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In continuation of our research program on Mediterranean dietary plants, a bioassay-guided fractionation of extracts from several accessions of Capparis sicula subsp. sicula and Capparis orientalis aerial parts was carried out. Antilipidemic activity of samples was assayed using inhibition of pancreatic lipase. To study the metabolic variability in Capparis species, HPTLC analyses were performed in order to characterize the species through the detection, isolation, and quantitative evaluation of rutin taken as significant chemical marker. The best activity was exerted by C. orientalis accession no. C10 and C. sicula subsp. sicula accession no. C6. The bioactivity evaluation of specific chemical markers, rutin and glucocapparin, led to the identification of a potent antilipidemic compound rutin. The HPTLC analysis showed large variation among the different analyzed samples with respect to rutin concentration. The chemical investigation showed a different composition between the species and between the collection zones. The variations showed by the studied accessions of caper could be attributed to exogenous factors. Capparis species contained predominantly quercetin rutinoside (rutin), accompanied by other constituents such as the glucosinolate glucocapparin. These rutin-rich extracts exhibited pronounced dose-dependent enzyme inhibitory activities toward pancreatic lipase., (© 2016 Verlag Helvetica Chimica Acta AG, Zürich.)

Spices are appreciated for their medicinal properties besides their use as food adjuncts to enhance the sensory quality of food. In this study, Crocus cancellatus subsp. damascenus was investigated for its antioxidant activities employing different in vitro systems. Stigma extract demonstrated a radical scavenging activity against both 2,2-diphenyl-1-picrylhydrazyl (DPPH) and 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid) (ABTS) radicals with IC50 values of 34.6 and 21.6 µg/mL and a good ferric reducing ability (53.9 µM Fe(II)/g). In order to clarify the potential functional properties of this spice, the carbohydrate-hydrolysing enzymes and pancreatic lipase inhibitory properties were investigated. Crocus cancellatus subsp. damascenus extract inhibited α-amylase and α-glucosidase with IC50 values of 57.1 and 68.6 µg/mL, respectively. The bioactivity was discussed in terms of phytochemicals content. The obtained results may be of interest from a functional point of view or as food additive and to promote the revalorization of this species.

Cardiospermum halicacabum is widely used in traditional medicine. Previous studies have focused on the aerial parts, while the seeds have been poorly investigated. This work aimed to analyse the chemical composition of extracts from aerial parts and seeds obtained using Naviglio and Soxhlet (PN, PS, and SN, SS, respectively), the inhibitory properties against tyrosinase, acetylcholinesterase (AChE), and butyrylcholinesterase (BChE) and the antioxidant effects. PN total extract showed significant anti-tyrosinase activity (IC50 value of 10.8 µg/mL). After partitioning with n-hexane, an HPLC method for analysing chemical constituents was established. Apigenin, luteolin, and apigenin-7-O-glucoside are the predominant constituents. SN n-hexane fraction was the most active inhibitor of BChE (IC50 of 57.9 µg/mL). Gas chromatography-mass spectrometry analysis revealed fatty acids, including eicosanoic acid, methyl 11-eicosenoate and oleic acid, as the major constituents. These findings suggest the potentiality of both seeds and aerial parts of C. halicacabum in the treatment of neurological disorders.

Background: Inhibition of digestive enzymes is one of the most widely studied mechanisms used to determine the potential efficacy of natural products as anti-obesity agents. In vitro studies reported here were performed to evaluate the inhibitory activity of formulations of edible plants from Italy on amylase and lipase by monitoring the hydrolysis of nitrophenyl caprilate and the hydrolysis of glycoside bonds in digestible carbohydrate foods., Results: The formulation obtained from Capparis sicula exhibited the strongest inhibitory effect on pancreatic lipase (IC50 = 0.53 mg mL(-1) ) while the Borago officinalis formulation exhibited the strongest inhibitory effect on α-amylase (IC50 = 31.61 µg mL(-1) ). In order to characterise the extracts, high-performance thin-layer chromatography analysis of the formulations was performed, revealing the predominance of (±)-catechin in Mentha aquatica formulation, rutin in C. sicula, and caffeic acid and chlorogenic acid in Echium vulgare., Conclusion: The results obtained indicated that the extracts of C. sicula and B. officinalis could be good candidates for further studies to isolate pancreatic lipase and α-amylase inhibitors, respectively., (© 2013 Society of Chemical Industry.)

Lipids are essential compounds for all living organisms. Agents that inhibit fat digestion are of theoretical benefit in the treatment of obesity. A total of 18 species (21 hydroalcoholic extracts) of edible plants from Calabria region (Italy) were evaluated for their in vitro pancreatic lipase inhibitory activity. Lipase activity was measured by monitoring the hydrolysis of p-NPC, which releases the yellow chromogen, p-nitrophenol. The aqueous ethanol extracts of Portulaca oleracea (leaves) and Silene vulgaris (leaves) exhibited the strongest inhibitory effect on lipase. The amounts of total phenolics, measured by Folin-Ciocalteu method, varied widely in the different analysed extracts and ranged from 29 to 482 mg/g of extract. In this study, the findings do not show any relationship between lipase inhibitory activity and total phenolic content., (Copyright © 2011 John Wiley & Sons, Ltd.)

Fruits of Ficus carica cultivar Dottato from Italy were examined to assess how the stage of ripeness influences their chemical composition, antioxidant activity, pancreatic lipase inhibition and antiproliferative properties on C32 melanoma cells. Fruits of the first harvest (June) showed a major content in furanocoumarins and pyranocoumarins whereas the fruits collected in September showed the highest polyphenolic content (11.9 mg/g of dried material). The total 70% ethanol extracts were portioned between methanol/water and n-hexane, dichloromethane and ethyl acetate, successively. Coumarins and fatty acid esters were the most abundant components of the n-hexane fractions. The dichloromethane fractions showed as major components 2 furanocoumarins (rutarenin and pimpinellin). The total extracts of F. carica cv. Dottato exhibited a significant dose-dependent antiradical and inhibition of lipid peroxidation activity, particularly fruits of the first harvest (June) that showed the highest activity with IC50 of 1.64 mg/mL and 0.004 mg/mL, respectively. Among single fractions, the ethyl acetate fraction from the second harvest (July) showed the highest antiradical activity with an IC50 value of 0.05 mg/mL while the dichloromethane fraction showed the best inhibition of lipid peroxidation with an IC50 value of 0.02 mg/mL. Dichloromethane fractions showed the highest photodynamic cytotoxicity with an IC50<5 μg/mL., (Copyright © 2012 Elsevier Ltd. All rights reserved.)

This study showed for the first time the antioxidant and hypoglycaemic properties of the methanol, n-hexane and ethyl acetate extracts from Senecio stabianus Lacaita, a plant that belongs to the Asteraceae family. The antioxidant activities were carried out using two different in vitro assays, namely 2,2-diphenyl-1-picrylhydrazyl (DPPH) test and 2,2'-azinobis(3-ethylbenzthiazoline-6-sulphonate) (ABTS) test. The ethyl acetate extract showed the highest activity with inhibitory concentration 50% (IC(50)) values of 35.5 and 32.7 µg mL(-1) on DPPH test and ABTS test, respectively. This activity may be related to a good total phenol and flavonoid content. All extracts were also tested for their potential inhibitory activity of α-amylase and α-glucosidase digestive enzymes. The n-hexane extract exhibited the highest α-amylase inhibition with an IC(50) value of 0.21 mg mL(-1). Through bioassay-guided fractionation processes seven fractions (A-G) were obtained and tested. Based on the phytochemical analysis, the activity of n-hexane extract may be related to the presence of monoterpenes and sesquiterpenes.

The present study aimed to evaluate for the first time the phenols, flavonoids, carotenoids, capsaicin and dihydrocapsaicin content and the antioxidant and hypoglycemic properties of Capsicum annuum var. acuminatum small and C. annuum var. cerasiferum air-dried fruits. The ethanol extract of C. annuum var. acuminatum small, characterized by the major content of total poliphenols, flavonoids, carotenoids and capsaicinoids, showed the highest radical scavenging activity (IC(50) of 152.9 μg/ml). On the contrary, C. annuum var. cerasiferum showed a significant antioxidant activity evaluated by the β-carotene bleaching test (IC(50) of 3.1 μg/ml). The lipophilic fraction of both C. annuum var. acuminatum and C. annuum var. cerasiferum exhibited an interesting and selective inhibitory activity against α-amylase (IC(50) of 6.9 and 20.1 μg/ml, respectively).

The inhibition of alpha-glucosidase and alpha-amylase, enzymes involved in the digestion of carbohydrates, can significantly reduce the post-prandial increase of blood glucose and therefore can be an important strategy in the management of blood glucose level in type 2 diabetic and borderline patients. Currently, there is renewed interest in plant-based medicines and functional foods modulating physiological effects in the prevention and cure of diabetes and obesity. The plant kingdom is a wide field to search for natural effective oral hypoglycaemic agents that have slight or no side effects. More than ca. 1200 plant species have been recorded to be used empirically worldwide for their alleged hypoglycaemic activity. Therefore, natural alpha-glucosidase and alpha-amylase inhibitors from plant sources offer an attractive strategy for the control of hyperglycaemia. This article reviews recent data on plant extracts and isolated natural compounds that are being tested for their hypglycaemic activity, highlights ongoing research and considers the future persepctives.

The present study showed for the first time the biological properties of different fractions from Cardamine battagliae Cesca & Peruzzi, an apoendemic Calabrian (southern Italy) plant that belongs to the Cruciferae family. The antioxidant activities of the different fractions of C. battagliae were carried out using two different in vitro assays (beta-carotene bleaching test and lipid peroxidation of liposomes assay) while radical scavenging activity was carried out using DPPH test. AcOEt fraction showed the highest activity on DPPH inhibition (IC50 of 0.162 mg mL(-1)) while dichloromethane fraction showed the highest activity on beta-carotene bleaching (IC(50) of 0.004 mg mL(-1)). The assay for alpha-amylase inhibition showed that n-hexane fraction showed the highest activity with an IC50 of 0.055 mg mL(-1).

The inhibitory activity of alpha-amylase and the phytochemical composition of Cedrus libani essential oils obtained from wood, leaves and cones were investigated. The C. libani woods oil exhibit an IC(50) value of 0.14 mg/ml, whereas the leaves and cones oils were devoid of any significant activity.

Hypoglycaemic effects of Salsola kali, S. soda, and S. oppositifolia (Chenopodiaceae) aerial parts were examined using in vitro assay based on the inhibition of a-amylase. The S. kali ethyl acetate fraction was the most active with a C1050 value 0.022 mg/ml. Through bioassay-guided fractionation processes two flavonol glycosides, isorhamnetin-3-O-glucoside and isorhamnetin-3-O-rutinoside, were isolated by silica gel column chromatography and characterized by spectroscopic methods. Isorhamnetin-3-O-rutinoside showed an interesting activity (IC50 0.129 mM).

Licorice root contains chemically diverse compounds that exhibit estrogenic effects in vitro and in vivo. The chalcone isoliquiritigenin (ISL) is a component of licorice extract exhibiting either antitumorigenic activity or estrogen receptor (ER) alpha-dependent growth promoting effects on breast cancer cells. In order to contribute to a better understanding of this apparent paradox, we synthesized and ascertained the estrogenic properties of ISL using, as model systems, the hormone-sensitive MCF7 breast cancer cells and the steroid-independent HeLa cells. Transfection experiments reveal that ISL is able to transactivate the endogenous ER alpha in MCF7 cells and this is supported by the capability to induce down-regulation of ER alpha protein levels and up-regulation of pS2 mRNA. Moreover, by using chimeric proteins consisting of the hormone binding domains of ER alpha and ER beta fused to the Gal4 DNA binding domain, we have determined that ISL is an estrogenic agonist of both ER isoforms. As a biological counterpart, low and intermediate ISL concentrations that induce substantial transcriptional activity stimulate the proliferation of MCF7 cells. However, high levels of ISL become cytotoxic even in steroid-receptor negative HeLa cells. Thus, the activity of ISL and the balance between risk or chemopreventive factor for estrogen-dependent breast cancer may depend on dietary intake.