In vitro antifungal activities of longan (Dimocarpus longan Lour.) seed extract

Longan, Dimocarpus longan Lour., contains polyphenolic compounds which exhibit several pharmacological properties. This study aims to evaluate antifungal activities of longan fruit extract in comparison to its active compounds. The results showed that longan seed exhibited antifungal activity against the opportunistic yeasts (Candida species and Cryptococcus neoformans). In contrast, longan pulp and whole fruit did not demonstrate any inhibitory effects. Ellagic acid showed the most potent antifungal activity followed by corilagin and gallic acid, respectively. Ellagic acid inhibited Candida parapsilosis and C. neoformans more effectively than Candida krusei and also some Candida albicans clinical strains. Baidam cultivar possessed higher antifungal activity (MIC=500-4000 μg/ml) as it contained higher contents of ellagic acid and gallic acid than Edor (MIC=1000-8000 μg/ml). For antibacterial activity, only corilagin and gallic acid possessed weak to moderate inhibitory effects against Staphylococcus aureus and Streptococcus mutans, respectively. Longan seed was then applied in the oral care products. Longan effervescent granule (5% extract) significantly reduced adhesion of C. albicans to acrylic strips. Mouthwash containing 0.5% extract exhibited good antifungal activity compared to a commercial product. These findings indicated that longan seed extract and its polyphenolic compounds can be used as an antifungal agent in oral care products for the treatment of opportunistic yeast infection.     

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.     

Effects of a bio-assay guided fraction from Polygonum cuspidatum root on the viability,acid production and glucosyltranferase of mutans streptococci

Polygonum cuspidatum root has been traditionally used for the treatment of dental diseases in Korea. The purpose of this study was to evaluate effects of P. cuspidatum root on the development of dental caries, especially its effects against bacterial viability and caries-inducing factors of Strptococcus mutans and Strptococcus sobrinus. Among methanol extract of P. cuspidatum root and its fraction tested, ethyl acetate fraction, composed of polydatin, resveratrol, anthraglycoside B, and emodin, showed inhibitory effects on glycolytic acid production and glucosyltransferase activity of S. mutans and S. sobrinus in addition to antibacterial activities.     

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.     

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).     

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.     

Evaluation of antimicrobial activity of Cleome viscosa and Gmelina asiatica

The ethanolic extracts of the leaves and flowers of Cleome viscosa and roots of Gmelina asiatica were tested for antimicrobial activity. The two plants exhibited a broad spectrum of antimicrobial activity, particularly significative against Escherichia coli , Proteus vulgaris and Pseudomonas aeruginosa. The leaf extract of C. viscosa showed moderate activity against pathogenic fungi.     

Antioxidant, icthyotoxicity and brine shrimp lethality tests of Magonia glabrata

The ethanolic extract of the fruit bark from Magonia glabrata yielded shikimic acid, scopoletin, sitosterol glycoside and 2-O-methyl-l-inositol. Antioxidant, icthyotoxicity and brine shrimp lethality activities were observed in this extract. The major constituent, 2-O-methyl-l-inositol, was found to be inactive in two assays but showed moderate activity as a radical scavenger.     

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.     

Antiinflammatory and ulcerogenic activities of Salvia triloba extracts

In continuation of our research on Salvia triloba, acute and chronic antiinflammatory and ulcerogenic activities of chloroform, ethanol, butanol and water extracts were detected at 25 mg/kg p.o. The chloroform extract showed the highest antiinflammatory activity in both acute and chronic models, while the ulcerogenic effects of all tested extracts were found to be less than that of acetyl salicylic acid.     

Neuropharmacological properties of Xylocarpus moluccensis

The methanolic extracts of the barks and pneumatophores of Xylocarpus moluccensis were assessed for their effects on the central nervous system (CNS) using a series of established pharmacological tests including pentobarbitone-induced sleeping time, open field, hole cross, hole-board and evasions tests in mice model. These extracts produced a dose-dependent reduction of the onset and duration of pentobarbitone-induced hypnosis, reduction of locomotor and exploratory activities in the open field, hole cross, head-dip and evasion tests. These results suggest that both the bark and pneumatophore extracts possess CNS depressant activity, the pneumatophore extract being more potent than the bark extract.     

Inhibitory effects of selected Thai medicinal plants on Na+,K+-ATPase

Extracts of ten Thai indigenous medicinal plants having ethnomedical application in the treatment of dysuria were tested for their Na(+),K(+)-ATPase inhibitory activity. The hexane extracts of Cyperus rotundus and Orthosiphon aristatus showed high potent inhibitory activity on crude enzyme Na(+),K(+)-ATPase from rat brain.     

Comparison of bioactive compounds content, free radical scavenging and anti-acne inducing bacteria activities of extracts from the mangosteen fruit rind at two stages of maturity

Contents of bioactive components, free radical scavenging and anti-acne producing bacteria activities of young and mature fruit rind extracts of mangosteen were compared. The young fruit rind extract contained significantly higher contents of phenolics and tannins and promoted higher free radical scavenging activity than the mature fruit rind extract, while the later extract contained higher contents of flavonoids and α-mangostin xanthone and gave higher anti-acne producing bacteria activity than the young fruit rind extract. Thus, the young and mature stages of mangosteen fruit rind should be beneficial for further development of antioxidant and anti-acne pharmaceutical preparations, respectively.     

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.     

Larvicidal and growth inhibition of the malaria vector Anopheles stephensi by triterpenes from Dysoxylum malabaricum and Dysoxylum beddomei

Secondary metabolites from Dysoxylum malabaricum and Dysoxylum beddomei were tested against mature and immature stage of the mosquito vector Anopheles stephensi under laboratory conditions. The triterpenes 3beta,24,25-trihydroxycycloartane and beddomeilactone from D. malabaricum and D. beddomei showed strong larvicidal, pupicidal and adulticidal activity. They also affected the reproductive potential of adults by acting as oviposition deterrents. The highest concentration tested (10 ppm) of both compounds evoked more than 90% mortality and oviposition deterrence.     

Antitrypsin activity of extracts from Ecballium elaterium seeds.

The antitrypsin activity of extracts obtained from two different seed types of Ecballium elaterium, was tested in vitro. The presence of trypsin inhibitors in three chromatographed samples for each extract, showed a strong and specific antitrypsin activity.     

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.     

Apoptotic and free radical scavenging properties of the methanolic extract of Gentianella alborosea

Gentianella alborosea ("Hercampure") is a Peruvian species used in folk medicine for the treatment of a variety of health disorders. We tested the free radical scavenging (DPPH) and induction of apoptosis on a human uterus tumor cell line (HeLa) by its methanolic extract. The results showed a noticeable radical scavenging activity and a dose-dependent apoptotic effect.     

Nepetalactone content in shoot cultures of three endemic Nepeta species and the evaluation of their antimicrobial activity

Rapid micropropagation of Nepeta rtanjensis, N. sibirica and N. nervosa was performed. Qualitative and quantitative nepetalactone content in methanol extracts of in vitro grown plants was analysed by reverse-phase HPLC coupled with UV and MS detection. Only trans,cis-nepetalactone was detected in shoots of N. rtanjensis, while cis,trans-nepetalactone stereoisomer was present in N. sibirica. No nepetalactone was observed in shoots of N. nervosa. The antimicrobial activity of methanol extracts, against eight bacterial and eight fungal species, was evaluated. All the tested extracts showed significant antibacterial and strong antifungal activity. However, N. rtanjensis extract exhibited the best antimicrobial potential.     

Antibacterial and allelopathic activity of methanolic extract from Iris pseudopumila rhizomes

The methanolic extract of rhizomes of Iris pseudopumila was tested for its antibacterial and allelopathic activity. The extract was shown to have antibacterial effects. The allelopathic effect was tested against Raphanus sativus seed germination. The extract caused a decrease in the percentage of seed germination and root and epicotyl growth.