Compounds isolated from [Solanum nudum] have shown [in vitro] antimalarial activity against the FCB-2 strain of [Plasmodium falciparum] Diosgenone (C27H40O3) the main component isolated from the hexane extract and an aqueous extract were evaluated to measured their clastogenic potential using the micronucleus test. Three concentrations (16, 32 and 64 g/kg of weight) of the aqueous extract were administered intraperitoneally into mice, (the highest concentration corresponed to 80 percent LD50) and diosgenone solubilized in olive oil was inoculated at the highest concentration possible (11.187 g/kg of weight). After administration of the compounds, no induction of micronucleus was observed either in polychromatic or normochromatic erythrocytes. Interestingly, a reduction of 51 percent in the young/mature erythrocytes ratio was seen in cells treated with aqueous extract. It was concluded that neither diosgenone nor the aqueous extract have clastogenic activity, and that the aqueous extract showed some toxicity at the above mentioned concentrations.
Three fractions from leaves of [Aloe vera] and [Adhatoda vasica] were obtained on sephadex 25 column chromatography. Antifungal action of low molecular weight protein was tested against [Aspergillus niger, Trichoderma] spp., [Rhizopus] spp., and [Aspergillus flavus]. Results are reported and discussed.
Methanolic extracts of eight subspecies of genus [Argyranthemum] were evaluated against brine shrimps, human cancer cell lines, malarial parasites and microorganisms under in vitro conditions. In the shrimp assay samples of [A.adauctum spp. adauctum, A. adauctum spp. erythrocarpon] and [A.frutetescens spp. succulentum] were active with ED50 values in the range of around 300 to 360 micro g/ml. In the Caco-2, HepG2 and MCF-7 cell lines, the samples [A. adauctum spp. jacobaeifolium] and [A. adauctum ssp. palmensis] were active with LC50 values ranging between 80-90 micro g/ml. The secondary assay results of antimalarial activity of samples, [A.adauctum ssp.. adauctum], [A.adauctum spp. dugourii], [A..adauctum spp. erythrocarpon] and [A.adauctum spp. jacobaeifolium] have IC50 values less than 50 micro g/ml. The samples demonstrated broad specilic antimicrobial activity against five different microoraganisms.
Out of the six bacterial species tested [S.aureus] was the most susceptible. On the other hand, the extracts showed weak inhibitory effect against [S.epidermidis, B.subtilis, S.typhimurium] and [P.aeruginosa] while there was no inhibition zone observed for [E.coli] O157. The MIC values of the extracts ranged from 0.0781 mg/ml to 1.25 mg/ml whereas the MBC values ranged from 0.3125 mg/ml to 2.50 mg/ml. The MBC values of aqueous extract against [S.aureus] and [S.typhimurium] were higher than their MIC values. The MBC value of acetone extract against S.aureus was also higher than its MIC value. Interestingly, however, the MIC and MBC values of acetone extract against [S.typhimurium] were the same (1.25 mg/ml). The aqueous and acetone extracts displayed similarities in their antimicrobial activity on the bacterial species and as such, the gall of [Quercus infectoria] are potentially good source of antimicrobial agents.
Traditionally [Achyrocline satureioides], known as `marcela' has been used in South America for the treatment of several disorders. Three spray-dried extracts (N1, N2 and N3) were used, all of them prepared with 50 percent of an hydroethanolic extract rich in flavonoid compounds and 50 percent of blends of different adjuvants. The cytotoxic concentration which causes destruction in 50 percent monolayer cells (CC50) was 62.5 micro g/ml for the three extracts. The antiviral activity was evaluated by using two different strains of herpes simplex virus (HSV-1) and best results were obtained with KOS strain and N2 extract. Studies concerning the mechanism of the antiherpetic activity demonstrated that N2 extracts showed no virucidal effects or activity on cellular receptors. HSV-1 DNA synthesis was not inhibited. The antiherpetic activity occurred between the second and ninth hour of the virus replication cycle.
From the stem wood of [Erythrina latissima] two isoflavones and a flavanones were isolated and characterized in addition to 10 known flavonoids. Structures of these compounds were determined on the basis of their spectroscopic data. These compounds showed antimicrobial activity against [Escherichia coli], [Staphylococcus aureus], [Bacillus subtilis] and [Candida mycoderma]. The isolated compounds also exhibited weak radical scavenging properties towards DPPH radical.
The essential oils from the seeds of ajowan ([Trachyspermum ammi]) and celery ([Apium graveolens]) were screened for controlling the growth of bacteria and fungi. The oil of [T.ammi] has exhibited inhibitory action even more than streptomycin and salicylic acid against all bacteria and fungi whereas the oil of [A.graveolens] has shown average inhibitory action.
Extracts of [Abrus precatorius] and [Emblica officinalis] were prepared in petroleum ether, acetone, 90 percent methanol and water and tested against standard cultures of test bacteria. Significant antibacterial activity was exhibited by the petroleum ether, acetone and methanol extracts of [A.precatorius] and acetone, mthanol and aquous extracts of [E.officinalis]. The extracts of [A.precatorius] were found to be active at very low concentrations.
Methanol extracts of the seeds of [Piper guineense] known as Ashanti pepper or West African pepper (Piperaceae) were active against goldfish monogenean parasites. The seed extract of [P.guineense] was administered at different concentrations (0.5-2.0 mg/L) under [in vivo] and [in vitro] conditions. There was a higher efficacy of the effects of the extracts against fish parasites under [in vitro] situations than under [in vivo]. Three major compounds (piperanine, N-isobutyl (E,E)-2,4 decadienamide and delta alpha, beta-dihydrowasanine) were identified from the seed by LC-MS analysis.
Aerial parts yielded essential oil [Helichrysum forsskahlii], endemic to southern Saudi Arabia, was analyzed by GC/MS. Eighty-one compounds, representing more than 85.9 percent of the oil, were identified with selina-5,11-diene (45.3 percent), gamma-3-carene (7.8 percent), 1,8-cineole (4.2 percent) and beta-caryophyllene (4.9 percent) as main constituents. The major component, selina-5,11-diene, was isolated by column chromatography and its identity confirmed by 1 and 2D NMR spectral analysis. The oil showed only a very weak antimicrobial activity against [Mycobacterium smegmatis] with no activity against Gram-positive and Gram-negative bacteria or [Candida] test organisms. Likewise, seline-5,11-diene showed only a weak activity against [M.intracellulare].
Chemical study of [Cunonia macrophylla], a New caledonian Cunoniaceae, based on bioactive effects of a crude methanol extract of the leaves, detected bioactive tannins for the first time in this plant family. These ellagitannins have been identified as ellagic acid-4-O-beta-D-xylopyranoside (6), mallorepanin (3), mallotinic acid (1) along with corilagin (2), chebulagic acid (4), ellagic acid (5) and gallic acid (7) and have been shown to possess antimicrobial activity and to inhibit xanthine oxidase. Antimicrobial activity on bacterial human pathogens [Staphylococcus aureus, Corynebacteriumaccolans]) and on a plant pathogen [Erwinia carotovora] as well as on a human pathogenic yeast ([Candida albicans]) were investigated. Activity is reported here for the first time for compounds 1, 3, 4 and 6. The inhibitory effects of all molecules against xanthine oxidase in relation to their structure was evaluated and compared. Compound 6 present the best activity and seems to be a considerable interest for further studies.
Bioasay-guided fractionation resulted in the isolation of four antifungal agents from the roots of [Cudrania cochinchinensis]. Two of these were new compounds, cudraxanthone S(1) 1,3,5,6-tetrahydroxy-2-(1,1-dimethyl-2-propenyl)xanthone] and cudraflavanone B(2) 2',4',5,7-tetrahydroxy-6-prenylflavanone). the remaining two compounds were known compounds, toxyloxanthone C(3) and wighteone (4), Among these compounds, 1,3, and 4 exhibited antifungal activities against Cryptococcus neoformans, Aspergillus fumigatus, and A.nidulans (MICs = 2-8 micro g/mL). compounds 1 and 3 also showed antifungal activity against [Candida glabrata] (MICs = 4-8 micro g/mL.
Methanol, chloroform and aqueous extracts from [Senna villosa] (Leguminosae) were tested [in vitro) against epimastigote and trypomastigote forms of [Trypanosoma cruzi] responsible for causing Chagas disease. Methanol and chloroform extracts were found to possess significant activity against both forms of the parasite, while chloroform extract at doses of 1.65, 3.3, and 6.6 micro g/mL demonstrated trypanocidal activity similar to gentian violet and allopurinol.
Isolation of low molecular weight proteins through Hidex 25 column chromatography was carried out from leaves of [Ocimum sanctum] and [Curcuma longa]. Isolated protein fractions were tested against [Escheritia coli, Staphylococcus aureus] and [Bacillus subtilis].
Two new sesquiterpenoids (1 and 2) with a dihydro-beta-agarofuran skeleton were isolated from [Crossopetalum tenduzii]. Their structures were elucidated on the basis of spectral analysis, including homonuclear and heteronuclear correlation NMR experiments (COSY, ROESY, HSQC, and HMBC). Their absolute configurations were determined by CD studies on 3, the benzoylated derivative of 1. Chemical correlations have allowed the absolute configurations of 4 and 5, two previously known dihydro-bet-agarofuran analogues, to be reported for the first time. Compounds 1,2, and 5 showed strong antitumour-promoting activity on Epstein-Barr virus early antigen (EBV-EA) activation.
Extracts of leaves and bark of [Citrus sinensis], fruit rind of [Aegle marmelos] and bark of [Citrus aurantium] were found to be active against [Staphylococcus aureus, Escherchia coli, Pseudomonas aeruginosa] and [Proteus vulgaris] while bark of [Aegle marmelos] and leaves of [Murraya koengii] were found to be active against [Psudomonas aeruginosa] and leaves of [Citrus aurantium] were only active against [Proteus vulgaris].
A bioassay-guided fractionation of the ethyl acetate soluble fraction from the stem bark of [Styrax japonica] (Styracaceae) yielded two new lignan glycosides, styraxjaponoside A and styraxjaponoside B, along with three known compounds, matairesinoside, egonol glucoside, and dihydrodehydrodiconiferyl alcohol 9'-O-glucoside, The structures of all the compounds were determined by spectroscopic method, as well as 1D- and 2D-NMR (HSQC, 1H-1H COSY, and HMBC) spectroscopy. Among them, compound styraxjaponoside B exhibited potent inhibitory activity matrix metalloproteinase (MMP)-1, and prevented the UV-induced changes in the MMP-1 expression.
Activity-guided isolation of the acetone extract of the fruits of [Vitex trifolia] resulted in the isolation of two new norditerpene aldehydes, 1 and 2, together with five known diterpenes: vitexifolin E (3), vitexifolin F (4), vitexilactone (5), 6-acetoxy-9-hydroxy-13(14)-labden-16,15-olide (6), and previtexilactone (7). [In vitro] minimum lethal concentrations of the isolated compounds against epimastigotes of [Trypanosoma cruzi] were 11 microM (1), 36 microM (2), 34 microM (3), 34 microM (4), 66 microM (5), 66 microM (6), and more than 265 microM (7).
Activity guided isolation of the acetone extract of [Pogostemon cablin] resulted in isolation of three new sesquiterpene hydroperoxides 1-3, together with a known sesquiterpene, patchouli alcohol (4). [In vitro] minimum lethal concentrations of the hydroperoxides 1-3 against epi-mastigotes of [Trypanosoma cruzi] were 0.84 microM (1), 1.7 microM (2) and 1.7 microM (3). The activity of the corresponding alcohols and patchouli alcohol was very weak (MLC more than 200 microM.
[Piper crassinerving], [P. aduncum], [P.hostmannianum], and [P. gaudichaudianum] contain the new benzoic acid derivatives crassinervic acid, aduncumene, hostmaniane, and gaudichaudianic acid, respectively, as major secondary metabolites. Additionally, 19 known compounds such as benzoic acids, chromenes, and flavonoids were isolated and identified. The antifungal activity of these compounds was evaluated by bioautographic TLC assay against [Cladosporium] species.
The aqueous extracts from 21 medicinal herbs were screened for activiral activities against human herpes simplex virus type 1 (HSV-1) and human respiratory syncytial virus (RSV) using a cytopathic effect (CPE) reduction assay. Three extracts from [Agrimonia pilosa], [Pithecellobium clyperiar] and [Punica granatum], respectively, showed antiHSV1 activity, which was possibly contributed by the polyphenolic compounds in the herbal extracts. Six of the extracts, from [Blumea laciniata], [Elephantiopus scaber] [Laggera pterodonta] [Mussaenda pubescens], [Schefflera octophytta] and [Scutellaria indica], respectively, exhibited anti-RSV activity with 50 percent inhibition (IC50) concentrations ranging from 12.5 to 32 micro g/mL, and selective indices (SI) ranging from 11.2 to 40. In addition to polyphenolic compounds, other constituents presents in these extracts may also contribute to their antiRSV activity.
Antifungal activity bioassay-guided isolation of the ethanol extract of the roots of [Pentagonia gigantifolia] yielded 6-octadecynoic acid (1) and the new 6-nondecynoic acid (2). compounds 1 and 2 inhibited the growth of fluconazole-susceptible and -resistant [Candida albicans] strains. Their antifungal activity potencies were comparable to those of amphotericin B and fluconazole. Of particular significance is the low cytotoxicity and specific activity of 1 and 2 against [Candida albicans].
Methanol extract, ethyl acetate, dichloromethane, n-hexane, n-butanol and chloroform fractions of [Senecio inaequidents] and [Senecio vulgaris] were assayed. The hexane extract of [Senecio vulgaris] (MIC 0.031 mg/ml) showed significant activity against [Trichophyton tonsurans] antibacterial.
Petroleum ether, acetone, 90 degreelo methanol and water extracts of the thalamus of [Sphaeranthus indicus] were tested against the bacterial cultures by well diffusion method. Considerable antibacterial activity against some test bacterial cultures was detected in all the extracts. All the extracts exhibited strong antifungal activity against all the best fungal cultures.
The ethanol extracts of fresh apical stems of [Phyllanthus niruri] (Euphorbiaceae) cultured on MS medium supplemented with IBA/BAP/ [Cocos nucifera] (Palmae) milk for 1,2,4, and 6 months were investigated and compared to the intact plant part and whole plant extracts. A phytochemical screening revealed the presence of steroids, terpenes, and flavonoids as the major constituents but same constituents were not detected in all extracts. Alkaloids were detected in whole plant extract and were in traces in the intact apical stem extract and callus extracts. Results from the [in vitro] antiplasmodial testing indicated that the callus extract 1 month old (IC50 = 16.3 plus or minus 2.5 micro g/ml) exhibited activity similar to the intact plant part extract (IC50 = 18.2 plus or minus 2.5 micro g/ml). This activity was significantly higher than that exhibited by extracts from callus cultures 2,4, and 6 months old (25 less than IC50 less than 40 micro g/ml). The activity of these extracts is lower than that displayed by the same extract from the whole plant (IC50 = 2.5 plus or minus 0.2 micro g/ml).
Sixteen more Amaryllidaceae alkaloides have been isolated from bulbs of [Crinum kirkii] of which noraugustamine and 4a, N-dedihydronoraugustamine are hitherto unknown. Their structures and those of earlier known alkaloids have been established by physical and spectroscopic analysis. Application of 2D NMR techniques was used for complete characterization of the alkaloids as well as of 3-O-acetylsanguinine 1,2-Diacetyllycorine and 3-O-acetylsanguinine showed activity against Trypanosoma brucci rhodesiense, the parasite associated with sleeping sickness, 3-O-acetylsanguinine also-showed some activity against Trypanosome cruzi.
Bioassay-guided chromatographic separation of the antimycobacterial activity extract of the leaves of [Piper sanctum] afforded 14 new compounds, identified as 2-oxo-12-(3',4'-methylenedioxyphenyl)dodecane, 2-oxo-14-(3',4'-methylenedioxyphenyl)tetradecane, 2-oxo-16-*3',4-methylenedioxyphenyl)hexadecane, 2-oxo 18-(3'4'-methylenedixyphenyl)octadecane, 2-oxo-14(3',4'-methylenedioxyphenyl)-trans-13-tetradecene, 2-oxo-16-(3',4'-methylenedioxyphenyl)-trans-15-hexadecene, 2-oxo-18-(3',4'-methylenedioxyphenyl)-trans-17-octadecene, 2-oxo-16-phenyl-trans-3-hexadecene, methyl [6-(10-phenyldecanyl)tetrahydropyran-2-yl]acetate, methyl 2-(6-tridecyltetrahydro-2H-pyran-2-yl)acetate, methyl 2-(5-tetradecyltetrahydro-2-furanyl)acetate, 2-oxo-14-(3',4'-methylenedioxyphenyl)-trans-3- tetradecene, 2-oxo-16-(3',4'-methylenedioxyphenyl)-trans-3-hexadecene, and 2-oxo-16-phenyl-3- hexadecane. In addition, p-eugenol, methyleugenol, Z-piperolide, demethoxyyanonin, 5,6-dehydro-7,8-dihydromethysticin, cepharanone B, piperolactam A, cepharadione B, N-trans-feruloyltyramine, and N-trans-(p-coumaroyl) tyramine were obtained from the anti-TBC stem extract of plant. GC-MS and HPLC analyses of the essential oils of the leaves and stem revealed that safrol was the major component of the oils. Some of the Compounds inhibited the growth of Mycobacterium tuberculosis when tested by the MABA assay, with MIC values ranging from 4 to 64 micro g/mL..
The methanol extract (50 percent W/V), prepared from the bark of [Sonneratia apetela] was found to be highly potent with MIC of 100 mg/ml against gram positive and gram negative bacteria. Activity guided fractionation indicated activity in all three fractions (petroleum ether, water and methanol). The most significant zones of inhibition were found in water and methanol fraction of bark extract. Analysis of this fraction afforded the isolation of coumarin, glycoside, tannin, anthraquinone, flavonoids and alkaloid. Bioautography of active methanol fraction with chloroform: acetone resulted one band which was found to be bioactive. The confirmatory test of this band indicated the active compound was coumarin.
The antibacterial efficacy of the methanol extract of flowers of [Mesua ferrea] was studied against various strains of bacteria. It could inhibit a large number of Gram-positive and Gram-negative bacteria at concentration ranges of 100 to 50 micro g/ml, or even lower, as against vibrios and [Escherichia coli]. In [in vivo] tests, used at concentrations of 100 to 200 micro g/g of body weight, it offered significant protection to Swiss strain of albino mice when challenged with 50 MLD of a virulent strain [Sulmonella typhimurium] ATCC 6539. Mortality in mice due to these two dosages of the extract alone was insignificant. The extract at 200 micro g/g body weight dosage, could significantly reduce the viable count of the strain [Salmonella typhimurium] ATCC 6539 in liver, spleen and heart blood of the extract treated challenged mice.
A new efficient synthetic approach to the natural coumarins 5-hydroxyseselin (5), 5-methoxyseselin (3), and (plus or minus) cis-grandmarin (9) is described as well as the synthesis of some new derivatives in the 5-methoxyseselin series (10-15). The natural coumarins 7-hydroxyalloxanthyletin (6), alloxanthoxyletin (8), and dipetalolactone (7) have also been obtained as secondary products. The type of fusion of the pyrano ring in all cases has been established by 2D NMR spectroscopy. The compounds have been studied for their [in vitro] antibacterial activity, which has been compared with that of some previously synthesized seselin derivatives. The most active compounds were 3,7,8,11 and 14. Some structure-activity relationships are discussed.
The antimicrobial activity of ethanolic extract and pure compounds of [Gomphrena celosioides] (Amaranthaceae) has been screened by Kirby-Bauer method. Quantitative determination of 4-hydroxy-3-methoxy-benzoic acid in stems, leaves, flowers and roots was established by TLC-densitometry. Results showed significant activity against [Staphylococcus aureus] and [Salmonella typhi]. There were no significant differences in the determined benzoic aicd derivative.
Work demonstrates the fungistatic and bacteriostatic (Antibacterial activity) activities of affinin, the main alkamide of [Heliopsis longipes] (Asteraceae) roots and two alkamides obtained by catalytic reduction of affinin: N-isobutyl-2E-decenamide and N-isobutyl-decanamide. The bioactivity was tested against [Rhizoctonia solani] groups AG3 and AG5 [Sclerotium rolfsil][Sclerotium cepivorum][Fusarjum sp.] [Vertcillium sp] [phytopathogenic] fungi [Phytophthora infestans] a phytopathogenic Chromista. [Saccharomyces cerevisiae] a nonphytopathogenic ascomycete; and [Escherichia coli] [Erwinia earotovora] and [Bacillus subtilis] bacteria. Affinin, being the primary component of the lipidic fraction, is expected to be responsible for the fungitoxic activity observed in roots of this plant species. Four of the assayed fungi showed an important sensitivity to the presence of affinin [S.rolfsii, S. cepivorum, P. infestans] and [R.solani] AG-3 and AG-5, displaying a growth inhibition of 100 percent. [S. cerevisiae] showed a similar growth inhibition with affinin. None of the alkamides obtained by catalytic reduction of affining showed a fungitoxic activity. In both cases, this alkamide was more potent than affinin. On the other hand, only N-isobutyl-decanamide displayed a significant activity on the growth of [B.subtilis].
The Nigerian traditional soft soaps prepared using varied locally sourced raw materials such as cocoa pod ash ([Theobroma cacao]) palm kernel shaft ash ([Elaies guineensis]) have been evaluated for their physico-chemical properties and anti-microbial activities using standard pharmacopoeia protocols and an [in-vitro] agar diffusion bioassay method. The antimicrobial activity was evaluated with and with and without the incorpocation of [Aloe vera] and [Ageratum conysoides] extractives into the soap samples. The incorporated medicinal plants used in this study, however, did not show any significant effect on the anti-microbial activities exhibited by the various soaps against the bacterial and fungal test organisms.
Sixty-five different extracts from 22 plants belonging to 6 of the most representative families were investigated through the plate-well diffusion assay against the following bacteria: [Bacillus subtilis, Escherichia coli, Klebsiella pneumoniae, Pseudomonas aeruginosa] and [Staphylococcus aureus]. The plant extracts were obtained by Soxhlet in n-hexanes, dichloromethane, and methanol. Of these, 32.31 percent of the extracts were active against [B.subtilis], 10.77 percent exhibited activity against [K. pneumoniae] 7.69 percent of the plant extracts showed activity against [P. aeruginosa], 9.23 percent were bioactive to [S.aureus] and 4.61 percent were found to be active against [E.coli]. The methanol extracts from the plants studied exhibited the highest antibacterial activity.
The synergistic activity of antimycobacterial constituents from Saudi plants was evaluated in combination with isonicotinic acid hydrazide (INH) against four atypical organisms, namely, [Mycobacterium intracellulare, M.smegmatis, M.xenopei] and [M.chelonei]. The potency of INH was increased four-fold, using an [in vitro] checkerboard method, against each mycobacteria when tested with a subtoxic concentration of the totarol, isolated from [J.procera]. The MIC values of totarol, ferulenol (from [Ferula communis] and plumbagin (from [Plumbago zeylanica] were thus lowered from 1.25-2.5 to 0.15-0.3 microg/mL due to synergism with INH. When tested against the resistant strain of [M.tuberculosis] 1137Rv, plumbagin and 7beta-hydroxyabieta-8, 13-dien-11,12-dione exhibited inhibitory activity at 12.5 microg/mL, while others were inactive at this concentration.
[Pennisetum purpureum] contains 1.5 percent Pennisetum essential oil and 3.5 percent fixed oil. The oil is rich in phospholipids and sterols. Vitamin contents were also found in large quantities. The plant contains tannin, phytate but no haemagglutinin. Phytochemical studies that the plant contains a broad spectrum of secondary indicate metabolies like alkaloids, saponins, flavonoids, glycosides and cyanogenic glycosides. The elemental composition of the plant revealed the presence of calcium, iron, magnesium, potassium and sodium. Antimicrobial studies showed remarkable inhibition of test organisms, [Cacillus, subtilis, Escherichia coli, Pseudomonas aeruginosa, Staphylococcus aureus] and [Aspergillus niger].
Whole root preparations of three Nigerian medicinal plants, [Anthocleista dijalonensis, Nauclea latifolia] and [Uvaria afzalii], were extracted by maceration in ethanol, cold and hot water, respectively. The extracts were tested, by agar diffusion and macrobroth dilution methods, for activity against five strains of [Staphylococcus aureus] and two to [Escherichia coli] isolated from cases of STD and or urethritis. Ethanolic and cold-water extract of [Anthocliesta djalonensis] exhibited activity against 9 and 7, respectively, of the 11 test organisms. They were bacteriostatic at minimum inhibitory concentrations (MIC) to the Gram positive strains but bactericidal to the Gram negative strains. Similar crude extracts of [Uvaria afzalii] showed bactericidal activity restricted to Gram positive ([Staphylococcus aureus] and [Bacillus subtilis]) strains. [Nauclea latifolia] extracts were bacteriostatic to both Gram positive and Gram negative strains. No test strain was susceptible to the hot water extracts of [Nauclea latifolia] but five and seven strains, were susceptible to similar extracts of [Anthocliesta djalonensis] and [Uvaria afzalii]. Thus, partial purification seems to broaden the spectrum of antibacterial activity and generally improve the potency of [Uvaria afzalii].
Ethanol extracts of five plants [Astrodaucus orientalis], [Bifora radians], [Conium maculatum], [Crithmum maritimum], [Daucus carota] containing furanocoumarins and standard furanocoumarins (umbelliferone, xanthotoxin, and bergapten) were tested against [Escherichia coli, Pseudomonas aeruginosa, Bacillus subtilis, Staphylococcus aures] and [Candida albicans] using a microdilution method. The minimum inhibition dilution values of the extracts were determined. [Astrodaucus orientalis] showed the highest antibacterial activity.
Bioassay (P388 lymphocytic leukemia cell line and human cancer cell lines) (Anti cancer activity) guided separation of an extract prepared from the stem bark and twigs of the previously uninvestigated [Ruprechtia tangarana] led to the isolation of a new isocarbostyril designated ruprechstyril, secalonic acid A, 2'-O-methylevernic acid, 3,3' 4-tri-O-methylflavellagic acid, lichexanthone, methyl asterrate, and 3beta, 22E, 24S-stigmasta-5,22-dien-3-ol. Only secalonic acid A exhibited cancer cell and microbial growth inhibition. The structure of ruprechstyril (1) was determined by HRMS and 1D NMR spectra and confirmed by single-crystal X-ray analysis. The structures and absolute stereochemistry of five of the other compounds were also established by X-ray crystal structure determination.
The antifungal activity of [Glycosmis calcicola] (Rutaceae) and [G.rupestris] extracts was evaluated using poison food and spore germination techniques. The CHCl3 extract of [G.calcicola] has been shown to be most effective in inhibiting mycelial growth, sporulation, and spore germination on three fungal pathogens of chili. The antifungal compounds were identified as flindersine and desmethoxyanthophylline and their structures were determined by spectroscopic methods and comparision with reported data.
The chemical composition of the essential oil obtained by hydrodistillation of [Pistacia vera] (Pistaciaceae) gum was analyzed using GC-MS. Twenty compounds were identified, representing 99.5 percent of the total components. Pinenes alpha and beta), and alpha-thujene were found to be the major constituents. The bacteriostatic activity of the essential oil against 12 clinical isolates of [Helicobacter pylori] was determined using the hole-plate method. All isolates were sensitive to the essential oil, and the MIC was 1.55 mg/ml for all isolates using the agar dilution method.
An extract of leaves and stems of [Peperomia villipetiola] has been found to contain myristicin (3-methoxy-4, 5-methylenedioxy allylbenzene) and seven chromenes. The anti-fungal activities of the chromenes were measured bioautographically against [Cladosporium cladosporioides] and [Cladosporium sphaerospermum] compounds and 7 were found to be the most active.
Bioactivity-guided fractionation of the methanolic extract of [Psorothamnus polydenius] yielded the new chalcones 2,2',4'-trihydroxy-3',5'-dimethylchalcone (2), together with six other known compounds, 2',4'-dihydroxy-6'-methoxy-3',5'-dimethylchalcone (1), dalrubone (3), demethoxymatteucinol (4), eriodictyol (5), and photodalrubone (6a and 6b). This is the first report of chalcones in [P.polydenius]. The extracts and isolated compounds were tested [in vitro] for their antiprotozoal activity against [Leishmania donovani] and [Trypanosoma brucei]. Chalcones 1 and 2 and dalrubone (3) exhibited leishmanicidal (IC50 5.0, 7.5, and 7.5 microg/mL, respectively) and trypanocidal activity (IC50 6.3, 6.8 and 21.6 microg/mL, respectively) properties. Dalrubonz (3) displayed 6-fold selectivity for axenic [L.donovani] parasites over Vero cells. Furthermore, treatment of [L.mexicana]-preinfected mcrophages with chalcones 1 and 2 and dalrubone (3) (12.5, 12.5 and 25 microg/mL, respectively) reduced the number of infected macrophages by at least 96 percent while posing no toxicity to the host cell.
The antibacterial activity of the six compounds against vancomycin-resistant enterococci (VRE) was estimated by determining the minimum inhibitory concentration (MIC). Of the six isoflavanoids, erybraedin A ((6aR, 11aR)-3,9-dihydroxy-4,10-di(gamma,gamma-dimethylallyl)pterocarpan) exhibited the highest growth inhibitory potency against VRE with an MIC value of 1.56-3.13 microg/mL, followed by eryzerin C ((3R)-7,2',4'-trihydroxy-6,8-di(gamma,gamma-dimethylallyl)isoflavan) (MIC 6.15 microg/mL). These compounds also inhibited the growth of methicillin-resistant [Staphylococcus aureus] (MRSA) at 3.313-6.25 microg/mL. The antibacterial effects of the two compounds against VRE and MRSA were based on bacteriostatic action. When erybraedin A or eryzerin C was combined with vancomycin, the fractional inhibitory concentration (FIC) index against VRE ranged from 0.5306 to 1.0 and from 0.5153 to 0.75, respectively. The combinations also showed FIC indices of 0.6125-1.0 against MRSA. The results indicate that, depending on the case, both compounds act either synergistically or additively with vancomyin against VRE and MRSA. Erybraedin A and eryzerin C show evidence of being potent phytotherapeutic agents against infections caused by VRE and MRSA.
The new steroidal saponin, 26-O-beta-D-glucopyrnosyl-3beta,26-dihydroxy-20,22-seco-25(R)-furost-5 -en-20,22-dione-3-O-alpha-L-rhamnopyranosyl-(1 to 4)-alpha-L-rhamnopyranosyl-(1 to 4)-[alpha-L-rhamnopyranosyl-(1 to 2)[-beta-D-glucopyranoside, along with two known methyl protodioscin, asperoside and prosapogenin A of dioscin were isolated from the rhizomes of [Dioscorea cayenensis] (Dioscoreaceae). Their structures were established mainly on the basis of 600 MHz 2D-NMR spectral data. Prosapogenin A exhibited antifungal activity against the human pathogenic yeasts [Candida albicans, C. glabrata] and [C.tropicalis] (MICs of 20.8, 6.25, 25 micro g/ml, respectively), whereas saponins were inactive.
The diluted essential oil of [Mentha longifolia] var. [chlorodictya] foliage enhanced the bactericidal activity of nitrofurantoin decreasing the minimum inhibitory concentration (MIC) of nitrofurantoin for nitrofurantoin-resistant strains of Enterobacteriaceae. Thin-layer chromatography (TLC) analysis of the essential oil detected a fraction (Rf=0.35, UV 2max of 232.5), which was the most effective in enhancement of nitrofurantoin activity. Using gas liquid chromatography and known standards, the active fraction was identified as piperitone. 1 microl of the piperitone fraction decreased the MIC of nitrofurantoin 3-20 fold for the different strains of Enterobacteriaceae tested.
Activity of Liliaceae plants, [Allium sativum] and [Aloe barbadensis] and [Solanum nigrum] (Solanaceae) was tested against some common fungal species associated with superficial mycoses. The ethanol and aqueous extracts of these plants were tested to establish the antimycological effects against dermatophytes, saprophytes, and [Candida] species isolated from infected hospitalized patients. The [in vitro] antifungal activity was established by observing and measuring the zones of inhibition formed on selective nutrient media. Zones of inhibition were categorized as very high (41-50 mm), high (31-40 mm), medium (21-30 mm), and low (11-20 mm). High zones of inhibition were noted with ethanol extracts of plants evaluated.
Essential oil of [Agastache rugosu] containing estragole significantly inhibited growth of fungal species. The anti-[Candida] effects of estragole combined with amphotericin B or ketoconazole, were evaluated. The fractional inhibitory concentration (FIC) indices of both estragole combined with ketoconazole against [c.albicans] and [C.utilis] calculated from the checkerboard microtiter assay were 0.28 and 0.50, respectively, indicating significant synergism. These drug combination exhibited additive effects against [C. tropicalis] with FIC index of 0.75. Consistent for the most part with the results from the checkerboard titer tests, the time-kill curves of the tested samples also indicated significant synergism or additive effect between ketoconazole and estragole against the [Candida] species evaluated. In contrast, amphotericin B showed antagonism in combination with estragole in most experiments. The synergistic combination effects shown by estragole and ketoconazole may be effective combinations for the treatment of [Candida] infection.
The most abundant essential oil components of leaf oil of [Heteropyxis dehniae] obtained by hydrodistillation are linalool (58.3 percent), 4-terpineol (9.8 per cent), alpha-terpineol (3.6 percent), and caryophyllene oxide (3.1 percent). The antimicrobial activity and the [in vitro] cytotoxicity of the oil of PC-3, MDA-MB-231, Hs 578T, MCF7, SK-MEL-28, and 5637 human tumour cells were examined. Caryophyllene oxide shows notable cytotoxic activity with LC50 values of 147-351 micro M.
The antifungal activity of [Aniba rosaeodora] [Laurus nobilis] [Sassafras albidum] and [Cinnamomum zeylanicum] essential oils were investigated against 17 micromycetes. Among the tested fungal species were food poisoning, spoilage fungi, plant and animal pathogens. In order to determine fungistatic and fungicidal concentrations (MIC and MFC) macrodilution and microdilution tests were used. Linalool was the main component in the essential oil of [Aniba rosaeodora], while 1.8-cineole was dominant in [Laurus nobilis]. In [sassafras] essential oil safrole was the major component and in the oil of [Cinnamomum zeylanicum] the main component was trans-cinnamaldehyde. The essential oil cinnamon showed the strongest antifungal activity.
Both root and stem extracts were tested separately using different solvents for the extraction of active soluble principles. The highest ZOI in the extract of root was found to be 25 mm under 200 mg/ml concentration of acetone followed by 23 mm under 100 mg/ml concentration of the same solvent. All the concentrations of the root with ethyl acetate extract were found to be least effective. The antimicrobial efficacy of the chloroform extract was next to that of acetone extract. The acetone extract of stem (200 mg/ml) was found to be highly effective against [Staphylococcus aureus], which gave ZOI of 24 mm. followed by 20 mm under 100 mg/ml concentration of the same solvent and that of 100 mg/ml of benzene extract. The most ineffective extract was that of petroleum ether in which only a very small zone (8 mm) of bacterial inhibition was recorded for 50 mg/ml whereas both 100 and 200 mg/ml concentrations proved ineffective. In rest of the solvents both root and stem extracts exhibited varying degree of inhibitory activity.
Hexane extract of strobile hops [Humulus lupulus] was undertaken to isolate the characterize the antimycobacterial activity constituents using the fast-growing mycobacterial species [Mycobacterium fortuitum]. GC-MS of the derivatives indicated the presence of palmitic, stearic and oleic acids with small quantities of fignoceric, arachidic, behenic and linoleic acids. These compounds were assessed against [M.fortuitum] and all saturated fatty acids were inactive at concentrations greater than 256 micro g/ml, whereas the unsaturated fats oleic and linoleic acids displayed minimum inhibitory concentrations of between 4 and 16 micro g/ml against the fast-growing species tested. It has been stated that GC-MS of derivatised components of lipophilic extracts be a first step before any antimycobacterial activity bioassay-guided study, as this technique is the method of choice for dereplication of fatty acids.
The polyphenols examined were epigallocatechin (1), epigallocatechin-3-O-gallate (2), punicalagin (3), tannic acid (4), castalagin (5), prodelphinidin (6), geraniin (7), procyanidins (8). a theaflavin mixture of black tea (9), and green tea polyphenols treated with loquat polyphenol oxidase (10). The average MICs of all polyphenols against [Staphylococcus aureus] and the genus [Vibrio] (192 plus or minus 165 microg/ml, respectively) were much lower than the values against the genus [Salmonella] and [E.coli] (795 plus or minus 590 and 1519 plus or minus 949, microg/ml, respectively) (p more than 0.01). The coefficient of variation of the MICs of all polyphenols against [S.aureus] was least and that against the genus [Vibrio] was the greatest. The mean MICs of each plant polyphenols against [S.aureus] (98-389 microg/ml and the genus [Vibrio] 68-488 microg/ml) were similar. The relatively lower mean MIC values of 1, 2, 5, and 6 suggest the importance of 3,4,5-trihydroxyphenyl groups in antibacterial activity.
The ethanolic root extract of [Scrophularia lepidota], an endemic plant of the Turkish flora, has been investigated for its anti-protozoal and inhibitory effect towards plasmodial enoyl-ACP reductase (FabI), a key enzyme of fatty acid biosynthesis in [Plasmodium falciparum]. Chromatographic separation of the extract yielded 10 iridoids (1-10), two of which are new, and a known phenylethanoid glycoside (11). The structures of the new compounds were determined as 3,4-dihydro-methylcatalpol (8) and 6-O-4-[4"-O-trans-(3,4-dimethoxycinnamoyl)-alpha-rhamnopyranosyl]aucub in (scrolepidoside, 9) by spectroscopic means. The remaining metabolites were characterized as catalpol (1), 6-O-methylcatalpol (2), aucubin (3), 6-O-alpha-L-rhamnopyranosyl-aucubin (sinuatol, 4), 6-O-beta-D-xylopyranosylaucubin (5), ajugol (6), ajugoside (7), an iridoid-related aglycone (10) and angoroside C (11). Nine isolates were active against [Leishmania donorami] with the new compound 9 being most potent (IC50 6.1 micro/ml). Except for 4, all pure compounds revealed some trypanocidal potential against [Trypanosoma brucet rhodesiense] (IC50 values 29.3-73.0 micro g/ml). Only compound 10 showed moderate anti-plasmodial (IC50 40.6 micro g/ml) and FabI enzyme inhibitory activity (IC50 100 micro/ml). 10 is the second natural product inhibiting the fatty acid biosynthesis of [Plasmodium falciparum].
Garlic ([Allium sativum]), cinnamon ([Syzygium aromaticum]) and cloves have antimicrobial activity against common pathogens like [Escherichia coli] and [Bacteroides fragilis]. All three of these herbal extracts inhibited the growth of [E. coli] by 3 to 4 logs for a period of 24 hours or more. [Bacteroides fragilis], a strict anaerobic pathogen was inhibited by 3 to 4 logs at 24 hour period. However, these extracts had very little or no effect on the adherence properties of these microorganisms. The medical importance of these herbs in the prevention of [E.coli] diarrhoea and [B.fragilis] and other anaerobic dental infections is obvious considering the growing number of these organisms developing resistance to conventional antibiotics.
Phytochemical studies of an ethanolic extract of [Euclea natalensis] root bark afforded two new compounds, octahydroeuclein and 20(29)-lupene-3beta-isoferulate, in addition to three known compounds, shinanolone, lupeol, and betulin. The chemical structures were determined by spectroscopic means. Shinanolone showed antibacterial activity against Gram-positive bacterial strains and a drug sensitive strain of [Mycobacterium tuberculosis] at a concentration of 0.1 mg/mL.
Ethanol extract of leaves of [Piper porphyrophyllum] showed a broad spectrum of antibacterial activity. The activity was increased on fractionation (hexane, dichloromethane and aqueous), particularly in the aqueous fraction. No activity was shown against tested [Candida albicans].
The volatile components of two essential oils obtained from plants indigenous to Nepal, anthopogon ([Rhododendron anthopogon]) and [Curcuma zedoaria] oils, and four oils, chamomile ([Chamomilla recutita]), French basil ([Ocimum basilicum]), cornmint ([Mentha canadensis]) and palmarosa ([Cymbopogon martini] var. [martini]) which are exotic but produced in Nepal, were analyzed with GC/MS and the antimicrobial activity of all the six oils were examined using Petriplate-paper disk method. The microorganisms tested were [Staphylococcus aureus] IFO (14462), [Corynbacterium amycolatum] (IFO 15207), [Escherichia coli] (IFO 15034), [Candida albicans] (IFO 1594) and [Aspergillus ochraceus] (IFO31221). Anthopogon oil contained gamma-cadinene (11.4 percent) and [Curcuma zedoaria] oil contained 1,8-cineole (15.8 percent) and beta-eudesmol (10.6 percent) as the major volatile components. All of the examined oils indicated antimicrobial activity .
Utilizing high-throughput isolation, purification, and analysis methods applied to a natural products library, a new mass-limited antibacterial indolosesquiterpene, suaveolindole (1), was obtained from [Greenwayodendron suaveolens]. The miniaturization of the structure elucidation of 1 was performed primarily using the CapNMR probe. Compound 1 was found to possess significant [in vitro] antibacterial activity against the Gram-positive bacteria [Bacillus subtilis] (ATCC 43223), [Staphylococcus aureus] (ATCC 6538P), and methicillin-resistant [Staphylococcus aureus] (ATCC 33591), with MIC values of 4, 8, and 8 microg/mL, respectively.