Citrus medica L. cv Diamante (Rutaceae) peel extract improves glycaemic status of Zucker diabetic fatty (ZDF) rats and protects against oxidative stress.

This study aimed to investigate the antidiabetic, antilipidaemic and antioxidant activities of Citrus medica cv Diamante (Rutaceae) hydroalcoholic (CD) peel extract in Zucker diabetic fatty (ZDF) rats. The ability of CD to protect against oxidative stress was investigated by using different in vitro assays and in vivo by using the reactive oxygen metabolites-derived compounds (d-ROMs) test and the biological antioxidant potential test (BAP). Two different doses of CD extract (300 and 600 mg/kg/die) were administered at ZDF rats for 4 weeks. CD reduced cholesterol and triglycerides levels. A dose-dependent effect on body weight and serum glucose levels was observed. A decrease of d-ROMs and an increase of BAP were recorded by using the dose of 600 mg/kg. The extract inhibited lipid peroxidation (IC50 value of 0.23 mg/ml). These findings suggest as an efficient phytotherapeutic approach in combating hyperlipidaemic and hyperglycaemic disorders.

Crocus cancellatus subsp. damascenus stigmas: chemical profile, and inhibition of α-amylase, α-glucosidase and lipase, key enzymes related to type 2 diabetes and obesity.

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.

Inhibitory Effect on Lipid Absorption and Variability of Chemical Constituents from Capparis sicula subsp. sicula and Capparis orientalis.

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.

Chemical Profile and Antioxidant Properties of Extracts and Essential Oils from Citrus × limon (L.) Burm. cv. Femminello Comune.

Citrus × limon cv. Femminello Comune (Rutaceae) from Rocca Imperiale (Italy), one of the six Protected Geographical Indication (PGI) Italian lemon crops, has been recently received renewed interest. In this work, fresh and dried peels and leaves were extracted by hydrodistillation, supercritical fluid extraction (SFE), and Soxhlet apparatus. Chemical profile was assessed by gas chromatography (GC) and gas chromatography/mass spectrometry (GC/MS). Except for leaves extracts obtained by Soxhlet apparatus, the monoterpene hydrocarbons fraction dominated. Limonene, γ-terpinene, and ß-pinene were the main identified compounds. The antioxidant activity was investigated using different in vitro assays namely 2,2-diphenyl-1-picrylhydrazyl (DPPH), ABTS, ferric reducing ability power (FRAP), and ß-carotene bleaching test. In DPPH test, the essential oil obtained by hydrodistillation of fresh peel exhibited the highest activity (IC50 of 1.17 mg/ml). Leaves extracted by SFE showed a good activity in both DPPH and ß-carotene bleaching test with IC50 values of 2.20 and 6.66 mg/ml, respectively. Monoterpene hydrocarbons fraction exhibited a positive Pearson's correlation coefficient with all antioxidant assays. Leaves, often considered waste material, should be considered from a different point because they represent a matrix of indisputable interest.

Hypolipidemic and Antioxidant Properties of Hot Pepper Flower (Capsicum annuum L.).

At present, the various medical treatments of obesity involve side effects. The aim of the research is therefore to find natural compounds that have anti-obesity activity with minimum disadvantages. In this study, the hypolipidemic effect of hydroalcoholic extract of flowers from Capsicum annuum L. was examined through the evaluation of inhibition of pancreatic lipase. Antioxidant activity was assessed using different tests: 2,2-diphenyl-1-picrylhydrazyl (DPPH), nitric oxide (˙NO) and lipid peroxidation inhibition assays. Phytochemical analysis indicated that total phenolic and flavonoid content in the extract was 128.7 ± 4.5 mg chlorogenic acid equivalent/g of crude extract and 17.66 ± 0.11 mg of quercetin equivalent/g of crude extract, respectively. The extract inhibited pancreatic lipase with IC50 value equal to 3.54 ± 0.18 mg/ml. It also inhibited lipid peroxidation with IC50 value of 27.61 ± 2.25 µg/ml after 30 min of incubation and 41.69 ± 1.13 µg/ml after 60 min of incubation. The IC50 value of radical scavenging activity was 51.90 ± 2.03 µg/ml. The extract was also able to inhibit NO production (IC50 = of 264.3 ± 7.98 µg/ml) without showing any cytotoxic effect.

Antioxidant and Carbohydrate-Hydrolysing Enzymes Potential of Sechium edule (Jacq.) Swartz (Cucurbitaceae) Peel, Leaves and Pulp Fresh and Processed.

Sechum edule peel, leaves and pulp were investigated for their chemical composition (total phenol, flavonoid, carotenoid and vitamin C content), and for antioxidant activity and carbohydrate-hydrolysing enzymes (α-amylase and α-glucosidase) inhibition. In order to evaluate the incidence of cooking process on retention of healthy phytochemicals, the pulp was subjected to different treatments (grill roasting, domestic oven baking, microwave cooking, blanching and steaming). Cooking processes reduced the total phenol content (58.5 mg/g extract for fresh pulp vs 26.3 and 29.3 mg/g extract for roasted and steamed samples, respectively). Pulp was found to be the most active in 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid) (ABTS) (IC50 of 0.1 mg/mL), whereas peel showed the highest activity in 2,2-diphenyl-1-picrylhydrazyl (DPPH) test (IC50 of 0.4 mg/mL). Moreover, peel exhibited the highest inhibitory activity against α-amylase with an IC50 of 0.2 mg/mL, except for steamed cooking process, which drastically influenced the bioactivity against both enzymes.

Antibacterial, antioxidant and hypoglycaemic effects of Thymus capitatus (L.) Hoffmanns. et Link leaves' fractions.

The aim of this study was to examine the bioactivity of the methanol fraction (MF) and n-hexane fraction (HF) of Thymus capitatus leaves in relation to their constituents analysed by gas chromatography and gas chromatography-mass spectrometry. The effects of T. capitatus on the growth of pathogenic bacteria associated with respiratory diseases (13 gram-positive and 4 gram-negative) were determined using a microdilution method. The MF was particularly effective on Streptococcus pneumoniae and Moraxella catarrhalis. The antioxidant activity was evaluated by 2,2-diphenyl-1-picrylhydrazyl, 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid), ferric-reducing antioxidant power and ß-carotene bleaching assays. A strong activity using ß-carotene bleaching test was observed with the MF (IC50 of 0.7 µg/mL after 30 min of incubation). In the hypoglycaemic test, a selective α-amylase inhibitory activity was detected with the HF begging the most active (IC50 of 422.5 µg/mL). T. capitatus may represent a source of natural bioactive compounds.

Anti-rancidity effect of essential oils, application in the lipid stability of cooked turkey meat patties and potential implications for health.

Twenty-three commercial essential oils were tested for their anti-rancidity effect and potential implications to prolong the induction time of corn oil and extend the shelf life of cooked turkey patties. Moreover, the potential health benefit was investigated through DPPH, ABTS, ß-carotene bleaching, FRAP, and α-amylase inhibitory assays. Essential oils' composition was investigated by GC-MS. Cumin, thyme, clove, and cinnamon oils improved oxidative stability and increased the induction time of the corn oil 1.5-3 fold. Clove and cinnamon oils were particularly effective in delaying lipid oxidation of cooked turkey patties (time of induction 11.04 and 9.43 h) compared with the plain burger (5.04 h). Both oils are also characterized by a potent radical scavenging activity in ABTS test (IC(50) values of 1.43 and 2.05 µg/ml for cinnamon and clove, respectively). In the α-amylase inhibitory assay, cumin and grape fruits were the most potent with IC(50) values of 21.88 and 23.95 µg/ml, respectively.

Prunus persica var. platycarpa (Tabacchiera Peach): Bioactive Compounds and Antioxidant Activity of Pulp, Peel and Seed Ethanolic Extracts.

A comparative analysis of ethanol extracts from peel, pulp and seed of Prunus persica var. platycarpa (Tabacchiera peach) was done. The total phenol, flavonoid and carotenoid content as well as the antioxidant properties by using different in vitro assays (DPPH, ABTS, FRAP, Fe-chelating, ß-carotene bleaching test) were evaluated. Pulp extract was subjected to liquid chromatography-electrospray-tandem mass spectrometry (HPLC-ESI-MS/MS). Gallic acid, protocatechuic acid, protocatechualdehyde, chlorogenic acid, p-coumaric acid, and ferulic acid were identified as main constituents. Pulp extract was characterized by the highest total phytonutrients content and exhibited the highest antioxidant activity in all in vitro assays (IC(50) values of 2.2 µg/mL after 60 min of incubation by using ß-carotene bleaching test and 2.9 µg/mL by using Fe-chelating assay). Overall, the obtained results suggest that P. persica var. platycarpa displays a good antioxidant activity and its consumption could be promoted.

An overview on chemical aspects and potential health benefits of limonoids and their derivatives.

Limonoids are heavily oxygenated, modified triterpenes dominant in Meliaceae and Rutaceae plant families. The term 'limonoid' is derived from limonin, which was first identified as the bitter constituent of Citrus seeds in 1841. This group of secondary metabolites exhibits a wide range of biological properties, including anticancer, antibacterial, antifungal, antimalarial, and antiviral activities. Significant progress on the role of limonoids as promising candidates for cancer chemoprevention and/or therapy has been achieved in particular in recent years. The aim of this review article is to discuss the recent developments on limonoids chemical aspects and biological activities with the relationship between structure and activity, supporting the new possibilities for the medicinal and/or nutraceutical use of these compounds.

In vitro investigation of the bioaccessibility of carotenoids from raw, frozen and boiled red chili peppers (Capsicum annuum).

BACKGROUND: Carotenoid-rich foods are associated with antioxidant activity and the ability to alleviate chronic diseases. PURPOSE: The present study investigated the effect of processing on the content and bioaccessibility of carotenoids from 13 cultivars of red chili pepper (Capsicum annuum). METHODS: Carotenoids in chili peppers were analyzed before an in vitro digestion process. The portion of carotenoid transferred to the micelle fraction (bioaccessibility) was also quantified. RESULTS: ß-Carotene, ß-cryptoxanthin, capsanthin and antheraxanthin were the most abundant carotenoids. Zeaxanthin, violaxanthin, neoxanthin and lutein were detected at lower concentrations. In general, freezing and boiling reduced carotenoid contents. Capsanthin and zeaxanthin had the highest bioaccessibility at an average value from 36 to 40%, followed by antheraxanthin (26%). Bioaccessibility of ß-cryptoxanthin, violaxanthin and ß-carotene was lower, averaging 6.1, 4.8 and 4.0%, respectively. Neoxanthin and lutein were not detected in micelles. Freezing increased the bioaccessibility of capsanthin, zeaxanthin, antheraxanthin, ß-cryptoxanthin and violaxanthin; ß-cryptoxanthin bioaccessibility increased and capsanthin and zeaxanthin bioaccessibility decreased following boiling. CONCLUSIONS: Differences in the contents and bioaccessibility of carotenoids in 13 C. annuum cultivars and between the processed methods were herein evidenced.

Chemical profiling and in vitro biological effects of Cardiospermum halicacabum L. (Sapindaceae) aerial parts and seeds for applications in neurodegenerative disorders.

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.

In vitro investigation of the potential health benefits of wild Mediterranean dietary plants as anti-obesity agents with α-amylase and pancreatic lipase inhibitory activities.

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.

Chemical composition and bioactivity of dried fruits and honey of Ficus carica cultivars Dottato, San Francesco and Citrullara.

BACKGROUND: The aim of this study is to evaluate, for the first time, the chemical profile, antioxidant properties and cholinesterase inhibitory activity of dried fruits and honey of Ficus carica (fig) cultivars Dottato, Citrullara, and San Francesco. RESULTS: Gas chromatography-mass spectrometry (GC-MS) analysis of fig extracts identified terpenes, sterols and fatty acids as major constituents. The aroma profile of honey obtained from a mixture of the three cultivars was investigated by solid-phase micro-extraction/GC-MS. 5-(Hydroxymethyl)-2-furancarboxaldehyde, 2,3-dihydro-3,5-dihydroxy-6-methyl-4H-pyran-4-one and 1,3-dihydroxy-2-propanone were the main compounds. Total phenol, flavonoid and anthocyanin content are also reported. The San Francesco cultivar is characterised by the highest phenol and flavonoid content, while Dottato showed the major anthocyanin content. The Dottato cultivar exhibited the best radical scavenging activity against both 2,2'-azinobis-(3-ethylbenzothiazoline-6-sulfonic acid) and 2,2-diphenyl-1-picrylhydrazyl radicals (IC50 values of 5.4 and 22.6 µg mL(-1) , respectively). This cultivar also showed the highest inhibitory activity against both acetylcholinesterase and butyrylcholinesterase, with IC50 values of 26.9 and 31.8 µg mL(-1) , respectively. CONCLUSION: Dried figs are a convenient source of bioactive compounds that demonstrated potential neuroprotection and antioxidant effects. Therefore, the addition of figs to the human diet should be recommended by dieticians and nutritionists.

Hypericum perforatum: Influences of the habitat on chemical composition, photo-induced cytotoxicity, and antiradical activity.

CONTEXT: Hypericin, isolated from Hypericum perforatum L. and about another 300 Hypericum species (Guttiferae), is one of the most powerful photosensitizers found in nature. OBJECTIVE: The aim of this study was to assess the variability of chemical composition and biological activities of four H. perforatum samples, collected at different altitudes in the South Apennine of Italy. MATERIALS AND METHODS: MTT assay was used to evaluate the antiproliferative activity of different samples concentrations (0.6-100 µg/mL) after irradiation at 365 nm. The inhibition of nitric oxide production was evaluated after 24 h of incubation using the macrophage cell line RAW 264.7 and sample solutions ranging from 12.5 to 1000 µg/mL. Antioxidant activities were evaluated using 2,2-diphenyl-1-picrylhydrazyl (DPPH) assay and ß-carotene bleaching test (ranges were 12.5-1000 and 1-400 µg/mL, respectively). Chemical composition was evaluated through HPTLC, and different contents of hypericin and rutin have been observed. RESULTS: The most phototoxic sample was collected from Zumpano (no. 1 at 370 m), with IC50 values of 24.61 ± 0.02 µg/mL. Sample no. 1 showed also the best radical scavenging activity (IC50 value of 9.18 ± 0.03 µg/mL) and the best antioxidant activity (IC50 value of 10.04 ± 0.03 µg/mL after 30 min of incubation). Best activity of extract no. 1 was well in accordance with chemical data, including the phenolic total content and particular metabolome profile. DISCUSSION AND CONCLUSION: This paper confirms the usefulness in maintaining the exploration of H. perforatum activities, in order to confirm its potentiality as a multipurpose plant.

In vitro assessment of the bioaccessibility of carotenoids from sun-dried chilli peppers.

Chilli peppers have been recognized as an excellent source of antioxidants as they are rich in bioactive phytochemicals such as carotenoids which are known to exert various beneficial effects in vivo. Absorption is an important factor in the determination of the potential biological effects of carotenoids. The bioaccessibility of a food constituent such as a carotenoid represents its potential to be absorbed in humans. There is very limited information in the literature regarding the content and bioaccessibility of carotenoids from dried peppers. Therefore, the objectives of the present study were: first, to determine the carotenoid content of 20 varieties of red, orange or yellow coloured sun-dried chilli peppers belonging to either of four Capsicum species (annuum, baccatum, chinense and chacoense); and second, to quantify the carotenoid micellarization (bioaccessibility) following an in vitro digestion procedure. Red peppers had a higher carotenoid content and bioaccessibility than either the orange peppers or yellow pepper. Xanthophylls showed greater bioaccessibility than carotenes. Our findings confirm that dried chilli peppers are a good source of carotenoids.

Conjugation of l-NAME to prenyloxycinnamic acids improves its inhibitory effects on nitric oxide production.

A series of 10 compounds resulting from the conjugation of O-prenylated naturally occurring benzoic and cinnamic acids to l-NAME were synthesized and tested together with the corresponding unprenylated parent molecule as anti-inflammatory agents for their inhibitory effects on NO production in LPS-stimulated RAW 264.7 macrophages. Results indicated that the coupling between O-geranyl and O-isopentenylcinnamic acids and l-NAME led to products with an enhanced activity when compared to the parent compounds.

Angiotensin-converting enzyme inhibitory activity and antioxidant properties of Nepeta crassifolia Boiss & Buhse and Nepeta binaludensis Jamzad.

This article reports phytochemical and biological studies on Nepeta binaludensis and Nepeta crassifolia. Both species were investigated for their angiotensin-converting enzyme (ACE) inhibitory activity and antioxidant properties through three in vitro models [2,2-diphenyl-1-picrylhydrazyl (DPPH), 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid) (ABTS) and ferric reducing antioxidant power (FRAP) assay]. Aerial parts were extracted with methanol and partitioned between water and subsequently n-hexane, ethyl acetate and n-butanol. N. binaludensis methanol extract exerted significantly higher reducing power (1.9 µM Fe(II)/g) than did the positive control butylhydroxytoluene (63.2 µM Fe(II)/g) in FRAP assay. The highest DPPH radical scavenging activity was found for N. crassifolia, with IC50 values of 9.6 and 12.1 µg/mL for ethyl acetate and n-butanol fractions, respectively. n-Butanol fraction of both species showed the highest ACE inhibitory activity, with IC50 values of 59.3 and 81.7 µg/mL for N. binaludensis and N. crassifolia, respectively. Phytochemical investigations resulted in the isolation of ursolic acid, oleanolic acid, apigenin, luteolin and ixoroside. Apigenin-7-O-glucoside, 8-hydroxycirsimaritin and cirsimaritin were furthermore identified in N. crassifolia ethyl acetate-soluble fraction. Nepetanudoside B was isolated from the n-butanol fraction of N. binaludensis.

Oldenlandia diffusa extracts exert antiproliferative and apoptotic effects on human breast cancer cells through ERα/Sp1-mediated p53 activation.

Breast cancer is the most frequent tumor and a major cause of death among women. Estrogens play a crucial role in breast tumor growth, which is the rationale for the use of hormonal antiestrogen therapies. Unfortunately, not all therapeutic modalities are efficacious and it is imperative to develop new effective antitumoral drugs. Oldenlandia diffusa (OD) is a well-known medicinal plant used to prevent and treat many disorders, especially cancers. The aim of this study was to investigate the effects of OD extracts on breast cancer cell proliferation. We observed that OD extracts strongly inhibited anchorage-dependent and -independent cell growth and induced apoptosis in estrogen receptor alpha (ERα)-positive breast cancer cells, whereas proliferation and apoptotic responses of MCF-10A normal breast epithelial cells were unaffected. Mechanistically, OD extracts enhance the tumor suppressor p53 expression as a result of an increased binding of ERα/Sp1 complex to the p53 promoter region. Finally, we isolated ursolic and oleanolic acids as the bioactive compounds able to upregulate p53 expression and inhibit breast cancer cell growth. These acids were greatly effective in reducing tamoxifen-resistant growth of a derivative MCF-7 breast cancer cell line resistant to the antiestrogen treatment. Our results evidence how OD, and its bioactive compounds, exert antiproliferative and apoptotic effects selectively in ERα-positive breast cancer cells, highlighting the potential use of these herbal extracts as breast cancer preventive and/or therapeutic agents.

Wild Mediterranean dietary plants as inhibitors of pancreatic lipase.

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.