Comparative phytochemical composition, oleuropein quantification, antioxidant and cytotoxic properties of Olea europaea L. leaves.

In the present research, oleuropein (OLE) contents from two Saudi Arabian wild olive trees (Olea europaea L.) leaves (O1 and O2), were collected from two nearby geographical sites differing in altitudes, and were determined via UHPLC-MS analysis. Moreover, total bioactive contents, antioxidant, and cytotoxicity (against MCF-7 and MDA-MB-231 cells) potential were also evaluated. The sample (O2) was found to contain significantly (p < 0.05) higher OLE content (4.13 ± 1.0 mg/g DW) compared with the sample (O1) having OLE content (3.63 ± 1.1 mg/g DW). A similar trend was observed regarding total bioactive contents and antioxidant potential. However, both samples exhibited low cytotoxicity against tested cell lines. Furthermore, with hierarchical cluster analysis that compared the results of our samples (O1 and O2) to other samples reported in the literature, it was found that the variance in OLE content and biological activities from Al Baha region leaves had a resemblance to other reported superior cultivars.

Bioassay-Guided Isolation and in Silico Study of Antibacterial Compounds From Petroleum Ether Extract of Peperomia blanda (Jacq.) Kunth.

Bioassay-guided isolation protocol was performed on petroleum ether extract of Peperomia blanda (Jacq.) Kunth using column chromatographic techniques. Five compounds were isolated and their structures were elucidated via one-dimensional (1D) and two-dimensional (2D) NMR, gas chromatography mass sectroscopy (GCMS), liquid chromatography mass spectroscopy (LCMS), and ultraviolet (UV) and infrared (IR) analyses. Dindygulerione E (a new compound), and two compounds isolated from P. blanda for the first time-namely, dindygulerione A and flavokawain A-are reported herein. Antimicrobial activity was screened against selected pathogenic microbes, and minimum inhibitory concentrations (MIC) were recorded within the range of 62-250 µg/mL. Assessment of the pharmacotherapeutic potential has also been done for the isolated compounds, using the Prediction of Activity spectra for Substances (PASS) software, and different activities of compounds were predicted. Molecular docking, molecular dynamics simulation and molecular mechanics/Poisson-Boltzmann Surface Area (MM-PBSA) calculations have proposed the binding affinity of these compounds toward methylthioadenosine phosphorylase enzyme, which may explain their inhibitory actions.

Ethnopharmacological Survey of Medicinal Plants in Albaha Region, Saudi Arabia.

BACKGROUND: Local natural medicinal resource knowledge is important to define and elaborate usage of herbs, in systematic and organized manner. Until recently, there has been little scientifically written document regarding the traditional uses of medicinal plants in Al Bahah region. OBJECTIVE: This pilot study aims to collect the ethnobotanical information from native populations regarding the benefits of medicinal plants of Al Bahah region, and determine if the traditional usage is scientifically established (proved) from literature. MATERIALS AND METHODS: The survey collected data for 39 plant species recorded by informants for their medicinal benefits. The recorded species were distributed among 28 plant families. Leguminosae and Euphorbiaceae were represented each by 3 species, followed by Asteraceae (2 species), Lamiaceae (2 species), Apocynaceae (2 species), and Solanaceae (2 species). All the medicinal plants were reported in their local names. Analysis of ethnopharmacological data was done to obtain percentage of plant families, species, parts of plants used, mode of administration, and preparation types. RESULTS: Total 43 informants were interviewed, maximum number of species were used to cure skin diseases including burns (3), wounds (7), warts (1), Leishmania (7), topical hemostatic (2), followed by gastrointestinal system, rheumatism, respiratory tract problems, diabetes mellitus, anti-snake venom, malaria, and eye inflammation. CONCLUSIONS: The study covered Al Bahah city and its outskirts. Ten new ethnobotanical uses were recorded such as antirheumatic and anti-vitiligo uses for Clematis hirsute, leishmaniasis use of Commiphora gileadensis, antigout of Juniperus procera, removing warts for Ficus palmata. SUMMARY: 39 plant species from 28 plant families are used for treating more than 20 types of diseases.Maximum number of species (23 species) was used for treating skin diseases (42.6%) including leishmaniasis, wound healing, dermatitis, psoriasis, vitiligo and warts.Ten ethnobotanical uses of 8 studied plants have not been previously reported.The most used medicinal plants, according to their Use Index (UI) were Juniperus procera, Rumex nervosus, and Ziziphus spina-christi. Abbreviations Used: UI : Use Index, GI: Gastrointestinal tract, RD: Rheumatic disease, CVS: Cardiovascular diseases, UTI: Urinary tract infection, DM: Diabetes mellitus, RT: Respiratory infection, KSA: Kingdom of Saudi Arabia.

Variations in Essential Oil Compositions of Lavandula pubescens (Lamiaceae) Aerial Parts Growing Wild in Yemen.

Lavandula pubescens Decne. is one of five Lavandula species growing wild in Yemen. The plant is used in Yemeni traditional medicine, and the essential oil tends to be rich in carvacrol. In this work, L. pubescens was collected from eight different locations in Yemen, the essential oils obtained by hydrodistillation, and the oils analyzed by gas chromatography/mass spectrometry (GC/MS). Principal component analysis (PCA) and hierarchical cluster analysis (HCA) were used to differentiate between the L. pubescens samples. The essential oils were rich in carvacrol (60.9 - 77.5%), with lesser concentrations of carvacrol methyl ether (4.0 - 11.4%), caryophyllene oxide (2.1 - 6.9%), and terpinolene (0.6 - 9.2%). The essential oil compositions in this study showed very high similarity, but it was possible to discern two separate groups based on minor components, in particular the concentrations of terpinolene, carvacrol methyl ether, m-cymen-8-ol, and caryophyllene oxide.

Nematicidal and antimicrobial activities of methanol extracts of 17 plants, of importance in ethnopharmacology, obtained from the Arabian Peninsula.

AIM/BACKGROUND: The development of resistance to synthetic drugs by target organisms is a major challenge facing medicine, yet locked within plants are phytochemicals used in herbal medicine (especially in the Arabian Peninsula) that may find application in this regard. In pursuit of unlocking these "hidden treasures," the methanol extracts of leaves, aerial parts, fruits, and resins of 17 plants used in the Arabian Peninsula were screened for antimicrobial activities. MATERIALS AND METHODS: The nematicidal, antibacterial, and antifungal activities were determined using appropriate assays. Steinernema feltiae, Staphylococcus carnosus, Escherichia coli, and Saccharomyces cerevisiae were used as test organisms. Concentrations of the extracts ranging from 0.5 to 20 mg/ml were tested and appropriate statistical tests performed on the data generated. RESULTS: The results show that extracts from Solanum incanum, Chenopodium murale, Commiphora myrrha, Anthemis nobilis, and Achillea biebersteinii were the most active and had very high activities against two or more of the test organisms at low concentrations. Extracts of the leaves of S. incanum and resins of Ferula asafoetida were the most active nematicides, with significant activity at 0.5 mg/ml. Extracts of C. myrrha and C. murale had the most active antibacterial activity with inhibition zones of 12-15 mm and minimum inhibitory concentrations (MICs) of 2.5 mg/ml for both bacteria. Extracts of the leaves of A. biebersteinii were the most active fungicide, giving an MIC of 1.5 mg/ml. CONCLUSION: The results validate the use of these plants in ethnopharmacology, and open new vistas of opportunities for the development of cheap but effective agents that may be useful against infectious diseases.

Anticholinesterase activity of endemic plant extracts from Soqotra.

A total of 30 chloroform and methanol extracts from the following endemic Soqotran plants Acridocarpus socotranus Olive, Boswellia socotranao Balf.fil, Boswellia elongata Balf. fil., Caralluma socotrana N. Br, Cephalocroton socotranus Balf.f, Croton socotranus Balf. fil.., Dendrosicycos socotrana Balf.f., Dorstenia gigas Schweinf. ex Balf. fil., Eureiandra balfourii Cogn. & Balf. fil., Kalanchoe farinaceae Balf.f, Limonium sokotranum (Vierh) Radcl. Sm), Oldenlandia pulvinata, Pulicaria diversifolia (Balf. and Pulicaria stephanocarpa Balf. were screened for their acetylcholinesterase inhibitory activity by using in vitro Ellman method at 50 and 200 µg/ml concentrations. Chloroform extracts of Croton socotranus, Boswellia socotrana, Dorstenia gigas, and Pulicaria stephanocarpa as well as methanol extracts of Eureiandra balfourii exhibited inhibitory activities higher than 50 % at concentration of 200 µg. At a concentrations of 50 µg, the chloroform extract of Croton socotranus exhibited an inhibition of 40.6 %.