Anthelmintic screening of Zimbabwean plants traditionally used against schistosomiasis

Extracts of 23 plant species used popularly against schistosomiasis in Zimbabwe were screened for their anthelmintic effect. Schistosomules of the trematode Schistosoma mansoni and cysticercoids of the cestode Hymenolepis diminuta were studied in vitro. The material consisted of 58 plant extracts, of which 37 killed the newly excysted cysticercoids within an hour, when incubated in a culture medium. Lethal concentrations varied from 0.8 to 103 mg/ml. All plant extracts showed activity against the tapeworms after 24 h. Ten of the best extracts were also tested against schistosomules. Five of these extracts showed activity. Lethal concentrations varied from 0.6 to 33.8 mg/ml of dry plant material. Extracts of stem and root from Abrus precatorius (Fabaceae), of root bark and leaves from Ozoroa insignis (Anacardiaceae) and of root bark from Zizyphus mucronata (Rhamnaceae) gave the best results against tapeworms. The best results against schistosomules were obtained with stem and root extracts from Abrus precatorius (Fabaceae) and stem bark from Elephantorrhiza goetzei (Mimosaceae). Although the activity of root and root bark extracts commonly used in traditional medicine was verified in this study, our results showed that also extracts from leaf and stem can be effective anthelmintics.     

Screening of selected Indian medicinal plants for acetylcholinesterase inhibitory activity

Seventy-six plant extracts including methanolic and successive water extracts from 37 Indian medicinal plants were investigated for acetylcholinesterase (AChE) inhibitory activity (in vitro). Results indicated that methanolic extracts to be more active than water extracts. The potent AChE inhibiting methanolic plant extracts included Withania somnifera (root), Semecarpus anacardium (stem bark), Embelia ribes (Root), Tinospora cordifolia (stem), Ficus religiosa (stem bark) and Nardostachys jatamansi (rhizome). The IC(50) values obtained for these extracts were 33.38, 16.74, 23.04, 38.36, 73.69 and 47.21mug/ml, respectively. These results partly substantiate the traditional use of these herbs for improvement of cognition.     

In vitro antioxidant and antimicrobial activity of extracts from Morus alba L. leaves, stems and fruits

In this study, the aqueous and ethanolic extracts (leaves, stems and fruits) from Morus alba L., a traditional Chinese medicine, were evaluated for their antioxidant and antimicrobial properties. Ethanolic extracts showed higher contents of both total phenolics and flavonoids than aqueous extracts. The total phenolic content was in the order of: leaf extracts > fruit extracts > stem extracts, whereas the total flavonoids was: leaf extracts > stem extracts > fruit extracts. Using DPPH assays, the concentrations providing 50% inhibition (IC(50)) values of aqueous extracts from leaves, stems and fruits were 7.11 ± 1.45 mg/ml, 86.78 ± 3.21 mg/ml and 14.38 ± 2.83 mg/ml, respectively, whereas the IC(50) values of ethanolic extracts were 3.11 ± 0.86 mg/ml, 14.62 ± 2.45 mg/ml and 12.42 ± 2.76 mg/ml, respectively. In sum, the antioxidant activities of ethanolic extracts from M. alba L. were stronger than the aqueous extracts, and in the order of: leaf extracts > fruit extracts > stem extracts. The ethanolic extracts exhibited moderate antimicrobial activities, whereas the aqueous extracts showed poor antimicrobial properties in our test system. This study validated the medicinal potential of M. alba L.     

Evaluation of antifungal activity of extracts of two Cameroonian rutaceae: Zanthoxylum leprieurii Guill. et Perr. and Zanthoxylum xanthoxyloides Waterm

Aqueous-ethanol 90% extracts of leaves, roots and stem barks of Zanthoxylum leprieurii and Zanthoxylum xanthoxyloides were examined for their antifungal properties against nine fungi by dilution methods on a solid medium and in a liquid medium. Our results indicate that these extracts, to varying extents, inhibit the in vitro growth of Candida albicans, Cryptococcus neoformans and seven filamentous fungi tested. Only the extracts obtained from the roots and stem barks of Z. xanthoxyloides showed antifungal activity on the germs studied, with minimal inhibitory concentration varying, respectively, from 0.5 to 1 mg/ml for the roots and from 0.125 to 1 mg/ml for the stem barks.     

Anti-bacterial activity of some Brazilian medicinal plants

Extracts from various organs of 25 plants of Brazilian traditional medicine were assayed with respect to their anti-bacterial activities against Escherichia coli, a susceptible strain of Staphylococcus aureus and two resistant strains of Staphylococcus aureus harbouring the efflux pumps NorA and MsrA. Amongst the 49 extracts studied, 14 presented anti-bacterial activity against Staphylococcus aureus, including the ethanolic extracts from the rhizome of Jatropha elliptica, from the stem barks of Schinus terebinthifolius and Erythrina mulungu, from the stems and leaves of Caesalpinia pyramidalis and Serjania lethalis, and from the stem bark and leaves of Lafoensia pacari. The classes of compounds present in the active extracts were determined as a preliminary step towards their bioactivity-guided separation. No extracts were active against Escherichia coli.     

Down-modulation of nitric oxide production in murine macrophages treated with crude plant extracts from the Brazilian Cerrado

Several plant species from the Cerrado biome in Brazil are popularly used as herbal medicines for its reputed analgesic, anti-acid, anti-microbial, anti-inflammatory and anti-tumoral properties, among others. It has been reported that some plant extracts interfere in the production of nitric oxide (NO), an important inflammatory mediator. In the present study, we investigated the effect of hexanic and ethanolic extracts from three plant species on NO production by LPS/IFN-gamma-activated J774 macrophages based on traditional use. The cytotoxic effect of the crude extracts was determined by the thiazolyl blue test (MTT) to measure cell viability. Serjania lethalis stem extracts and Cupania vernalis leaf extracts significantly inhibited NO production, while extracts from Casearia sylvestris var. lingua were inactive or showed low activity on NO production, or were very cytotoxic. The ethanolic stem bark and leaf extracts of Serjania lethalis and Cupania vernalis, respectively, almost completely inhibited the production of NO by J774 macrophages. It can be concluded that the selected extracts are potential sources of active compounds that might be used as anti-inflammatory agents.     

Anti-inflammatory activity of methanolic extracts from Ventilago harmandiana Pierre

Methanolic extracts from the heart wood, stem bark, and stem wood of Ventilago harmandiana Pierre (Family Rhamnaceae) were assessed for anti-inflammatory effects using both acute and chronic inflammatory models. Analgesic and antipyretic activities of the extracts were also evaluated. It was found that all extracts possessed strong inhibitory effects on the acute phase of inflammation as seen in ethyl phenylpropiolate (EPP)- and arachidonic acid (AA)-induced ear edema as well as in carrageenin-induced paw edema in rats. The extracts elicited only weak inhibitory activity on cotton pellet-induced granuloma formation, a subchronic inflammatory model. In the analgesic test, all extracts exerted pronounced inhibitory activity in acetic acid-induced writhing response but showed only weak effects in the tail-flick test. The extracts also showed excellent antipyretic activity on yeast-induced hyperthermia in rats.     

Evaluation of antifungal activity of extracts of two Cameroonian Rutaceae: Zanthoxylum leprieurii Guill. et Perr. and Zanthoxylum xanthoxyloides Waterm.

Aqueous-ethanol 90% extracts of leaves, roots and stem barks of Zanthoxylum leprieurii and Zanthoxylum xanthoxyloides were examined for their antifungal properties against nine fungi by dilution methods on a solid medium and in a liquid medium. Our results indicate that these extracts, to varying extents, inhibit the in vitro growth of Candida albicans, Cryptococcus neoformans and seven filamentous fungi tested. Only the extracts obtained from the roots and stem barks of Z. xanthoxyloides showed antifungal activity on the germs studied, with minimal inhibitory concentration varying, respectively, from 0.5 to 1 mg/ml for the roots and from 0.125 to 1 mg/ml for the stem barks.     

Assessment of the phytochemical and antitrypanosomal properties of some extracts of leaves, stem and root bark of Landolphia sp., P. Beauv

INTRODUCTION/JUSTIFICATION: There is urgent need to source for alternative chemotherapy against trypanosmosis, a disease of major importance in human and economic animals. MATERIALS AND METHODS: Therefore, petroleum ether, chloroform, methanol and aqueous extracts sequentially obtained from the leaves, stem and root barks of Landolphia uniflora were evaluated for their in vitro and in vivo antitrypanosomal activities against Trypanosoma brucei brucei, as well as their phytochemical constituents. RESULTS: Steroids and triterpenes, resins, tannins, saponins and flavonosides were detected in almost all the extracts, but alkaloid was absent in methanol extract of the stem and stem, as well as the chloroform extract of the root bark. In vitro, all extracts of the roots displayed significant antitrypanosomal activity, while only the chloroform extracts of the leaves and stem bark showed activity at both test concentrations (4 and 2 mg/ml). However, under in vivo condition, the methanol extracts showed the greatest activity, eliminating parasitaemia within the 10 days treatment period and prolonging survival period at 200 and 300 mg/kg body weight intramuscular doses. CONCLUSION: These results suggest that Landolphia uniflora could be useful in the management of trypanosomiasis.     

Antioxidant activity of Siamese neem tree (VP1209)

Leaves, fruits, flowers and stem bark extracts from the Siamese neem tree (Azadirachta indica A. Juss var. siamensis Valeton, Meliaceae) were assessed for antioxidant activity in vitro using the 1,1-diphenyl-2-picryl hydrazyl (DPPH) scavenging assay, total antioxidant activity and inhibition of lipid peroxidation in Chago K1 cancer cell culture by the thiobarbituric acid reactive substances (TBARS) method. The results showed that leaf aqueous extract, flower and stem bark ethanol extracts exhibited higher free radical scavenging effect on the DPPH assay with 50% scavenging activity at 26.5, 27.9 and 30.6 microg/ml, respectively. The total antioxidant activity of these extracts was found to be 0.959, 0.988 and 1.064 mM of standard trolox, respectively. At 100 microg/ml, the flower ethanol and leaf aqueous extracts significantly decreased malondialdehyde (MDA) levels (46.0 and 50.6%, respectively) by the TBARS method. The results suggest that extracts from leaf, flower and stem bark of the Siamese neem tree have strong antioxidant potential. This report supports the ethnomedical use of young leaves and flowers of this plant as a vegetable bitter tonic to promote good health.     

罗汉果茎叶提取物的血清药物化学研究

目的：对罗汉果茎叶提取物的入血成分进行分析研究,进一步诠释其药效物质基础。方法：通过罗汉果茎叶提取物、含药血清和空白血清的HPLC指纹图谱比对分析,探讨罗汉果茎叶提取物的人血成分。结果：在罗汉果茎叶提取物指纹图谱的15个指纹峰中,有7个指纹峰与含药血清的图谱一致,其中1个指纹峰被指认为山柰苷。结论：山柰苷为罗汉果茎叶提取物的有效成分,其他6个指纹峰成分也可能为有效成分。     

Toxicological studies on stem bark, leaf and seed kernel of yellow oleander (Thevetia peruviana)

A comparative study of the toxic effects of extracts from stem bark, leaf and seed kernel of yellow oleander (Thevetia peruviana) in albino rats was carried out. Male and female albino rats weighing 150-200 g were administered crude aqueous extracts of stem bark, leaf and seed kernel of the plant by intraperitoneal injection or exposed to baits prepared with the dry extracts of the plant parts. The control groups either received distilled water by injection, or were fed non-poisoned baits. Extracts from all the plant parts were toxic, and produced marked poisoning symptoms that culminated in death. Poisoning symptoms manifested earlier (10 min after treatment) in rats administered aqueous kernel extracts intraperitoneally as against 45 min to several hours in rats poisoned by ingestion of toxicant. Poisoning symptoms indicated serious cardiac, neuromotor and mental malfunctioning, and manifested as tachycardia, arrhythmia, paralysis, ataxia and disorientation. The lethal dose was lowest (507 mg/kg) with the concentrated aqueous kernel extract (CAKE), and highest (5700 mg/kg) with the bait formulated using 40% of the kernel meal - FKM(B). Rats treated by injection with aqueous kernel extract (AKE) died faster within 10 h, than those with the aqueous leaf or stem bark extracts that died after 260 h. No mortality or abnormal behavioural changes were observed among animals in the control groups.     

Antimicrobial, antioxidant, antitumour-promoting and cytotoxic activities of different plant part extracts of Garcinia atroviridis griff. ex T. anders

Crude extracts (methanol) of various parts, viz. the leaves, fruits, roots, stem and trunk bark, of Garcinia atroviridis were screened for antimicrobial, cytotoxic, brine shrimp toxic, antitumour-promoting and antioxidant activities. The crude extracts exhibited predominantly antibacterial activity with the root extract showing the strongest inhibition against the test bacteria at a minimum inhibitory dose (MID) of 15.6 microg/disc. Although all the extracts failed to inhibit the growth of most of the test fungi, significant antifungal activity against Cladosporium herbarum was exhibited by most notably the fruit (MID: 100 microg), and the leaf (MID: 400 microg) extracts. None of the extracts were significantly cytotoxic, and lethal towards brine shrimps. The root, leaf, trunk and stem bark extracts (except for the fruits) showed strong antioxidant activity exceeding that of the standard antioxidant, alpha-tocopherol. Antitumour-promoting activity (>95% inhibition) was shown by the fruit, leaf, stem and trunk bark extracts.     

Antitumor, antioxidant and antimicrobial activities of Bersama engleriana (Melianthaceae)

The aim of this study was to evaluate the antitumor, antioxidant and antimicrobial activities as well as the phytochemical composition and the acute toxicity of the methanolic extracts from the roots (BER), stem bark (BEB), leaves (BEL) and wood (BEW) of Bersama engleriana. The crown gall tumor and DPPH radical scavenging assays were used to detect respectively the antitumoral and oxidant activities. Agar diffusion and liquid dilution were used for antimicrobial tests and the phytochemical assays were conducted according to Harbone methods. The single-dose oral toxicity test was performed in accordance with the OPPTS 870.1100 and OECD 401 guidelines. The phytochemical tests indicated the presence of flavonoids, phenols, triterpenes and anthraquinones in all extracts. Pronounced tumor reducing activity was observed with the extracts from the roots (69.32%) and leaves (65.42%). The DPPH scavenging activity showed that the extract from the leaves was the most active with 93.71% inhibition rate at the 1000 microg/ml. The results of antimicrobial activity showed that all tested extracts were active against all tested microbial species, including Gram-positive, and negative bacteria, the two Candida species and mycobacteria. The MIC values obtained ranged from 9.76 to 156.25 microg/ml. Under the conditions of the studied toxicity, all extracts were found to be non-toxic. The overall results of this study indicates that the extracts from the roots, stem bark, leaves and wood have interesting antioxidant properties and represent a potential source of medicine for the treatment of infectious diseases and cancer.     

Chemical constituents and antimicrobial activity of medicinal plants from Ghana: Cassia sieberiana, Haematostaphis barteri, Mitragyna inermis and Pseudocedrela kotschyi

The antimicrobial activity of the sequential n-hexane, acetone and 50% aqueous methanol extracts of leaves, stem bark and roots of four species of medicinal plants, Cassia sieberiana DC. (Leguminosae), Haematostaphis barteri Hook. f. (Anacardiaceae), Mitragyna inermis (Willd.) O. Kuntze (Rubiaceae) and Pseudocedrela kotschyi (Schweinf.) Harms (Meliaceae), from Ghana were tested against Bacillus subtilis, Pseudomonas syringae and Cladosporium herbarum using TLC direct-autobiographic methods. Extracts from leaves, stem bark and roots of the four species gave a positive result against at least one test organism. Twelve of the 36 extracts were active against B. subtilis, four extracts were active against P. syringae and six were active against C. herbarum. Preliminary chemical analysis revealed the presence of flavonoids, stilbenes and alkaloids. This is the first report of a stilbene from the Anacardiaceae.     

Preliminary screening of some traditional zulu medicinal plants for anti-inflammatory and anti-microbial activities

Aqueous and methanolic extracts from different parts of nine traditional Zulu medicinal plants, of the Vitaceae from KwaZulu-Natal, South Africa were evaluated for therapeutic potential as anti-inflammatory and anti-microbial agents. Of the twenty-nine crude extracts assayed for prostaglandin synthesis inhibitors, only five methanolic extracts of Cyphostemma natalitium-root, Rhoicissus digitata-leaf, R. rhomboidea-root, R. tomentosa-leaf/stem and R. tridentata-root showed significant inhibition of cyclo-oxygenase (COX-1). The extracts of R. digitata-leaf and of R. rhomboidea-root exhibited the highest inhibition of prostaglandin synthesis with 53 and 56%, respectively. The results suggest that Rhoicissus digitata leaves and of Rhoicissus rhomboidea roots may have the potential to be used as anti-inflammatory agents. All the screened plant extracts showed some degrees of anti-microbial activity against gram-positive and gram-negative microorganisms. The methanolic extracts of C. natalitium-stem and root, R. rhomboidea-root, and R. tomentosa-leaf/stem, showed different anti-microbial activities against almost all micro-organisms tested. Generally, these plant extracts inhibited the gram-positive micro-organisms more than the gram-negative ones. Several plant extracts inhibited the growth of Candida albicans while only one plant extract showed inhibitory activity against Saccharomyces cerevisiae. All the plant extracts which demonstrated good anti-inflammatory activities also showed better inhibitory activity against Candida albicans.     

Antimicrobial potential of two different Hypericum species available in India

The antimicrobial activity of extracts of the leaves and stems of two different varieties of Hypericum was evaluated by the disc diffusion method. Petroleum ether, acetone, chloroform and methanol extracts of Hypericum mysorense and Hypericum patulum stems and leaves were investigated for their antimicrobial activity against six different strains of bacteria and fungi by the zone of inhibition method (ZIM). The results showed that both the stem and leaf extracts of both species have a very broad spectrum of antibacterial activity. The petroleum ether and acetone extract of the leaves and stems of H. mysorense did not show antifungal effects against any of the six fungal organisms tested but other extracts showed a potential antifungal effect which was comparable to that of griseofulvin, the standard antifungal agent. Thus these results demonstrate that the leaf and stem extracts of both the Hypericum species have a very broad spectrum of activity and suggest that they may be useful in the treatment of various microbial infections.     

Anticonvulsant activity of root and stem extracts of Calliandra portoricensis

A comparative study of the anticonvulsant properties of root and stem extracts of Calliandra portoricensis was carried out in mice. The convulsion models were pentylenetetrazole- and electroshock-induced convulsions. The results showed that the aqueous extracts of both root and stem possess anticonvulsant activity when given intraperitoneally. An alkaloidal extract did not show any anticonvulsant action up to 316 mg/kg i.p.     

Effects of root and stem extracts of Asparagus cochinchinensis on biochemical indicators related to aging in the brain and liver of mice

Asparagus cochinchinensis is a traditional Chinese medicine used for treating lung and spleen-related diseases. In this study, we compared the medicinal effects of A. cochinchinensis root and stem extracts on the activity of superoxide dismutase (SOD), the content of malonaldehyde (MDA) and total protein content in the brain, liver and plasma of mice. Polysaccharides and aqueous extracts of the roots significantly increased the spleen index and the SOD activity but reduced the MDA content and slowed down the aging process. In contrast, feeding with the stem extracts significantly reduced the SOD activity and increased the MDA accumulation in the brain and liver of mice, suggesting that the stem extracts may not be appropriate for treating aging-related diseases.     

The in vitro biological activity of selected South African Commiphora species

Ten South African Commiphora (Burseraceae) species were investigated to validate their use in traditional healing rites. The leaf and stem extracts of each species were analysed for the anti-oxidant (ABTS and DPPH assays), antimicrobial (MIC and death kinetic assays), anti-inflammatory (5-LOX assay), anticancer (SRB assay) properties, as well as the cytotoxic effects (tetrazolium-based assay). The best anti-oxidant activity (ABTS assay) was observed for the stem extracts of Commiphora tenuipetiolata IC(50)=5.10 microg/ml), Commiphora neglecta (IC(50)=7.28 microg/ml) and Commiphora mollis (IC(50)=8.82 microg/ml). Extracts generally exhibited poor anti-oxidant activity in the DPPH assay, with the exception of Commiphora schimperi (stem), Commiphora neglecta (stem), Commiphora tenuipetiolata (stem and leaf), and Commiphora edulis (stem), with IC(50) values ranging between 7.31 and 10.81 microg/ml. The stem extracts exhibited moderate to good 5-LOX inhibitory activity with Commiphora pyracanthoides (stem) displaying the greatest inhibitory effect (IC(50)=27.86+/-4.45 microg/ml). For the antimicrobial (MIC) assay, a greater selectivity was exhibited by the extracts against the Gram-positive bacteria (0.01-8.00 mg/ml) and the yeasts (0.25-8.00 mg/ml) than against the Gram-negative bacteria (1.00-8.00 mg/ml). Using death kinetic studies (time-kill studies), the rate at which Commiphora marlothii (stem) kills Staphylococcus aureus over a 24h period was determined. Mostly, a concentration-dependent antibacterial activity was observed beginning after ca. 30 min. All concentrations exhibited antibacterial activity, with complete bactericidal effect achieved by the 24(th) hour. The most active Commiphora species against the HT-29 cells (SRB anticancer assay) were Commiphora glandulosa (leaf and stem) and Commiphora marlothii (leaf). The MCF-7 cells (SRB anticancer assay) exhibited the highest sensitivity to indigenous Commiphora species, with Commiphora edulis (leaf and stem), Commiphora glandulosa (leaf and stem), Commiphora marlothii (leaf), Commiphora pyracanthoides (leaf and stem), Commiphora schimperi (stem), and Commiphora viminea (stem) all possessing a percentage inhibition greater than 80% at 100 microg/ml. Commiphora glandulosa (leaf and stem) and Commiphora pyracanthoides (leaf and stem) were the two most active species against the SF-268 cells (SRB anticancer assay), with IC(50) values ranging between 68.55+/-2.01 and 71.45+/-1.24 microg/ml. The majority of the Commiphora extracts were largely non-cytotoxic against Graham human kidney epithelial cells when investigated in the MTT assay.