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Chemists and industrialists are continuously attempting to develop greener and more environmentally benign chemical processes to extract essential oils and bioactive metabolites of high purity, finding various applications in cosmetics, detergents, nutraceuticals and pharmaceuticals. An increase preferenced for natural products over synthetic ones has made supercritical fluid technology a primary alternative for the generation of high-value bioactive ingredients. This effective technique requires only moderate temperatures, eliminates clean-up steps and avoids the use of harmful organic solvents. In this context, our study was focused on the chemical analysis of Calamintha nepeta subsp. nepeta aromatic extracts obtained with supercritical carbon dioxide. The effect of different operating conditions on the capacity of the lipophilic solvent to extract the targeted volatile components was also studied. The process was carried out at a fairly low constant temperature of 40°C, and with varying the pressure from 90 to 300 bar. The chemical composition of the extracts was analyzed by gas chromatography-mass spectroscopy. The results showed that the composition pattern, the concentrations of individual components and the quality of the extractable analytes were affected by pressure increase. The extraction yields varied from 0.73 to 1.21 wt% at 90 and 300 bar, respectively., (© 2020 John Wiley & Sons, Ltd.)

Background: Natural products, whether pure compounds or standardized plant extracts, offer unlimited opportunities for other drug sources due to the unequaled availability of chemical diversity. Stinging Nettle (Urtica dioica) is a unique herbaceous perennial flowering plant with stinging hairs. The leaf extract of nettle was one of the herbal remedies which the experimental, clinical and trials have complemented each other. It is a very well-known plant with a wide historical background use of stems, leaves and roots. It has a long history of use as power sources such as soup or curry, and also used as fiber and a medicinal plant. Urtica dioica has traditionally been used in the control of cardiovascular disorders especially hypertension. The leaf extract of Urtica dioica has been reported to improve glucose homeostasis in vivo. Nettle root could prevent some of the effects of prostatic hyperplasia. Extracts of nettle leaf are used as anti-inflammatory remedies for rheumatoid arthritis. Urtica dioica extract significantly increased the sensitivity of breast cancer cells to paclitaxel. This article aims to review the very wide ranging of pharmacological effects of Urtica dioica extract., Methods: Articles on PuBmed between 1980 and 2019., Results: Description and critical review of the pharmacological effects of Urtica dioica and other uses., Conclusion: The nettle is actually a plant with many qualities and uses. The interest in it is deserved and it is given by other studies and investigations., (Copyright © 2019 Elsevier Ltd. All rights reserved.)

Cynara scolymus L. (Artichoke) has been used for the treatment of metabolic disorders. The purpose of the present study was to investigate the hepatoprotective effect of Cynara scolymus leaves extract against a high fat diet (HFD) induced rats. This study investigated the most abundant phenolic compounds rich Cynara scolymus leaves extract and it is antihypercholesterolemic and antioxidative effects in vivo . The hypercaloric high fat diet (HFD) was treated with 200 mg/kg and 400 mg/kg of ethanol extract (EEA) from leaves of Cynara and atorvastatin (ATOR) (10 mg/kg/day) during an 8-week period. Lipid profile was measured and oxidative stress systematic in hepatic tissue was determined. Our data revealed that HFD-induced hepatic dysfunction manifested by significant abnormal levels of AST, ALT, ALP, LDH, and OCT was accompanied by increasing levels of oxidative stress biomarker (ROS, MDA, and AOPP) while decreasing in antioxidant status. Coadministration of EEA significantly reduced serum lipid profile and hepatic disorders which was confirmed to be histological by reducing the fatty liver deposition in hepatic lobule. These findings suggest that Cynara leaves exert antiobesity and antioxidant liver effects in HFD-induced obese rats.

Background: Diabetes mellitus (DM) is associated with hyperglycemia, inflammatory disorders and abnormal lipid profiles, currently the extracts from leaves of cynara scolymus has been discovered to treat metabolic disorders and has been stated by multitudinous scientists according to a good source of polyphenols compounds. The present study aimed to evaluate the protective effect of the ethanol leaves extract of C. scolymus in alloxan induced stress oxidant, hepatic-kidney dysfunction and histological changes in liver, kidney and pancreas of different experimental groups of rats., Methods: We determinate the antioxidant activity by ABTS .+ and antioxidant total capacity (TAC) of all extracts of C. scolymus leaves, the inhibition of α-amylase activity in vitro was also investigated. Forty male Wistar rats were induced to diabetes with a single dose intraperitoneal injection (i.p.) of alloxan (150 mg/kg body weight (b.w.)). Diabetic rats were orally and daily administrated of ethanol extract from C. scolymus at two doses (200-400 mg/kg, b.w) or (12 mg/kg, b.w) with anti-diabetic reference drug, Acarbose for one month. Ethanol extract of C. scolymus effect was confirmed by biochemical analysis, antioxidant activity and histological study., Results: The results indicated that the ethanol extract from leaves of C. scolymus showed the highest antioxidant activity by ABTS .+ (499.43g± 39.72 Trolox/g dry extract) and (128.75 ± 8.45 mg VC /g dry extract) for TAC and endowed the powerful inhibition in vitro of α-amylase activity with IC50=72,22 ug/uL. In vivo, the results showed that ethanol extract from the leaves of C. scolymus (200-400 mg/kg) decreased significantly (p < 0.001) the α-amylase levels in serum of diabetic rats, respectively associated with significant reduction (p < 0.001) in blood glucose rate of 42,84% and 37,91% compared to diabetic groups after 28 days of treatment, a significant lowered of plasma total cholesterol (T-Ch) by 18,11% and triglyceride (TG) by 60,47%, significantly and low-density lipoproteins (LDL-C) by 37,77%, compared to diabetic rats, moreover, the administration of ethanol extract appears to exert anti-oxidative activity demonstrated by the increase of CAT, SOD and GSH activities in liver, kidney and pancreas of diabetic rats. This positive effect of the ethanol extract from C. scolymus was confirmed by histological study., Conclusion: These observed strongly suggest that ethanol extract from the leaves of C. scolymus has anti-hyperglycemic properties, at least partly mediated by antioxidant and hypolipidemic effects.

Two fern species Asplenium adiantum-nigrum L. and Asplenium trichomanes L. collected from the Kroumiria region (Northwest of Tunisia) were individually submitted to hydrodistillation in a Clevenger type apparatus. Volatile organic compounds were identified by GC-MS and GC-FID. Thus, 35 compounds were identified in A. adiantum-nigrum essential oil accounting for 77.5% of the whole constituents dominated by palmitic acid (34.5%); however, only 29 volatiles were identified in A. trichomanes showing a high amount of phytol, an odorous diterpene alcohol, representing 14.4% of the total oil contents. The total phenolic content and the antioxidant effects of crude extracts from both pteridophytes were determined using Folin-Ciocalteu and 2,2'-diphenyl-1-picrylhydrazyl free radical-scavenging assays, respectively. A. adiantum-nigrum ethyl acetate extract is shown to be lower in total phenolic contents (49.3 mg gallic acid equivalent/g) than similar extract from A. trichomanes (55.4 mg GAE/g)., (© The Author 2016. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.)

In the present investigation, extracts obtained from L. guyonianum Durieu ex Boiss. aerial parts were used to evaluate total phenolic, flavonoid and tannin contents. A study of antioxidant activities of the prepared samples was carried out on the basis of 1,1-Diphenyl-2-picrylhydrazyl (DPPH), 2-2'-azino-bis-(3-ethylbenz-thiazoline-6-sulfonic acid) (ABTS+.) and ferric reducing antioxidant power (FRAP) assays. Moreover, the efficiency of methanolic, chloroformic and petroleum ether extracts and the deriving fractions from the methanolic extract was tested against human bacterial and fungal pathogenic strains using micro dilution method in 96 multiwell microtiter plate. Furthermore, leaves and stems extracts were subjected to RP-HPLC for phenolic compounds identification. Results showed that polyphenolic contents and antioxidant activities varied considerably as function of solvent polarity. Moreover, antiradical capacities against DPPH, ABTS(+.) and reducing power were maxima in methanol aerial parts extract which showed the highest polyphenol contents (134mg CE/g DW). The antimicrobial activities showed that methanolic, chloroformic and petroleum ether extracts were found to be most potent against Pseudomonas aeruginosa and Staphylococcus aureus with MIC values of 23 and 46μ.mL(-1), respectively. The fractions F(13) and F(16) have a great antifungal potential against Candida glabrata, Candida krusei and Candida parapsilesis (MIC=39μ.mL(-1)). The RP-HPLC analysis lead the identification of gallic, procatechuic and trans-cinnamic acids, methyl-4-hydroxybenzoate, n-propyl-3,4,5-trihydroxybenzoate, epicatechin, naringin and myricetin in L. guyonianum Durieu ex Boiss. leaves and stems extracts.

Artichoke (Cynara scolymus) leaf extract was one of the few herbal remedies which the clinical and experimental trials have complemented each other. Both experimental and clinical effects have been verified through extensive biomedical herbal remedy research. Specifically, antioxidant, choleretic, hepatoprotective, bile-enhancing and lipid-lowering effects have been demonstrated, which corresponded with its historical use. Ongoing research seems to indicate that artichoke indeed have medicinal qualities. Most significant appears to be its beneficial effect on the liver. In animal studies, liquid extracts of the roots and leaves of artichoke have demonstrated an ability to protect the liver, with possibly even to help liver cells regenerate. Although research is not yet conclusive, scientists were optimistic that its long-standing use in humans for digestive and bowel problems was indeed justified. It may also play a role in lowering cholesterol and thus help to prevent heart disease. Boiled wild artichoke reduced postprandial glycemic and insulinemic responses in normal subjects but has no effect on metabolic syndrome patients. This article intended to review the wide ranging pharmacological effects of artichoke leaf extract.

Phytochemical investigation of chloroform extract from the leaves of the marine plant Posidonia oceanica (L.) Delile (Posidoniaceae), yielded posidozinol, a new methylated sesquiterpene along with β-sitosterol and four known fatty acids: palmitic, palmitoleic, oleic and linoleic acids. The structure elucidation has been established on the basis of 1D- and 2D-NMR spectroscopy, GS/MS and ES mass spectrometry. Antibacterial effects of crude extracts from P. oceanica were evaluated against: Pseudomonas aeruginosa, Escherichia coli, Staphylococcus aureus, Staphylococcus epidermidis and Micrococcus luteus microorganisms.

Bioactivity guided fractionation of Echiochilon fruticosum Desf. (Boraginaceae) butanolic extract biautography assay against fungi led to the isolation of a new bioactive alkaloid, named saoussanabiloïde (1). Its structure was established on the basis of spectroscopic measurements, IR, MS and 2D NMR using COSY, HMQC and HMBC experiments. The strongest inhibitory effect of the butanolic extract, from fractions derived from the crude extract and saoussanabiloïde (1), were observed against Fusarium oxysporum f. sp. niveum.

Repeated fractionation of the acetylated methanol extract of Prasium majus afforded acetylated derivatives of a new iridoid glycoside hamighriprasin (1), myoporoside (2), beta-D-glycopyranose (3) and saccharose (4). The structures of 1 and 2 were established by interpretation of 1D and 2D NMR data of their corresponding acetylated derivatives and by comparison with the literature.

The aerial parts of the Tunisian plant Echiochilon fruticosum yielded a novel flavonol diglycoside: naringenin-5-O-beta-D-glycopyranoside-3-O-alpha-L-rhamnopyranoside, named Echiofruzine (1), together with the known compounds vomifoliol-9-O-beta-D-glucopyraroside (2), 1-oxo-alpha-ionyl-9-O-beta-D-glucopyranoside (3) and 1-O-[beta-D-xylopyranosyl(1 --> 6)-beta-D-glucopyranosyl] eugenol (4), described for the first time in the indicated plant. The structures of the four isolated compounds were established on the basis of chemical and spectroscopic evidence.