Ferrous Chelating Ability Research Articles

Pitahaya (Hylocereus ocamponis)-Peel and -Flesh Flour Obtained from Fruit Co-Products-Assessment of Chemical, Techno-Functional and In Vitro Antioxidant Properties.

The aim of this work was to assess the chemical composition and physico-chemical, techno-functional, and in vitro antioxidant properties of flours obtained from the peel and flesh of pitahaya (Hylocereus ocamponis) to determine their potential for use as ingredients for food enrichment. The chemical composition, including total betalains, mineral content, and polyphenolic profile, was determined. The techno-functional properties (water holding, oil holding, and swelling capacities) were also evaluated. For the antioxidant capacity, four different methodologies, namely ferrous ion-chelating ability assay, ferric-reducing antioxidant power assay; 1,1-Diphenyl-2-picrylhydrazyl radical scavenging ability assay, and 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) radical assay, were used. Pitahaya-peel flour had higher values for protein (6.72 g/100 g), ash (11.63 g/100 g), and dietary fiber 56.56 g/100 g) than pitahaya-flesh flour, with values of 6.06, 3.63, and 8.22 g/100 g for protein, ash, and dietary fiber, respectively. In the same way, pitahaya peel showed a higher content of minerals, betalains, and polyphenolic compounds than pitahaya-flesh flour, with potassium (4.43 g/100 g), catechin (25.85 mg/g), quercetin-3-rhamnoside (11.66 mg/g) and myricetrin (12.10 mg/g) as principal compounds found in the peel. Again, pitahaya-peel flour showed better techno-functional and antioxidant properties than pitahaya-flesh flour. The results obtained suggest that the flours obtained from the peel and pulp of pitahaya (H. ocamponis) constitute a potential material to be utilized as an ingredient in the food industry due to the high content of bioactive compounds such as betalains, phenolic acids, and flavonoids, with notable antioxidant capacity.

Enhanced Enzymatic Production of Antioxidant Peptides from Carya cathayensis Cake Using an Enzymatic Membrane-Coupled Reactor

This study establishes an enzymatic membrane-coupled production process for antioxidant peptides from Carya cathayensis cake by comparing the effects of not feeding, water feeding, substrate feeding, and gradient dilution feeding supplementary material modes, to assess their impact on production efficiency. The optimal operational conditions were determined as follows: pH 10.5, temperature 50 °C, and enzyme-to-substrate ratio of 10% (w/w). The continuous production using the gradient dilution supplementary material mode resulted in Chinese pecan antioxidant peptides with 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging rate of 0.044 mg/mL, 2, 2-azinobis-(3-ethylbenzthiazoline-6-sulfonate) (ABTS) radical scavenging rate of 0.518 mg/mL, and ferrous ion chelating ability (IC50) of 0.252 mg/mL. Compared with traditional enzymatic hydrolysis processes, the gradient dilution supplementary material enzymatic membrane-coupled production process increased peptide yield, peptide production, and unit enzyme-peptide production by 14.36%, 11.35%, and 235.63%, respectively. This continuous production method facilitates scalability, enabling the production of high-yield and high-activity Carya cathayensis cake peptides, making better use of byproducts after oil extraction, and laying a solid foundation for the comprehensive development and deep processing of Chinese pecan, thus enhancing its economic value.

Study on the anti-inflammatory activity of the porcine bone collagen peptides prepared by ultrasound-assisted enzymatic hydrolysis

In this study, the effects of ultrasound-assisted enzymatic hydrolysis on the extraction of anti-inflammatory peptides from porcine bone collagen were investigated. The results showed that ultrasound treatment increased the content of α-helix while decreased β-chain and random coil, promoted generation of small molecular peptides. Ultrasound-assisted enzymatic hydrolysis improved the peptide content, enhanced ABTS+ radical scavenging and ferrous ion chelating ability than non-ultrasound group. At the ultrasonic power of 450 W (20 min), peptides possessed significant anti-inflammatory activity, where the releasing of interleukin-6 (IL-6), and tumor necrosis factor-α (TNF-α) was all suppressed in lipopolysaccharide (LPS) induced RAW264.7 cells. After the analysis with LC-MS/MS, eight peptides with potential anti-inflammatory activities were selected by the PeptideRanker and molecular docking. In general, the ultrasound-assisted enzymatic hydrolysis was an effective strategy to extract the bioactive peptides from porcine bone, and the inflammatory regulation capacity of bone collagen sourced peptides was firstly demonstrated.

UPLC–QQQ–MS/MS-based widely targeted metabolomic analysis, antioxidant and α-glucosidase inhibitory activities of mulberry leaves processed by solid-state fermentation

Mulberry leaves contain various bioactive constituents and are widely used as traditional medicine and food in Asia. In this study, mulberry leaves were processed by solid-state fermentation (SSF) using a mixture microbial of Lactobacillus plantarum, Candida utilis, Trichoderma koningii, and Bacillus cereus. The effects of SSF on the metabolite profile, antioxidant activity, and α-glucosidase inhibitory activity (GIA) of mulberry leaves were investigated. UPLC–QQQ–MS/MS-based widely targeted metabolomic analysis showed the detection of 11 classes of metabolites. SSF drastically influenced the metabolites of mulberry leaves. A total of 441 differential metabolites were identified after SSF, with 165 metabolites remarkably up-regulated and 276 metabolites of mulberry leaves drastically down-regulated during fermentation. The main types of differential metabolites were phenolic acids and flavonoids. Furthermore, SSF significantly increased the levels of total phenolics and flavonoids, and enhanced the scavenging activities of DPPH radical and ABTS·+, reducing power, ferrous ion chelating ability, ferric reducing antioxidant power, and α-glucosidase inhibitory activity of mulberry leaves. In conclusion, our study revealed that SSF remarkably improved the phytochemical components of mulberry leaves, thereby contributing to the enhancement of antioxidant and α-glucosidase inhibitory activities.

Phytochemical analysis and in vitro anti-oxidant activity of Moringa oleifera leaves extract

The phytochemical contents such as, total phenolic, flavonoid and tannin content of ethanol extract of tender and matured leaves of Moringa oleifera were investigated. On the other hand, antioxidant activity test (total antioxidant activity, ABTS free radical scavenging activity, reducing power and ferrous ion chelating ability) were also studied. Total Phenolic content (203.80 ± 0.0014 and 105.00 ± 0.0045) mg/g gallic acid equivalent, total flavonoid content (26.02 ± 0.0031 and 18.20 ± 0.0025) mg/g quercetin equivalent and the total tannin content (12.90 ± 0.0021 and 10.50 ± 0.0012) mg/g of tannic acid equivalent were found in the ethanol extracts of tender and matured leaves of Moringa oleifera, respectively. The total antioxidant capacity of both leaves of the ethanol extracts were 217.43 ± 0.0025 mg/g and 210.65 ± 0.0019 mg/g respectively of ascorbic acid equivalent, respectively. Firstly, the IC50 value of tender and matured leaves of free radical scavenging activity test for ABTS (0.57 ± 0.0135 and 0.61 ± 0.0258) mg/mL were obtained using ascorbic acid as positive control (0.50 ± 0.0265 mg/mL). Secondly, reducing power ability was increased with higher concentration of all samples and standard. Finally, the IC50 value for ferrous ion chelating ability test was observed 5.10 ± 0.0121 and 9.20 ± 0.0212 mg/mL for ethanol extracts of tender and matured leaves respectively, whereas standard Na2EDTA was 4.0±0.0135 mg/mL. The result revealed that the ethanol extract of tender leaves showed more in-vitro antioxidant properties that of matured leaves. Bangladesh J. Sci. Ind. Res. 58(3), 179-186, 2023

Determination of polysaccharide and phenolic contents and antioxidant activity of the crude extract from mycelial biomass of strain Tropicoporus linteus NTH-PL3

Tropicoporus (synonym Phellinus) mushroom is one of the precious medicinal mushrooms and has been proven to play a significant role in supporting health. However, studies on the Tropicoporus mushroom have only been carried out in our country within the last ten years, so the scientific data on this mushroom source is not really rich. This study aimed to add research data on molecular identification of strain NTH-PL3 collected in nature and determination of bioactive compounds, as well as antioxidant activity of the total extract from mycelium of Tropicoporus. Results of rDNA ITS sequence analysis showed that strain NTH-PL3 belongs to Tropicoporus linteus species with the highest similarity in ITS sequence of 99.87%. The total yield of bioactive compounds extracted from the mycelium using 75% methanol was 29.75±3.84%. In the crude bioactive extract, total polysaccharide content was 23.72±1.34 mg glucose/g and 18.54±1.87 mg gallic acid/g for phenolic. EC50 values for 2,2-diphenyl-1-picrylhydrazyl (DPPH) free radical scavenging and ferrous ion chelating ability of total crude bioactive extract from mycelium of Tropicoporuswere 268.54±3.89 and 411.65±10.87 μg/ml, respectively.

Antioxidant Capacity of Lactic Acid Bacteria and Yeasts from Xinjiang Traditional Fermented Dairy Products

(1) Background: The objective of this study was to screen strains with antioxidant potential from lactic acid bacteria (LAB) and yeasts isolated from traditional Xinjiang fermentation products. (2) Methods: Twenty-three strains of LAB and twelve strains of yeast isolated from traditional fermented dairy products from different regions of Xinjiang were selected, and the strains with antioxidant ability were initially screened by measuring the hydroxyl radical scavenging, superoxide anion scavenging, DPPH radical scavenging, ABTS+ radical scavenging, anti-lipid peroxidation, and ferrous ion chelating abilities of their bacterial bodies, cell-free extracts, and fermentation broth. They were further screened by measuring their superoxide dismutase (SOD), glutathione peroxidase (GPX), and catalase (CAT) activities to identify strains with more powerful oxidative abilities. (3) Results: The results show that Lacticaseibacillus paracasei NM-12, Enterococcus faecium UM-12 and NM-11, and Pichia fermentans QY-4 had effective antioxidant enzyme activities. The SOD activity of these strains reached 4.846 ± 0.21 U/mL, 9.105 ± 0.428 U/mL, 8.724 ± 0.365 U/mL, and 6.518 ± 0.223 U/mL; the GPX activity reached 0.1396 ± 0.009 U/mL, 0.1123 ± 0.006 U/mL, 0.014 ± 0.007 U/m, and 0.0919 ± 0.006 U/mL; and the CAT activity reached 19.934 ± 3.072 U/mL, 3.749 ± 0.926 U/mL, 92.095 ± 1.017 U/mL, and 97.289 ± 0.535 U/mL, respectively (p < 0.05). (4) Conclusions: Lacticaseibacillus paracasei (NM-11), Enterococcus faecium (UM-12, NM-11), and Pichia fermentans (QY-4), isolated from traditional fermented dairy products, are probiotics with high antioxidant activity and potential applications in the food and fermentation industries.

Impact of Nitrite Supplementation on Bioactive Peptides during Sausage Processing.

The goal of this investigation was to examine the impact of nitrite supplementation on the concentration, antioxidant properties, and species of antioxidant peptides in fermented sausages. The polypeptide concentration in nitrite-supplemented sausages was markedly elevated during sausage processing compared to the blank control (p < 0.05). Moreover, nitrite supplementation in fermented sausages markedly enhanced the DPPH, as well as the ABTS, hydroxyl radical, and superoxide anion free radical scavenging abilities (FRSA) of polypeptides (p < 0.05). The ferrous ion chelating ability was also significantly enhanced (p < 0.05). Based on the liquid chromatograph-mass spectrometer (LC-MS) analysis of the sausage, LPGGGHGDL, TKYRVP, FLKMN, SAGNPN, GLAGA, LPGGGT, DLEE, GKFNV, GLAGA, AEEEYPDL, HCNKKYRSEM, TSNRYHSYPWG, and other polypeptides exhibited antioxidant properties. Moreover, the number of species of antioxidant polypeptides in the nitrite-supplemented sausage was greater in comparison to the controls. Based on this evidence, it may be concluded that nitrite supplementation positively modulated antioxidant polypeptide formation in fermented sausages, thereby providing strong evidence that nitrite supplementation significantly enhances sausage quality.

Alkylsuccinylated oxidized cellulose-based amphiphiles as a novel multi-purpose ingredient for stabilizing O/W emulsions

A novel type of emulsifiers (STOC- SAC0, SAC8 & SAC12) were synthesized from nature-abundant cellulose by a two-step process: preparartion of soluble cellulose by TEMPO-mediated oxidation of cellulosic nanocrystal and fractionation (STOC), and introduction of hydrophobic moiety by alkyl (C0, C8 & C12)succinylation of resulting soluble polysaccharides. The synthetic products were structurally verified by Fourier Transform Infrared (FT-IR), Nuclear Magnetic Resonance (NMR) and Gel Permeation Chromatography (GPC). The surface-active property and functionality of the new ingredients were characterized by determinations of contact angle, ABTS radical scavenging and Ferrous chelating ability, and their performance as new ingredient; which demonstrated that alkylsuccinylated soluble TEMPO-oxidized celluloses (STOC-SAC x ) have unique multi-purpose functionalities: emulsifying, stabilizing and antioxidant property. STOC-SAC12 displayed the best surface activity with the lowest contact angle (18° on a hydrophobic surface basis) and the highest antioxidant properties (compared to succinylated cellulose (C-SAC0) the ABTS radical scavenging and Fe 2+ chelating property of STOC-SAC12 are significantly higher by 10-fold and 4.5-fold, respectively); accordingly STOC-SAC12 also resulted in the most stable homogeneous fish oil-in-water nanoemulsion with a mean droplet size of 200 nm, polydispersity index of 0.18 and ζ-potential up to −90 mV; evidenced by scanning electron microscopy (SEM) and confocal laser scanning microscopy (CLFM) and dynamic light scattering analyses. In short this work reported a industry-feasible and fully scalable approach to transform abundant renewable plant cellulose into novel ingredients with unique fucntionalities which could find potential application in delivery of oxidation-prone bioactives through complicated emulsion systems. • Alkyl (C 0 , C 8 , C 12 )succinylation endowed cellulose/Soluble TEMPO-Mediated Oxidized Celluloses (STOC) with various surface-active properties. • Successful alkylsuccinylation of cellulose/STOC were confirmed by FTIR, NMR (GPC analysis for STOC). • STOC-SAC12 demonstrated excellent multi-purpose functionalities as emulsifier, stabilizer and antioxidant. • Compared to C-SAC0 the ABTS radical scavenging and Fe 2+ chelating property of STOC-SAC12 are 10-fold and 4.5-fold higher.

Evaluation of antimicrobial, antioxidant and cytotoxicity potential of R-phycoerythrin extracted from Gracilaria corticata seaweed

In the present study, phycoerythrin pigment protein was extracted and purified from Gracilaria corticata (marine macroalga). The concentration of phycoerythrin (PE) obtained from G. corticata was 0.15 ​mg/ml (fresh weight). In this study, phycoerythrin expressed less antimicrobial activity against pathogens but found effective in total antioxidant activity (264.90 ​± ​10.20 ​μg/ml), DPPH scavenging effect (22.91 ​± ​1.90%) and ferrous ion chelating ability (26.06 ​± ​1.60%). Further, the cytotoxicity assay of PE using colon cancer cells such as SW620 and HCT-116 was tested. Different concentrations (2, 4, 8, 16, 32 ​μl) of phycoerythrin was tested in MTT assay after 24 ​h and 48 ​h incubation. The MTT assay concludes that increasing concentration of phycoerythrin (4.8 ​μg) decreases the cell viability to 42% after 48 ​h in SW 620 ​cell line. Whereas in the HCT 116 ​cell line the increasing concentration of phycoerythrin induces the cell growth on 24 ​h but later drastically reduced growth of cell line (39%) was observed after 48 ​h time in 4.8 ​μg of PE. From this preliminary study, the phycoerythrin pigment extracted from Gracilaria corticata proved to be a potential molecule of interest for cancer studies and diagnosis.

Phytochemical Screening and Bioactive Properties of Juglans regia L. Pollen.

Pollen is one of the major by-products of the walnut tree, yet it is poorly investigated. Thus, the aim of this study was to investigate the total phenolics, flavonoids, antioxidant, anticancer potential, and polyphenol profile of pollen obtained from male Juglans regia flowers. A total of 24 phenolic compounds were identified in Juglans regia pollen and all of them were reported for the first time for this raw material. The content of polyphenols was 408.03 mg/100 g dry weight (dw) and the most abundant components were quercetin 3-O-sophoroside and 4′,5,7-trihydroxy-3,6-dimethoxyflavone-7-O-beta-D-glucoside. The concentration of these compounds, as well as the total content of polyphenols and flavonoids, strongly determined the antioxidant and cytotoxic activity of Juglans regia pollen. Antioxidant action using the ABTS and CUPRAC methods had the values of 3.35 and 0.32 mmol TE/g dw, respectively. In turn, in the tests of chelating ability of ferrous ion, O2•− and OH− radical scavenging activity, of which the results were expressed as IC50, the values were equal to 335.01, 459.31, and 92.89 µg/mL, respectively. Among the six cancer cell lines, the strongest effect was demonstrated for Caco-2 (140.65 µg/mL) and MCF-7 (140.98 µg/mL) cells. The results provide valuable and previously unpublished data on the polyphenol composition and biological potential of Juglans regia pollen.

Determination of Chemical Compounds and Investigation of Biological Properties of Matricaria chamomilla Essential Oils, Honey, and Their Mixture.

This exploratory investigation aimed to determine the chemical composition and evaluate some biological properties, such as antioxidant, anti-inflammatory, antidiabetic, and antimicrobial activities, of Matricaria chamomilla L. essential oils (EOs). EOs of M. chamomilla were obtained by hydrodistillation and phytochemical screening was performed by gas chromatography–mass spectrophotometry (GC-MS). The antimicrobial activities were tested against different pathogenic strains of microorganisms by using disc diffusion assay, the minimum inhibitory concentration (MIC), and minimum bactericidal concentration (MBC) methods. The antidiabetic activity was performed in vitro using the enzyme inhibition test. The antioxidant activity of EOs was tested using the free radical scavenging ability (DPPH method), ferrous ion chelating (FIC) ability, and β-carotene bleaching assay. The anti-inflammatory effects were tested in vivo using the carrageenan-induced paw edema method and in vitro using the inhibition of the lipoxygenase test. The analysis of the phytochemical composition by GC-MS revealed that camphor (16.42%) was the major compound of EOs, followed by 3-carene (9.95%), β-myrcene (8.01%), and chamazulene (6.54%). MCEO, honey, and their mixture exhibited antioxidant activity against the DPPH assay (IC50 ranging from 533.89 ± 15.05 µg/mL to 1945.38 ± 12.71 µg/mL). The mixture exhibited the best radical scavenging activity, with an IC50 of 533.89 ± 15.05 µg/mL. As antidiabetic effect, EO presented the best values against α-glucosidase (265.57 ± 0.03 μg/mL) and α-amylase (121.44 ± 0.05 μg/mL). The EOs and honey mixture at a dose of 100 mg/kg exhibited a high anti-inflammatory effect, with 63.75% edema inhibition after 3 h. The impact of EOs on the studied species showed an excellent antimicrobial (Staphylococcus aureus ATCC 29213 (22.97 ± 0.16 mm)), antifungal (Aspergillus niger (18.13 ± 0.18 mm)) and anti-yeast (Candida albicans (21.07 ± 0.24 mm) effect against all the tested strains. The results obtained indicate that the EOs of M. chamomilla could be a potential drug target against diabetes, inflammation and microbial infections; however, further investigations to assess their bioactive molecules individually and in combination are greatly required.

Antioxidant potential of extracts of Chromochloris zofingiensis cultivated in pilot-scale outdoor tubular photobioreactors under nitrogen limitation

Chromochloris zofingiensis is known to be able to produce large amounts of astaxanthin and also to coproduce other molecules with antioxidant properties. Outdoor cultivation is the cheapest way for large-scale production; however, the unstable weather conditions can hinder the productivity of the biomass and the target product. The final biomass (0.92 g·L−1) and total carotenoids (0.55 mg·g−1) concentration achieved in outdoor cultivation (i.e., during autumn in Porto, Portugal) had no statistically significant difference compared to control cultivation (i.e., constant temperature, 18 °C, and light intensity, 4000 lx) (1.36 g·L−1 and 0.56 mg·g−1, respectively), however the biomass productivity was about threefold lower. Regarding the antioxidant potential, methanolic extracts from outdoor cultivation presented one of the highest values for radical scavenging ability (44.2 %) and ferrous-ion chelating ability (59.1 %), similarly to the results obtained by ethanolic extracts from indoor cultivation under nitrogen limitation. Highest total antioxidant capacities were observed in ethanolic extracts varying from 120.0 to 185.2 mg GAE·g−1.

Development of instant vegetarian cream soup from tempeh powder to increase antioxidant capacities

Tempeh is an Indonesian traditional soyfood made by Rhizopus spp. fermentation. Tempeh has been well known as a vegetarian-friendly food and has been processed into various derived food products. This study aimed to develop an instant vegetarian cream soup from tempeh powder. The addition of tempeh powder was expected to increase the product’s antioxidant activity without compromising its physicochemical properties as an instant product. The five different formulations of cream soups containing 0–30% tempeh powder were analysed for their physicochemical properties (dissolving time, density, viscosity, colour, pH), antioxidant capacity (total phenolic content, total flavonoid content, DPPH radical scavenging activity, reducing power, and ferrous ion chelating ability), and hedonic test. Soup cream made with more tempeh power had a higher dissolving time, but lower viscosity, lightness value, and pH value. However, their antioxidant activities also increased with the increase of tempeh powder added. From the hedonic analysis, the formulation with 15% tempeh powder showed the highest hedonic rate and therefore, was chosen as the best formulation. In conclusion, the addition of tempeh powder did not only give a better consumer acceptance but also higher antioxidant activities.

Novel antioxidant peptides identified in millet bran glutelin-2 hydrolysates: Purification, in silico characterization and security prediction, and stability profiles under different food processing conditions

Based on a model generated from response surface methodology, the optimum hydrolysis conditions of millet bran glutelin-2 (MBG-2) were obtained with a concentration of Papain of 8.17 mg/g MBG-2, at pH 7.83 and 51.6 °C for 5.9 h. Through Sephadex G-15 gel chromatography, RP-HPLC and UPLC-ESI-MS/MS analysis, three novel antioxidant peptides (CFMTY, CTGTPYC and RGLLLPSMSNAP) were identified in MBG-2H. The antioxidant activity, stability profiles of these peptides against different pH values, thermal treatments, treatment of glucose and NaCl, and simulated gastrointestinal digestion were studied. Moreover, the physicochemical property, potential toxicity and allergenicity were predicted in silico. Results showed that CFMTY, CTGTPYC and RGLLLPSMSNAP all had no potential toxicity and allergenicity, and showed high scavenging activity on ABTS+ (IC50: 80.85, 87.78 and 214.17 μmol/L), ·OH and superoxide radical. Both CFMTY and CTGTPYC showed excellent ferrous chelating ability (98.97%–99.24%, at 100 μg/mL) which was close to Glutathione. Moreover, these peptides were relatively stable against different pH values (2.0–8.0), pasteurization conditions and treatments of glucose and NaCl (<4 mg/mL). These peptides except RGLLLPSMSNAP were resistant to the gastrointestinal digestion. Therefore, the antioxidant peptides derived from MBG-2H have potential to be added into foods for preservation.

Investigation on a Novel Mushroom, Russula pseudocyanoxantha: Chemical Composition and Antioxidant Potency

Mushrooms are traditionally being appreciated for health promotion and nowadays considered as an effective source of dietary antioxidants. Despite that, research on them is scarce and thus many species still remain totally unexplored. In this regard, we have recently introduced a novel bioactive macrofungus, Russula pseudocyanoxantha, collected from lateritic areas of West Bengal, India. Local tribes consider the specimen as a gourmet cuisine inspiring us for further investigation to predict downstream application. Thus, the present study was carried out with an aim to explore functional secondary metabolites of the taxon influencing antioxidant activity. For that, a hydro-ethanol extract was isolated that was found to be enriched in phenolic compounds (p-coumaric acid&lt; cinnamic acid&lt; pyrogallol) followed by ascorbic acid and carotenoids. Subsequently, significant in vitro radical (hydroxyl, DPPH and ABTS) scavenging effect, ferrous ion chelating ability and reducing power were recorded where EC50 values ranged from 15 to 2674 μg/ml. Thus, incorporation of the novel myco-food into daily diet could provide health benefits to consumers suggesting probable use in nutraceutical, cosmetic and pharmaceutical industries.

Antioxidant, Anti-Inflammatory Activities, and Neuroprotective Behaviors of Phyllanthus emblica L. Fruit Extracts

Phyllanthus emblica L. is traditionally used as both medicine and food in Taiwan. In this study, we evaluated the antioxidant, anti-inflammatory, and neuroprotection bioactivities of P. emblica fruit. P. emblica fruit extracts had a high content of total phenol and flavonoids, and chlorogenic acids. For antioxidant capacity, 95% ethanol-extracted P. emblica had the best DPPH radical scavenging activity, ferrous ion chelating ability, and reducing power as compared with hot water, 50% ethanol, and commercial extracts, and showed the highest reducing power and lipid peroxidation inhibition. The present results have demonstrated that the P. emblica extracts can protect the oxidative degradation of lipids by inhibiting FeCl3-ascorbate-mediated lipid peroxidation. For anti-inflammatory activity, P. emblica fruit extracts showed dose-dependent inhibition of nitric oxide in lipopolysaccharide-stimulated RAW264.7 cells and significantly high COX-2 inhibition. For neuroprotection bioactivity, P. emblica extracts had higher percentages of pheochromocytoma cell protection than commercial extracts. Hot water and ethanol extracts showed higher percentages of PC12 cell protection than commercial extracts. P. emblica hydroalcoholic extracts had a neuroprotective effect against oxidative damage, which could be due to their antioxidant and anti-inflammatory activity. P. emblica extracts could be used in daily health beverages, foods, and cosmetic products.

Effect of oxidative modification on physicochemical and functional properties of soybean polysaccharides

Oxidized soybean polysaccharides (OSSPS-1 and OSSPS-2) were prepared. Their structure was characterized, and their physicochemical and functional properties were evaluated. Structural analysis showed that the hydroxyl groups of soybean polysaccharides (SSPS) were oxidized to carboxyl groups. The molecular weight decreased from 1.5 × 105 Da (SSPS) to 7.2 × 104 Da (OSSPS-1) and 7.0 × 104 Da (OSSPS-2), respectively. The carboxyl content of SSPS, OSSPS-1 and OSSPS-2 was 1.79%, 6.08% and 9.45%, respectively. Uronic acid content of SSPS, OSSPS-1 and OSSPS-2 was 4.15%, 7.39% and 10.29%, respectively. Compared with SSPS, OSSPS-1 and OSSPS-2 showed decreased emulsifying property. Oxidative modification greatly reduced the viscosity of SSPS and changed their viscoelasticity. Whereas, oxidative modification improved a series of viscosity-related functional properties of SSPS, such as fat binding capacity, bile acid binding capacity, hypoglycemic effect. The antioxidant and antibacterial activities of SSPS were enhanced after oxidative modification. OSSPS-1 possessed higher DPPH scavenging ability, ferrous iron chelating ability and reducing power than OSSPS-2, but OSSPS-2 showed better antibacterial activities than OSSPS-1. The result revealed that oxidative modification had a significant effect on the structure of SSPS, which further affected the functional properties and biological activities of SSPS.

Storage quality and antioxidant properties of yogurt fortified with polyphenol extract from nutmeg, black pepper, and white pepper

BackgroundThe consumption of antioxidant-rich foods can lower the risk of chronic diseases. In the present work, plain yogurt (control) and three kinds of herbal yogurts fortified with a polyphenol extract from nutmeg, black pepper, and white pepper were prepared. Post-acidification, proteolysis, total phenolic content (TPC), and antioxidant activity of yogurt samples were studied over 21 days. Additionally, all yogurt samples were subjected to sensory evaluations on the first day of storage. ResultsHigher production (p < 0.05) of lactic acids was observed in all herbal yogurts than in plain yogurt over 21 days of storage. Black pepper and nutmeg enhanced (p < 0.05) the proteolytic activity of yogurt as compared to control, with the maximum values at 21 days. All three herbal yogurts showed the highest TPC (48–55 µg GAE/ml) at day 14 of storage. The radical scavenging activity of yogurt was positively affected (p < 0.05) by the presence of the three kinds of herbal extracts (72–83%; day 0), with the highest values observed in nutmeg yogurt. Ferric reducing antioxidant potential (FRAP) value of nutmeg yogurt was the highest (p < 0.05) among the other samples at day 7 of storage. The ferrous ion chelating (FIC) ability of all the three herbal yogurts ranged from 80% to 83% during 2 weeks. The highest overall preference scores among the three kinds of herbal yogurts were recorded for black pepper yogurt. ConclusionsPolyphenol compounds derived from nutmeg, black pepper, and white pepper extracts could enrich yogurt with antioxidant properties, with nutmeg yogurt showing the best effect.How to cite: Shori AB. Storage quality and antioxidant properties of yogurt fortified with polyphenol extract from nutmeg, black pepper, and white pepper. Electron J Biotechnol 2022;57. https://doi.org/10.1016/j.ejbt.2022.03.003

Evaluation of antioxidant and antibacterial activities of fish protein hydrolysate produced from Malaysian fish sausage (Keropok Lekor) by-products by indigenous Lactobacillus casei fermentation

Malaysian fish sausage, Keropok Lekor (KL), is a popular fish snack in Malaysia. The fish by-products (FBPs) from KL processing comprise a significant quantity of proteins with high nutritional value. However, in Malaysia, such FBPs are either disposed of into waterways, which may cause environmental pollution, or are processed into products of low economic value, such as fertiliser and animal feed. To maximise the potential of FBPs, a microbial fermentation approach can be used to convert FBPs into bioactive fish protein hydrolysate (FPH). Bioactive FPH has higher economic value due to its potential as a bio-ingredient in the nutraceutical and functional food industries. This study aimed to evaluate antioxidant and antibacterial activities of FPHs from FBPs of KL processing produced by four indigenous Lactobacillus casei strains (LC216, LC217, LC219, and LC220). The relationship between the level and composition of free amino acids during fermentation and the antioxidant and antibacterial activities of the produced FPH was evaluated. The results showed that the FPHs produced using the four L. casei strains had higher 2,2-Diphenyl-1-picrylhydrazyl (DPPH) radical scavenging activities (82.8–88.4%) than that of the unfermented FBPs (78.9%). The obtained half-maximal effective concentrations (EC50) of the FPHs were also significantly lower (p < 0.05) than those of the unfermented FBPs. The ferrous chelating ability of the FPHs produced using strain LC217 improved by 68.43% compared to that of the unfermented FBPs. Furthermore, compared to the unfermented FBPs, the FPHs produced using strains LC216 and LC217 had a significantly higher (p < 0.05) maximum growth inhibition against Listeria monocytogenes, Salmonella typhimurium, Escherichia coli and Listeria innocua. Moreover, there was a positive relationship between the degree of hydrolysis and the bioactivities. A strong positive correlation also existed between the level of antioxidant amino acids content and antioxidant activity. Overall, the L. casei fermentative production of bioactive FPHs from the FBPs from KL processing represents an effective, environmentally sustainable and economical strategy for producing bioactive bioingredients, which can be used in functional food production and food preservation.