Search results for "leaves"
showing 10 items of 267 documents
Oleanolic acid and hederagenin glycosides from Weigela stelzneri
2015
Four previously undescribed and one known oleanolic acid glycosides were isolated from the roots of Weigela stelzneri, and one previously undescribed and three known hederagenin glycosides were isolated from the leaves. Their structures were elucidated mainly by 2D NMR spectroscopic analysis and mass spectrometry as 3-O-β-D-glucopyranosyl-(1 → 2)-[β-D-xylopyranosyl-(1 → 4)]-β-D-xylopyranosyl-(1 → 4)-β-D-xylopyranosyl-(1 → 3)-α-L-rhamnopyranosyl-(1 → 2)-α-L-arabinopyranosyloleanolic acid, 3-O-β-D-glucopyranosyl-(1 → 2)-[β-D-xylopyranosyl-(1 → 4)]-β-D-xylopyranosyl-(1 → 4)-β-D-xylopyranosyl-(1 → 3)-α-L-rhamnopyranosyl-(1 → 2)-β-D-xylopyranosyloleanolic acid, 3-O-β-D-glucopyranosyl-(1 → 2)-[β-…
New amide and dioxopiperazine derivatives from leaves of Breynia nivosa
2017
The first chemical investigation of leaves of Breynia nivosa from Nigeria resulted in the isolation of two new amide derivatives breynivosamides A and B (1 and 2) and two new dioxopiperazine derivatives breynivosines A and B (4 and 5) together with seven known compounds (3, 6-11). The structures of the new compounds were elucidated by 1D, 2D NMR and HRESIMS data as well as by comparison with the literature. All isolated compounds were tested for the cytotoxic and antimicrobial activities. Only cristatin A (6) showed cytotoxicity against the L5178Y mouse lymphoma cell line with an IC50 value of 13.9μM while breynivosamide A (1) exhibited moderate antimicrobial activity against Mycobacterium …
Two New Glycosides from Astragalus caprinus
2001
A new glycoside of flavonol (1) and a new glycoside of a cycloartane-type triterpene (2) were isolated from the leaves and the roots of Astragalus caprinus, respectively. Their structures were elucidated in turn by spectroscopic data interpretation as 3-O-[[beta-D-xylopyranosyl(1-->3)-alpha-L-rhamnopyranosyl(1-->6)][beta-D-apiofuranosyl(1-->2)]]-beta-D-galactopyranosyl kaempferol (1) and 3-O-(beta-D-xylopyranosyl)-24-O-(beta-D-glucopyranosyl)-20,25-epoxycycloartane-3beta,6alpha,16beta,24alpha-tetrol (2).
Application of hull, bur and leaf chestnut extracts on the shelf-life of beef patties stored under MAP: Evaluation of their impact on physicochemical…
2018
The impact of chestnut extracts (Castanea sativa) from leaf, bur and hull at different concentrations on the shelf-life of beef patties during 18 days of refrigerated storage at (2 ± 1 °C) was studied and compared to control and synthetic antioxidant (BHT) samples. Total phenolics and in vitro antioxidant capacity of extracts were evaluated by using DPPH, FRAP, reducing power and oil accelerated oxidation test (peroxide value, conjugated dienes, p-anisidine and fatty acid profile). The microbial spoilage, colour parameters, lipid oxidation and sensorial properties were used to assess antioxidant activity in beef patties. The highest total phenolic content was found in bur extracts (43.68 ± …
Anti-inflammatory and antioxidant activities of Jungia paniculata.
2010
The present study was conducted to evaluate the antioxidant and anti-inflammatory activities of Jungia paniculata (DC.) A. Gray (Asteraceae), used traditionally in Peru. The dry leaves were extracted with methanol, 50% methanol, and water. The anti-inflammatory activity of this plant was studied using in vitro (nitric oxide production in RAW 264.7 macrophages and sPLA(2) inhibition assay) and in vivo (carrageenan-induced paw edema in rats and TPA-induced ear edema in mice) model systems. The antioxidant activity of extracts was studied using three in vitro model systems (DPPH(*) radical-scavenging assay, ABTS(*+) assay, and superoxide radical-scavenging activity). The results have been corr…
Unexplained chronic liver disease in Ethiopia: a cross-sectional study
2018
Background Hepatitis B virus (HBV) infection is assumed to be the major cause of chronic liver disease (CLD) in sub-Saharan Africa. The contribution of other aetiological causes of CLD is less well documented and hence opportunities to modulate other potential risk factors are being lost. The aims of this study were to explore the aetiological spectrum of CLD in eastern Ethiopia and to identify plausible underlying risk factors for its development. Methods A cross-sectional study was undertaken between April 2015 and April 2016 in two public hospitals in Harar, eastern Ethiopia. The study population comprised of consenting adults with clinical and radiological evidence of chronic liver dise…
Phospholipid breakdown and choline release under hypoxic conditions: inhibition by bilobalide, a constituent of Ginkgo biloba
1997
A marked increase of choline release from rat hippocampal slices was observed when the slices were superfused with oxygen-free buffer, indicating hypoxia-induced hydrolysis of choline-containing phospholipids. This increase of choline release was suppressed by bilobalide, an ingredient of Ginkgo biloba, but not by a mixture of ginkgolides. The EC50 value for bilobalide was 0.38 microM. In ex vivo experiments, bilobalide also inhibited hypoxia-induced choline release when given p.o. in doses of 2-20 mg/kg 1 h prior to slice preparation. The half-maximum effect was observed with 6 mg/kg bilobalide. A similar effect was noted after p.o. administration of 200 mg/kg EGb 761, a ginkgo extract con…
Antinociceptive and anti-inflammatory activities of Acacia pennata wild (Mimosaceae)
2005
The butanolic fraction of dried leaves of Acacia pennata (Mimosaceae) was tested for analgesic and anti-inflammatory activities in animal models. It showed significant protective effects against chemical stimuli (acetic acid and formalin) in the mouse. It also produced a significant increase of the threshold of sensitivity to pressure-induced pain in the rats. The extract revealed an inhibitory effect in carrageenin-induced rat paw oedema in the late phase. The results suggested that a peripheral mechanism is involved in the analgesic, associated to anti-inflammatory effect (NSAIDs-like). Among the class of compounds characterized in this fraction, flavonoids may be mainly responsible for t…
Host sex discrimination by an egg parasitoid on Brassica leaves.
2011
Egg parasitoids are able to find their hosts by exploiting their chemical footprints as host location cues. In nature, the apolar epicuticular wax layer of plants that consists of several classes of hydrocarbons serves as the substrate that retains these contact kairomones. However, experiments on chemical footprints generally have used filter paper as substrate to study insect behavior. Here, we explored the ability of Trissolcus basalis (Scelionidae) females to discriminate between footprint cues left by male and female Nezara viridula (Pentatomidae) on leaves of their host plant Brassica oleracea (broccoli). Furthermore, we analyzed the chemical composition of the outermost wax layer of …
Ethnobotanical survey and cytotoxicity testing of plants of South-western Nigeria used to treat cancer, with isolation of cytotoxic constituents from…
2010
Abstract Ethnopharmacological relevance There is only scant literature on the anticancer components of medicinal plants from Nigeria, yet traditional healers in the area under study claim to have been managing the disease in their patients with some success using the species studied. Aim of study To document plants commonly used to treat cancer in South-western Nigeria and to test the scientific basis of the claims using in vitro cytotoxicity tests. Methods Structured questionnaires were used to explore the ethnobotanical practices amongst the traditional healers. Methanol extracts of the most common species cited were screened for cytotoxicity using the sulforhodamine B (SRB) assay in both…