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Obesity is a multifactorial problem that leads to several life-threatening diseases and is becoming one of the most important public health problems with huge social costs. The incidence of obesity is increasing at an alarming rate, so the discovery of natural products that counteracts obesity with the least side effects has become of extreme importance nowadays. Inhibition of digestive enzymes is one of the most widely studied mechanisms used to determine the potential efficacy of anti-obesity agents. To that effect, the total methanolic and aqueous extracts of five plants [viz: Caralluma quadrangula, Caralluma tuberculata, Hibiscus shizopetalous, Hibiscus subdariffa (white variety) and Solenostemma argel] were tested for their inhibitory activity against pancreatic lipase, α-amylase and α-glucosidase, along with their anti-oxidant potential via two different complementary methods; DPPH (1, 1-Diphenyl-2-picrylhydrazyl) radical scavenging activity and iron reducing power assays. The plants' extracts were also estimated quantitatively for their total phenolic, flavonoid, tannin and steroidal contents. The results showed that Solenostemma argel was the most active among the selected plants. An optimized extraction method was developed for S. argel based on its enzyme inhibitory activity to ensure maximum biological activity. The methylene chloride and n-butanol fractions in addition to seven isolated compounds viz: sterols, pregnane glycoside and flavonoid aglycones and glycosides from S. argel were further evaluated. Consequently, the present study suggests that S. argel could be of therapeutic interest for the control of obesity.

The phytochemical investigation of Ochrosia eliptica leaves resulted in isolation and identification of eight compounds; lupeol, lupeol acetate, uvaol, ursolic acid, β-sitosterol glucoside, rutin, 8-methoxy and 9-methoxy ellipticine . The ethanolic extract and fractions were studied for their cytotoxic, antioxidant and anti-inflammatory activities. The cytotoxic activity was performed on human mammary adenocarcinoma (MCF7), its multidrug-resistant ‎ counterpart (VCREMS), estrogen receptor negative human metastatic breast ‎ adenocarcinoma cells (MDA-MB-231) and the non-cancerous, immortalized by ‎ telomerase, human breast epithelial cell line (hTERT-HME1). Additionally, the inhibitory potential on Cdc25s proteins was determined. The results showed that the dichloromethane (DCM) fraction and the major alkaloid; 9-methoxyellipticine exhibited high inhibitory activity against all tested cell lines particularly MCF7 and VCREMS cell lines, whereas t he DCM fraction showed a significant inhibitory action on Cdc25 A isoform. In contrast, the n-butanol fraction and 9-methoxyellipticine displayed the highest antioxidant potential. The DCM fraction showed significant anti-inflammatory activity compared to indomethacin. This work comprises the first comprehensive work to be conducted on O. elliptica leaves showing its potential in multiple biological activities .

The effects of six biotic and abiotic elicitors, i.e. MeJA (methyl jasmonate), SA (salicylic acid), ZnCl2, glutathione and β-glucan BG (fungal elicitor), and wounding, on the secondary metabolite accumulation in the soft coral Sarcophyton ehrenbergi were assessed. Upon elicitation, metabolites were extracted and analysed by ultra-performance liquid chromatography-mass spectrometry (UPLC-MS). Except for MeJA, no differences in photosynthetic efficiency were observed after treatments, suggesting the absence of a remarkable stress on primary production. Chemometric analyses of UPLC-MS data showed clear segregation of SA and ZnCl2 elicited samples at 24 and 48 h post elicitation. Levels of acetylated diterpene and sterol viz., sarcophytonolide I and cholesteryl acetate, was increased in ZnCl2 and SA groups, respectively, suggesting an activation of specific acetyl transferases. Post elicitation, sarcophytonolide I level increased 132 and 17-folds at 48 h in 0.1 mM SA and 1 mM ZnCl2 groups, respectively. Interestingly, decrease in sarcophine, a major diterpene was observed only in response to ZnCl2, whereas no change was observed in sesquiterpene content following treatments. To the best of our knowledge, this study provides the first documentation for elicitation effects on a soft corals secondary metabolome and suggests that SA could be applied to increase diterpenoid levels in corals.

In this work both kinetic and thermodynamics of castor oil extraction from its seeds using subcritical water technique were studied. It was found that the extraction process followed two consecutive steps. In these steps, the oil was firstly extracted from inside the powder by diffusion mechanism. Then the extracted oil, due to extending the extraction time under high temperature and pressure, was subjected to a decomposition reaction following first order mechanism. The experimental data correlated well with the irreversible consecutive unimolecular-type first order mechanism. The values of both oil extraction rate constants and decomposition rate constants were calculated through non-linear fitting using DataFit software. The extraction rate constants were found to be 0.0019, 0.024, 0.098, 0.1 and 0.117 min(-1), while the decomposition rate constants were 0.057, 0.059, 0.014, 0.019 and 0.17 min(-1) at extraction temperatures of 240, 250, 260, 270 and 280°C, respectively. The thermodynamic properties of the oil extraction process were investigated using Arrhenius equation. The values of the activation energy, Ea, and the frequency factor, A, were 73 kJ mol(-1) and 946, 002 min(-1), respectively. The physicochemical properties of the extracted castor oil including the specific gravity, viscosity, acid value, pH value and calorific value were found to be 0.947, 7.487, 1.094 mg KOH/g, 6.1, and 41.5 MJ/Kg, respectively. Gas chromatography analysis showed that ricinoleic acid (83.6%) appears as the predominant fatty acid in the extracted oil followed by oleic acid (5.5%) and linoleic acid (2.3%).

Celtis australis L. and Celtis occidentalis L. are deciduous ornamental trees, grown in Egypt. This study presents a comparative investigation of the botanical features of the stems, stem barks and leaves of both plants. Furthermore, the DNA of both plants was extracted from leaf samples and analyzed using 10 decamer random primers. A total of 159 random amplified polymorphic DNA (RAPD) markers were identified. Seed protein profiling was also performed and revealed low variation in both plants’ SDS–PAGE profiles.

A major development over the past two decades has been the realization that free radical induced lipid peroxidation and DNA damage are associated with major health problems, e.g. cancer and ageing. Plant-derived antioxidants are increasingly found beneficial in protecting against these diseases. Celtis australis L. and Celtis occidentalis L. are two plants that have a variety of uses in folk medicine but have not been evaluated before for their antioxidant and cytotoxic properties. Therefore, the extracts of both plants' leaves were investigated for these activities, as well as isolation of the bioactive compounds responsible for the activities. Molecular structures of the compounds were elucidated by UV, HRESIMS, 1D ((1)H and (13)C) and 2D ((1)H-(13)C HSQC and (1)H-(13)C HMBC) NMR analyses. The ethanolic and aqueous extracts, n-butanol fractions and the isolated major compound were tested for their antioxidant activity using DPPH radical scavenging assay, xanthine oxidase-induced generation of superoxide radical and lipid peroxidation assay by thiobarbituric acid-reactive substances (TBARS) method using rat tissue homogenates. Cytotoxic activities were studied using standard MTT assay. A novel flavonoid C-triglycoside, 4‴-α-rhamnopyranosyl-2″-O-β-d-galactopyranosylvitexin, was isolated from both plants' leaves, together with seven known flavonoids. The n-butanol fractions and the major compound 2″-O-β-galactopyranosylvitexin showed significant antioxidant activities, more pronounced than the tested standards BHT and dl-α-tocopherol in most tests. All extracts showed variable cytotoxic activities. This study provides strong evidence for the antioxidant and cytotoxic activities of the extracts of Celtis australis L. and Celtis occidentalis L. leaves, which were attributed to the polar n-butanol fractions and the major isolated flavonoid 2″-galactosylvitexin.

Two novel acylated flavonol glycosides were isolated from the n-butanol fraction of the ethanolic extract of Platanus orientalis L. leaves. They were identified as kaempferol-3-O-(2″’-p-E-coumaroylrhamnosyl)(1″’→6″)-[β-D-glucopyranosyl-(1′″→2″)-β-D-glucopyranoside]-7-O-α-L-rhamnopyranoside, and quercetin-3-O-(2″’-p-E-coumaroylrhamnosyl)(1″’→6″)-[β-D-glucopyranosyl-(1″″→2″)-β-D-glucopyranoside]-7-O-α-L-rhamnopyranoside. Their structures were established on the basis of detailed spectral analysis.

A new flavonoid glycoside, 5,7,4′-trihydroxy-3,6-dimethoxyflavone-3′- O-β-D-xylopyranoside (axillarin-3′- O-β-D-xylopyranoside), was isolated from the ethyl acetate fraction of the ethanolic extract of Platanus orientalis L. leaves, along with nine known flavonoid aglycones and glycosides, a phenolic acid and a phenolic acid derivative. Their structures were established on the basis of detailed spectral analysis. The total ethanolic, aqueous and ethyl acetate extracts of the leaves were tested for antihepatotoxic, antioxidant and cytotoxic activities. The extracts were found to be effective in protection against CCl4liver injury by significantly lowering alanine aminotransferase (ALT), aspartate aminotransferase (AST) and alkaline phosphatase (ALP) levels. The extracts also significantly restored depleted levels of glutathione, indicating a strong antioxidant activity, while they showed variable cytotoxic activity.