菌的体外抗菌活性研究

[目的]观察连翘对金黄色葡萄球菌及表皮葡萄球菌的体外抗菌活性。[方法]用新的中药抑菌实验方法进行连翘对84株金葡菌和140株表皮葡萄球菌的体外抗菌活性的测定。[结果]连翘对金葡菌和表皮葡萄球菌能抑制50%菌株的最低细菌浓度(MIC50)均为0.122g/L,而能抑制90%菌株的最低抑菌浓度(MIC90)分别为0.98和0.244g/L。[结论]连翘对金黄色葡萄球菌和表皮葡萄球菌均有较好的体外抗菌效果。     

Screening for the antidepressant activity of some species of Hypericum from South Brazil

The crude methanol extracts of three species of the genus Hypericum (H. brasiliense, H. caprifoliatum and H. myrianthum) native to South Brazil were evaluated for the antidepressant activity according to the forced swimming test, a classical animal model for antidepressant drug screening. Among the species studied, only H. caprifoliatum showed activity. Thus, this plant was fractionated with solvents in increasing polarity (petroleum ether; petroleum ether: chloroform (1:1); chloroform and methanol). The petroleum ether fraction was the only one which demonstrated antidepressant activity at a dose of 270 mg/kg/day (i.p.). The chemical analyses showed that this fraction is rich in phenolic compounds, mainly of the phloroglucinol type.