Miriam F. Yousif

Large-scale in Vitro. Screening of Egyptian Native and Cultivated Plants for Schistosomicidal Activity

Abstract In vitro. bioassay screening of 346 methanol extracts originated from 281 native and cultivated plant species growing in Egypt, and related to 81 families, was carried out for schistosomicidal activity. The extracts were bioassayed at 100 µg/mL on viable Schistosoma mansoni. mature worms in culture medium. Viability of worms was examined after exposure for 24 h, and mortality determined. Negative (DMSO) and positive (praziquantel) controls were used. Of the tested plant extracts, 72 were found to possess reproducible in vitro. antischistosomal activity. These active extracts were further subjected to determination of their LC50 and LC90 values. Strong antischistosomal activity was found in the extracts of 15 species (possessing LC50 ≤ 15 µg/mL), viz. Agave americana. L. var. marginata. Trel. (Agavaceae), A. lophantha. Schiede (Agavaceae), Furcraea selloa. C.Koch. (Agavaceae), Calotropis procera. (Aiton) W.T.Aiton (Asclepiadaceae), Pergularia tomentosa. L. (Asclepiadaceae), Asclepias sinaica. (Boiss.) Muschl. (Asclepiadaceae), Alkanna orientalis. (L.) Boiss. (Boraginaceae), Khaya grandifoliola. DC. (Meliaceae), Swietenia mahogani. (L.) Jacq. (Meliaceae), Pimenta racemosa. (Mill.) J.W.Moore (Myrtaceae), Pinus canariensis. C.Sm. (Pinaceae), Verbascum sinaiticum. L. (Scrophulariaceae), Solanum elaeagnifolium. Cav. (Solanaceae), S. nigrum. L. (Solanaceae), and Brachychiton rupestris. (Lindl.) K.Schum. (Sterculiaceae). These 15 species could represent promising bioactive sources that deserve further investigation, with the aim of finding novel antischistosomal agents. The current study represents the first report on a systematic screening of schistosomicidal activity utilizing a large number of plant species.

Bioactive constituents from Harpephyllum caffrum Bernh. and Rhus coriaria L.

Background: The leaf ethanol extract of Harpephyllum caffrum Bernh. has evidenced medicinal value due to its hepatoprotective activity. It demonstrated inhibitory effects on test standard microbes approximated to 40% the potency of ofloxacin and fluconazole. The same extract evidenced in vitro cytotoxicity on human cell lines, liver carcinoma HEPG2, larynx carcinoma HEP2, and colon carcinoma HCT116 cell lines when compared to doxorubicin. Materials and Methods: Fractionation of the leaf ethanol extract led to the isolation of the polyphenols, ethyl gallate, and quercetin-3-O-rhamnoside, a hydrocarbon, hendecane, the fatty acid ester, methyl linoleate, and four triterpenoids, betulonic acid, 3-acetyl-methyl betulinate, lupenone and lupeol for the first time, in addition to the previously reported phenol acids and flavonoids, gallic acid, methyl gallate, quercetin, kaempferol, kaempferol-3-O-rhamnoside, kaempferol-3-O-galactoside, apigenin-7-O-glucoside, and quercetin-3-O-arabinoside. Results: The ethanol extract of the fruit of the genetically related Rhus coriaria L., known as sumac, afforded protocatechuic acid, isoquercitrin, and myricetin-3-O-α-L-rhamnoside from the fruits for the first time, in addition to the previously reported phenol acids and flavonoids, gallic acid, methyl gallate, kaempferol, and quercetin. Conclusion: The leaf ethanol extract of H. caffrum Bernh. exhibited variable anti-inflammatory, analgesic, and antipyretic activities, besides the hepatoprotective, in vitro cytotoxic and anti-microbial activities.

Seasonal Variation in the Essential Oil Composition of Origanum majorana L. Cultivated in Egypt

Z. Naturforsch. 64 c, 611 - 614 (2009); received March 1/30, 2009 The hydrodistilled essential oil content of Origanum majorana L. (Lamiaceae) ranged from 2.5 - 3% with the maximal value (3%) in spring. Analysis of the oil by GC/MS resulted in the identifi cation of 15, 15, 11, and 14 components in the oils prepared in spring, summer, autumn, and winter, respectively. The composition of the essential oils differed quantitatively and qualitatively according to the time of collection. Thymol (38.4%) and cis-sabinene hydrate (25.3%) were the major components in spring plants. Terpinen-4-ol (37.4%, 20.5%, 16.3%) was a major component in the summer, autumn and winter oils, respectively. cis- Sabinene hydrate (54.4%) was major in winter plants while terpinolene (43.1%) was the main component in autumn plants. Other components detected in lower amounts in all oil samples were sabinene and p-cymene (up to 7.4% and 13.9% in autumn), and α-terpinene (up to 13.3% in summer)

Composition and Bioactivities of the Essential Oil from Leaves of Lippia citriodora Kunth Cultivated in Egypt

Abstract Analysis of the hydrodistilled essential oil from the fresh leaves of Lippia citriodora Kunth (Verbenaceae), cultivated in Egypt at two different growth stages, by gas chromatography-mass spectrometry (GC-MS) resulted in the identification of 22 and 25 components in the oils prepared during the vegetative (June) and flowering (October) stages, respectively. The composition of the essential oils differed quantitatively and qualitatively according to the time of collection. The four major detected constituents (neral, geranial, dl-limonene and α-curcumene) exhibited remarkable differences between the two stages. Total percentage of oxygenated monoterpene aldehydes, represented by neral and geranial, decreased from 41.2 % to 35.2 % in June and October, respectively. On the other hand, the percentage of α-curcumene increased from 5.6 % to 14.5 %, while dl-limonene, the major monoterpene hydrocarbon was found only in June (10.6 %). The essential oil exhibited variable anti-inflammatory, antipyretic, analgesic and antioxidant properties. It also showed a moderate antibacterial activity.

Vicia ervilia L. seeds newly explored biological activities

Abstract Within the global context of increasing poverty in the developing countries, natural products are important in devising new drugs. Vicia ervilia L. Willd., unlike several fabaceae seeds, is not used for human consumption till now. We aim to discover any possible medicinal use of the seed. Analgesic, anti-inflammatory, antiulcerogenic and antihyperglycemic activities were evaluated using hot plate, carrageenan-induced rat paw edema, ethanol-induced ulcer model and alloxan-induced diabetes methods, respectively. Antiviral activity was evaluated using Methylthiazol Tetrazolium assay. V. ervilia seeds ethanol (70%) extract had significant anti-inflammatory, analgesic, antiulcerogenic, antihyperglycemic and antiviral activities. It is of excellent choice for treatment of several illnesses in developing countries due to its diverse resource, easy accessibility, affordability and its newly proved significant wide range of biological activities.

Formulation and Evaluation of Two Anti-inflammatory Herbal Gels

Abstract Two herbal gels expected to produce a topical anti-inflammatory activity were formulated, characterized and evaluated both phytochemically and biologically. The selected active ingredients were two tannin extracts (Q and G) obtained from Acacia nilotica Del. fruits (Qarad) and Quercus infectoria Oliv. galls (Oak gall). The total polyphenol content of the powdered drugs was estimated colorimetrically. The aqueous methanol (50 %) extracts of the investigated samples were individually incorporated, at different concentrations (0.5 – 2 mg/ml), into polyvinyl alcohol (PVA) hydrogels. Gallic acid was used as marker for HPLC standardization of the extracts and determination of drug content in the hydrogels. The anti-inflammatory activity was assessed by measuring the inhibitory effect of the extracts and hydrogels on xylene-induced ear edema in mice.