Relaxant effect of aqueous extract of Cistus ladaniferus on rodent intestinal contractions

The effects of the aqueous extract of Cistus ladaniferus leaves and stems were studied on the rodent isolated jejunum. The extract produced a reversible concentration dose-dependent (0.1-3 mg/ml) inhibition of the spontaneous motility of the rabbit jejunum. The inhibitory effects of the extract were not affected by pretreatment with the inhibitors of the alpha and beta adrenergic receptors yohimbine, prazosin or propranolol. The extract also inhibited K(+)-induced contractions in rabbit and rat jejunum at a similar concentration range. This result suggests that the antispasmodic action of the extract is mediated through calcium channel blockade. The results confirm the traditional use of C. ladaniferus in treating intestinal ache.     

Antimicrobial activity of the Derris elliptica, Derris indica and Derris trifoliata extractives

Various parts of Derris elliptica, Derris indica and Derris trifoliata on fractionation with a number of solvents (petrol, dichloromethane, ethyl acetate, butanol and methanol) gave fractions which demonstrated a varied level of broad spectrum antibacterial activity. Good activity was exhibited by the methanol fractions of the leaves and root heart-wood, petrol, butanol and methanol fractions of the root bark of D. indica and petrol and ethyl acetate fractions of D. trifoliata. None of the plants showed antifungal activity.     

Antimicrobial activity of the Maniltoa schefferi extracts

All fractions of Maniltoa schefferi exhibited a broad spectrum of antibacterial activity. Good activity was demonstrated by the petrol and dichloromethane fractions of seed pods, seeds with coat and by methanol fractions of stem heartwood, root bark, root heartwood and stem bark whose butanol fraction was equally good. None of the fractions showed any antifungal activity.     

Evaluation of antioxidant effect of extracts of Symphyopappus casarettoi

The ethanolic extract of Symphyopappus casarettoi syn. Eupatorium casarettoi was partionated in hexanic, chloroformic and methanolic fractions. Extract and fractions were tested for their antioxidant activity in vitro and ex vivo assays. The methanolic fraction showed a higher antioxidant potential compared to the others fractions, which was correlated with its total phenol content. In addition, the ethanolic extract and the methanolic fraction attenuated ex vivo iron-induced cell death, quantified by lactate dehydrogenase leakage, and effectively protected against lipid damage induced by iron. These findings suggest that the ethanolic extract of S. casarettoi inflorescence and its methanolic fraction have in vitro and ex vivo antioxidant properties.     

Larvicidal activity of saponin containing extracts and fractions of fruit mesocarp of Balanites aegyptiaca

Chloroform, ethyl acetate, butanol and methanol extracts of fruit mesocarp of Balanites aegyptiaca and five fractions from the methanol extract were tested against the Aedes aegypti mosquito larvae. All extracts showed larvicidal effects however the highest larval mortality was found in methanol extract. One fraction obtained from the silica gel column chromatography of the latter was found most effective for larval mortality. This fraction also interfered with adult emergence. A concentration of 0.0014% (w/v) of this active fraction showed inhibition of the 50% of the test larval population from emerging adults (EC(50)). The analysis of total saponin content of these tested extracts and fractions revealed a strong correlation between saponin content and larval mortality.     

Antibacterial activities of some mosses including Hylocomium splendens from South Western British Columbia

The antibacterial activity of methanol extracts of ten moss species and fractions prepared from 80% methanol extract of Hylocomium splendens were evaluated by disk diffusion method. Nine moss species showed antibacterial activity against Gram (+) bacteria, in particular H. splendens and its ethyl acetate fractions showed stronger activity. Enhancement of antibacterial activity against Staphylococci by UV-A light irradiation was demonstrated in the extracts of Bartramia pomiformis, Ceratodon purpureus and Neckera douglasii.     

Isorhynchophylline: A plant alkaloid with therapeutic potential for cardiovascular and central nervous system diseases

Uncaria species (Gouteng in Chinese) have been used as a plant medicine to treat ailments of cardiovascular and central nervous systems. As the main alkaloid constituent of Uncaria species, isorhynchophylline has drawn extensive attention toward antihypertensive and neuroprotective activities in recent years. Isorhynchophylline mainly acts on cardiovascular and central nervous systems diseases including hypertension, brachycardia, arrhythmia, and sedation, vascular dementia, and amnesia. Isorhynchophylline also has effects on anticoagulation, inhibition vascular smooth muscle cell apoptosis and proliferation, anti-multidrug resistant of lung cells, anti-endotoxemic, and antispasmodic. The active mechanisms are related to modulation on calcium ion channel, protection neural and neuroglial cells against β-amyloid(25-35)-induced neurotoxicity and via inducing autophagy. As a candidate drug of several cardiovascular and central nervous systems diseases, isorhynchophylline will attract scientists to pursue the potential related pharmacological effects and its mechanism with new technologies. But relatively few clinical application of isorhynchophylline has been conducted on its pharmacological activities. It requires more in vivo validations and further investigations of antihypertensive and neuroprotective mechanisms of isorhynchophylline.     

Antibacterial effect of Dryopteris crassirhizoma against methicillin-resistant Staphylococcus aureus

Methanol extract and its fractions (hexane, EtOAc, n-BuOH, and H2O) of Dryopteris crassirhizoma were investigated for antibacterial activity against methicillin-resistant Staphylococcus aureus. The hexane fraction showed a good antibacterial activity against all tested strains.     

Free radical scavenging activity of different extracts and some constituents from the leaves of Ligustrum vulgare and L. delavayanum

The free radical scavenging activity of the water infusions, different organic solvent extracts and some constituents from Ligustrum vulgare and Ligustrum delavayanum leaves was assessed with the aid of DPPH radical. Among the samples screened, water infusions had the strongest free radical scavenging capacity. From the tested compounds scavenging active flavonoid aglycones are present in the most active chloroform fractions from both leaves samples.     

Antioxidative and radical scavenging effects of phenolics from Vicia sativum

An acetone extract of Vicia sativum seeds and fractions, comprising low molecular-weight phenolics and tannins, displayed good antioxidant activity.     

Study on the antimicrobial activity of Hymatanthus sucuba

The antimicrobial activity of Hyamatantus sucuba roots methanol extract, fractions prepared from this extract (n-hexane, CHCl(3), EtOAc, and n-butanol) and some isolated compounds were evaluated against some Gram(+) and Gram(-) bacteria and yeasts.     

Antioxidant activity and total phenolic content in Cirsium five species from north-east region of Poland

Methanolic extracts from inflorescences and leaves of five Cirsium species: C. arvense, C. oleraceum, C. palustre, C. rivulare and C. vulgare and CHCl3, Et2O, EtOAc, n-BuOH fractions obtained from those extracts were investigated for their antioxidant activity. The antioxidant activity measurement, expressed as Total Antioxidant Status, ranged from 0.98 to 2.71 mM/l. The total phenolic content of the samples varied from 12 to 804 mg/g. There was a positive correlation between the total phenolic content and antioxidant activity for MeOH extracts and EtOAc fractions (R2=0.95, 0.8 respectively).     

Inhibitory effect of a bioactivity-guided fraction from Rheum undulatum on the acid production of Streptococcus mutans biofilms at sub-MIC levels

Rheum undulatum root has been used traditionally in Korea for the treatment of dental diseases. The purpose of this study was to separate a fraction from R. undulatum showing anti-acid production activity against Streptococcus mutans biofilms and identify the main components in that fraction. Methanol extract of R. undulatum root and its fractions were prepared. To select a fraction exhibiting anti-acid production activity, suspension glycolytic pH-drop assay was performed. Among the fractions tested, dichloromethane fraction exhibited the strongest activity in a dose-dependent manner. To examine the effect of the selected fraction on the anti-acid production of S. mutans biofilms, 74 h old S. mutans biofilms were used. The selected fraction reduced the initial rate of acid production of S. mutans biofilms at sub-minimum inhibitory concentration (MIC) levels. HPLC qualitative analysis of the selected fraction indicated that the presence of anthraquinone derivatives, such as aloe-emodin, emodin, chrysophanol and physcion, as main components.     

Antioxidant activity of Agaricus blazei

The ethanolic extract of Agaricus blazei and ethyl acetate and hydroalcoholic fractions were evaluated for their antioxidant activity.     

Effects of fertilisation on phosphorus pools in the volcanic soil of a managed tropical forest

Acacia koa forests benefit from phosphorus fertilisation, but it is unknown if fertilisation is a short or long term effect on P availability. Past research suggests that P cycling in soils with high P sorption capacity, such as Andisols, was through organic pathways. We studied leaf P and soil P fractions in a tropical forest Andisol for 3 years after fertilisation with triple super phosphate. Leaf P concentration and labile P remained high after fertilisation. Fertilisation had increased all the inorganic P fractions over the length of the study, while organic P fractions had not. The results suggested that the organic P fractions had a reduced role as a source of labile P after fertilisation. The size and dynamics of the sodium hydroxide- and hydrochloric acid-extractable P pools would suggest that either pool could be major sources of labile P. Because of the high level of poorly crystalline minerals in Andisols (allophone and imogolite), it would be expected that applied P would quickly lead to strong P sorption onto mineral surfaces and thus a rapid decline in P availability. We propose that the high organic matter present in these soils had masked some of the Al and Fe sorption sites, which allowed the sorption and desorption when large amounts of addition P were applied.     

Evaluation of the biological activity of the molluscicidal fraction of Solanum sisymbriifolium against non target organisms

The evaluation of the biocidal activity of the fruit of Solanum sisymbriifolium involving non target organisms such as aquatic insects, fish and snails lead to the isolation of the steroidal alkaloids, solamargine and β-solamarine, from the active fractions. The fractions A3 and C, with biological activity against fish, snail and aquatic insect and larvae, are able to affect the good functioning of ecosystem found on alimentary chain. The fraction B seems to be less toxic to fish and aquatic insect and larvae. The fraction B could thus be used as molluscicide in the future.     

Antidiarrhoeal activity of Cyperus rotundus

The methanol extract of Cyperus rotundus rhizome, given orally at the doses of 250 and 500 mg/kg b.w., showed significant antidiarrhoeal activity in castor oil induced diarrhoea in mice. Among the fractions, tested at 250 mg/kg, the petroleum ether fraction (PEF) and residual methanol fraction (RMF) were found to retain the activity, the latter being more active as compared to the control. The ethyl acetate fraction (EAF) did not show any antidiarrhoeal activity.     

Antimicrobial activity of Diospyros anisandra

Leaves, root and stem bark of Diospyros anisandra were screened against two strains of Mycobacterium tuberculosis, one resistant and one susceptible to antibiotics, using the microplate Alamar blue assay test. The lypophylic fractions of the root and bark showed significant inhibitory activity against both strains, with the hexane fraction of the bark showing the strongest activity (MIC 6.25 microg/ml) against the resistant strain and a significant antimicrobial activity against Staphylococcus aureus, Bacillus subtilis, Candida albicans, Aspergillus niger, and Colletotrichum gloeosporioides. The bioassay-guided purification of the bioactive hexane fraction resulted in the isolation and identification of the naphthoquinone plumbagin as one of the metabolites responsible for the biological activity.     

Molluscicidal activity of Aglaia duperreana and the constituents of its twigs and leaves

The methanol (MeOH) extract of the twigs and leaves of Aglaia duperreana was investigated for its molluscicidal activity against Pomacea canaliculata. The extract was found to exhibit significant molluscicidal activity. The ethyl acetate soluble fraction of the extract showed the most potent molluscicidal activity among different solvent fractions. The bioactivity-guided chemical investigation of the ethyl acetate soluble fraction led to a new triterpenoid along with 15 known compounds. Their structures were elucidated by spectroscopic methods, including one- and two-dimensional nuclear magnetic resonance techniques as well as mass spectroscopic analysis. The molluscicidal activities of compounds 2-16 against P. canaliculata were also investigated. Naringenin trimethyl ether showed significant molluscicidal activity with a median lethal concentration (LC(50)) of 3.9 μg/mL, which was indicated higher potency than the positive control, tea saponin (LC(50)=4.5 μg/mL).