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High rates of oxidation during hydrolysis are one the main problems with hydrolysate production from fatty fishes such as Sind sardines. The purpose of this study was to control oxidation by different pretreatments with pistachio green hull (PGH) extracts as an antioxidant. Different enzyme levels (1.3%, 2.5%, and 5%), pretreatments of fish mince (washing, defatting, fish protein isolate (FPI)), and the addition of PGH as well as nitrogen gas treatment were studied on lipid oxidation during hydrolysis of Sind sardines (Sardinella sindensis). The antioxidant properties of the hydrolysates were also studied. Results for thiobarbituric acid reactive substances indicated that the nitrogen gas and 5% (w/w) enzymatic treatment significantly decreased lipid oxidation along with having a higher degree of hydrolysis and higher antioxidant activity for the hydrolysate. FPI was more effective than washing in controlling oxidation while defatting using isopropanol was the most effective. PGH (260 µg/ml) effectively controlled the oxidation of mince and washed mince (P

Antioxidants remain interesting molecules of choice for suppression of the toxic effects of free radicals in foods and human systems. The current practice involves the use of mainly synthetic molecules as potent antioxidant agents. However, due to the potential negative impact on human health, there is an intensive effort within the research community to develop natural alternatives with similar antioxidant efficacy but without the negative side effects of synthetic molecules. Still, the successful development of new molecules depends on the use of reliable chemical or cell culture assays to screen antioxidant properties. Chemical antioxidant assays include the determination of scavenging ability against free radicals such as DPPH, superoxide anion radicals, hydroxyl radicals, hydrogen peroxide, and nitric oxide. Other antioxidant tests include the ability of compounds to bind and sequester prooxidant metal cations, reduce ferric iron, and attenuate the rate of lipid oxidation. Ex vivo tests utilize cell cultures to confirm entry of the molecules into cells and the ability to quench synthetic intracellular free radicals or to stimulate the increased biosynthesis of endogenous antioxidants. In order to assist researchers in their choice of antioxidant evaluation methods, this review presents background scientific information on some of the most commonly used antioxidant assays with a comparative discussion of the relevance of published literature data to food science and human nutrition applications.

The prevalence of diabetes mellitus, a chronic disease characterized by marked alterations in energy homeostasis, is increasing at rapid rates globally, fuelled in part by the obesity epidemic. Although diabetes can be managed using multi-drug therapies, the process is costly and is associated with negative side effects. Therefore, there is growing support for research examining the potential use of functional foods, specifically dietary peptides, for the treatment of diabetes in a safer and more cost-effective manner. This chapter summarizes and interprets the current understanding of bioactive food peptide production and analysis. Furthermore, the effects of milk-, soybean- and egg-derived bioactive peptides on energy and glucose homeostasis are examined in preclinical and clinical models of insulin resistance and type 2 diabetes.

Iron, zinc, and calcium are essential micronutrients that play vital biological roles to maintain human health. Thus, their deficiencies are a public health concern worldwide. Mitigation of these deficiencies involves micronutrient fortification of staple foods, a strategy that can alter the physical and sensory properties of foods. Peptide–mineral complexes have been identified as promising alternatives for mineral-fortified functional foods or mineral supplements. This review outlines some of the methods used in the determination of the mineral chelating activities of food protein-derived peptides and the approaches for the preparation, purification and identification of mineral-binding peptides. The structure–activity relationship of mineral-binding peptides and the potential use of peptide–mineral complexes as functional food ingredients to mitigate micronutrient deficiency are discussed in relation to their chemical interactions, solubility, gastrointestinal digestion, absorption, and bioavailability. Finally, insights on the current challenges and future research directions in this area are provided.

Phenolic compounds as agro-industrial by-products have been associated with health benefits since they exhibit high antioxidant activity and anti-diabetic properties. In this study, polyphenol-rich extract from pistachio green hull (PGH) was evaluated for antioxidant activity and its ability to inhibit α-amylase and α-glucosidase activity in vitro. The effect of PGH extract powder on in vitro starch digestibility was also evaluated. The results showed that PGH had stronger antioxidant activity than Trolox. The inhibitory effect of PGH extract against α-amylase from porcine pancreas was dose dependent and the IC50 value was ~174μgGAE/mL. The crude PGH extract was eight times more potent on baker yeast α-glucosidase activity (IC50~6μgGAE/mL) when compared to acarbose, whereas the IC50 value of PGH extract against rat intestinal maltase activity obtained ~2.6mgGAE/mL. The non-tannin fraction of PGH extract was more effective against α-glucosidase than tannin fraction whereas the α-amylase inhibitor was concentrated in the tannin fraction. In vitro starch digestibility and glycemic index (GI) of pasta sample supplemented with PGH extract powder (1.5%) was significantly lower than the control pasta. The IC50 value of PGH extract obtained from cooked pasta against α-amylase and α-glucosidase was increased. These results have important implications for the processing of PGH for food industry application and therefore could comply with glucose control diets.

Potato processing effluents represent a potential source of valuable proteins for the production of bioactive peptides. In this study, potato protein was hydrolyzed with Alcalase and fractionated using ultrafiltration (10, 2 kDa molecular weight cut off) and adsorption chromatography (adsorbent resin XAD-16 column). Potato protein hydrolysates (PHM and PHC), membrane fractions PHR1 (>10 kDa), PHR2 (2–10 kDa) and PHR3 (

This study investigated the effects of protease type (Alcalase, papain and pepsin), fractionation (2 and 10 kDa nominal molecular weight cutoff) and pistachio green hull (PGH) extract addition on antioxidant activity (DPPH radical scavenging and metal chelating activity), α-glucosidase, α-amylase, and dipeptidyl peptidase IV (DPP-IV) inhibitory activity of Sind sardine hydrolysates. Papain led to the highest degree of hydrolysis and antioxidant activity and the addition of PGH enhanced the bioactivity. Hydrolysates and fractions had stronger inhibition of α-amylase than α-glucosidase, and hydrolysates from papain and Alcalase were more active than those from pepsin against α-amylase. Interaction of PGH and the hydrolysates/peptidic fractions resulted in a decrease in α-glucosidase and α-amylase inhibition. The kinetics of α-amylase inhibition with papain hydrolysates and papain-PGH showed competitive inhibition. Hydrolysates and fractions also significantly inhibited DPP-IV, but PGH did not inhibit the enzyme or change the inhibitory effect of the hydrolysates and fractions (P ≥ 0.05). Furthermore, the highest surface hydrophobicity was observed for the >10 kDa fractions and the values increased by the addition of PGH to the hydrolysates. Therefore, PGH–hydrolysate interaction improved only the antioxidant capacity of the protein hydrolysates with nil or negative effects on the enzyme inhibition.

Svrha je ovog istraživanja bila procijeniti svojstva dvaju tipova prebiotičkih kobasica, pripremljenih s rezistentnim škrobom i ekstraktom β-glukana (u omjerima 2,216:1,328 i 2,75:1,875), tijekom prženja i skladištenja pri niskim temperaturama. Određeni su indeksi oksidacijske stabilnosti i broj mikroorganizama. Dodatak dvaju prebiotičkih dijetalnih vlakana povećao je gubitke pri prženju i adsorpciju ulja. Međutim, količina vlage u prebiotičkim kobasicama nakon proizvodnje bila je veća u usporedbi sa standardnim (neprebiotičkim) kobasicama, te se postepeno smanjivala tijekom skladištenja. Rezultati pokazuju da dodatak preporučenog omjera rezistentnog škroba i β-glukana (2,216:1,328) može dovesti do smanjenja oksidacije masti u kobasicama tijekom skladištenja zbog antioksidacijskih svojstava ekstrakta β-glukana, no dodatak većih količina rezistentnog škroba i β-glukana nije moguć zbog daljnjeg porasta oksidacije masti. Konačan broj živih stanica rastao je do četrdeset i petog dana, nakon čega je došlo do njegovog postepenog pada. Dodatak ekstrakta β-glukana poboljšao je antioksidacijska svojstva proizvoda. Također, njegov antimikrobni učinak i smanjenje udjela vlage mogli bi inhibirati rast mikroorganizama. Nadalje, dodatak rezistentnog škroba doveo je do povećanja tiobarbiturnog i peroksidnog broja., This study aims to evaluate the performance of two types of prebiotic sausages formulated with resistant starch (RS) and β-glucan (BG) extract (in ratios of 2.22:1.33 and 2.75:1.88) during frying and chilled storage. The oxidative stability indices and microbial counts were determined. The incorporation of two types of prebiotic dietary fibre increased frying loss and oil absorption. However, the moisture content of prebiotic sausages after production was higher than of conventional sausages and it decreased significantly during storage. The use of sausage sample containing 2.22 % RS and 1.33 % BG as a recommended formulation can decrease fat oxidation of sausages during storage due to antioxidant properties of BG extract, but higher levels of RS and BG could not be used due to further increase in fat oxidation. Total viable count increased up to day 45 and decreased afterwards. The addition of BG extract improved the antioxidant properties of sausages. Additionally, the antimicrobial properties of BG and moisture reduction could inhibit microbial growth. Moreover, the addition of RS caused an increase in thiobarbituric acid and peroxide values.

This study investigated the fortification of bread with 1, 2, and 4 g/100 g of maize germ protein hydrolysate (MGPH) for enhancement of in vitro antioxidant potential of the bread before and after digestion and α-amylase inhibition during digestion. Furthermore, color, moisture content and texture profile of the fortified bread were assessed. Hydrolysate addition at 4 g/100 g increased DPPH˙ scavenging activity and Fe2+ chelating activity of the bread ~2.3 and 2.1 times compared to control, respectively. After simulated digestion, DPPH˙ scavenging activity increased ~4 time while the Fe2+ chelating activity decreased significantly (p

An effective strategy for controlling postprandial hyperglycemia and type 2 diabetes is by inhibiting the activity of α-amylase and α-glucosidase using natural inhibitors. In current study, the in vitro inhibitory potential of pomegranate peel extract (PPE) against α-amylase and α-glucosidase activity was investigated. The impact of PPE (0.5, 1, and 1.5 g/100 g) on starch digestibility, glycemic index (GI), the color, texture and sensory properties of sponge cakes was determined. The IC50 value for porcine α-amylase inhibition was 70.3 ± 1.98 μg/mL. The IC50 value for inhibition of α-glucosidase from rat intestines (6140 ± 85.1 μg/mL) was significantly higher than that from Saccharomyces cerevisiae (18.75 ± 1.12 μg/mL) (P

This study aimed to investigate the effect of partial fat replacement with two species of gum tragacanth (Astragalus gossypinus and Astragalus compactus) on physicochemical, textural, oxidative stability, and acceptability of reduced fat emulsion type sausages. Increasing the concentration of both gums to 1%, minimized extractable fat and cook loss. A. gossypinus at the concentration of 1% was the most effective in retardation of TBARS formation in sausages (p 0.05). Reduced-fat sausages with 1% A. gossypinus showed the lowest carbonyls at the end of storage (28 days) (p 0.05). Sausages with 1% A. gossypinus or A. compactus showed the lowest shear force (~6 and ~7 N respectively) and hardness (~21 N/cm

Background: Propolis is a natural product of bee and caffeic acid phenethyl ester (CAPE) is a pharmacologically important product of propolis. Objectives: The aim of this study was to investigate the effect of CAPE on apoptosis induction in AGS human gastric cancer cells. Materials and Methods: The cytotoxic effects of CAPE at different concentrations were investigated on AGS cells viability after 24 hours treatment by MTT assay. To measure the effect of CAPE on apoptosis induction, AGS cells were treated with CAPE for 24 hours and investigated by FITC Annexin V/PI staining using flow cytometry. Results: CAPE prevented growth and proliferation of AGS human gastric cancer cell line in a concentration-dependent manner with an IC50 of approximately 60 µM by a 24-hour treatment. Also CAPE caused increased induction of apoptosis in AGS cells from 1.37 % in control cells to 21.76 % in treated cells with 30 µM CAPE. Conclusions: CAPE prevents growth and proliferation of AGS human gastric cancer cell line through inducing programmed cell death in AGS cells. Therefore, CAPE could be helpful for developing chemotherapeutic agents or as an adjuvant for human gastric cancer treatment.