μM Trolox Equivalents Research Articles

Investigation of antioxidant activity of protein hydrolysate derived from baby clam (Corbiculidae sp.) broth

This study is aimed to bring baby clam broth (BCB) into antioxidant proteolysate utilizing enzymatic hydrolysis. Chemical compositions of BCB were firstly analyzed, followed by investigating the effects of enzymatic hydrolysis parameters involving in enzyme type, pH, temperature, enzyme:substrate (E:S) ratio and hydrolysis time on antioxidant of BCB proteolysate. It can be seen from the result that the BCB owned the moisture content, protein content, lipid content, and ash content of 97.55±0.89%, 1.52±0.16%, 0.09±0.02%, and 0.37±0.04%, respectively. The BCB proteolysate, under the hydrolysis condition including Flavourzyme, pH 7, 50°C, E:S ratio of 5 U/g protein and hydrolysis time of 50 min, exhibited the highest 2,2'-Azino-bis(3-ethylbenzthiazoline-6-sulfonic acid) cation ratio (ABTS●+) scavenging activity of 770.67±28.33 µM Trolox Equivalent (µM TE) (7.1 and 2.5 times lower than those of vitamin C and butylated hydroxytoluene (BHT), in order) and ferric reducing antioxidant power (FRAP) value of 245.26±7.37 µM TE (11.6 and 4.0 folds lower than those of vitamin C and BHT, respectively). This study suggests a new use of the BCB, antioxidant proteolysate which could be applied as a functional food or natural antioxidant additive, substituting for synthetic compounds.

Isolation and Antitrypanosomal Characterization of Furoquinoline and Oxylipin from Zanthoxylum zanthoxyloides.

In the absence of vaccines, there is a need for alternative sources of effective chemotherapy for African trypanosomiasis (AT). The increasing rate of resistance and toxicity of commercially available antitrypanosomal drugs also necessitates an investigation into the mode of action of new antitrypanosomals for AT. In this study, furoquinoline 4, 7, 8-trimethoxyfuro (2, 3-b) quinoline (compound 1) and oxylipin 9-oxo-10, 12-octadecadienoic acid (compound 2) were isolated from the plant species Zanthoxylum zanthoxyloides (Lam) Zepern and Timler (root), and their in vitro efficacy and mechanisms of action investigated in Trypanosoma brucei (T. brucei), the species responsible for AT. Both compounds resulted in a selectively significant growth inhibition of T. brucei (compound 1, half-maximal effective concentration EC50 = 1.7 μM, selectivity indices SI = 74.9; compound 2, EC50 = 1.2 μM, SI = 107.3). With regards to effect on the cell cycle phases of T. brucei, only compound 1 significantly arrested the second growth-mitotic (G2-M) phase progression even though G2-M and DNA replication (S) phase arrest resulted in the overall reduction of T. brucei cells in G0-G1 for both compounds. Moreover, both compounds resulted in the aggregation and distortion of the elongated slender morphology of T. brucei. Analysis of antioxidant potential revealed that at their minimum and maximum concentrations, the compounds exhibited significant oxidative activities in T. brucei (compound 1, 22.7 μM Trolox equivalent (TE), 221.2 μM TE; compound 2, 15.0 μM TE, 297.7 μM TE). Analysis of growth kinetics also showed that compound 1 exhibited a relatively consistent growth inhibition of T. brucei at different concentrations as compared to compound 2. The results suggest that compounds 1 and 2 are promising antitrypanosomals with the potential for further development into novel AT chemotherapy.

Effect on Adipose Tissue of Diabetic Mice Supplemented with n-3 Fatty Acids Extracted from Microalgae.

BackgroundType 2 Diabetes Mellitus (T2DM) is considered a chronic noncommunicable disease in which oxidative stress is expected as a result of hyperglycaemia. One of the most recent approaches is the study of microalgae fatty acids and their possible antioxidant effect.ObjectiveThis study aimed to analyse the effect of supplementation with n-3 fatty acids extracted from microalgae on the total antioxidant capacity (TAC) and lipid peroxidation of adipose tissue and plasma from diabetic (db/db) and healthy (CD1) mice.MethodsMice were supplemented with lyophilized n-3 fatty acids extracted from microalgae or added to the diet, from week 8 to 16. TAC assay and Thiobarbituric Acid Reactive Substances assay (TBARS) were performed on adipose tissue and plasma samples.ResultsThe supplementation of lyophilized n-3 fatty acids from microalgae increased the total antioxidant capacity in adipose tissue of diabetic mice (615.67μM Trolox equivalents vs 405.02μM Trolox equivalents from control mice, p<0.01) and in the plasma of healthy mice (1132.97±85.75μM Trolox equivalents vs 930.64±32μM Trolox equivalents from modified diet mice, p<0.01). There was no significant effect on lipid peroxidation on both strains.ConclusionThe use of n-3 fatty acids extracted from microalgae could be a useful strategy to improve total antioxidant capacity in T2DM.

Biochemical and functional properties of wheat middlings bioprocessed by lactic acid bacteria.

The present study aimed to investigate the bioprocessing of wheat middlings with different lactic acid bacteria (LAB) in order to improve biological activities of this by-product of wheat flour production. The concentration of lactic acid, reducing sugars, and total phenolics, as well as antioxidant, antibrowning, antibacterial and prebiotic activities of fermented samples were analyzed. All LAB strains were capable to growth on wheat middlings, and pH decreased in the medium associated with lactic acid production during cultivation. Samples inoculated with Lactobacillus plantarum DSM20174 presented the maximum growth, lactic acid concentration above 2mg/ml, and pH values around 3.8. The amount or reducing sugars decreased after 24hr growth, except for maltose. Bioprocessed wheat middlings exhibited antioxidant, antibrowning, antibacterial, and prebiotic properties, related with the increase of total phenolic content. Highest values for antioxidant activities were obtained for L. plantarum and Streptococcus thermophilus strains, reaching values around 400 and 640 μM Trolox equivalents (TE) ml-1 for 2,2-diphenyl-1-picrylhydrazyl (DPPH) and ferric ion reducing antioxidant power (FRAP) assays, respectively. Bioprocessing techniques using LAB can be an interesting approach to improve the availability of compounds with health-promoting properties from lignocellulosic waste material. PRACTICAL APPLICATIONS: The processing of secondary products from wheat milling can represent an important benefit to the industry. Wheat middlings bioprocessed with LAB showed improved biological activities and may represent an interesting ingredient to be incorporated in food and feed formulations.

Pig Skin Gelatin Hydrolysates Attenuate Acetylcholine Esterase Activity and Scopolamine-induced Impairment of Memory and Learning Ability of Mice.

The protective effect of pig skin gelatin water extracts (PSW) and the low molecular weight hydrolysates of PSW generated via enzymatic hydrolysis with Flavourzyme® 1000L (LPSW) against scopolamine-induced impairment of cognitive function in mice was determined. Seventy male ICR mice weighing 20–25 g were randomly assigned to seven groups: Control (CON); scopolamine (SCO, 1 mg/kg B.W., intraperitoneally (i.p.); tetrahydroaminoacridine 10 [THA 10, tacrine; 10 mg/kg B.W. per oral (p.o.) with SCO (i.p.)]; PSW 10 (10 mg/kg B.W. (p.o.) with SCO (i.p.); PSW 40 (40 mg/kg B.W. (p.o.) with SCO (i.p.); LPSW 100 (100 mg/kg B.W. (p.o.) with SCO (i.p.); LPSW 400 (400 mg/kg B.W. (p.o.) with SCO (i.p.). All treatment groups, except CON, received scopolamine on the day of the experiment. The oxygen radical absorbance capacity of LPSW 400 at 1 mg/mL was 154.14 μM Trolox equivalent. Administration of PSW and LPSW for 15 weeks did not significantly affect on physical performance of mice. LPSW 400 significantly increased spontaneous alternation, reaching the level observed for THA and CON. The latency time of animals receiving LPSW 400 was higher than that of mice treated with SCO alone in the passive avoidance test, whereas it was shorter in the water maze test. LPSW 400 increased acetylcholine (ACh) content and decreased ACh esterase activity (p<0.05). LPSW 100 and LPSW 400 reduced monoamine oxidase-B activity. These results indicated that LPSW at 400 mg/kg B.W. is a potentially strong antioxidant and contains novel components for the functional food industry.

The Metabolite Urolithin-A Ameliorates Oxidative Stress in Neuro-2a Cells, Becoming a Potential Neuroprotective Agent.

Urolithin A is a metabolite generated from ellagic acid and ellagitannins by the intestinal microbiota after consumption of fruits such as pomegranates or strawberries. The objective of this study was to determine the cytoprotective capacity of this polyphenol in Neuro-2a cells subjected to oxidative stress, as well as its direct radical scavenging activity and properties as an inhibitor of oxidases. Cells treated with this compound and H2O2 showed a greater response to oxidative stress than cells only treated with H2O2, as mitochondrial activity (MTT assay), redox state (ROS formation, lipid peroxidation), and the activity of antioxidant enzymes (CAT: catalase, SOD: superoxide dismutase, GR: glutathione reductase, GPx: glutathione peroxidase) were significantly ameliorated; additionally, urolithin A enhanced the expression of cytoprotective peroxiredoxins 1 and 3. Urolithin A also acted as a direct radical scavenger, showing values of 13.2 μM Trolox Equivalents for Oxygen Radical Absorbance Capacity (ORAC) and 5.01 µM and 152.66 µM IC50 values for superoxide and 2,2-diphenyss1-picrylhydrazyl (DPPH) radicals, respectively. Finally, inhibition of oxidizing enzymes, such as monoamine oxidase A and tyrosinase, was also detected in a dose-dependent manner. The cytoprotective effects of urolithin A could be attributed to the improvement of the cellular antioxidant battery, but also to its role as a direct radical scavenger and enzyme inhibitor of oxidases.

Ultrasound-Assisted Extraction of GAC Peel: An Optimization of Extraction Conditions for Recovering Carotenoids and Antioxidant Capacity

The peel of Gac fruit (Momordica cochinchinensis Spreng.), which is considered as waste of Gac processing, has been found to possess high levels of carotenoids and other antioxidants. This study aimed at determining the optimal conditions of an ultrasound-assisted extraction for recovering carotenoids and antioxidant capacity from Gac peel. A response surface methodology using the Box–Behnken design was employed to investigate the impact of extraction time, temperature and ultrasonic power on the recovery of total carotenoid and antioxidant capacity. The results showed that an extraction time of 76 min, temperature of 50 °C and ultrasonic power of 250 W were the optimal conditions for the extraction. The experimental carotenoid yield and antioxidant capacity obtained under the optimal extraction conditions were validated as 269 mg/100 g DW (dry weight) and 822 µM TE (Trolox equivalent)/100 g DW, respectively. These values were not significantly different from the values predicted by the models. The HPLC analysis for carotenoid composition showed that β-carotene, lycopene and lutein were the principal carotenoids of the extract, which constitute 86% of the total carotenoid content. Based on the obtained results, the ultrasound-assisted extraction using ethyl acetate under the above optimal conditions is suggested for the simultaneous recovery of carotenoids and antioxidant capacity from Gac peel.

2,2’-Diphenyl-1-picrylhydrazyl and 2,2′-azinobis-(3-ethyl-benzothiazoline-6-sulfonic acid) scavenging assay of Extract and Fractions of Rambutan (Nephelium Lappaceum L.) Seed

This research was intended to evaluate the antiradical activity of extracts and fractions of rambutan seed using 2,2’- diphenyl-1-picrylhydrazyl (DPPH) and 2,2′-azinobis-(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS•+). The powder of rambutan seed was subjected to maceration with methanol. The methanolic extract obtained was then fractionated using petroleum ether (PE), dichloromethane (DCM) and ethyl acetate (EA) to obtain PE, DCM and EA fractions, respectively. The methanol extract and fractions were then assayed for antiradical activities and phenolics and flavonoid contents.The results showed that EA fraction has lowest IC50 values among extract and fractions evaluated, i.e. 244.6 ± 2.1 μg/ml using DPPH radical. Using ABTS radical, EA fraction (0.1%) also revealed the highest antiradical activity of 643.4 ± 34.9 μM trolox equivalent. However, these antiradical activities were lower than those in positive controls used (vitamin C and vitamin E). The antiradical activities of extract and fractions correlated with total phenolics and flavonoid contents. The seed of rambutan fruit could be exploited as natural antioxidants to be used in food supplements.&#x0D; Dhaka Univ. J. Pharm. Sci. 18(2): 145-152, 2019 (December)

Human Semen Samples with High Antioxidant Reservoir May Exhibit Lower Post-Cryopreservation Recovery of Sperm Motility.

Cryopreservation-thawing of human semen was found to reduce the level of antioxidant activity surrounding the sperm, which may negatively affect post-cryopreservation (post-thaw) recovery of sperm motility. Therefore, the current manufactured cryoprotectant media have been supplemented with certain antioxidants to preserve the loss in seminal antioxidant activity. In this study, we aimed to explore the correlation between total antioxidant capacity (TAC) of human semen samples before cryopreservation and the post-thaw recovery of sperm motility. Normal semen specimens (n = 77) were recruited in this study. Sperm motility was measured for each semen sample before and after cryopreservation and the post-thaw recovery of sperm motility was calculated. Seminal TAC was measured spectrophotometrically before cryopreservation for each semen sample using the sensitive cupric ion-reducing antioxidant capacity (CUPRAC) method. The results from this study showed that the post-thaw recovery of sperm motility is negatively correlated (p = 0.0404, p = 0.0402) with the absorbance at 450 nm and the values of seminal TAC in terms of µM Trolox equivalents, as evaluated by CUPRAC, respectively. In conclusion, the total antioxidant reservoir in each ejaculated semen specimen could be a factor in determining the post-thaw recovery of sperm motility toward lower recovery for semen specimens of high antioxidant content.

Porcine Breed, Sex, and Production Stage Influence the Levels of Health Status Biomarkers in Saliva Samples.

In this study, the influence of several factors such as breed, sex, and production stage over the normal range values of salivary biomarkers of health status was evaluated in pigs. A total of 409 pigs of 2 different breeds (conventional Large White × Duroc and Iberian pigs) were included in the study. Animals were divided into different groups according to their sex (male or female) and the stage of the production cycle they were in (post-weaning, nursery, fattening, and finishing). The levels of an inflammatory marker, adenosine deaminase (ADA), and two acute phase proteins, C-reactive protein (CRP) and haptoglobin (Hp) were measured in saliva samples. Moreover, the total antioxidant capacity level (TAC) was quantified for the first time in porcine saliva; therefore, an analytical validation and stability analysis during storage at −80°C were also performed. Differences according to breed were observed for all the markers studied; thus, the influence of age and sex on the normal range values were studied separately for conventional and Iberian pigs. In Large White × Duroc pigs the overall median values of ADA, CRP, Hp and TAC were 282 U/L, 10.49 ng/mL, 0.88 μg/mL, and 21.73 μM Trolox equivalents, respectively. However, higher values of inflammatory marker and acute phase proteins were observed in males at the initial stages of the production cycle, while females presented higher values when they had reached sexual maturity. In Iberian pigs the overall median values observed were 585 U/L, 4.81 ng/mL, 0.63 μg/mL, and 21.21 μM Trolox equivalents for ADA, CRP, Hp, and TAC respectively with slight differences in the influence of the studied factors. Sex differences were not observed in the levels of acute phase proteins in Iberian pigs, probably due to the castration of males during the first days of life; however, ADA levels were found to be higher in male pigs at the end of the production cycle. It could be concluded that breed, sex, and production stage influence the range values of salivary markers of health status in pigs and should be taken into account to further establish reference intervals.

Physicochemical and antioxidant properties of gelatin-based films containing oily tomato extract (Solanum lycopersicum L.)

ABSTRACTThe aim of this work was to evaluate the effects of oily tomato extract (OTE) at concentrations of 0, 1, 3 and 5% on the physicochemical and antioxidant properties of gelatin-based films. Characterization of the extract showed lycopene and β-carotene concentrations of 159.15 and 20.38 μg/mL, respectively. The results showed that the addition of OTE was associated with a decrease in moisture content, a lower solubility, a lower water vapor permeability, and a lower Young’s modulus, while the elongation percentage showed a significant increase. The addition of OTE improved the barrier properties of the films against UV and visible light. The higher the OTE concentration was, the greater the amounts of lycopene and β-carotene within the films, and therefore, the higher the antioxidant activity was (2.49 μM Trolox equivalents per g of film). The results suggest that the addition of OTE to gelatin-based films can improve their mechanical properties and increase their antioxidant capacity.

Investigation of antioxidant capacity of peptide fractions from the Tra catfish by-product-derived proteolysate using Flavourzyme® 500 mg

In this study, the antioxidant potential of peptide fractions isolated from the Tra catfish (Pangasius hypophthalmus) by-product-derived hydrolysate using ultrafiltration centrifugal devices with 3 distinct molecular-weight cutoffs (MWCOs) of 5KDa, 10KDa, and 30KDa was investigated. Firstly, the chemical composition of the Tra catfish byproducts was analyzed. The result showed that the Tra catfish by-products contained 58.5% moisture, 33.9% crude protein, 50.1% crude lipid and 15.8% ash (on dry weight basis). Secondly, the effects of enzyme content, hydrolysis time on the antioxidant activity of the hydrolysate were studied using DPPH• (2,2-diphenyl-1-picrylhydrazyl) radical scavenging method (DPPH• SM), and FRAP (ferric reducing antioxidant potential) method. Flavourzyme® 500 MG was used for hydrolysis. The result revealed that the antioxidant activity of the proteolysate reached the peak when the hydrolysis time was 3h, enzyme/substrate (E/S) ratio was 25 U/g protein, hydrolysis temperature was 500C, pH was 7, and the degree of hydrolysis (DH) of the hydrolysate reached 37.4%. Next, the proteolysate was further fractionated using MWCOs of 5KDa, 10KDa, and 30KDa and the peptide fractions were investigated for their antioxidant activity. The result showed that the &lt;5KDa fraction showed strongest antioxidant activity with the 50% DPPH• inhibition concentration (IC50) of 3079.34±75.29 μg/mL and FRAP value of 611.28±4.5 μM Trolox equivalent. The second strongest fraction was 5-10KDa with the IC50 and FRAPS value of 4709.3 ± 222.22 μg/mL and 323.62±2.54 μM Trolox equivalent, respectively. The 10-30KDa fraction showed weakest antioxidant capacity with the IC50 of 5847.73 ± 128.68 μg/mL and FRAP value of 291.4±2.65 μM Trolox equivalent. The antioxidant peptides derived from Tra catfish by-products proteolysate have the potential to be used as natural antioxidant ingredients in pharmaceutical and food industry.

Location-dependent effects of trauma on oxidative stress in humans.

Though circulating antioxidant capacity in plasma is homeostatically regulated, it is not known whether acute stressors (i.e. trauma) affecting different anatomical locations could have quantitatively different impacts. For this reason, we evaluated the relationship between the anatomical location of trauma and plasma total antioxidant capacity (TAC) in a prospective study, where the anatomical locations of trauma in polytraumatic patients (n = 66) were categorized as primary affecting the brain -traumatic brain injury (TBI)-, thorax, abdomen and pelvis or extremities. We measured the following: plasma TAC by 2 independent methods, the contribution of selected antioxidant molecules (uric acid, bilirubin and albumin) to these values and changes after 1 week of progression. Surprisingly, TBI lowered TAC (919 ± 335 μM Trolox equivalents (TE)) in comparison with other groups (thoracic trauma 1187 ± 270 μM TE; extremities 1025 ± 276 μM TE; p = 0.004). The latter 2 presented higher hypoxia (PaO2/FiO2 272 ± 87 mmHg) and hemodynamic instability (inotrope use required in 54.5%) as well. Temporal changes in TAC are also dependent on anatomical location, as thoracic and extremity trauma patients’ TAC values decreased (1187 ± 270 to 1045 ± 263 μM TE; 1025 ± 276 to 918 ± 331 μM TE) after 1 week (p < 0.01), while in TBI these values increased (919 ± 335 to 961 ± 465 μM TE). Our results show that the response of plasma antioxidant capacity in trauma patients is strongly dependent on time after trauma and location, with TBI failing to induce such a response.

In Vitro Antioxidant Activities of Phenols and Oleanolic Acid from Mango Peel and Their Cytotoxic Effect on A549 Cell Line.

Mango peel, the main by-product of juice processing, possesses appreciable quantities of bioactive phenolic compounds and is worthy of further utilization. The present work reports for the first time the HPLC analysis and in vitro antioxidant evaluation of mango peel phenols (MPPs) and their cytotoxic effect on the A549 lung cancer cell line. These results indicated that mango peel has the total phenolic content of 723.2 ± 0.93 mg·kg−1 dry mango peel (DMP), which consisted mainly of vanillic aldehyde, caffeic acid, chlorogenic acid, gallic acid, procyanidin B2 and oleanolic acid. Antioxidant assays showed that MPPs had strong antioxidant activities, with 92 ± 4.2% of DPPH radical scavenging rate, 79 ± 2.5% of ABTS radical inhibition rate and 4.7 ± 0.5 μM Trolox equivalents per kg−1 DMP of ferric reducing power. Gallic acid possess a stronger antioxidant capacity than other phenols. In vitro cytotoxic tests suggested that mango peel extract (MPE) had an IC50 value of 15 mg·mL−1 and MPPs had a stronger inhibitory effect on the A549 cell line. Oleanolic acid exhibited the strongest cytotoxicity, with an IC50 value of 4.7 μM, which was similar with that of the positive control 5-fluorouracil.

Anti-aging effects of black raspberry extract on cataract, alopecia, skin whitening, and weight loss

Background: To maintain good health, it is important to eliminate extra reactive oxygen generated in the body. Furthermore, ingesting foods containing antioxidants is beneficial. The oxygen radical absorbance capacity (ORAC) values for black raspberry extract (BRE), blueberry extract (BBE), and raspberry extract (RBE) are 62, 66, and 49 µM Trolox equivalents (TE)/g respectively. These values are higher than those for typical antioxidant foods that have been discovered so far (3–30 µM TE/g). Our aim was to find new functionality from the food with the high ORAC value. Therefore, we have prepared these four berry extracts and examined whether they have anti-aging effects and if those effects correlate with their antioxidant activities.Methods: We studied the following effects of 4 berry extracts: 1) lens cell protective effects; 2) effects against alopecia; 3) induction of uncoupling protein-1 (UCP1), a regulator of fat and energy consumption in adipocytes, and stimulation of irisin secretion from skeletal muscle cells; and 4) inhibitory effects on melanocyte tyrosinase activity. The evaluation method was based on below; 1) a-crystallin, type 17 collagen, heat shock protein 47 (HSP47), UCP1 and Irisin - mRNA by qRT-PCR, 2) the amount of the UCP1 and Irisin protein by ELISA. 3) Inhibition of tyrosinase activity was measured by dopachrome production using L-tyrosine.Results: In lens cells, a-crystallin mRNA expression was induced 1 hour after treatment of the cell with Blabina (a powdered formulation containing BRE) and BRE. The extracts of all four berry species promoted the growth of follicle dermal papilla cells by 3-20% in a concentration-dependent manner. These berry extracts were also discovered to markedly induce the expression of mRNAs of type 17 collagen and HSP47 in the hair follicle stem cell and elevate the expression levels of UCP1 mRNA and its protein in adipocytes in a concentration-dependent manner. BRE and Blabina inhibited 5a-reductase in follicle dermal papilla cells and tyrosinase activity in melanocytes at the concentrations which inhibited dopachrome production by at least 50%. Finally, Blabina was discovered to stimulate the irisin secretion from skeletal muscles.Conclusion: These results suggest that berry extracts, particularly BRE, have anti-aging effects through their higher antioxidant activities.Keywords: Anti-aging; antioxidant; alopecia; black raspberry; weight loss; oxygen radical, absorbance capacity; skin whitening

Antioxidant Activity of Alcoholic Beverages Made From Various Cereal Grains Using Koji Made with Thai Amylomyces Rouxii YTH3 as Saccharifying Agent

Microbial starter called koji in Japanese was made with fungal strain Amylomyces rouxii YTH3 isolated from Thai microbial starter, loog pang. Koji made with A. rouxii YTH3 was applicable for saccharifying agent for ethanol fermentation. Novel alcoholic beverage was made from various cereal grains and this koji, and analyzed. Ethanol concentration, pH and acidity were 8.2 to 10.8% (v/v), 3.5 to 4.4 and 3.0 to 5.2 ml. An alcoholic beverage made from black rice (Oryza sativa var. Japonica cv. Shiun) having anthocyanin showed brilliant red color. An alcoholic beverage made from black rice showed rather a higher antioxidant activity comparing other alcoholic beverage. The DPPH radical scavenging activity of the alcoholic beverage made from black rice was around 1800 µM Trolox equivalent, while other alcoholic beverages were 300 to 600 µM Trolox equivalent.&#x0D; Keywords: Amylomyces rouxii, loog pang, black rice, alcoholic beverage, koji

Effects of thermal treatments on the colloidal properties, antioxidant capacity and in-vitro proteolytic degradation of cricket flour

Insects are gaining increased interest as rich, viable and sustainable sources of edible proteins. However, low consumer acceptance of insects as human food stimulates a need to mask the insects' appearance through various processing operations, such as grinding, cooking and baking. This research studied the implications of thermal processing of cricket (Acheta domesticus) flour on its physiochemical properties, antioxidant capacity and bioaccessibility in the gastrointestinal tract. Thermal processing led to marginal changes in colloid sizes and zeta-potentials at 3.0 < pH < 7.0. Concomitantly, sample color changes upon processing (delta E) were found to at least double when processed in the presence of fructose compared to processing without fructose (evaluated by L*a*b*color values). Overall, processed cricket flour changes were all ascribed to thermally-induced phenomena, such as protein denaturation, cross-linking, Maillard glycation and/or aggregation. Next, antioxidant activity examined by FRAP and ORAC assays revealed thermally-treated cricket flour had a significantly (p < 0.05) diminished electron transfer ability with a simultaneous rise in its proton abstraction capability exceeding 400 μM Trolox equivalents. This improved antioxidant activity may be attributed to conformational changes in cricket proteins exposing proton-donating residues, namely cysteine. Finally, dynamic in vitro digestion of untreated and treated cricket flours showed that baking increased the gastric proteolysis of cricket proteins and their subsequent bioaccessibility. Thus, justifying further investigation of industrial processes that could be harnessed to fabricate palatable and nourishing insect-based products.

Bioaccessibility of phenolic compounds following in vitro large intestine fermentation of nuts for human consumption

A bioaccessibility study of polyphenols after in vitro simulated large intestine fermentation was carried out on edible nuts. Raw nuts were also analysed for total phenolic content and antioxidant potential, considering both bound and free phenolics. The highest phenolic content was found in walnuts, followed by pistachios extracts (596.9 and 410.1 mg gallic acid equivalents 100 g−1, respectively). Consistently, the total antioxidant capacity was highest in walnuts (3689.7 μM trolox equivalents 100 g−1) followed by peanuts and pistachios (3169.6 and 2990.1 μM trolox equivalents 100 g−1, respectively). Data showed high correlations between total phenolics and both antioxidant activities. The metabolomics-based phenolic profile depicted during in vitro fermentation showed a degradation of higher-molecular-weight phenolics over 48 hours of faecal fermentation, with a concurrent increase in low-molecular-weight compounds (hydroxybenzoic and hydroxycinnamic acids, alkylphenols, and tyrosols). Our findings indicate that nuts deliver polyphenols into the colon, with bioaccessibility values not negligible for alkylphenols, tyrosols and phenolic acids.

Phytochemical Compositions of Immature Wheat Bran, and Its Antioxidant Capacity, Cell Growth Inhibition, and Apoptosis Induction through Tumor Suppressor Gene.

The purpose of this study was to investigate the phytochemical compositions and antioxidant capacity, cell growth inhibition, and apoptosis induction in extracts of immature wheat bran. Immature wheat bran (IWB) was obtained from immature wheat harvested 10 days earlier than mature wheat. The phytochemical compositions of bran extract samples were analyzed by ultra-high performance liquid chromatography. The total ferulic acid (3.09 mg/g) and p-coumaric acid (75 µg/g) in IWB were significantly higher than in mature wheat bran (MWB, ferulic acid: 1.79 mg/g; p-coumaric acid: 55 µg/g). The oxygen radical absorbance capacity (ORAC: 327 µM Trolox equivalents (TE)/g) and cellular antioxidant activity (CAA: 4.59 µM Quercetin equivalents (QE)/g) of the IWB were higher than those of the MWB (ORAC: 281 µM TE/g; CAA: 0.63 µM QE/g). When assessing cell proliferation, the IWB extracts resulted in the lowest EC50 values against HT-29 (18.9 mg/mL), Caco-2 (7.74 mg/mL), and HeLa cells (8.17 mg/mL) among bran extract samples. Additionally, the IWB extracts increased the gene expression of p53 and PTEN (tumor suppressor genes) in HT-29 cells, indicating inhibited cell growth and induced apoptosis through tumor suppressor genes.

Variation in phenolic compounds and antioxidant activity in apple seeds of seven cultivars

Polyphenols are the predominant ingredients in apple seeds. However, few data are available on the phenolic profile or antioxidant activity in apple seeds in previous researches. In this study, low-molecular-weight phenolic compounds and antioxidant activity in seeds, peels, and flesh of seven apple cultivars grown in northwest China were measured and analyzed using HPLC and FRAP, DPPH, ABTS assays, respectively. HPLC analysis revealed phloridzin as the dominant phenolic compound in the seeds with its contents being 240.45–864.42mg/100gDW. Total phenolic content (TPC) measured by the Folin–Ciocalteu assay in apple seed extracts of seven cultivars ranged from 5.74 (Golden Delicious) to 17.44 (Honeycrisp)mgGAE/gDW. Apple seeds showed higher antioxidant activity than peels or flesh; antioxidant activity in seeds varied from 57.59 to 397.70μM Trolox equivalents (TE)/g FW for FRAP, from 37.56 to 64.31μM TE/g FW for DPPH, and from 220.52 to 708.02μM TE/g FW for ABTS. TPC in apple seeds was significantly correlated with all three assays. Principal component analysis (PCA) indicated that Honeycrisp was characterized with high contents of total polyphenols and phloridzin. Our findings suggest that phenolic extracts from apple seeds have good commercial potential as a promising antioxidant for use in food or cosmetics.