Changes In Antioxidant Properties Research Articles

Changes in antioxidant properties and structure of Pediococcus acidilactici's polysaccharide: In vitro simulated digestion

The objective of this study was to investigate the dynamic changes in the physicochemical and antioxidant properties of polysaccharides derived from Pediococcus acidilactici (S1-CEPS) through in vitro analysis. A simulated fermentation process resulted in structural modifications of S1-CEPS, accompanied by an increase in its antioxidant activity. Significant enhancements were observed in the content of reducing sugars (p < 0.05), primarily galactose and glucose being released. Moreover, there was a strengthening effect on functional groups such as –OH, –COOH, –CO, and –OSO–O-. Additionally, gut microbes degraded and utilized S1-CEPS to produce short-chain fatty acids (SCFAs), including acetic acid, propionic acid, and n-butyric acid. Furthermore, S1-CEPS exhibited significant modulatory effects on microbial composition by increasing the relative abundances of Proteobacteria and Bacteroidetes while decreasing those of Escherichia-Shigella, Klebsiella, and Fusobacterium. Based on these findings, it is suggested that S1-CEPS derived from Pediococcus acidilactici holds potential as a functional food for promoting health improvement and disease prevention.

Evaluation of Dry Ice for Short-Term Storage and Transportation of Frozen Boar Semen.

To address the safety problems posed by the transportation of boar semen using LN, this study was conducted on the short-term storage of frozen boar semen in dry ice (-79 °C). Boar semen frozen in LN was transferred to dry ice, kept for 1 day, 3 days, 5 days, 7 days, or 8 days, and then moved back to LN. The quality of frozen semen stored in LN or dry ice was determined to evaluate the feasibility of short-distance transportation with dry ice. The results showed that 60 °C for 8 s was the best condition for thawing frozen semen stored in dry ice. No significant differences in spermatozoa motility, plasma membrane integrity, or acrosome integrity were observed in semen after short-term storage in dry ice compared to LN (p > 0.05). There were no significant changes in antioxidant properties between storage groups either (p > 0.05). In conclusion, dry ice could be used as a cold source for the short-term transportation of frozen boar semen for at least 7 days, without affecting sperm motility, morphological integrity, or antioxidant indices.

Changes in antioxidant properties of pepper leaves (Capsicum annuum L.) upon UV radiation

Bell pepper (Capsicum annuum) is one of the most popular vegetables consumed worldwide. The leaves of pepper are rich in phenolics, including phenolic acids and flavonoids. These compounds are well known for their ultraviolet (UV) absorbing and antioxidant properties. While the change of the phenolic pattern is an intensive research subject, it is not yet well-known in pepper leaves, particularly in outdoor conditions. In this experiment, we examined the effect of UV radiation on the leaves of outdoor grown peppers, focusing on the UV-absorbing properties and antioxidant capacities. Three different total antioxidant capacity (TAC) measurements have been compared: (I) Folin-Ciocalteu Reactivity (FC), (II) Ferric Reducing Antioxidant Power (FRAP) and (III) Trolox Equivalent Antioxidant Capacity (TEAC). Moreover, non-enzymatic hydrogen peroxide scavenging antioxidant capacity was measured. Significant increase was detected only in FRAP, suggesting an elevation exclusively in the level of phenolic acids in case of UV exposed outdoor grown pepper leaves.

Enhancing grain yield, oil content, fatty acid composition and changes in antioxidant properties of camelina using Wi-Fi radiation

Enhancing grain yield, oil content, fatty acid composition and changes in antioxidant properties of camelina using Wi-Fi radiation

Changes of antioxidant properties of Indonesian honey under heat treatment

Post-harvest heating on honey is crucial for moisture reduction, microbial inhibition, and crystallization prevention, yet it can diminish bioactive compounds such as antioxidants. This study aims to investigate the impact of heating on the antioxidant properties of Indonesian honey, encompassing three Apini and three Meliponini honey types. While all samples exhibited changes in antioxidant properties post-heating, Apini honey displayed a more consistent pattern compared to Meliponini honey. The DPPH assay, total phenolic content, and total flavonoid content consistently indicated a decline in antioxidants at lower temperatures and short durations of heating, followed by an increase at high temperatures and longer duration, suggesting a compensation mechanism through the generation of new antioxidants via Maillard’s reaction. However, the ferric reducing power assay revealed a consistent decrease in antioxidants post-heating for Apini honey, indicating damage to natural antioxidants without compensation, whereas Meliponini honey displayed irregular dynamics, suggesting both damage and formation of antioxidants. The Apini honey showed the best antioxidant properties at high temperatures (100°C), whereas Meliponini honey showed an optimum at low temperature (50°C) for extended durations or medium temperature (75°C) for shorter durations.

Binding behavior and antioxidant study of spice extract piperine with respect to meat myoglobin.

It has been reported in many studies that piperine (PIP) has multiple activity properties, the most prominent of which is antioxidant activity. This work reports the binding behavior and antioxidant activity of the spice extract piperine towards myoglobin (Mb) using spectroscopic and fluorescence spectra analysis, and computational approaches. Antioxidant activity studies have shown that the antioxidant effect of the Mb-PIP complex system depends on the concentration of PIP added. An appropriate concentration of PIP can successfully prevent the release of free iron from Mb. The fluorescence results indicated that the binding of PIP to Mb was via static quenching. After binding to PIP, the α-helix content of Mb decreased by about 5%. Synchronous fluorescence results indicate that PIP is closer to Trp, and MD simulations also demonstrate that PIP enters the hydrophobic cavity of Mb and binds stably. This explains the structural changes in proteins that lead to changes in antioxidant properties. The results of this study provide a reference for the quality control of additives of plant origin in the processing and storage of meat and meat products.

Effect of Alcalase Modification of Yellow Lupin (Lupinus luteus L.) Protein Isolate on Some Functional Properties and Antioxidant Activity.

Protein isolate obtained from sweet yellow lupin (Lupinus luteus L.) and its Alcalase hydrolysates were examined for their functional and antioxidant properties in relation to surface hydrophobicity of proteins and peptides and molecular weight distribution. Enzymatic hydrolysis improved the foaming characteristics of lupin proteins, while the emulsifying properties deteriorated. It means that good foaming properties of preparations are determined by the presence of low-molecular δ conglutin and small subunits of γ conglutins. In turn, larger proteins such as α and β conglutin are responsible for maintaining good emulsifying properties. The measured surface hydrophobicity was consistent with the results of emulsifying properties. It has also been shown that the scope of changes in antioxidant properties due to hydrolysis, measured by DPPH method and as reducing power, is more pronounced than with the use of ABTS and FRAP methods.

Antioxidative properties of bayberry tannins with different mean degrees of polymerization: Controlled degradation based on hydroxyl radicals

The antioxidant properties of condensed tannins (CTs) are closely related to the mean degree of polymerization (mDP), and CTs with low mDP show stronger antioxidant effects. Therefore, obtaining CTs with a low mDP are very meaningful in improving their antioxidant properties and utilization. In this study, hydroxyl radicals generated by the decomposition of hydrogen peroxide under UV irradiation were used to degrade bayberry tannins in a clean and controllable manner. Taking the formaldehyde reactivity as an index to control the mDP of the degradation product, the changes in antioxidant properties of bayberry tannins with different mDP were studied by the method of 1,1-diphenyl-2-trinitrophenylhydrazine (DPPH), and 2,2-azido-di(3-ethyl-benzothiazole-6-sulfonic acid)diammonium salt (ABTS). Matrix-assisted laser desorption ionization time-of-flight mass spectrometry (MALDI-TOF-MS), gel permeation chromatography (GPC), carbon nuclear magnetic resonance (13C NMR), and reversed-phase HPLC-ESI-MS were used to characterize the mDP, molecular weight (Mw), and chemical structure of the degradation products of bayberry tannins in different degradation stages. Results showed that hydroxyl radicals could cause significant degradation of bayberry tannins, and the controllable degradation of bayberry tannins could be achieved with the formaldehyde reactivity as an index. At the degradation times of 0, 2, 4, 6, and 8 h, the mDP (Mw) of the degradation products were as follows: 5.22 (2457), 4.36 (1895), 3.36 (1534), 2.87 (1153), and 1.78 (813), respectively. The antioxidant activity of the degraded product increased with the decrease in the mDP, and the degraded products had the largest formaldehyde reactivity and the best oxidation resistance when degraded for 6 h. This study provided a new method to achieve clean and controllable degradation of tannins and supported those tannins with low mDP could provide higher antioxidant activity.

Investigation of Changes of Antioxidant Properties of Coffee through Fermentation by Using Saccharomyces Cerevisiae and Bacillus Subtilis

The study was carried out to investigate the changes of antioxidant properties and quality of green coffee beans fermented by using Bacillus subtilis and Saccharomyces cerevisiae as starter cultures in sugarcane and banana juice at different times fermentation. The fermentations were conducted with different juice concentrations for different fermentation times 24, 48, and 72 hours at room temperature. Antioxidant properties were determined by Folin-Ciocalteu reagent for the determination of total phenolic content, DPPH assay for the determination of antioxidant capacity, and colorimetric method used for determination of total flavonoid content. As a result, coffee fermentation at 10oBrix, 107 cells/mL for each type of microbe, and the time (48 hours) had a positive effect on antioxidant properties. However, there was not a significant difference in terms of antioxidant properties between fermented and original coffee beans at optimal conditions. Therefore, antioxidant properties were dramatically reduced during the early stages of fermentation, but it was shown to be able to overcome it through this study. This study is a premise to applying microbial products through fermentation to create a coffee with high antioxidant activity compared to conventional coffee products.

Impact of Bioactive Compounds of Plant Leaf Powders in White Chocolate Production: Changes in Antioxidant Properties during the Technological Processes.

Bioactive compounds present in the powdered leaves of matcha green tea (Camellia sinensis L.) (MGTP) and moringa (Moringa oleifera) (MOLP) seem to be related to health benefits due to their antioxidant properties. The growing accessibility of these powders has led to their being more widely used in food production. The aim of this study was to evaluate the total phenolic content (TPC) and antioxidant capacity (AC) of white chocolate (WCh) supplemented with MGTP and MOLP. AC was determined by 2,2-diphenyl-1-picrylhydrazyl (DPPH), 2,2′-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS), cupric ion-reducing antioxidant capacity (CUPRAC), and ferric-reducing antioxidant power (FRAP) assays, whereas TPC was determined by the Folin–Ciocalteu (FC) method. Both additives were incorporated at four levels (1, 2, 3 and 4%) in two chocolate processing steps (conching and tempering). Additionally, the amounts of phenolic acids, tocopherols, and carotenoids in WCh samples enriched by MGTP and MOLP were determined to explain their influence on AC. The results showed that the chocolates supplemented with MGTP were characterized by higher antioxidant properties than those with MOLP. In turn, MOLP significantly increased the content of lipophilic antioxidants in chocolates, tocopherols and carotenoids, which also exhibit pro-health effects. Furthermore, the incorporation of these additives during the tempering process was more relevant to the improvement of the antioxidant properties of WCh.

Changes in Antioxidant Properties and Phenolics in Sweet Potatoes (Ipomoea batatas L.) Due to Heat Treatments.

Processing is one of the most crucial factors affecting polyphenol content in foods. Therefore, the study is aimed at the evaluation of heat treatment effects (microwaving, steaming, baking, and boiling) on the content of chlorogenic acids, total polyphenols, and antioxidant activity of three varieties of sweet potato with different flesh colors (Beauregard—orange-fleshed, O’Henry—white-fleshed, 414-purple—purple-fleshed). According to high performance liquid chromatography analysis, chlorogenic acid was the predominant chlorogenic acid in sweet potatoes. Obtained results also suggested the purple-fleshed variety (414-purple) had significantly (p < 0.05) higher total polyphenol content and thus the highest antioxidant activity. Heat treatment positively influenced the chlorogenic acid content, total polyphenols, and antioxidant activity of sweet potatoes. Among the used methods, steaming had the greatest effect on the chlorogenic acids and total polyphenols, while microwaved samples showed the highest antioxidant activity (DPPH). The content of chlorogenic acids and total polyphenols decreased in the order of steaming > baking > microwaving > boiling > raw. However, the individual varieties differed not only in the flesh color but also in the reaction to the used heat treatment methods. Spearman’s correlation coefficient showed a strong correlation between chlorogenic acid and antioxidant activity.

FERMENTED FOOD PRODUCTS USING SEA BUCKTHORN FRUIT. OVERVIEW

Herbal raw materials are a unique source of biologically active substances that are of particular value in the treatment of various diseases. Sea buckthorn is one of the most famous and widespread medicinal plants, widely grown in the United States, Europe, Asia, the Russian Federation and the Republic of Belarus. Information on the phytochemical composition of fruits is quite fully covered in the scientific literature. Sea buckthorn fruits are rich in essential nutrients and biologically active substances, but remain less in demand. Thus, it is important to study and implement new ways of processing sea buckthorn fruits that can contribute to the development of new functional foods and attract the attention of consumers to these products. This review summarizes studies on the development of food products using sea buckthorn fruits and lactic acid bacterial cultures. Particular attention is paid to the process of malolactic fermentation and its influence on the content and profile of organic acids and polyphenols in the juice of sea buckthorn fruits, it is shown what changes in antioxidant properties and organoleptic characteristics occur. The role of sea buckthorn fruits and their components in the development of new probiotic dairy and non-dairy products is considered.

Changes in Antioxidant Properties and Amounts of Bioactive Compounds during Simulated In Vitro Digestion of Wheat Bread Enriched with Plant Extracts.

Cereal preparation can be an excellent source of substances with proven health-promoting properties. Unfortunately, some types of bread, such as white flour bread, are devoid of many valuable nutrients. Therefore, it is necessary to look for ways to increase its density and nutritional value. The aim of the study was to investigate the effect of stabilized plant extracts on the quality of bread, its antioxidant activity and polyphenol content, and to evaluate the stability of bioactive compounds and antioxidant activity during in vitro digestion. The research material was the wheat bread baked with spray dried microcapsules of hawthorn bark, soybeans and onion husks in maltodextrin or inulin carriers. The addition of plant extracts resulted in the presence of phenolic compounds in the wheat bread, and its antioxidant activity significantly increased. There was no significant difference in antioxidant activity between breads containing microcapsules with different carriers. During in vitro digestion, procyanidins and isoflavones in bread were more resistant to the digestive processes than other compounds. The antioxidant activity during simulated digestion was the highest at the stage of gastric digestion, and its value depended on the extract used and the analytical method applied.

Utilization of Oenococcus oeni strains to ferment grape juice: Metabolic activities and beneficial health potential

This study aimed to investigate the behavior of Oenococcus oeni MS9 and MS46 strains in sterile grape juice (SGJ, pH 4.0) incubated at 30 °C, in terms of growth and glucose, organic acids and total phenolic compounds utilization. In addition, their antimicrobial activity and the changes in antioxidant properties of fermented juice with selected strain were evaluated. Both strains grew without lag period by ~1.40 log CFU/mL at 12 days with maximum growth rates of about 0.019 h−1. After this time the MS9 and MS46 strains counts declined by 0.6 log units and remained unchanged respectively. O. oeni MS46 was evaluated in SGJ for low inoculum size (~104 CFU/mL). In this condition it also grew without lag period by 3.11 ± 0.01 log CFU/mL with a μmax of 0.05 h−1. Glucose and L-malic and citric acids were simultaneously utilized but at different rates and extents, yielding mainly lactic acid with concomitant pH reduction. Acetic acid ranged between 11 and 19 mmol/L. Total phenolic compounds significantly decreased in fermented SGJ with strain MS9 but not MS46. In this last condition, the antioxidant activity increased by 21%. In addition, both O. oeni strains showed antibacterial properties against Escherichia coli 700, Salmonella Typhimurium and Listeria monocytogenes. O. oeni strains, especially MS46, with the ability to growth in SGJ, high malolactic potential and adequate sugars and organic acids profiles from the sensorial viewpoint may be used to ferment grape juice with safer and healthier properties than fresh juice.

Effects of tetrahydro-curcumin on the formation of β-carboline heterocyclic amines in dry-heated soy protein isolate in the presence of glucose

β-carboline heterocyclic amines (β-CHAs) are substances widely present in food products, and are considered to have synergistic teratogenicity. In this study's experiments, the dry-heated glucose (Glc)-containing soy protein isolate (SPI) was used as a model to examine the effects of tetrahydro-curcumin (THC) on the formation of β-CHAs. The structural characteristics of the protein, ninhydrin-reactive amino nitrogen (NRAN), changes in antioxidant properties, and so on, before and after heat treatments were studied at the same time. The results showed that 1 g/100 g Glc in SPI could inhibit the formation of 1-methyl-9H-pyrido [3,4-b]indole (Harman), while promoting the formation of 9H-pyrido [3,4-b]indole (Norharman). THC could inhibit Norharman formation during the dry heat processes of Glc-containing SPI when the addition content was 1 g/100 g (P < 0.05), and the inhibitory effects increased with the increases in the content of THC. In addition, a 5 g/100 g content of THC was observed to significantly inhibit the formation of Harman. β-CHAs and protein structures displayed good correlations, which indicated that interactions between food components may be one of the ways for exogenous additives to inhibit the formation of β-CHAs in protein foods.

Effect of sweeteners and storage on compositional and sensory properties of blackberry jams

Sweeteners of natural sources, such as sugar alcohols, are in the centre of growing interest. Their impact on the phytochemicals, antioxidant and sensory properties of blackberry jams were investigated during a 9-months storage period. Measurements on jams prepared with different sugars and sugar alcohols (sucrose, fructose, xylitol and erythritol) were performed at the date of preparation and in the 1st, 3rd, 6th, 9th month.Total polyphenol content, individual polyphenols, antioxidant properties, anthocyanin content and CIE L*a*b* colour were determined. Sensory profiles were determined by a trained panel. Sensory attributes were compared by the results of the electronic tongue and nose.Sweeteners had a significant impact on physicochemical properties and sensory attributes. Storage time also affected the sensory and compositional properties of jams. Changes in antioxidant properties did not follow a clear trend during the storage period, and antioxidant capacity was not affected significantly by the sweetening agent, but showed a significant decline from the 6th month. A positive effect of xylitol was observed in terms of a low degradation rate of anthocyanins, while their decomposition was the fastest in the fructose-containing preparation. Jams sweetened with erythritol reached significantly lower values for some sensory attributes (blackberry flavour and general taste intensity), however, they showed more intense red colour. Multiple factor analysis enabled the identification of the effect of sweetener and storage time on the pattern of the sensory data matrix. Classification according to individual sweeteners was performed successfully by the electronic tongue, but not by electronic nose.

Impact of particle size of pulverized citrus peel tissue on changes in antioxidant properties of digested fluids during simulated in vitro digestion

To examine the effect of mechanical processing for plant-based materials on antioxidant properties during digestion, relationships between the size of pulverized plant tissue and changes in antioxidant activities during simulated in vitro digestion were investigated. The citrus peel tissue was pulverized and classified into four powder fractions followed their particle size distributions as 125 − 180 μm, 180 − 355 μm, 355 − 500 μm and 500 − 710 μm. These fractions were regarded as a plant tissue model with various degrees of cell damages. Powder samples were collected during the digestion and measured their particle sizes and colors. Besides, total phenolic content and antioxidant activities of digested fluid were also evaluated. The results showed that the powder color of smaller particles were significantly changed than the bigger ones. The bio-properties of digested fluid for the bigger particle sizes comparatively retained more than smaller ones at the simulated gastric stage. It also showed mostly stable during simulated gastric or small intestinal digestion stage. This suggested that the release of bioactive compounds from plant tissues during digestion could be related to their structural attributes such as degrees of cell damages which could be affected by processing methods and conditions.

Evaluation of ACC-deaminase-producing rhizobacteria to alleviate water-stress impacts in wheat (Triticum aestivum L.) plants.

Application of plant-growth-promoting rhizobacteria (PGPR) is an environmentally sustainable option to reduce the effects of abiotic and biotic stresses on plant growth and productivity. Bacteria isolated from rain-fed agriculture field soils in the Central Himalaya Kumaun region, India, were evaluated for the production of 1-aminocyclopropane-1-carboxylic acid (ACC) deaminase. Those producing ACC deaminase in high amounts were evaluated for their potential to improve wheat (Triticum aestivum L.) plant growth under irrigated and water-stress conditions in two glasshouse experiments. Some of the isolates also showed other plant-growth-promoting (PGP) traits, e.g., N2 fixation, siderophore production, and phosphate solubilization; however, strains with higher ACC deaminase activity showed the greatest effects. These were Variovorax paradoxus RAA3; Pseudomonas spp. DPC12, DPB13, DPB15, DPB16; Achromobacter spp. PSA7, PSB8; and Ochrobactrum anthropi DPC9. In both simulated irrigated and water-stress conditions, a single inoculation of RAA3 and a consortium of DPC9 + DPB13 + DPB15 + DPB16 significantly improved wheat plant growth and foliar nutrient concentrations and caused significant positive changes in antioxidant properties compared with noninoculated plants especially under water stress. These findings imply that PGPB having ACC deaminase activity together with other PGP traits could potentially be effective inoculants to improve the growth of wheat plants in water-stressed rain-fed environments.

Thidiazuron-induced somatic embryogenesis and changes of antioxidant properties in tissue cultures of half-high blueberry plants

An efficient protocol of somatic embryogenesis (SE) has been developed for the first time in four half-high blueberry (Vaccinium corymbosum L. × V. angustifolium Ait.) cultivars. Thidiazuron (TDZ), a plant growth regulator with potential activities for shoot regeneration and shoot proliferation, was found most effective for somatic embryo formation when added to a nutrient medium at high concentration (9 µM). Although TDZ was also best for embryo germination at low concentration (2.3 µM), it was followed by zeatin at 4.6 µM for the same. Plantlets developed from SE were removed from the nutrient medium and transferred on a peat: perlite medium where 100% survival rate was acquired following the acclimatization process in a greenhouse. The concentrations of total phenolic and flavonoid contents were higher in greenhouse-grown conventionally cutting-propagated donor mother plants than those of respective SE plants for ‘St. Cloud’, ‘Patriot’ and ‘Northblue’ but not for ‘Chippewa’. The effect of propagation method and/or the older age of donor mother plants were clearly visible exclusively as the 15-year-old donor plants showed higher level of 2,2-diphenyl-1-picrylhydrazyl scavenging activity than the eight-weeks-old SE plants in all four cultivars.

Drying effects on antioxidant activity, enzyme activity, and phytochemicals of avocado ( Persea americana ) leaves

In this study, avocado leaves were dried by five different drying treatments: oven-drying at 50 and 100 °C, microwave-drying, ambient air-drying, and freeze-drying. Investigation showed that oven-drying and ambient air-drying of leaves caused decrease in antioxidant properties while microwave-drying and freeze-drying preserved them. Polyphenol oxidase (PPO) and peroxidase (POD) activities decreased notably after drying in oven at 50 and 100°C, microwave, ambient air and blanching at 100°C. However, increase in PPO was observed in freeze-dried leaves. Chlorogenic acid and rutin present in leaves showed varying decrease in drying processes except microwave-drying, and freeze-drying. Cellular antioxidant assay revealed reduced antioxidant activity in all drying treatments except for microwave-drying. Factors that affected changes in antioxidant properties by various drying processes were identified and discussed. Microwave-drying was considered to be the best drying method for avocado leaves as phenolic compounds were preserved and PPO and POD activities were deactivated. Practical applications Avocado leaves are used as herbal tea in traditional medicine and are reported to have medicinal properties such as antioxidant, anti-viral, and anti-inflammatory. Processing of fresh herbal tea leaves are required to preserve phenolic compounds and quality of the tea leaves. This study represents a comprehensive study on the effects of different drying treatments on the antioxidant activity using both in vitro and in vivo analysis and enzymatic changes of avocado leaves. The optimum drying condition found in this study will be beneficial to the tea processing industry.