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PubMed1991

The inhibitory effect of plant extracts on the collagenolytic activity and cytotoxicity of human gingival fibroblasts by Porphyromonas gingivalis crude enzyme.

It is well known that plant extracts inhibit some enzymatic activities. The present study examined the inhibitory effects of natural plant extracts against the collagenolytic activity of Porphyromonas gingivalis. The enzyme was isolated from a culture supernatant of P. gingivalis 381. The aqueous and 50% ethanolic extracts of Ginkgo biloba, Mosla chinensis, Salvia officinalis, Cinnamomum cassia, and a catechin extract of Camellia sinensis exhibited strong inhibitory effects on collagenolytic activity. The activities of these plant extracts were higher than that of tetracycline-HCl. They also inhibited the cytotoxicity of P. gingivalis crude enzyme against human gingival fibroblasts. C. sinensis catechin was the most effective agent in neutralizing the cytotoxicity of P. gingivalis. The aqueous and 50% ethanolic extracts of C. cassia had relatively strong anti-cytotoxic activity. Although the other samples strongly inhibited the collagenolytic activity of P. gingivalis, they were not effectively anti-cytotoxic. The present findings suggest that C. sinensis and C. cassia extracts are effective in reducing the pathogenicity of periodontopathic bacteria.

Catechin↗
PubMedDate not supplied

The metabolic activation of 4-nitro-o-phenylenediamine by chlorophyll-containing plant extracts: the relationship between mutagenicity and antimutagenicity.

Chlorophyllin, the sodium and copper salt of chlorophyll, chlorophyll a, and chlorophyll b were tested for their ability to inhibit the mutagenic activity of the direct-acting mutagen 4-nitro-o-phenylenediamine (NOP) and its plant-activated mutagenic enhancement. All three forms of chlorophyll were antimutagenic against both NOP and its plant-activated product, with chlorophyllin proving most effective. Chlorophyll-containing plant extracts, however, proved very efficient at activating NOP into a mutagen of greater potency. When these extracts were assayed for total chlorophyll content it was found that they contained far less chlorophyll than was required for an antimutagenic effect to occur. Thus, the balance between chemical mutagen activation and/or enhancement by chlorophyll-containing plant extracts and the potential antimutagenicity of these plant extracts is a function of chlorophyll concentration. The data presented here indicate that this balance must be taken into consideration in future studies investigating the efficacy of complex natural plant extracts as antimutagenic substances.

Biotransformation↗
PubMed2004

Adulticidal activity of some Malaysian plant extracts against Aedes aegypti Linnaeus.

The adulticidal activity of methanol extracts from three Malaysian plants namely Acorus calamus Linn., Litsea elliptica Blume and Piper aduncum Linn. against adult of Aedes aegypti (L.) were studied. Standard WHO bioassay tests were used to evaluate the effectiveness of these plant extracts. The hexane fraction from methanol extract of Acorus calamus rhizome was the most effective, exhibiting LC50 and LC90 values of 0.04 mgcm(-2) and 0.09 mgcm(-2) respectively. For L. elliptica, the methanol fraction also displayed good adulticidal property with the LC50 and LC90 values of 0.11 mgcm(-2) and 6.08 mgcm(-2) respectively. It is found that hexane fraction of the P. aduncum crude extract was the least effective among the three plants showing LC50 and LC90 values of 0.20 mgcm(-2) and 5.32 mgcm(-2), respectively. However, although A. calamus showed lowest LC values, the LT50 results indicated that the methanol fraction of L. elliptica was most potent extract among the extracts tested.

Journal Article↗
PubMed2004

Mechanisms underlying antigonadotropic effects of some traditional plant extracts in pituitary cell culture.

Previous works have demonstrated that stem bark extracts of Cola nitida (Sterculiaceae), Afrormosia laxiflora and Pterocarpus erinaceus (Fabaceae) provoked a blockade of female rat ovulation and estrous cycle by inhibiting pituitary LH release in vivo. In addition, these plant extracts exerted an inhibitory effect on LH release of rat pituitary cells. Therefore, these data could explain inhibitory effects of plant extracts on LH release in vivo. The present study was undertaken to examine the mechanisms by which these plants exert their antigonadotropic activities. So, we studied the biological activities of these plant extracts on pituitary cells in culture. Data show that C. nitida, A. laxiflora and P. erinaceus extracts only inhibit LH release and have no effect on FSH release. In fact, A. laxiflora, P. erinaceus and C. nitida extracts diminish LH release in culture medium without acting on rat pituitary cell content. Plant extracts form complexes with basic glycoproteins (but not with acid glycoproteins) and prevent them from entering the cells.

Animals↗
PubMed2005

Antibacterial effect of plant extracts against Helicobacter pylori.

The aim of this work was to evaluate the antibacterial effect of plant extracts as alternative and[sol ]or as active agents supporting antibiotics for treating Helicobacter pylori infection. The effect of either, ethanolic or aqueous extracts from 17 plant materials were studied against one H. pylori standard strain and 11 clinical isolates using a disc diffusion test and by evaluating the minimum inhibitory concentration (MIC) on solid media. An inhibitory activity against H. pylori strains was recorded in a large percentage of tested plants. MIC values of ethanolic extracts were from two to four concentration steps lower than the aqueous ones. In particular, ethanolic extracts of Cuminum cyminum L. and Propolis expressed MIC90 values of 0.075 mg/mL. The results show a significant in vitro effect of plant extracts against H. pylori that could be considered a valuable support in the treatment of the infection and may contribute to the development of new and safe agents for inclusion in anti-H. pylori regimens.

Anti-Bacterial Agents↗
PubMed1996

Role of the hypoglycemic plant extract cleome droserifolia in improving glucose and lipid metabolism and its relation to insulin resistance in fatty liver.

In this work the mechanism of the hypoglycemic effect of the plant Cleome-Droserifolia (C.d.) was studied in a group of albino rats rendered glucose intolerant by tetracycline (T.) induced fatty liver, and compared with a normal control (C.) rats. The plant extract significantly suppressed the rise in peripheral blood glucose concentrations, both in the basal (fasting) state and after glucose intake. Suppression of basal blood glucose indicated a lowering effect of the plant extract on hepatic glucose output (HGO). The postprandial hypoglycemic effect of the plant extract without increasing insulin secretion was explained by; First: Potentiation of peripheral and hepatic insulin sensitivity. Second: by diminishing intestinal glucose absorption, which was evident by blunting plasma glucose levels throughout the oral glucose challenge. This plant might prove to have a promising therapeutic value in the treatment of diabetes mellitus, for besides its postprandial hypoglycemic effect, its suppression to hepatic glucose output in the fasting state is a beneficial therapeutic finding in favour of the plant as insulin is the most important drug that brings about this effect. The plant has also got a hypocholesterolemic effect more specifically on low density lipoprotein cholesterol (LDL-C) which consequently raised the high density lipoprotein cholesterol/low density lipoprotein cholesterol (HDL-C/LDL-C) ratio. This adds to its value as a protective and antiatherogenic agent.

Animals↗
PubMed2005

Assays of physical stability and antioxidant activity of a topical formulation added with different plant extracts.

In the present investigation the changes on physical stability (pH, viscosity, flow index and tixotropy) of topical formulations were evaluated following inclusion of different plant extracts containing flavonoids. Also, the antioxidant effect of these plant extracts alone and after addition in the formulation was evaluated using chemiluminescence and the stable free radical 1,1-diphenyl-2-picrylhydrazyl (DPPH(.-)) assays, as well as the inhibition of lipid peroxidation. Formulation added with dl-alpha-tocopherol was used to compare the physical stability and antioxidant activity. Formulations with plant extracts showed pseudoplastic behavior with decreasing on viscosity and tixotropy. The Glycyrrhiza glabra (GG) and Ginkgo biloba (GB) extracts alone and the formulations containing these extracts showed great antioxidant and free radical scavenging activities while the other extracts studied (mixture of Glycyrrhiza glabra, Symphytum officinale L and Arctium majus root, Nelumbium speciosum and soybean) showed lower activity. The results suggest that GG and GB extracts may be used in topical formulations in order to protect skin against damage caused by free radical and reactive oxygen species.

Administration, Topical↗
PubMed2005

The estrogenic status and the COMT genotype of female blood donors influence the protective ability of the Mediterranean plant extracts against the hydrogen peroxide-induced DNA damage in lymphocytes.

The extent of oxidative DNA damage in lymphocytes can be used as a biomarker of the level of oxidative stress in the body. The comet assay has been widely used to measure such damage. The aim of our study was to evaluate: i) the extent of the oxidative DNA damage in lymphocytes isolated from blood of female donors taken in early and late follicular phases [low (LE) and high (HE) concentration of 17beta-estradiol, respectively], ii) the susceptibility of these lymphocytes to hydrogen peroxide exposure, and iii) the protective ability of five plant extracts against the hydrogen peroxide-induced DNA damage. The effect of the catechol-O-methytransferase genotype (wild COMT H/H and mutated homozygote COMT L/L) of female donors was also analyzed. The amount of endogenous DNA damage was higher in HE lymphocytes as compared with LE ones, independently of the genotype. When lymphocytes were stratified by COMT genotype, the level of DNA damage was higher in L/L donors. The protective effect of pretreatment with plant extracts (1 and 10 micro g/ml for 1 h) against the H(2)O(2) (25 microM, 5 min. at 4 degrees C)-induced oxidative DNA damage was observed only in H/H HE lymphocytes. In contrary, the plant extract pre-incubation enhanced the DNA damage in L/L HE lymphocytes. The plant extracts alone did not induce the DNA damage. The results showed that concentration of the circulating 17beta-estradiol influenced the extent of endogenous oxidative DNA damage while the beneficial or hazardous effects of the plant extracts might depend on the COMT genotype and the estrogen level.

Blood Donors↗
PubMed2005

Screening for the effects of natural plant extracts at different pH on in vitro rumen microbial fermentation of a high-concentrate diet for beef cattle.

Six natural plant extracts and three secondary plant metabolites were tested at five doses (0, 0.3, 3, 30, and 300 mg/L) and two different pH (7.0 and 5.5) in a duplicate 9 x 5 x 2 factorial arrangement of treatments to determine their effects on in vitro microbial fermentation using ruminal fluid from heifers fed a high-concentrate finishing diet. Treatments were extracts of garlic (GAR), cinnamon (CIN), yucca (YUC), anise (ANI), oregano (ORE), and capsicum (CAP) and pure cinnamaldehyde (CDH), anethole (ATL), and eugenol (EUG). Each treatment was tested in triplicate and in two periods. Fifty milliliters of a 1:1 ruminal fluid-to-buffer solution were introduced into polypropylene tubes supplied with 0.5 g of DM of a 10:90 forage:concentrate diet (15.4% CP, 16.0% NDF; DM basis) and incubated for 24 h at 39 degrees C. Samples were collected for ammonia N and VFA concentrations. The decrease in pH from 7.0 to 5.5 resulted in lower (P < 0.05) total VFA, ammonia N, branched-chain VFA concentration, acetate proportion, and acetate:propionate, and in a higher (P < 0.05) propionate proportion. The interaction between pH and doses was significant for all measurements, except for ATL and CDH for butyrate, ATL and EUG for acetate:propionate ratio, and ORE for ammonia N concentration. The high dose of all plant extracts decreased (P < 0.05) total VFA concentrations. When pH was 7.0, ATL, GAR, CAP, and CDH decreased (P < 0.05) total VFA concentration, and ANI, ORE, CIN, CAP, and CDH increased (P < 0.05) the acetate:propionate. The CIN, GAR, CAP, CDH, ORE, and YUC decreased (P < 0.05), and EUG, ANI, and ATL increased (P < 0.05) ammonia N concentration. The effects of plant extracts on the fermentation profile when pH was 7.0 were not favorable for beef production. In contrast, when pH was 5.5, total VFA concentration did not change (ATL, ANI, ORE, and CIN) or increased (P < 0.05) (EUG, GAR, CAP, CDH, and YUC), and the acetate:propionate (ORE, GAR, CAP, CDH, and YUC) decreased (P < 0.05), which would be favorable for beef production. Ammonia N (ATL, ANI, CIN, GAR, CAP, and CDH) and branched-chain VFA (ATL, EUG, ANI, ORE, CAP, and CDH) concentrations also were decreased (P < 0.05), suggesting that deamination was inhibited. Results indicate that the effects of plant extracts on ruminal fermentation in beef cattle diets may differ depending on ruminal pH. When pH was 5.5, GAR, CAP, YUC, and CDH altered ruminal microbial fermentation in favor of propionate, which is more energetically efficient.

Ammonia↗
PubMedDate not supplied

Use of the SOS-chromotest spot assay as a screening system for detecting genotoxic compounds in crude plant extracts.

An SOS-chromotest spot assay was used to detect genotoxic compounds in crude plant extracts. The method allows simultaneous testing of extracts from different species in either a liquid or a solid crystalline form. Extracts from two species of the genus Senna, native to the state of Morelos, Mexico, were assayed. Four genotoxic compounds were isolated, and were identified as quercetin and rutin from S. wislizeni, and 5,7-di- O-methylrutin and 5,7-di-O-methylquercetin from S. skinneri. The SOS-chromotest spot assay proved to be useful for activity- guided fractionation at the beginning of screening for genotoxic compounds in crude plant extracts.

Chemical Fractionation↗
PubMed2002

Cytotoxic and antiviral activities of Colombian medicinal plant extracts of the Euphorbia genus.

Forty-seven plant extracts of 10 species of the genus Euphorbia (Euphorbiaceae) used by Colombian traditional healers for the treatment of ulcers, cancers, tumors, warts, and other diseases, were tested in vitro for their potential antitumour (antiproliferative and cytotoxic) and antiherpetic activity. To evaluate the capacity of the extracts to inhibit the lytic activity of herpes simplex virus type 2 (HSV-2) and the reduction of viability of infected or uninfected cell cultures, the end-point titration technique (EPTT) and the MTT [3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide] colorimetric assay were used, respectively. The therapeutic index of the positive extracts for the antiviral activity was determined by calculating the ratio CC50 (50% cytotoxic concentration) over IC50 (50% inhibitory concentration of the viral effect). Five of the 47 extracts (11%) representing 3 out of 10 Euphorbia species (30%) exhibited antiherpetic action; the highest activity was found in the leaf/stem water-methanol extracts from E. cotinifolia and E. tirucalli. The therapeutic indexes of these two plant species were > 7.1; these extracts exhibited no cytotoxicity. Six extracts (13%) representing 4 plant species (40%) showed cytotoxic activity. The highest cytotoxicity was found in the dichloromethane extract obtained from E. cotinifolia leaves and the CC50 values for the most susceptible cell lines, HEp-2 and CHO, were 35.1 and 18.1 microgram/ml, respectively.

Animals↗
PubMed1992

Laboratory assessment of indigenous plant extracts for anti-juvenile hormone activity in Culex quinquefasciatus.

Of 15 plants tested, five plant extracts showed anti-juvenile hormone-like activity against laboratory colonised late fourth instar larvae and adult female mosquitoes. Petroleum ether extract of Eichhornia crassipes and acetone extracts of Ageratum conyzoides, Cleome icosandra, Tagetes erectes and Tridax procumbens showed growth inhibitory (P less than 0.001) and juvenile hormone mimicing activity to the treated larvae of C. quinquefasciatus.. Larval pupal intermediates, demalanised pupae, defective egg rafts and adult with deformed flight muscles were few noticeable changes. Biting behaviour was observed to be affected only in Ageratum, Cleome and Tridax extracts (P less than 0.001). Loss of fecundity was observed in the treated mosquitoes but no sterilant effects could be seen. Adults, obtained from larvae exposed to the plant extracts produced significantly shorter egg-rafts (P less than 0.005) than in control.

Animals↗
PubMed2006

SOS-red fluorescent protein (RFP) bioassay system for monitoring of antigenotoxic activity in plant extracts.

An optical antigenotoxicity assay using genetically engineered red fluorescent bacteria is presented. Exposure of Escherichia coli RS4U to genotoxicants [mitomycin C (MMC), nalidixic acid (NA) and hydrogen peroxide (HP)] resulted in phenotypic red fluorescence proportional to the concentration of the inducer. Except for tannic acid (TA), co-treatment of the genotoxicant-activated bacteria with ascorbic acid (AA) and aqueous plant extracts (Mangifera indica, Psidium guajava and Syzygium cumini) afforded protection against all three genotoxicants. TA was effective in suppressing the genotoxic effect of MMC and HP. The antigenotoxic effect is seen as inhibition of the genotoxicant-triggered red fluorescence. The IC50 of the plant extracts and AA varied with the genotoxicant used. Rec assay verified the antigenotoxic activity of the plant extracts. Folin-Ciocalteu test, FeCl3 test and DPPH assay confirmed the presence of polyphenolic compounds and hydrolyzable tannins in the plant extracts and the antioxidant capacity of the plant samples.

Antioxidants↗
PubMed1999

In vivo antimalarial activities of Quassia amara and Quassia undulata plant extracts in mice.

Extracts obtained from two Nigerian Simaroubaceae plants, Quassia amara L. and Quassia undulata (Giull and Perr) D. Dietr were screened for antimalarial properties using a total of six extracts. The plant extracts showed significant antimalarial activities in the 4 day suppressive in vivo antimalarial assay in mice inoculated with red blood cells parasitized with Plasmodium berghei berghei. Plant extracts were studied at 100 mg and 200 mg per kg body weight mouse per day, respectively. At a concentration of 100 mg/kg of mouse, Q. amara leaf hexane extract had the highest suppressive activity with a parasite density of 0.16 +/- 0.001%. Q. amara leaf methanol extract had an outstanding activity; of 0.05 +/- 0.03% at 200 mg/kg. Chloroquine (10 mg/kg, positive control) had a suppressive activity of 0.34 +/- 0.02 in the same assay on day 4.

Animals↗
PubMed2004

Effect of scoparia dulcis (Sweet Broomweed) plant extract on plasma antioxidants in streptozotocin-induced experimental diabetes in male albino Wistar rats.

Clinical research has confirmed the efficacy of several plants in the modulation of oxidative stress associated with diabetes mellitus. Scoparia dulcis plant extract is tried for prevention and treatment of diabetes mellitus induced experimentally by streptozotocin injection. A single dose of streptozotocin (45 mg/kg body weight) produced decrease in insulin, hyperglycemia, increased lipid peroxidation (Thiobarbituric reactive substances and lipid hydroperoxides) and decreased antioxidant levels (vitamin C, vitamin E, reduced glutathione, ceruloplasmin). Oral administration of an aqueous extract of Scoparia dulcis plant (200 mg/kg body weight) for 6 weeks to diabetic rats significantly increased the plasma insulin and plasma antioxidants and significantly decreased lipid peroxidation. The effect of Scoparia dulcis plant extract at 200 mg/kg body weight was better than that of glibenclamide, a reference drug.

Animals↗
PubMed2004

Influence of two plant extracts on broilers performance, digestibility, and digestive organ size.

A 42-d trial was conducted to study the influence of 2 plant extracts on performance, digestibility, and digestive organ weights in broilers. The feeding program consisted of a starter diet until 21 d and a finisher diet until 42 d. There were 4 treatment groups: control; 10 ppm avilamycin (AB); 200 ppm essential oil extract (EOE) from oregano, cinnamon, and pepper; and 5,000 ppm Labiatae extract (LE) from sage, thyme, and rosemary. No differences in feed intake or feed conversion were observed. From 14 to 21 d of age, broilers fed the LE diet grew faster than the broilers fed the control or EOE feeds (68.8 vs. 63.9 and 61.6 g/d, respectively). Antibiotic and plant extract supplementation improved apparent whole-tract and ileal digestibility of the nutrients. For starter feed, LE supplementation improved apparent fecal digestibility of DM (P < 0.01), and all additives increased ether extract digestibility (P < 0.001). However, no effect was detected for CP digestibility (P > 0.1). At the ileal level, the AB, EOE, and LE supplementation of the starter feed increased DM and starch (P < 0.01) digestibility but not CP digestibility (P > 0.1). All additives improved apparent fecal digestibility of DM and CP of the finisher diet. No differences were observed for proventriculus, gizzard, liver, pancreas, or large or small intestine weight. In the present study, both plant extracts improved the digestibility of the feeds for broilers. The effect of different additives on digestibility improved the performance slightly, but this effect was not statistically significant.

Animals↗