Search results for "DPP"
showing 10 items of 168 documents
Phytochemical Profile and Antioxidant Activity of the Aerial Part Extracts from Matthiola incana subsp. rupestris and subsp . pulchella ( Brassicacea…
2021
As part of a project aimed at investigating the Matthiola taxa endemic to Sicily (Italy), this study focused on Matthiola incana, an edible species used in the traditional medicine of various countries. Herein, the characterization of phenolic and volatile compounds, the antioxidant capacity in vitro (1,1-diphenyl-2-picrylhydrazil (DPPH), reducing power and Fe2+ chelating activity assays) and the toxicity test (Artemia salina lethality bioassay) of the hydroalcoholic extracts from the aerial parts of M. incana subsp. rupestris from Mt. Pellegrino (Palermo) and Mt. Erice (Trapani), and of M. incana subsp. pulchella are reported. The results are compared with those previously shown for M. inc…
Free radical scavenging capability, antioxidant activity and chemical constituents of Pyrola incarnata Fisch. leaves
2013
Abstract In the present study, the crude extract and its four fractions of petroleum ether, ethyl acetate, n-butanol, water from Pyrola incarnata Fisch. leaves were prepared and their antioxidant activities were investigated by using four antioxidant assays in vitro. The ethyl acetate fraction showed remarkably strong antioxidant activities on 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging, ABTS radical scavenging, reducing power and β-carotene-linoleic acid bleaching, which were almost comparable to capacities of the positive controls (VC and BHT). The ethyl acetate fraction had the highest total phenolic and total flavonoid contents. Furthermore, Pearson correlation analysis was …
Enzyme pretreatment and negative pressure cavitation extraction of genistein and apigenin from the roots of pigeon pea [Cajanus cajan (L.) Millsp.] a…
2012
Abstract An enzyme pretreatment and negative-pressure cavitation extraction (E-NPCE) method was investigated for extraction genistein and apigenin from pigeon pea roots. The important parameters involved in E-NPCE process were optimized by single-factor experiments and then critical parameters were investigated by a 2 3 full factorial central composite design (CCD) to optimize extract conditions. Under optimal conditions, the yields of genistein and apigenin were 0.628 mg/g and 0.359 mg/g, which represented an increase of 44.70% and 53.05%, respectively, compared to standard NPCE. Furthermore, from DPPH scavenging activity test the extract of E-NPCE showed better antioxidant activity than t…
Antioxidant properties, superoxide dismutase and glutathione reductase activities in HepG2 cells with a fungal endophyte producing apigenin from pige…
2012
Abstract A fungal endophyte MD89 with obvious antioxidant activities was isolated from pigeon pea and identified as Chaetomium globosum by ITS sequence. Different fractions from MD89 culture were compared and evaluated by total phenol (TP) content, total flavonoid (TFL) content, DPPH radical scavenging, reducing power and lipid peroxidation assays, respectively. Results showed that EtOAc extracts had high content of TP and TFL, and strong antioxidant activities (IC 50 value was 6.87, 15.19, 16.78 μg/mL, respectively). Furthermore, the EtOAc extracts were analyzed by LC–MS/MS and a good antioxidant compound, apigenin, was found. The activities of superoxide dismutase (SOD) and glutathione re…
Effects of ultrasound-assisted extraction on physicochemical properties, bioactive compounds, and antioxidant capacity for the valorization of hybrid…
2021
Samples of tree hybrid mandarins (´Clemenvilla`, ´Ortanique` and ´Nadorcott`) were employed to determine the physicochemical properties (increase of conductivity, brix° and pH), bioactive compounds (total phenolic, flavonoid, ascorbic acid and carotenoids content) and antioxidant capacity (DPPH and TEAC) of peels. Mandarin peel extracts were prepared employing ultrasound assisted extraction (400 W, 80% v/v duty cycle, 40ºC). The results were compared to the values of control extraction method. Aqueous ethanol solution (50%, v/v) was used as solvent in solid-liquid ratio of 1:10 (w/v). A 5, 15 and 30 min were applied in both methods to stablish the most effective extraction time. The increas…
Evaluating the potential of cell disruption technologies for green selective extraction of antioxidant compounds from Stevia rebaudiana Bertoni leaves
2015
Abstract An increased interest has been shown by both food technologists and food industry regarding Stevia rebaudiana Bertoni leaves ( Stevia ) for their high content of bioactive components (phenolic compounds, vitamin C, carotenoids). The aim of this work was to study the effect of emerging technologies such as high voltage electrical discharges (HVED) and pulsed electric fields (PEF) and ultrasounds (US) on the intensification of the extraction of valuable compounds from Stevia leaves. The proposed processes combined pretreatment (HVED, PEF and US) and extraction of intracellular compounds using water as solvent at ambient temperature. The energy inputs of the treatments varied from 24 …
Tomato peel drying and carotenoids stability of the extracts
2014
Summary Tomato peels were firstly dried by different methods (hot air, freeze-drying, and fluidized bed drying) to evaluate the recovery of lycopene, β-carotene and DPPH radical scavenging activity. Comparison of the results showed that hot air drying at 50 °C was a suitable method and alternative to freeze-drying to preserve carotenoids compounds and antioxidant activity in tomato peels. Then, ethanol/ethyl acetate (1:1) extracts from tomato peel, previously dried at 50 °C by hot air, were submitted to heat (100 °C) and light treatment (1000 lumen) to evaluate their stability as natural food dyes. Heating of the extracts caused a progressive reduction of total carotenoids, up to about 30% …
A new ceramide from the leaves of Lannea schimperi (Hochst. ex A.Rich.) Engl.
2020
A new ceramide is being reported herein together with six known compounds from the methanol extract of the leaves of Lannea schimperi (Hochst. ex A.Rich.) Engl. The metabolites were obtained through repeated open column chromatography and were characterized by spectroscopic and spectrometric techniques. The radical-scavenging activity of the crude extract and isolated compounds was evaluated using the DPPH radical. The obtained results suggest the studied species as prominent candidate to fight reactive oxygen species (ROS).
Complessi di Platinum(II): sintesi, studi di DNA-binding e loro attività antitumorale in vitro
2013
Con lo scopo di trovare nuovi analoghi del Cis-DDP (cis-diammino dicloro platino(II)) nuovi complessi del platino sono stati sintetizzati, caratterizzati e ne è stata studiata l’attività antitumorale in vitro [1]. Recentemente sono stati preparati complessi con metalli del quarto periodo di transizione con entrambi i leganti, dipirido[3,2-a:2’,3’-c]fenazina (dppz) e glicinato (gly) [2]. I composti di nuova sintesi vengono generalmente caratterizzati attraverso parecchie tecniche analitiche incluso la cristallografia a raggi-X e la loro attività antitumorale viene testata su un vasto pannello di linee cellulari umane [1,2]. Le proprietà biologiche spesso sono correlate alla loro interazione …
Glucose lowering and anti-atherogenic effects of incretin-based therapies: GLP-1 analogues and DPP-4-inhibitors
2009
Type 2 diabetes is a chronic, progressive disease with a multi-faceted pathophysiology. Beyond the known defects of insulin resistance and beta-cell insufficiency, derangement of incretin hormones normally produced from the gut wall in response to food intake play an important role. In recent years, the 'incretin-based' therapies (IBTs) have been developed to address hyperglycemia through either mimicking the action of the endogenous incretin glucagon-like polypeptide (GLP-1) (GLP-1 receptor agonists) or by inhibiting the activity of the enzyme that degrades GLP-1 (the dipeptyl peptidase-4 inhibitors).We reviewed available evidence on the glucose lowering and anti-atherogenic effects of IBT…