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Highlights • Quantitative determination of bioactive sinapine in rapeseed pomace (RSP) extract. • Anti-oxidant/radical scavenging properties of sinapine at RSP extract concentration. • DNA protective properties of sinapine against free radical inducer. • Sinapine inhibited AChE, a target for treatment of neurodegenerative diseases. • RSP is a source of bioactive compounds for nutraceutical & pharmaceutical industry. Abstract Sinapine is the main secondary metabolite present in rapeseed pomace (RSP) with its concentration being dependent on rapeseed processing, growing conditions, extraction parameters and the country of origin. Here we report, the concentration of sinapine from an extract of defatted RSP harvested in the North East of Scotland. Using liquid chromatography tandem mass spectrometry, the most abundant phenolic compound in the RSP extract was, as expected, sinapine (109.1 mg/g RSP extract). Additionally, sinapic, caffeic, ferulic and syringic acids were identified (0.159–3.91 mg/g RSP extract). Sinapine together with the phenolics at the concentration present in the RSP extract, exhibited ≥50% activity relative to the extract in antioxidant assays. Furthermore, sinapine provided plasmid DNA (pBR322) protection, from 2,2′-azobis(2-amidinopropane) dihydrochloride and inhibited acetylcholinesterase activity by 85%. Molecular docking was utilised to explain the inhibitory activity. RSP can be an excellent source of bioactive compounds for pharmaceuticals, food additive and nutraceutical applications. [ABSTRACT FROM AUTHOR]

Highlights • The scavenging activity of DPPH and ABTS increased proportionally. • Linear regression and direct interpolation were not appropriate methods. • The correlation of the grape skin extract demonstrated the positive relationship. Abstract The antioxidant capacities of Kyoho skin, seed, and flesh extracts were determined using DPPH and ABTS assays and a suitable statistical program was tested for the prediction of EC 50 values of Kyoho skin, seed, and flesh extracts obtained by DPPH and ABTS assays. Statistical programs: OriginPro® version 8, GraphPad Prism® version 7, GraphPad Prism® version 7 five-parameter (5P) logistic model, SigmaPlot® version 14.0, Microsoft Excel® version 2016, interpolation log, and direct interpolation methods were employed to estimate the EC 50 values. Linear regression and direct interpolation results showed deviations for non-linear models in the prediction of EC 50 values of grape extracts. The correlation results of grape flesh extracts demonstrated a positive correlation (r = ≥ 0.95) between EC 50 values of antioxidant assays. Therefore, non-linear methods were appropriate for EC 50 calculations. These findings have significant implications for selecting an efficient statistical tool to calculate EC 50 values for DPPH and ABTS assays. [ABSTRACT FROM AUTHOR]

Most of the fast in vitro assays proposed to determine the antioxidant capacity of a compound/extract lack either biological context or employ complex protocols. Therefore, the present work proposes the improvement of an agarose gel DNA electrophoresis in order to allow for a quantitative estimation of the antioxidant capacity of pure phenolic compounds as well as of a phenolic rich extract, while also considering their possible pro-oxidant effects. The result obtained demonstrated that the proposed method allowed for the evaluation of the protection of DNA oxidation [in the presence of hydrogen peroxide (H 2 O 2 ) and an H 2 O 2 /iron (III) chloride (FeCl 3 ) systems] as well as for the observation of pro-oxidant activities, with the measurements registering interclass correlation coefficients above 0.9. Moreover, this method allowed for the characterization of the antioxidant capacity of a blueberry extract while demonstrating that it had no perceived pro-oxidant effect. [ABSTRACT FROM AUTHOR]

The leaves of Linderae aggregate (LAL) has been used as a type of tea in China and other Southeast Asian countries. In this study, 11 polyphenols in LAL were clarified for the first time using multiple high-performance liquid chromatographic techniques. An optimal extracting method was developed through the comparison of the amount of quercetin-3- O -α- l -rhamnoside using a uniform design method. From the fingerprint liquid chromatography data, 11 common peaks in the 8 samples collected from April to November were semi-determined. The antioxidant capacities were examined using the 2,2-diphenyl-1-picrylhydrazyl free radical scavenging assay and the ferric reducing/antioxidant power assay. All 8 samples contained the same 11 polyphenols in similar ratios. Three samples, S2, S5 and S6 contained higher amount of quercetin-3- O -α- l -rhamnoside and were demonstrated to have stronger antioxidant capacities in both antioxidant assays. These results are critical in optimising harvest time and quality control of LAL. [ABSTRACT FROM AUTHOR]

Highlights: [•] Extracts of all the developmental stages exhibited high antioxidant activities. [•] Cell death via apoptosis was caused maximum with floret extract. [•] Organosulfuric compounds in extracts may be responsible for observed activities. [Copyright &y& Elsevier]

Abstract: Antioxidant potential of four methanol extracts from three selected plant species, namely Salvia nubicola (Lamiaceae), Acer oblongifolium (Aceraceae) and Hedera nepalensis (Araliaceae) was measured using assays in aqueous and lipid systems. Antioxidant activities were investigated in aqueous systems by using DPPH radical-scavenging assay, ABTS radical-scavenging assay and DNA protection assay, while antioxidant activity in a lipid system was determined by using the thiobarbituric acid-reactive substances (TBARS) assay. Additionally, the Folin-Ciocalteu method was used to measure total phenolic content. Methanol extracts of leaves and flowers of S. nubicola showed the highest Trolox equivalent (TE) values in the case of the DPPH assay, 2484±4.9mmol TE/g extract, as well as total phenolic content, 139±0.2mg gallic acid equivalents/g extract. Three fractions (A–C) of the methanol extract of S. nubicola leaves and flowers were produced by semi-preparative HPLC. Fraction B was found to be the most active in the DPPH radical-scavenging assay and had the highest total phenol content. HPLC-DAD and LC–MS revealed rosmarinic acid in S. nubicola extracts and chlorogenic acid and rutin in H. nepalensis extracts as the main phenolic antioxidants. [Copyright &y& Elsevier]

Abstract: The antioxidant potency of acetone extract/fractions of Acacia auriculiformis A. Cunn. was investigated by employing various in vitro systems, such as DPPH, deoxyribose (site- and non-site-specific), reducing power, chelating power and lipid peroxidation in rat liver homogenate. The bark powder of the plant was extracted with different solvents by a maceration method in order of increasing and decreasing polarities and then partitioned (). It was observed that the fractions were comparatively more effective than the crude acetone extract in all the assays. Maximum inhibitory activities noticed were 72.3%, 91.7%, 1.63, 83.3%, and 70.9% in DPPH, deoxyribose, reducing power, chelating power and lipid peroxidation assays, respectively. The inhibitory potential was compared with known antioxidants (ascorbic acid and BHT) and correlated with the total phenolic content in crude extract and fractions. Fractions rich in polyphenolic content were more effective than crude extract. Further studies are underway to isolate and elucidate the structures of the active principles. [Copyright &y& Elsevier]