Increase In Total Phenolic Content Research Articles

Impact of different ancient wheats and pseudocereals on physical, chemical, and functional properties of gevrek, cereal‐based snack product

Background and Objectives Gevrek is grissini/breadstick like snack product. In this study, whole flours of modern wheat (Esperia), ancient wheats (einkorn, emmer, and spelt) and pseudocereal (amaranth, buckwheat, and quinoa) were used in gevrek formulation instead of refined wheat flour, and the effects on the physical, nutritional, and functional properties of gevreks were researched. Findings The use of pseudocereals in the gevrek formulation decreased the lightness and yellowness value compared to the control and ancient wheat gevreks. Also, pseudocereals especially buckwheat decreased the hardness of gevreks significantly (p < .05). The phytic acid content of Esperia and buckwheat gevrek were 50.98% and 51.21% less than amaranth gevreks, respectively. The use of buckwheat and emmer contributed greatly to the increase in total phenolic content as well as antioxidant activity. Amaranth gevrek was superior in terms of Ca, Fe, and Mg content among all gevrek samples. Esperia and emmer gevreks were the most liked by the panelists when all parameters were taken into account. Conclusions The use of ancient wheats and pseudocereals in the gevrek formulation yielded products with improved protein, antioxidant activity and phenolic content, acceptable technological quality and distinctive sensory properties. Significance and Novelty Compared to traditional gevrek, our findings were the first to show that it is possible to produce nutritionally superior ancient wheat and pseudocereal-enriched functional snacks (gevrek).

The Impact of Plasma Activated Water Treatment on the Phenolic Profile, Vitamins Content, Antioxidant and Enzymatic Activities of Rocket-Salad Leaves.

Plasma activated water (PAW) recently received much attention as an alternative food preservation method. However, its effects on food quality are still scarce. This study evaluates the effect of PAW processing time on bioactive compounds of rocket-salad leaves including: 18 phenolic compounds, vitamin C, riboflavin, nicotinic acid, and nicotinamide. Moreover, the impact of PAW on both antioxidant (DPPH) and peroxidase (POD) activities was also investigated. This was performed using HPLC-DAD, HPLC-MS/MS, and spectrophotometric analysis. All treatments induced non-significant increases in total phenolic contents. However, depending on processing time, significant increases or decreases of individual phenolic compounds were observed. PAW-10 and -20 increased the ascorbic acid content to 382.76 and 363.14 mg/100 g, respectively, compared to control (337.73 mg/100 g). Riboflavin and nicotinic acid contents were increased significantly in PAW-20 (0.53 and 1.26 mg/100), compared to control (0.32 and 0.61 mg/100 g, respectively). However, nicotinamide showed non-significant increase in all treatments. Antioxidant activity improved significantly only in PAW-20, while peroxidase activity was reduced up to 36% in the longest treatment. In conclusion, PAW treatment could be an effective technique for rocket decontamination since it positively influenced the quality of rocket, improving the retention of polyphenols and vitamins.

Glucosinolates breakdown and enhanced nitrile formation in gamma irradiated minimally processed cauliflower (Brassica oleracia)

Glucosinolates (GSLs) and its degradation products from Brassica vegetables are of special importance due to diverse biological activities including health benefits. Gamma irradiation (a non-thermal post-harvest processing method) is known to extend shelf life of minimally processed cauliflower. However, the effect of gamma radiation on GSLs content and their hydrolytic products such as nitriles is less understood. In the current study, the mechanism of enhanced breakdown of major GSLs (sinigrin, glucoiberin and glucobrassicin) and formation of nitriles due to gamma irradiation was elucidated. The nitrile formation due to radiation stress was shown to be mediated by improved Fe2+ availability. The significant enhancement of nitrile formation was observed during Fe2+ supplementation studies. Gamma irradiation resulted in increase in total phenolic contents (35%), free radical scavenging activity (44%), and ferric reducing antioxidant power (FRAP) by 30%. The higher Fe2+ content was also observed in irradiated cauliflower and was maintained due to higher antioxidants (total phenolic contents) content. The change in expression of genes associated with GSLs biosynthesis was found to be not significant. Our study has illustrated the genetic and biochemical basis of GSLs reduction under radiation stress with special emphasis on role of Fe2+ in GSL metabolism after gamma irradiation.

Pre and postharvest treatments of methyl jasmonate: Maintain quality and shelf-life of Kinnow mandarin fruit during cold storage

• Pre and Postharvest MeJA application maintained the quality of Kinnow mandarin fruit during cold storage. • 0.5 mM MeJA application reduced weight loss, retained higher fruit firmness, flavonoids, carotenoids, Vitamin C, total phenols, antioxidant activity, peroxidase enzyme activity. • 0.5 mM MeJA foliar application gives better results over postharvest treatment with regard to various desirable postharvest quality traits of Kinnow mandarin fruit. Kinnow mandarin fruit were subjected to pre and postharvest treatment with four concentrations (0.1, 0.3, 0.5 and 0.7 mM) of methyl jasmonate (MeJA). Treated fruits were stored at 6 °C and 85–95% relative humidity for 40 days (d). Comparatively, pre-harvest application, retained higher moisture content, fruit firmness and TSS/acidity ratio over the after harvest treated fruits on 40 days of storage. Moreover, preharvest harvest application of MeJa (0.5 mM) maintained 2.01-fold higher flavonoids and 1.40-fold higher Vitamin C over the control. An increase in total phenolic content, antioxidant activity and peroxidase enzyme activity were reported in pre-harvest treated fruit over postharvest treatment and control at the end of storage. The principal components analysis has also shown comparatively better response of pre-harvest MeJA application to most of the postharvest desirable fruit traits over postharvest treatments. From this study, it is concluded that pre-harvest MeJA (0.5 mM) application -40 days before harvesting is more effective over postharvest aqueous application.

Evaluation of Total Phenol Content of some Common Paddy Cultivars of Odisha with the Application of Biofertilizer in Assessing Resistance to Meloidogyne graminicola

The total phenol content of four common paddy cultivars of Odisha namely Abhisek (R), Manik (MR), Bas-12 (S) and Lalat (HS) were studied under pot culture condition in the net house following CRD design under different treatments using biofertilizer Azospirillum. brasilense alone or in combinations against rice root-knot nematode Meloidogyne graminicola. The objective of the work was to study the quantitative changes in phenolic compounds content and the effect of A.brasilense in the induction of phenolic compounds on the test nematode. It was observed that there was a significant increase in total phenol content in both resistant and moderately resistant paddy cultivars Abhisek and Manik in treatment T2 (Azospirillum brasilense @ 12kg/ha at 15DAT + M. graminicola @ 1000J2 after 7days of Azospirillum inoculation) were seen higher than the susceptible variety Bas-12 and highly susceptible variety Lalat as compared to control T5 with increase percentage of 38.77%, 36.58%, 35.02% and 39.28% respectively in shoots. Similarly the trend was continued in roots containing total phenol content of 0.25mg/g in Abhisek, 0.18mg/g in Manik, 0.21mg/g in Bas-12 and 0.19mg/g in Lalat as compared to other treatments. There were increase in percentage of change (p≤0.05) in roots under treatment T3 (A alone) in all the four varieties followed by T2 (A→N), and T1 (N→A) with respect to control T5. Basically, shoots of control plants in all four cultivars were observed more content of phenolic compounds than their roots. But after M. graminicola invasion and the action of A. brasilense the amount increased in both the roots and shoots of all the cultivars. The T4 (N alone) treatment in all the R, MR, S and HS varieties were recorded higher as compare to T5 but less than the treatments T3, T2, and T1 in both roots and shoots against the test nematode, which could exacerbating for eco-friendly RKN management approach.

Enrichment of dark chocolate with free and microencapsulated white tea and jujube extracts: Impacts on antioxidant, physicochemical, and textural properties

In this study, dark chocolate was enriched with white tea (WT) and jujube extracts in form of free extract and microcapsules. Each form of two extracts was added to dark chocolate in concentrations of 1, 3, 5, and 7% w/w. The microcapsules were produced using pectin/casein (10% w/w), and their particle size distribution (PSD) and Fourier transform infrared spectroscopic analysis were performed. Phenolic content, antioxidant activity, pH, moisture content, color parameters and texture of enriched dark chocolates were measured. As expected, addition of extracts caused a significant increase in total phenolic content and antioxidant properties of dark chocolates compared to the control sample (no extract added) in both free and microencapsulated forms, with a stronger effect of WT extract than jujube extract.

Impact of germination on the proximate composition, functional properties, and structural characteristics of black soybean ( Glycine max L. Merr)

This study aimed to investigate the impact of germination on the quality of black soybean flour (BSF). The black soybeans were germinated for different time period (24, 48, and 72 h), and the impact on proximate composition, functional, structural, and antioxidant properties of the obtained flour was evaluated. Germination process resulted in significant (p ≤ 0.05) increase in protein (39.46 ± 0.08–43.30 ± 0.05 g/100 g), crude fiber (7.55 ± 0.15–10.31 ± 0.16 g/100 g), and ash (5.95 ± 0.04–6.28 ± 0.01 g/100 g) content as compared with raw black soybean flour (RBSF). Further, significant variation in color attributes, functional properties, and pasting characteristics of raw and germinated black soybean flour (GBSF) was observed. Significant increase in total phenolic content (6.76 ± 0.05 to 9.30 ± 0.04 mg GAE/g), total flavonoid content (2.45 ± 0.04 to 4.32 ± 0.02 mg QE/g), and DPPH radical scavenging activity (41.31%–60.20%) was observed post germination (24–72 h). Scanning electron micrographs (SEMs) showed that germination resulted in microstructural changes in starch and protein matrix owing to activation of hydrolytic enzymes. Further, X-ray diffraction patterns elucidate significant reduction in crystallinity of GBSF (42.54%–44.48% for 24–72 h) in comparison to RBSF (45.75%).

Antifungal activity of silver/silicon dioxide nanocomposite on the response of faba bean plants (Vicia faba L.) infected by Botrytis cinerea

Silicon (Si) and its nanomaterials could help plants cope with different negative effects of abiotic and/or biotic stresses. In this study, the antifungal role of silver/silicon dioxide nanocomposite (Ag/SiO2NC) biosynthesized using a free-cell supernatant of Escherichia coli D8 was investigated for controlling the growth parameters and yield of faba bean (Vicia faba L.) infected by Botrytis cinerea. This nanocomposite was characterized using UV–Vis spectroscopy, Fourier transform-infrared (FTIR), transmission electron microscopy (TEM), zeta analysis, and X-ray diffraction pattern (XRD). Positively charged Ag/SiO2NC (+ 31.0 mV) with spherical-shaped silver nanoparticles (AgNPs) showed strong in vitro antifungal activity with minimal inhibition concentration (MIC) value equal to 40 ppm. In vivo experiments revealed the good resistance of Ag/SiO2NC-treated plants against the B. cinerea infection due to the increase of total phenolic content, peroxidase, and polyphenol oxidase activity. The ultrastructure of Ag/SiO2NC-treated plants showed normal morphology of cells including cell membranes and ellipsoidal-shaped chloroplasts with big starch grains. The concentration of silver content in Ag/SiO2NC-treated plants was similar to the untreated control plant indicating the low realizability of AgNPs. All of these results are promising outcomes for the application of the biosynthesized Ag/SiO2NC as a safe and effective antifungal agent against B. cinerea.Graphical

Effect of the Addition of Hulless Barley Flour on the Quality of Short-Dough Cookies.

Short-dough cookies are one of the most popular cereal-based products in the world, but usually they are considered as foods with a low nutritional value. Therefore, the aim of this study was to investigate the possibility of replacing part of the wheat flour (WF) with hulless barley flour (HLBF), in order to improve the functional properties and nutritional value of the cookies. Cookies were prepared from composite flours in the ratios HLBF:WF 0:100, 25:75, 50:50, 75:25, and 100:0. The results show that as the HLBF content in the composite flour increases, the viscosity of the corresponding HLBF:WF slurries also increases, due to the high dietary fiber content (especially the high β-glucan content), which is significantly higher when HLBF is included in the formulation. The addition of HLBF decreases the spread factor of the cookies, and increases their softness compared to the control cookies (100% WF), but these changes are not statistically significant up to 50% HLBF addition. The color of the HLBF:WF cookies is not significantly affected. A significant increase in total phenolic content (TPC) and increased antioxidant capacity (AOC) are observed in the HLBF:WF cookies. In addition, sensory evaluation confirms that WF can be replaced by up to 50% with HLBF without significant deterioration of the organoleptic properties of the cookies. It can be concluded that hulless barley serves as a promising raw material if the nutritional and functional properties of cereal-based products are to be improved.

Tahini consumption exhibits beneficial effects in cardiovascular indices and antioxidant biomarkers in healthy males postprandially

Background and Aims : Sesame (Sesamum indicum L.), rich in polyunsaturated fatty acids, proteins, vitamin E and lignans is well known for its antioxidant, antihypertensive, hypolipidemic and appetite control properties. The aim of the study was to investigate the postprandial effect of tahini (sesame paste) consumption on cardiovascular indices and oxidative stress biomarkers.Methods: Research protocol was approved by the Medical Ethics Committee of ‘Laiko’ University Hospital and registered with ClinicalTrials.gov, where the full trial protocol can be accessed (Identifier: NCT04608747). After a 12-h fast, twenty healthy men (mean age: 28y, mean BMI: 25.81 kg/m2 ) consumed 50g of tahini and blood and urine samples were obtained before and 1, 2, 3 and 4h postprandially. Assessment of hemodynamic parameters was performed at 0 and 4h. Blood glucose, triglycerides, vascular adhesion molecules (ICAM-1, VCAM-1, E-selectin), ferric-reducing ability of plasma (FRAP) and total phenolic content and urinary 8-iso-prostaglandin F2α were also measured.Results: Plasma glucose was found to be significantly lower 1h (p<0.001), 3h (p=0.032) and 4h (p<0.001) after tahini consumption compared to baseline. Significant decrease in DBP (p=0.010) and pulse rate (p=0.002) was observed 4 h postprandially. Significant increases in serum triglycerides (p<0.001), flow-mediated dilatation (p=0.022) and urinary 8-iso-prostaglandin F2α levels (p=0.016) were observed 4h postprandially. Moreover, a trend of increase in total phenolic content (p=0.092) was observed 1 h postprandially. No changes were observed in other indices measured, compared to baseline.Conclusions: This is the first study to report that tahini consumption can lower blood pressure, pulse rate, improve endothelial function and may exert antioxidant properties. Background and Aims : Sesame (Sesamum indicum L.), rich in polyunsaturated fatty acids, proteins, vitamin E and lignans is well known for its antioxidant, antihypertensive, hypolipidemic and appetite control properties. The aim of the study was to investigate the postprandial effect of tahini (sesame paste) consumption on cardiovascular indices and oxidative stress biomarkers. Methods: Research protocol was approved by the Medical Ethics Committee of ‘Laiko’ University Hospital and registered with ClinicalTrials.gov, where the full trial protocol can be accessed (Identifier: NCT04608747). After a 12-h fast, twenty healthy men (mean age: 28y, mean BMI: 25.81 kg/m2 ) consumed 50g of tahini and blood and urine samples were obtained before and 1, 2, 3 and 4h postprandially. Assessment of hemodynamic parameters was performed at 0 and 4h. Blood glucose, triglycerides, vascular adhesion molecules (ICAM-1, VCAM-1, E-selectin), ferric-reducing ability of plasma (FRAP) and total phenolic content and urinary 8-iso-prostaglandin F2α were also measured. Results: Plasma glucose was found to be significantly lower 1h (p<0.001), 3h (p=0.032) and 4h (p<0.001) after tahini consumption compared to baseline. Significant decrease in DBP (p=0.010) and pulse rate (p=0.002) was observed 4 h postprandially. Significant increases in serum triglycerides (p<0.001), flow-mediated dilatation (p=0.022) and urinary 8-iso-prostaglandin F2α levels (p=0.016) were observed 4h postprandially. Moreover, a trend of increase in total phenolic content (p=0.092) was observed 1 h postprandially. No changes were observed in other indices measured, compared to baseline. Conclusions: This is the first study to report that tahini consumption can lower blood pressure, pulse rate, improve endothelial function and may exert antioxidant properties.

The role of seaweed extract on improvement drought tolerance of wheat revealed by osmoprotectants and DNA (cpDNA) markers

Drought stress is one of the most severe abiotic stresses affecting adversely plant growth, crop production, and various metabolic processes. Using seaweed extract in mitigating water stress adverse effects is highly important for plant production. The present study discussed the physiological role of seaweed extract (Sargassum denticulatum) in improving wheat tolerance to water stress.Water stress (40% of field capacity) caused significant decreases in wheat plant growth parameters (shoot height, fresh, and dry weights of the shoot) as well as with significant decreases in chlorophyll content and starch. Total soluble sugars, free amino acids, proline, and phenolic compounds contents increased in stressed wheat plants irrigated every three weeks compared with control plants. The foliar application of seaweed extract 2% enhanced all growth and yield parameters and more accumulation of the organic solutes in leaves of water-stressed plants. These increases correlated with significant increases in total phenolic contents as compared with control plants. The trnL intron and psbA-trnH intergenic regions of cpDNA were amplified from extracted total genomic DNA. The results indicated that the variation among psbA-trnH intergenic region was more than trnL intron region to distinct the variation of wheat treatments as responsible to water deficit.Foliar spray of seaweeds extract was effective in improving wheat performance by enhancing compatible osmolytes, antioxidant compounds and enhancing variation among non-coding chloroplast DNA (cpDNA) regions trnL intron and psbA-tnH as a response to water deficit.

Analysis of Phenol, Reducing Sugar, and Chlorophyll of Dendrobium sp. plantlet after induction of fusaric acid In Vitro

Orchids are ornamental plants with varied and beautiful flower colors and are much favored by the public. Orchid plants have a higher economic value when compared to other ornamental plants, both as cut flowers and potted flowers. In the process of growth, orchid plants are disturbed, namely Fusarium wilt disease caused by Genus Fusarium which can produce a toxin compound, namely fusaric acid which is widely used in in vitro selection of plants. Plant resistance can be formed through the induction of fusaric acid compounds. Induced resistance is an alternative way to obtain disease-resistant plants because plants are able to create natural resistance mechanisms. The purpose of this study was to determine the concentration of tolerant fusaric acid to select Dendrobium orchid plantlets with optimal growth and specific expression characters of Dendrobium orchid plantlets based on phenol content, reducing sugar content, and total chlorophyll content, chlorophyll a and chlorophyll b. The results of this study indicated that there was an increase in total phenol content, reducing sugar content, and total chlorophyll content, chlorophyll a and chlorophyll b along with the addition of fusaric acid concentration.

The Content of Certain Groups of Phenolic Compounds and the Biological Activity of Extracts of Various Halophyte Parts of Spergularia marina (L.) Griseb. and Glaux maritima L. at Different Levels of Soil Salinization.

Halophyte plants are known for their resistance to harsh environmental conditions associated with excess salts in their habitats. Their resistance to salinization is due, among other things, to their high ability to detoxify free radicals, owing to the relatively high content of antioxidants. On the coast of the Baltic Sea and in the lagoons, there are several rare halophyte species included in the Red Book of the Kaliningrad Region (Russia) and the Baltic region, such as Spergularia marina (L.) Griseb. and Glaux maritima L. The aim of the research was to study the accumulation of certain groups of phenolic compounds in different parts of S. marina and G. maritima plants under conditions of weak and strong soil salinity, as well as to analyze the antioxidant, antibacterial, and fungicidal activity of extracts of the studied plant species. The present study showed an increase in total phenolic content in the roots and shoots of S. marina, and the shoots of G. maritima, in response to increased soil salinity. At the same time, the total content of flavonoids in all the studied parts of the two plant species remained unchanged. However, the content of individual flavonoids (hesperetin, epicatechin, apigenin derivative, luteolin derivative) in S. marina increased, for G. maritima there was a tendency to reduce the content of flavonoids in roots and shoots with an increase in soil salinity. There was an increase in the total content of hydroxycinnamic acids in the roots of Glaux maritima, as well as an increase in the content of protocatechuic acid in the roots and shoots of Spergularia marina. A positive relationship was established between the antioxidant activity of S. marina root extracts and the total content of phenolic compounds, as well as G. maritima shoots extracts and the total content of phenolic compounds. Extracts of S. marina showed no antibacterial activity against Escherichia coli and Bacillus subtilis, and weak fungicidal activity of stem extracts and inflorescences grown on soils, with high levels of salinities, was detected against Candida albicans. The extracts of roots and shoots from G. maritima showed weak antimicrobial and fungicidal activity.

Changes in Phenolic Compound and Antioxidant Activity of Germinated Broccoli, Wheat, and Lentils during Simulated Gastrointestinal Digestion.

The consumption of sprouts has increased as the germination process causes changes in the chemical composition of the seeds, improving their nutritional value. The aim of this work was to compare the total phenolic content and antioxidant capacity of broccoli, lentils and wheat sprouts before and after in vitro digestion, and the total phenolic content and antioxidant capacity between seeds and sprouts. Broccoli and wheat showed no difference in total phenolic content before and after germination, while lentils showed a significant decrease in total phenolic content after germination. The antioxidant capacity of broccoli and wheat increased after germination. After simulated digestion, the total phenolic content and antioxidant activity of broccoli sprouts significantly decreased during digestion in the gastric phase compared to the sprouts before digestion. Lentil sprouts did not show a decrease in total phenolic content during the gastric phase of digestion compared to the sprouts before digestion. However, they showed a significant increase in total phenolic content during the enteric phase. Finally, wheat sprouts showed a significant increase in total phenolic content and antioxidant activity during the gastric phase of digestion compared to grain before digestion. The germination process may increase the antioxidant capacity of sprouts, although this is not always related to the phenolic compound.

Fabrication and characterization of a smart film based on cassava starch and pomegranate peel powder for monitoring lamb meat freshness.

Nowadays, the development of pH‐sensitive smart edible films using biopolymers and natural plant extracts (especially those rich in anthocyanins) has attracted much attention. Therefore, in this study, the intelligent edible film was produced and characterized using cassava starch and pomegranate peel powder (PPP) and the possibility of using production films to monitor the freshness of lamb meat. The smart films were prepared using different concentrations of PPP (2, 4, 6, and 8% w/w) and the solvent casting method. The results showed that the incorporation of PPP had a significant effect on the mechanical parameters of the starch films. With increasing the levels of PPP, the color of the films became darker and redder. Increasing the PPP levels also led to an increase in total phenol content (TPC) (from 0 to 13 mg GAE (gallic acid equivalent)/g) and antioxidant activity (from 0% to 70% DPPH (1,1‐diphenyl‐2‐picryl hydrazyl) radical scavenging) of the produced films (p < .05). The intelligent film was used in the lamb meat packaging, and the color of the film changed from red to green during the storage period at 25°C. The amount of total volatile basic nitrogen (TVB‐N) in the meat could be detected by color changes of the intelligent films. Finally, this study demonstrated that the film based on cassava starch and PPP could be used as an intelligent and pH‐sensitive film to monitor the freshness of meat and meat products.

Changes in Functional Compounds, Volatiles, and Antioxidant Properties of Culinary Herb Coriander Leaves (Coriandrum sativum) Stored Under Red and Blue LED Light for Different Storage Times.

This study evaluated the influence of red (630–640 nm) and blue (450 nm) light-emitting diodes (LED) lights on the changes in antioxidant constituents, activity, volatile compounds, and overall acceptability of Coriander leaves (Coriandrum sativum) during post-harvest storage. Coriander leaves are harvested at commercial maturity, packed in polyethylene terephthalate punnets, and exposed for 2 h to the red LED or blue LED lights separately during storage at 5°C and 85% RH up to 9 days. Coriander leaves exposed to the white light (2 h) and continuous darkness served as controls. Samples were removed from cold storage at 3, 6, and 9 days to determine the antioxidant constituents, their activity, retention of volatile compounds, and overall acceptance. Coriander leaves exposed to red and blue LED lights for 2 h showed a commercially allowable mass loss of up to 9 days compared to the other treatments. Compared to those exposed to red LED light (2 h) and the control, leaves exposed to blue LED light for 2 h and stored for 3–9 days showed a reduction in colour change (ΔE). The β-carotene content significantly peaked at 44.55% on day 6 in coriander leaves exposed to the red LED light. However, leaves exposed to blue and red LED light showed an increase in total phenolic content by 9.34 and 6.39% on day 9, respectively. Exposure to blue LED lights increased the antioxidant activities (DPPH, ABTS, and FRAP), quercetin content, and the concentration of typical coriander aroma, 2-tridecenal, 2-dodecenal, (E), and Z-9-19 hexadecenal on day 9. Coriander leaves exposed to blue LED light (2 h) and stored up to day 9 scored a higher acceptance level by the panellists. Thus, blue light LED treatment during post-harvest storage can be recommended to retain the antioxidant property of coriander leaves.

Effects of extrusion processing on the bioactive constituents, in vitro digestibility, amino acid composition, and antioxidant potential of novel gluten-free extruded snacks fortified with cowpea and whey protein concentrate

This study aimed to develop novel gluten-free snacks from rice flour, cowpea and whey protein concentrate (WPC) enriched with bioactive and antioxidant properties. The effects of extrusion on bioactive compounds (sucrose-galactosyl oligosaccharides, insoluble dietary fibre, resistant starch, phytic acid, trypsin inhibitory activity), protein digestibility, amino acid composition, total phenolic content and antioxidant properties were evaluated by comparing raw formulations and extruded snacks. Rice flour (100%) was used as a control. Extrusion increased the oligosaccharides (2–3 fold) and resistant starch (1–3 fold), whereas the insoluble fibre content was not significantly affected. Extrusion increased in vitro protein digestibility (p < 0.05) and amino acid composition in snacks. Extruded and raw samples enriched with cowpea and WPC had an increase in total phenolic content (TPC) and antioxidant activity. Extrusion significantly reduced the TPC and antioxidant properties of extruded snacks compared to their raw counterparts. The results obtained in this study respond to the growing interest of the food industry to cater to consumer demand for healthy novel gluten-free expanded snacks with bioactive compounds.

Improved plant heat shock resistance is introduced differently by heat and insect infestation: the role of volatile emission traits

Heat stress is one of the most important abiotic stresses confronted by plants under global climate change. Plant exposure to abiotic or biotic stress can improve its tolerance to subsequent severe episodes of the same or different stress (stress priming), but so far there is limited comparative information about how pre-exposures to different abiotic and biotic elicitors alter plant resistance to severe heat stress. We exposed the perennial herb Melilotus albus Medik., a species rich in secondary metabolites, to moderate heat stress (35°C) and greenhouse whitefly (Trialeurodes vaporariorum West.) infestation to comparatively determine whether both pre-treatments could enhance plant tolerance to the subsequent heat shock (45°C) stress. Plant physiological responses to stress were characterized by photosynthetic traits and volatile organic compound emissions through 72h recovery. Heat shock treatment reduced net assimilation rate (A) and stomatal conductance in all plants, but heat-primed plants had significantly faster rates of recovery of A than other plants. By the end of the recovery period, A in none of the three heat shock-stressed groups recovered to the control level, but in whitefly-infested plants it reached the pre-heat shock level. In heat-primed plants, the heat shock treatment was associated with a fast rise of monoterpene emissions, and in whitefly-infested plants with benzenoid emissions and an increase in total phenolic content.

The Impact of Fermentation on Bee Pollen Polyphenolic Compounds Composition.

Bee-collected pollen is one of the most valuable natural products. However, the pollen cell walls limit the digestibility and release of nutrients to the human body. Solid-state lactic acid fermentation can be used to ease the release of bioactive compounds from the pollen cell. The aim of this research was to determine the impact of a solid-state lactic acid fermentation process on biologically active compound composition and antioxidant activity of bee-collected pollen from various European regions (Italy, Netherlands, Lithuania, Poland, Sweden, Denmark, Malta, Slovakia, and Spain). Spontaneous fermentation and fermentation using an L. rhamnosus culture were performed. The total content of phenolic compounds, total content of flavonoids, and radical (DPPH) scavenging activity were measured by spectrophotometric tests, while UPLC was employed for quantification of phenolic compounds. The determined fermentation positive effects included an increase of total phenolic content by 1.4–2.3 times, total flavonoid content by 1.1–1.6 times, and radical scavenging activity by 1.4–2.3 times. Naringenin (21.09–135.03 µg/g), quercetin (6.62–78.86 µg/g), luteolin (29.41–88.90 µg/g), and rutin (21.40–89.93 µg/g) were the most abundant flavonoids in all samples; however, their variation level was both geographical in origin and fermentation-type dependent. Fermentation increased the content of phenolic acids with high antioxidant potentials such as ellagic, ferulic and caffeic, while reduction of chlorogenic acid was determined.

Interfacial Properties and Antioxidant Activity of Whey Protein-Phenolic Complexes: Effect of Phenolic Type and Concentration

Whey protein is a common food additive for enhancing product stability and texture, while phenolics are considered food antioxidants. As a consequence, combining whey protein with phenolics is an effective way to improve protein functionality while also maintaining polyphenol bioactivity. Herein, the functional properties and antioxidant activity of whey protein modified with various types and concentrations of oxidized phenolic compounds, including gallic acid (OGA), ferulic acid (OFA), and tannic acid (OTA), were studied. In general, the modified whey protein had a decrease in free amino content, but an increase in total phenolic content. Whey protein modified with 5% OTA showed the highest total phenolic content and the lowest free amino content. Modification of whey protein with OTA and OGA resulted in a loss of surface hydrophobicity in contrast to whey protein modified with OFA. However, no significant difference in surface activity including foam and emulsion properties in the whey protein with/without modification was observed. The modified whey protein had an increase in antioxidant activity when compared with that of the control.