Phenolic composition,antioxidant capacity and inhibitory effects on α-glucosidase and lipase of immature faba bean seeds

Immature faba bean seeds of five varieties were investigated for changes in phenolic composition, antioxidant capacity and inhibitory effects on α-glucosidase and lipase at three edible stages (S1, S2 and S3). Phenolics and antioxidant capacity in seed coats were significantly higher than those in cotyledons, and the highest was found of FD18 at stage S3. While phenolic content in cotyledons decreased steadily with the harvest time delayed. Eight phenolic compounds were confirmed with epicatechin and catechin prominent and their levels showed a great variability depending on varieties, maturation stages and plant parts of faba bean seeds. Unexpectedly, the inhibitory effects of purified phenolics on α-glucosidase were even stronger than that of the positive control acarbose, and the inhibitory effects on lipase in the cotyledons declined gradually from stage S1 to S3. Significant positive correlations between phenolics from seed coats and antioxidant capacity, and phenolics from cotyledons and the enzyme inhibitory effects were observed. Overall, the immature faba bean seed, especially its seed coat, has great potential as a functional food.     

Thermal inactivation of lactoperoxidase in goat,sheep and bovine milk – A comparative kinetic and thermodynamic study

Using isothermal heating, inactivation of lactoperoxidase (LPO) in goat, sheep and cow milk was studied in the temperature range of 70–77 °C. Kinetic and thermodynamics studies were carried out at different time–temperature combination in order to evaluate the suitability of LPO as marker for the heat-treatment of milk and dairy products from different species. The thermal inactivation of LPO followed the first-order kinetics. D- and k-values decreased and increased, respectively with increasing temperature, indicating a more rapid LPO inactivation at higher temperatures. The influence of temperature on the inactivation rate constant was quantified using the Arrhenius and thermal death time models. The corresponding z-values were 3.38 ± 0.013, 4.11 ± 0.24 and 3.58 ± 0.004 °C in goat, sheep and cow milk, respectively. Activation energy values varied between milk species with 678.96 ± 21.43 kJ mol⁻¹ in goat milk, 560.87 ± 28.18 kJ mol⁻¹ in sheep milk and 641.56 ± 13.12 kJ mol⁻¹ in cow milk, respectively.     

Polymeric proanthocyanidins in skins and seeds of 37 Vitis vinifera L. cultivars: a methodological comparative study

Abstract: The polymeric proanthocyanidins (PAs) composition of skins and seeds from different Vitis vinifera L. cv. was evaluated, sampling 37 cultivar, preserved in the grapevine collection of Grinzane Cavour (Piedmont, Italy). PAs were quantified using both spectrophotometric (n‐butanol and vanillin assay) and chromatographic (high‐performance liquid chromatography [HPLC]) methods, and the evaluation of their antioxidant activity was performed using the 2,2‐diphenyl‐1‐picrylhydrazyl (DPPH) scavenging assay. Results of PAs quantification with the different methods were significantly correlated. A strong correlation pointed out between anthocyans and PAs content (particularly regarding HPLC method; r = 0.9359, P = 0), and the antioxidant activity was not dependent on the polymeric PAs content, but negatively correlated with the degree of polymerization (r =–0.6102, P = 1 × 10^?4). The hierarchical clustering on principal components analysis allowed grouping the samples in 3 different clusters, observing a direct association between the cluster classification and the anthocyans/PAs content.     

Does the lipid membrane composition of arsonoliposomes affect their anticancer activity? A cell culture study

Sonicated arsonoliposomes were prepared using arsonolipid with palmitic acid acyl chain (C16), mixed with phosphatidylcholine (PC)-based or 1,2-distearoyl-sn-glycero-3-phosphocholine (DSPC)-based, and cholesterol (Chol) with C16/DSPC/Chol 8:12:10 molar ratio. PEG-lipid (1,2-distearoyl-sn-glycero-3-phosphoethanolamine conjugated to polyethylenoglycol 2000) containing vesicles (PEGylated-arsonoliposomes; PC-based and DSPC-based) were also prepared. The cytotoxicity of these arsonoliposomes towards different cancer cells (human promyelocytic leukaemia NB4, Prostatic cancer PC3, human breast adenocarcinoma MDA-MB-468, human T-lymphocyte (MT-4) and also towards human umbilical vein endothelial cells (HUVECs) was evaluated by calculating the arsonoliposome-induced growth inhibition of the cells by the MTT assay. IC-50 values were interpolated from cell number/arsonoliposome concentration curves. The results reveal that all types of arsonoliposomes evaluated significantly inhibit the growth of most of the cancer cells studied (PC3, NB4, MT4) with the exception of the MDA-MB-468 breast cancer cells which were minimally affected by arsonoliposomes; in some cases even less than HUVEC. Nevertheless, for the same cell type the differences between the different types of arsonoliposomes were significant but not proportional to their stability, indicating that the formation of arsonoliposomes with very stable membranes is not a problem for their anticancer activity. Thereby it is concluded that arsonoliposome composition should be adjusted in accordance to their in vivo kinetics and the desired, for each specific application, biodistribution of As and/or encapsulated drug.     

LC-MS–MS characterisation of curry leaf flavonols and antioxidant activity

Curry leaf (Murraya koenegii) is a common flavouring agent in Indian foods. This study characterised the flavonol profile of curry leaf extracted with different solvents and the relative antioxidant capacity of these extracts by quantifying phenolic constituents. Flavonols were extracted using ethanol, methanol, or acetone prior to identification and quantification using liquid chromatography coupled to atmospheric pressure chemical ionisation (APCI) mass spectrometry in tandem mode (LC-MS–MS) with negative ion detection. Major curry leaf flavonols included myricetin-3-galactoside, quercetin-O-pentohexoside, quercetin-3-diglucoside, quercetin-3-O-rutinoside, quercetin-3-glucoside, quercetin-3-acetylhexoside, quercetin-O-xylo-pentoside, kaempferol-O-glucoside, and kaempferol-aglucoside. Lag-time and TBARS tests demonstrated that curry leaf phenolics prevent cupric-ion induced oxidation of LDL. The best extraction yield was obtained with 80% ethanol. Acetone extracts provided better antioxidant activity expressed as increased lag-time formation, than did ethanol or methanol extracts. Curry leaf is a rich source of flavonols that have biological activity in vitro and further studies are warranted in regards to the potential health benefits and identification of the novel flavonols whose identities remain unknown.     

Bean cultivars (Phaseolus vulgaris L.) have similar high antioxidant capacity,in vitro inhibition of α-amylase and α-glucosidase while diverse phenolic composition and concentration

Common beans are a good source of essential nutrients such as protein, fiber, vitamins, and minerals; they also contain phenolic compounds and other phytochemicals. Phenolic compounds exhibit high antioxidant capacity that promotes health benefits by reducing oxidative stress. The objective was to compare the composition and quantity of anthocyanins and other non-colored phenolic compounds in fifteen improved bean cultivars from Mexico and Brazil and their relation to antioxidant capacity and enzymes related to type-2 diabetes. Samples were analyzed for total phenolic compounds (TP), flavonoids, antioxidant capacity (AC), tannins and total anthocyanins. Type and quantity were evaluated by HPLC-ESI-MS. Delphinidin glucoside (0.9–129.0 mg/100 g dry coat), petunidin glucoside (0.7–115.0 mg/100 g dry coat) and malvidin glucoside (0.14–52.0 mg/100 g dry coat). Anthocyanidins were positively correlated when quantified by HPLC and colorimetric analysis (R = 0.99). Cultivar Negro-Otomi presented the highest concentration of anthocyanins (250 mg/100 g dry coat). Seventeen non-colored phenolic compounds were identified among cultivars; catechin, myricetin 3-O-arabinoside, epicatechin, vanillic acid, syringic acid and o-coumaric acid, presented the highest concentrations among identified phenolic compounds. The AC of all fifteen bean cultivars did not show significant differences (p > 0.05) ranging from 185.2 (FM-67) to 233.9 (FM-199) mmol TE/g coat. Compounds in the coat extracts of pinto and black cultivars were the most efficient to inhibit α-amylase and α-glucosidase. Studied cultivars differed in composition and concentration of phenolics including anthocyanins; however, there was no effect on AC as measured by oxygen radical absorbance capacity. Black beans contained delphinidin and ferulic acid, compounds commonly used as ingredients in functional foods due to their associated health benefits.     

Nutrient composition and physicochemical properties of Indian medicinal rice – Njavara

Njavara, a medicinal rice, was assessed for its nutrient composition and physicochemical properties, in order to understand its therapeutic properties. Dehusked Njavara rice consisted of 73% carbohydrates, 9.5% protein, 2.5% fat, 1.4% ash and 1628 kJ per 100 g of energy. Physicochemical properties and nutritive components of dehusked rice of Njavara were evaluated and compared with two commonly consumed non-medicinal rice varieties – Jyothi (red coloured) and IR 64 (brown coloured). The carbohydrates, fats, apparent amylose equivalent, fatty acid profile and triglycerides of Njavara were comparable to Jyothi and IR 64. However, Njavara rice had 16.5% higher protein, and contained higher amounts of thiamine (27–32%), riboflavin (4–25%) and niacin (2–36%) compared to the other two rice varieties. The total dietary fibre content in Njavara was found to be 34–44% higher than that of Jyothi and IR 64. Significantly higher phosphorus, potassium, magnesium, sodium and calcium levels were found in Njavara rice, compared to the other two varieties. The cooking time of dehusked Jyothi and IR 64 varieties were found to be 30 min, while Njavara needed longer time to cook, (38 min). The cooked rice of Njavara was slimy in nature, probably due to the presence of non-starch polysaccharides.     

Phenolic content,antioxidant capacity,and α-amylase and α-glucosidase inhibitory activities of Dimocarpus longan Lour.

Food Science and Biotechnology - The aim of this study was to compare the phenolic compound profiles and antioxidant capacities of eight varieties of longan (Dimocarpus longan Lour.) planted in the...     

Phenolic compounds’ characterization of Artemisia rutifolia spreng from Pakistani flora and their relationships with antioxidant and antimicrobial attributes

Artemisia rutifolia (Asteraceae) had been used in traditional medicines for the treatment of different ailments. In the current study, an effort was made to explore the phenolic composition, antioxidant, and antimicrobial activities of different solvent extracts obtained from A. rutifolia leaves. The reverse-phase high-performance liquid chromatographic (RP-HPLC) analysis revealed the higher extent of polyphenolic compounds (i.e., gallic acid, caffeic acid, chlorogenic acid, syringic acid, sinapic acid, p-coumaric acid, m-coumaric acid, ferulic acid, vanillic acid, myricetin, and quercetin) in methanol extract. Methanol extract consistently showed the highest total phenolic contents (98 ± 2 µg GAE/mg of plant extract), total flavonoid contents (28 ± 0.0 µg QE/mg of plant extract), antimicrobial activity, free radical (DPPH) scavenging (IC₅₀ = 39 µg/mL) activity, and reducing power (18.3 ± 0.2 mg GAE/g of plant extract) followed by those of chloroform and hexane extracts, respectively. The current study concluded that extracts of A. rutifolia are novel natural source of antioxidative and antimicrobial agents for the treatment of oxidative stress-related disorders and microbial infections.     

Structure–activity relationship and molecular docking analysis of cysteine-containing dipeptides as antioxidant and ACE inhibitory

Comparative molecular field analysis (CoMFA), comparative similarity index analysis (CoMSIA) and hologram QSAR (HQSAR) were used to identify the relationship between the structure of cysteine-containing dipeptide with antioxidant and ACE inhibitory activity; then, molecular docking, ADME prediction and thermostability assay were applied to illustrate the performance in docking with ACE, metabolic information and thermostability of the strongest activity dipeptide. According to pIC₅₀ of 2, 2-diphenyl-1-picrylhydrazyl (DPPH) and 2, 2′-azinobis-(3-ethyl-benzothiazoline-6-sulphonate) (ABTS), constructed CoMFA, CoMSIA and HQSAR models predicted the structural properties of carboxyl of C-terminus impacted on the antioxidant activity. The properties of side chain of C-terminus influenced on the ACE inhibitory activity based on CoMFA, CoMSIA and HQSAR models. As the strongest multifunctional cysteine-containing dipeptide, CW interacted with ACE by S1 pocket, S2 pocket, Zn²⁺. It was promising for CW to utilise in the functional foods due to less interference in normal life activities, high oral bioavailability and stability under 70 °C.     

Effect of thermal and high pressure processing on antioxidant activity and instrumental colour of tomato and carrot purées

Total antioxidant activity, levels of bio-active compound groups and instrumental colour of tomato and carrot purée subjected to high pressure treatment (400–600 MPa/15 min/20 °C) and thermal treatments (70 °C/2 min) were measured. Antioxidant activity in tomato and carrot purée was significantly higher (p < 0.05) than in untreated or thermally processed samples. High pressure treatments at 600 MPa retained more than 90% of ascorbic acid as compared to thermal processing in tomato purées. Heat treatments caused a rapid decrease in ascorbic acid (p < 0.05). Phenolic contents were in general un-affected by thermal or high pressure treatments. Colour parameters were significantly affected (p < 0.05) by thermal and high pressure processing. Principal component analysis (PCA) revealed that the first two components represented 97% and 92% of the total variability in instrumental colour parameters with respect to processing for tomatoes and carrots respectively.Industrial relevanceThis research paper provides scientific evidence of the potential benefits of high pressure processing in comparison to thermal treatments in retaining important bioactive compounds. Antioxidant activity (ARP), ascorbic acid, and carotenoids after exposure to high pressure treatments (400–600 MPa) were well retained. Our results also show that redness and colour intensity of purées were better preserved by high pressure processing than conventional thermal treatment. It would appear from a nutritional prospective, high pressure processing is an excellent food processing technology which has the potential to retain compounds with health properties in foods. Therefore high pressure processed foods could be sold at a premium over their thermally processed counterparts as they will have retained their fresh-like properties.     

Structure of modified ε-polylysine micelles and their application in improving cellular antioxidant activity of curcuminoids

The micelle structure of octenyl succinic anhydride modified ε-polylysine (M-EPL), an anti-microbial surfactant prepared from natural peptide ε-polylysine in aqueous solution has been studied using synchrotron small-angle X-ray scattering (SAXS). Our results revealed that M-EPLs formed spherical micelles with individual size of 24-26 ? in aqueous solution which could further aggregate to form a larger dimension with averaged radius of 268-308 ?. Furthermore, M-EPL micelle was able to encapsulate curcuminoids, a group of poorly-soluble bioactive compounds from turmeric with poor oral bioavailability, and improve their water solubility. Three loading methods, including solvent evaporation, dialysis, and high-speed homogenization were compared. The results indicated that the dialysis method generated the highest loading capacity and curcuminoids water solubility. The micelle encapsulation was confirmed as there were no free curcuminoid crystals detected in the differential scanning calorimetry analysis. It was also demonstrated that M-EPL encapsulation stabilized curcuminoids against hydrolysis at pH 7.4 and the encapsulated curcuminoids showed elevated cellular antioxidant activity compared with free curcuminoids. This work suggested that M-EPL could be used as new biopolymer micelles for delivering poorly soluble drugs/phytochemicals and improving their bioactivities.     

Time resolved fluorescence of milk powders – A pilot study

The investigation of the authenticity and classification of milk powder is particularly important. The use of time-resolved fluorescence could help develop a new method to assist milk powder classification and assess composition. This study used static and time-resolved fluorescence to differentiate powder milk samples. We observed fluorescence lifetimes of (in ns) 1.5 ± 0.2, 3.5 ± 0.2 and 6.0 ± 0.2 for skimmed; 1.3 ± 0.2, 3.3 ± 0.2 and 6.0 ± 0.4 for whole; and 1.4 ± 0.2, 3.4 ± 0.3 and 6.0 ± 0.4 for semi-skimmed powder milk at 270/335 nm excitation/emission. In addition, we observed fluorescence lifetimes of (in ns) 1.4 ± 0.1, 6.4 ± 0.2 and 14.8 ± 1.1 for skimmed; 1.6 ± 0.2, 6.8 ± 0.2 and 29.5 ± 1.7 for whole; and 1.7 ± 0.1, 6.8 ± 0.2 and 26.1 ± 1.3 for semi-skimmed powder milk at 315/468 nm excitation/emission. Employing analysis of variance, we differentiated all powder samples and achieved accuracy of 100% by discriminant analysis at 315/468 nm excitation/emission fluorescence. These results indicate that time-resolved fluorescence can assist in the classification of powder milk and its composition.     

Prevalence and diversity of histamine-forming Lactobacillus parabuchneri strains in raw milk and cheese – A case study

In the present case study, we investigated the causes of consistently elevated histamine content in raw milk cheeses from a Swiss cheese dairy. Screenings of milk samples from 67 farmers revealed that 19.1% of the raw milk samples were contaminated with histamine-forming bacteria. Lactobacillus parabuchneri was detected in 97.4% of contaminated milk samples. The population density of L. parabuchneri was almost always below the limit of quantification of the qPCR method used. Genotyping of 469 isolates provided detailed insight into the diversity of L. parabuchneri in contaminated milks and cheeses. The results of the trace-back study clearly demonstrated that several milk suppliers were responsible for the histamine problem at the cheese dairy under study. Systematic controls of milking systems allowed persistent contamination sources of L. parabuchneri at the farm level to be identified and eliminated and thereby to reduce the percentage of contaminated milks to 8.5% within the study period.     

Green tea extract: Chemistry,antioxidant properties and food applications – A review

Green tea is one of the most popular and extensively used dietary supplement in the United States. Diverse health claims have made for green tea as a trendy ingredient in the growing market for nutraceuticals and functional foods. Green tea extract contains several polyphenolic components with antioxidant properties, but the predominant active components are the flavanol monomers known as catechins, where epigallocatechin-3-gallate and epicatechin-3-gallate are the most effective antioxidant compounds. Additional active components of green tea extract include the other catechins such as epicatechin and epigallocatechin. Among these, epigallocatechin-3-gallate is the most bioactive and the most scrutinized one. Green tea polyphenols are also responsible for distinctive aroma, color and taste. Green tea extract can also be used in lipid-bearing foods to delay lipid oxidation and to enhance the shelf-life of various food products. This review outlines the chemistry, flavour components, antioxidant mechanism, regulatory status, food applications, and stability of green tea extract in food.     

Superfruits: Phytochemicals,antioxidant efficacies,and health effects – A comprehensive review

The term “superfruit” has gained increasing usage and attention recently with the marketing strategy to promote the extraordinary health benefits of some exotic fruits, which may not have worldwide popularity. This has led to many studies with the identification and quantification of various groups of phytochemicals. This contribution discusses phytochemical compositions, antioxidant efficacies, and potential health benefits of the main superfruits such as açai, acerola, camu-camu, goji berry, jaboticaba, jambolão, maqui, noni, and pitanga. Novel product formulations, safety aspects, and future perspectives of these superfruits have also been covered. Research findings from the existing literature published within the last 10 years have been compiled and summarized. These superfruits having numerous phytochemicals (phenolic acids, flavonoids, proanthocyanidins, iridoids, coumarins, hydrolysable tannins, carotenoids, and anthocyanins) together with their corresponding antioxidant activities, have increasingly been utilized. Hence, these superfruits can be considered as a valuable source of functional foods due to the phytochemical compositions and their corresponding antioxidant activities. The phytochemicals from superfruits are bioaccessible and bioavailable in humans with promising health benefits. More well-designed human explorative studies are needed to validate the health benefits of these superfruits.