60Co-γ Radiation Alters Developmental Stages of Zeugodacus cucurbitae (Diptera: Tephritidae) Through Apoptosis Pathways Gene Expression.

Radiation is considered as a promising insect pest control strategy for minimizing postharvest yield losses. Among various techniques, irradiation is a method of choice as it induces lethal biochemical or molecular changes that cause a downstream cascade of abrupt physiological abnormalities at the cellular level. In this study, we evaluated the effect of 60Co-γ radiation on various developmental stages of Zeugodacus cucurbitae Coquillett and subsequent carry-over effects on the progeny. For this purpose, we treated eggs with 30- and 50-Gy radiation doses of 60Co-γ. We found that radiation significantly affected cellular antioxidants, insect morphology, and gene expression profiles. Our results indicate that in response to various doses of irradiation reactive oxygen species, catalase, peroxidase, and superoxide dismutase activities were increased along with a significant increase in the malondialdehyde (MDA) content. We observed higher mortality rates during the pupal stage of the insects that hatched from irradiated eggs (50 Gy). Furthermore, the life span of the adults was reduced in response to 50 Gy radiation. The negative effects carried over to the next generation were marked by significantly lower fecundity in the F1 generation of the irradiation groups as compared to control. The radiation induced morphological abnormalities at the pupal, as well as the adult, stages. Furthermore, variations in the gene expression following irradiation are discussed. Taken together, our results signify the utility of 60Co-γ radiation for fruit fly postharvest management.

The effect of computed tomography on oxidative stress level and some antioxidant parameters.

BACKGROUND: X-rays are defined as ionizing radiation and hydrolyze the water, causing free radical formation. Oxidative stress is the damage that occurs in cells due to the lack of antioxidants, which detoxifies them, with the increased production of free radicals that occur during normal cellular metabolism. PURPOSE: To examine the acute effects of computed tomography (CT), i.e. ionizing radiation, on oxidative stress and antioxidant defense mechanisms. MATERIAL AND METHODS: The study included a total of 53 patients that were selected among the patients that underwent non-contrast full-body CT. Malondialdehyde (MDA) and reduced glutathione (GSH) levels and superoxide dismutase (SOD) and catalase (CAT) activities were investigated in blood samples taken from patients. RESULTS: The post-scan levels of MDA increased significantly while the post-scan levels of GSH, SOD, and CAT decreased significantly compared to their pre-scan levels. CONCLUSION: CT, which is a widely used X-ray imaging technique and has numerous known side effects, was found to increase the levels of MDA, which is an indicator of oxidative stress, and to decrease the levels of some antioxidants including GSH, SOD, and CAT.

Molecular and Biochemical Basis of Fluoroquinolones-Induced Phototoxicity-The Study of Antioxidant System in Human Melanocytes Exposed to UV-A Radiation.

Phototoxicity of fluoroquinolones is connected with oxidative stress induction. Lomefloxacin (8-halogenated derivative) is considered the most phototoxic fluoroquinolone and moxifloxacin (8-methoxy derivative) the least. Melanin pigment may protect cells from oxidative damage. On the other hand, fluoroquinolone-melanin binding may lead to accumulation of drugs and increase their toxicity to skin. The study aimed to examine the antioxidant defense system status in normal melanocytes treated with lomefloxacin and moxifloxacin and exposed to UV-A radiation. The obtained results demonstrated that UV-A radiation enhanced only the lomefloxacin-induced cytotoxic effect in tested cells. It was found that fluoroquinolones alone and with UV-A radiation decreased superoxide dismutase (SOD) activity and SOD1 expression. UV-A radiation enhanced the impact of moxifloxacin on hydrogen peroxide-scavenging enzymes. In turn, lomefloxacin alone increased the activity and the expression of catalase (CAT) and glutathione peroxidase (GPx), whereas UV-A radiation significantly modified the effects of drugs on these enzymes. Taken together, both analyzed fluoroquinolones induced oxidative stress in melanocytes, however, the molecular and biochemical studies indicated the miscellaneous mechanisms for the tested drugs. The variability in phototoxic potential between lomefloxacin and moxifloxacin may result from different effects on the antioxidant enzymes.

Ultrasound Treatment of Buckwheat Grains Impacts Important Functional Properties of Resulting Flour.

The benefit of not containing the gluten complex protein also provides problems with the achievement of typical and proper texture, especially in bakery products. Ultrasound (US) treatment has been previously studied on buckwheat as assistance treatment facilitating the release of antioxidant compounds. However, there is no study regarding the changes occurring in US-treated buckwheat grains regarding the structure-creating capacity, like water absorption, gelling, and pasting. The aim of this study is to the impact of US-treatment of buckwheat grains at 1:10, 1:5, and 1:2.5 solid: liquid ratio (in water). The particle size distribution, water absorption index (WAI), water solubility index (WSI), swelling power (SP), pasting characteristics, color, soluble, insoluble and total polyphenols content (SPC, IPC, TPC) and antioxidant activity (DPPH) were assessed in resulting flours. US-treatment caused specific agglomeration, resulting in bigger particles for 1:5, and 1:2.5 ratio treated samples, while higher dilution (1:10) increased smaller particle size fractions. The WAI and SP were the highest for the1:5 solid: liquid ratio sample, and the same sample revealed the highest peak viscosity, breakdown, and setback values. The ultrasound treatment increased the WSI, which was positively correlated with insoluble polyphenols content. The soluble polyphenols content decreased, and insoluble polyphenols content increased in all ultrasound treated samples. The DPPH scavenging activity remaining in grain after US treatment was lowered compared to the control sample. The relocation of pigments resulted in a redness and yellowish increase in all treated samples, while lightness was also increased but was most pronounced for a 1:10 ratio treated sample. The results suggest that ultrasound treatment of grain can improve the essential functional properties of buckwheat flour.

Exploring Ultrasound, Microwave and Ultrasound-Microwave Assisted Extraction Technologies to Increase the Extraction of Bioactive Compounds and Antioxidants from Brown Macroalgae.

This study aims to determine the influence of (1) ultrasound-assisted extraction (UAE), (2) microwave-assisted extraction (MAE) and (3) a combination of ultrasound-microwave-assisted extraction (UMAE) on the yields of fucose-sulphated polysaccharides (FSPs), total soluble carbohydrates and antioxidants extracted from A. nodosum. Scanning electron microscopy (SEM) was used to evaluate the influence of the extraction technologies on the surface of macroalgae while principal component analysis was used to assess the influence of the extraction forces on the yields of compounds. UMAE generated higher yields of compounds compared to UAE and MAE methods separately. The maximum yields of compounds achieved using UMAE were: FSPs (3533.75 ± 55.81 mg fucose/100 g dried macroalgae (dm)), total soluble carbohydrates (10408.72 ± 229.11 mg glucose equivalents/100 g dm) and phenolic compounds (2605.89 ± 192.97 mg gallic acid equivalents/100 g dm). The antioxidant properties of the extracts showed no clear trend or extreme improvements by using UAE, MAE or UMAE. The macroalgal cells were strongly altered by the application of MAE and UMAE, as revealed by the SEM images. Further research will be needed to understand the combined effect of sono-generated and microwave-induced modifications on macroalgae that will allow us to tailor the forces of extraction to target specific molecules.

Antioxidant status and cytogenetic damage in hospital workers occupationally exposed to low dose ionizing radiation.

The aim of the present study was to assess the oxidative stress level and chromosomal damage induced by occupational exposure to low dose ionizing radiation (LDIR). Two hundred and eighteen hospital workers occupationally exposed to LDIR were included in this study, along with 118 healthy age- and gender-comparable controls. Occupational dosimetry records were collected over the last year and revealed that the accumulated annual dose for each hospital worker was below the permissible limit of the International Commission on Radiological Protection (ICRP). The individuals' oxidative and antioxidative status were determined by measuring the activities of copper zinc-superoxide dismutase (CuZn-SOD), glutathione peroxidase (GSH-Px), catalase (CAT) enzymes, and the levels of malondialdehyde (MDA) in erythrocytes. The effect of radiation on chromosomal integrity was measured by the frequency of micronuclei (MN) formation using the cytokinesis block technique. Our results showed that the activities of CuZn-SOD and CAT enzymes and MDA levels observed in the hospital workers were higher than those in the controls (p < 0.05). We did not find significant difference in GSH-Px enzyme activity between the two groups (p = 0.247). A higher frequency of MN was found in exposed groups than in the controls [3(1-5) ‰ versus 2(0.75-4) ‰; p<0.001]. The difference was significant for males (p = 0.012), but not females (p = 0.14). Multiple linear regression analysis showed differences in the oxidant activities and MN frequency between hospital workers and controls adjusted for age, gender, smoking status and drinking status. Correlation analysis indicated that the frequency of MN was positively associated with MDA levels (p < 0.05). Altogether, these results support the detrimental effects of chronic low dose radiation in humans, which involves the induction of oxidative stress and chromosomal damage.

Effect of Infrared Low-Intensity Laser Irradiation on Lipid Peroxidation under Conditions of Experimental Circulatory Hypoxia of Visual Analyzer.

The physiological stress modeled by circulatory hypoxia activates LPO processes in various tissues. In posthypoxic period, the infrared low-intensity laser irradiation significantly decreased the chemiluminescence parameters in blood plasma, normalized the retinal levels of diene and triene conjugates, and decreased MDA in the rat brain attesting to the correcting effect of this irradiation during various types of physiological stresses.

Prevention of UVB radiation-induced oxidative stress in mice by topical administration of Azadirachta indica(neem) extract

Neem tree (Azadirachta indica A. Juss. fam. Meliaceae) has been extensively employed to combat diverse pathologies. Moreover, it has been described that its leaf extract present anticarcinogenic action. Thus, the neem extract (NE) chemical and antioxidant properties was evaluated, and also, the capacity of two dermatological formulations incorporated with neem extract (F1 and F2) to avoid oxidative UVB-induced skin injury in hairless mice. NE constituents were investigated and free radical scavenging ability were determined by different methods in vitro. Skin from mice treated with F1 and F2 and submitted to UVB radiation were tested for different parameters of inflammation and oxidative injury. Results show that the NE polyphenol and flavonoid content were 135.30 and 37.12mg/g, respectively. High performance liquid chromatography (HPLC) results demonstrated the existence of azarachtin, rutin, ursolic acid and tannic acid. NE presented scavenging ability by ABTS radical, ferric-reducing antioxidant power (FRAP), inhibition of lipid peroxidation and iron chelation. In vivo, it was observed that mice treated with F1 and F2 showed amelioration of the inflammation by reducing UVB induced skin edema. However, only samples from animals treated with F1 had lower neutrophil recruitment (measured by myeloperoxidase activity), and returning the oxidative status to baseline levels in parameters such as reduced glutathione level, ferric reducing ability (FRAP), and scavenging of free radical (ABTS). Concluding, NE demonstrated a good antioxidant property in vitro, and the data suggest the use of NE added F1 to prevent skin damage caused by UVB irradiation.(AU)

Effect of microwave radiation on the antioxidant activity of black cumin seed.

BACKGROUND: Black cumin seed contains considerable amounts of bioactive phenolics that have physiological activity and antioxidant potency, which may be boosted by microwave radiation. The core objective of the study was to evaluate the influence of microwave radiation on the antioxidant activity of cumin seed as a function of pretreatment time and extract concentration. METHODS: In this study, total flavonoid content (TFC) and antioxidant activity of methanol (CME), 70% methanol in water (CMW), ethanol (CEE) and 70% ethanol in water (CEW) extracts of microwaved radiated cumin seed were measured. The antioxidant activity was determined using a Folin-Ciocalteu assay, phosphomolybdenum assay, DPPH radical scavenging activity, H2O2 scavenging activity, hydroxyl radical scavenging activity and reducing power. To predict antioxidant potency, FTIR spectra of extracts were also recorded. RESULTS: Microwave pretreatment significantly reduced the TFC with the pretreatment time. Antioxidant activity increased with increasing pretreatment time and extract concentration in all extracts. Aqueous methanolic extract from radiated seeds appeared to display the highest effectiveness. The results from FT-IR of ex- tracts indicating the existence of multiple functional groups were comparable to those obtained from multiple antioxidative assays. The antioxidant effectiveness of the samples was ranked: CMW > CEW > CME > CEE. CONCLUSIONS: Both treatment duration and extract concentration were found to be critical factors in determin- ing the overall quality of the product. The present study revealed important information for using black cumin seed in developing food products with high antioxidant potency.

One pot synthesis of water-soluble quercetin derived multifunctional nanoparticles with photothermal and antioxidation capabilities.

As a member of flavonoids, the application of quercetin has been mainly focused on antioxidation study. Fabrication of multifunctional nanoplatforms with quercetin is limited. In the present study, water-soluble quercetin derived nanoparticles (QFNPs) were fabricated through the one pot synthesis strategy with Fe3+, quercetin and poly (vinyl pyrrolidone) (PVP). The raw materials were dissolved in absolute ethanol and the mixed together. After stirring at room temperature for 6 h, the QFNPs could be simply harvested by centrifugation without the need of time-consuming dialysis procedure. Due to the protective effect of PVP, the synthesized nanoparticles could be well dispersed in water with the hydrodynamic size about 23 nm. DPPH free radical scavenging capacity assay showed QFNPs could act as efficient antioxidant. Besides antioxidation activity, the QFNPs also exhibited good photothermal capacity. Temperature stability result suggested the good stability of QFNPs between 35 and 95 °C. MTT and hemolysis assay showed the good biocompatibility of QFNPs. What's more, the QFNPs showed good cellular antioxidation activity and efficient photothermal killing effect to cancer cells (4T1 cells). The QFNPs could be promising nanoplatform for biomedical application.

Radioprotective Effect of Hesperidin: A Systematic Review.

Background and objectives: Ionizing radiation (IR) has been of immense benefit to man, especially for medical purposes (diagnostic imaging and radiotherapy). However, the risks of toxicity in healthy normal cells, leading to cellular damage as well as early and late side effects, have been major drawbacks. The aim of this study was to evaluate the radioprotective effect of hesperidin against IR-induced damage. Materials and Methods: The preferred reporting items for systematic reviews and meta-analyses (PRISMA) were applied in reporting this study. A search was conducted using the electronic databases PubMed, Scopus, Embase, Google Scholar, and www.ClinicalTrials.gov for information about completed or ongoing clinical trials. Results: From our search results, 24 studies involving rats, mice, and cultured human and animal cells were included. An experimental case-control design was used in all studies. The studies showed that the administration of hesperidin reduced oxidative stress and inflammation in all investigated tissues. Furthermore, it increased 30-day and 60-day survival rates and protected against DNA damage. The best radioprotection was obtained when hesperidin was administered before irradiation. Conclusions: The results of the included studies support the antioxidant, anti-inflammatory, and antiapoptotic abilities of hesperidin as a potential radioprotective agent against IR-induced damage. We recommend future clinical trials for more insights.

Intracellular antioxidant activity and apoptosis inhibition capacity of PEF-treated KDHCH in HepG2 cells.

The effect of pulsed electric field (PEF) treatment on the intracellular antioxidant and apoptotic activity of the peptide Lys-Asp-His-Cys-His (KDHCH) was examined using model HepG2 cells. First, PEF treatment conditions specific for the antioxidant peptide were optimized, and it was found that PEF treatment could enhance DPPH, ABTS and hydroxyl radical scavenging capacity of KDHCH. Second, KDHCH subjected to PEF treatment at 1800 Hz and 15 kV/cm was investigated using various intracellular antioxidant assays. PEF treatment decreased the EC50 value and increased the protective ability of oxidative stress inhibition and reactive oxygen species (ROS) scavenging activity of KDHCH. Furthermore, catalase (CAT), superoxide dismutase (SOD), glutathione peroxidase (GSH-PX) and glutathione reductase (GR) activities of KDHCH-pre-treated HepG2 cells increased significantly compared with those of the H2O2 damaged group, whereas lactate dehydrogenase (LDH) and malonaldehyde (MDA) content were decreased. PEF-treated KDHCH exhibited an increased capacity to maintain the stability of mitochondrial membrane potential (MMP) and reduced the level of caspase-3. These results indicate that PEF treatment can enhance the intracellular antioxidant activity of KDHCH, which can inhibit the effect of H2O2 oxidation on HepG2 cells by inhibiting the accumulation of intracellular ROS, regulating antioxidant related enzymes, and blocking the apoptotic mitochondrial pathways activated by ROS.

Plant morphology, physiological characteristics, accumulation of secondary metabolites and antioxidant activities of Prunella vulgaris L. under UV solar exclusion

BACKGROUND: Prunella vulgaris L. has been an important medicinal plant for the treatment of thyroid gland malfunction and mastitis in China for over 2000 years. There is an urgent need to select effective wavelengths for greenhouse cultivation of P. vulgaris as light is a very important factor in P. vulgaris growth. Here, we described the effects of natural light (control) and UV solar exclusion on the morphological and physiological traits, secondary metabolites contents and antioxidant activities of P. vulgaris. RESULTS: The results showed that UV solar exclusion resulted in remarkable alterations to morphological and biomass traits; significantly reduced the chlorophyll a, chlorophyll b and total chlorophyll contents; significantly enhanced the ratio of chlorophyll a to b; and significantly increased the carotenoid and anthocyanin contents in P. vulgaris. UV solar exclusion significantly increased the catalase (CAT) and peroxidase (POD) activities, increased superoxide dismutase (SOD) and ascorbate peroxidase (APX) activities and slightly decreased the glutathione (GSH) content. UV solar exclusion significantly increased the soluble sugar and H2O2 contents and increased the soluble protein content but significantly decreased the proline content and slightly decreased the MDA content. The secondary metabolite contents (total phenolics, rosmarinic acid, caffeic acid, hyperoside, ursolic acid and oleanolic acid) and in vitro antioxidative properties (DPPH· and ABTS·+scavenging activities) were significantly increased in P. vulgaris spicas under UV solar exclusion. Additionally, the total polysaccharide and total flavonoids contents were slightly increased by UV solar exclusion. The salviaflaside content was significantly reduced by UV solar exclusion. CONCLUSION: Our study demonstrated that P. vulgaris activates several antioxidant defence systems against oxidative damage caused by UV solar exclusion.

Dragon's Blood Sap: Storage Stability and Antioxidant Activity.

Currently, consumers are demanding additive-free, fresher, and more-natural products. Dragon's Blood Sap (DBS), the deep red latex of the specie of tree Croton lechleri (Müll. Arg.), contains a high concentration of phenolic compounds of great interest for the food, pharmaceutical, and cosmetic industries. These chemical compounds are highly susceptible to degradation. Therefore, DBS storage stability and its photo-oxidation was studied by Fourier transform infrared spectroscopy (FT-IR) and UV-Vis spectrophotometry for 39 days at different temperatures (4⁻21 °C) and relative humidities (0⁻56%), as well as under UV light exposure. It was observed that the degradation of phenolic compounds was reduced at 0% relative humidity (RH), not showing a significant effect of temperature in the range studied. UV light irradiation degraded DBS in a 20%. DBS has an exceptional high and stable antioxidant content (≥93% inhibition percentage of DPPH), which makes it a unique property to consider the DBS as an antioxidant agent or ingredient for consumer products formulations.

Effects of 200 Gy 60Co-γ Radiation on the Regulation of Antioxidant Enzymes, Hsp70 Genes, and Serum Molecules of Plutella xylostella (Linnaeus).

The diamondback moth, Plutella xylostella (Linnaeus), is one of the notorious pests causing substantial loses to many cruciferous vegetables across the nations. The effects of 60Co-γ radiation on physiology of P. xylostella were investigated and the results displayed that 200 Gy irradiation significantly alters the antioxidant enzyme regulation in six-day-old male pupae of P. xylostella. First, in our research, we detected Oxidase system and stress response mechanism of irradiated pupae, the results displayed that 200 Gy irradiation significantly alters the antioxidant enzyme regulation in six-day-old male pupae of P. xylostella. The levels of superoxide dismutase (SOD) and catalase (CAT) were increased significantly in contrast the level of peroxidase (POD) and glutathione S-transferase (GST) were decreased in 12⁻24 h post-treatment. The heat shock proteins (Hsps) gene expression level was significant increasing, maximum > 2-folds upregulation of genes were observed in peak. However, they also had a trend of gradual recovery with development. Second, we detected the testis lactate dehydrogenase (LDH) and acid phosphatase (ACP) activity found that in male adults testis they increased significantly than control during its development. Thus the present research investigation highlights that the 60Co-γ radiation treatments alters the physiological development of diamondback moth. The results showed that 200 Gy dosage resulted in stress damage to the body and reproductive system of the diamondback moth.

Comparison of Conventional and Microwave Assisted Heating on Carbohydrate Content, Antioxidant Capacity and Postprandial Glycemic Response in Oat Meals.

Minimally processed cereal breakfast products from whole grain entered the market due to consumer demand of more nutritional food with more controlled sugar release. However, the subsequent processing of such products with different cooking methods in the consumer's kitchen may lead to significant differentiation of their nutritional value. Therefore, the evaluation of the impact of frequently used cooking methods on a final quality of breakfast cereals meal is needed. The present study investigates how the two different methods of heating, conventional and microwave (MW) assisted, affect the carbohydrate content, profile and resulting glycemic index of so prepared food as well as the antioxidant activity of meals. Two products available on the market-oat bran and flakes-were used. The highest starch content in fluid phase of oatmeal was detected in samples heated for 3 min with microwaves, regardless the type. The lowest starch content was obtained for 5 min MW heated flakes sample. The total content of glucose was about 1.5 times lower in bran vs. flakes oatmeal. The highest ß-glucan content in fluid fraction was also observed for bran meal but its release was independent of applied conditions.

Optimization of enzymes-microwave-ultrasound assisted extraction of Lentinus edodes polysaccharides and determination of its antioxidant activity.

Enzymes-microwave-ultrasound assisted extraction (EMUE) method had been used to extract Lentinus edodes polysaccharides (LEPs). The enzymatic temperature, enzymatic pH, microwave power and microwave time were optimized by response surface methodology. The yields, properties and antioxidant activities of LEPs from EMUE and other extraction methods including hot-water extraction, enzymes-assisted extraction, microwave-assisted extraction and ultrasound-assisted extraction were evaluated. The results showed that the highest LEPs yield of 9.38% was achieved with enzymatic temperature of 48°C, enzymatic pH of 5.0, microwave power of 440W and microwave time of 10min, which correlated well with the predicted value of 9.79%. Additionally, LEPs from different extraction methods possessed typical absorption peak of polysaccharides, which meant different extraction methods had no significant effects on type of glycosidic bonds and sugar ring of LEPs. However, SEM images of LEPs from different extraction methods were significantly different. Moreover, the different LEPs all showed antioxidant activities, but LEPs from EMUE showed the highest reducing power when compared to other LEPs. The results indicated LEPs from EMUE can be used as natural antioxidant component in the pharmaceutical and functional food industries.

Antimicrobial, antioxidant and anticancer activities of zinc nanoparticles prepared by natural polysaccharides and gamma radiation.

Aqueous dispersed zinc nanoparticles (ZnNPs) were synthesized using natural polysaccherides (chitosan (CS), citrus pectin (CP) and alginate (Alg)) using aqueous fermented fenugreek powder (FFP) by Pleurotus ostreatus as reducing and stabilizing agent or using gamma irradiation. The synthesized ZnNPs are characterized by ultra violect spectroscopy (UV), Transmission electronmicroscopy (TEM), Dynamic light scattering (DLS), X-ray diffraction (XRD), and Fourier transform infrared spectroscopy (FT-IR). XRD analysis of the ZnNPS confirmed the formation of metallic nanoparticles. The nucleation and growth mechanism of ZnNPs is also discussed. TEM showed that the average diameter of ZnNPs was in the range of 46nm. The size of nanoparticles is influenced by certain parameters such as the choice of stabilizer, pH during synthesis and absorbed dose. Evaluating the antioxidant and anticancer activities of ZnNPs was performed. The results indicating the ZnNPs synthesized by aqueous fermented fenugreek extract have high activity and the average size is 46nm. The results explored that ZnNPs show anticancer activity against Ehrlich Ascites Carcinoma (EAC) and human colon adenocarcinoma (CACO) and the IC50% was 47.5µg/ml and 65µg/ml respectively. Also, ZnNPs had excellent bactericidal activity against gram positive and negative bacteria and yeast.

Effect of Pulsed Light Irradiation on Bioactive, Nonvolatile Components and Antioxidant Properties of Caterpillar Medicinal Mushroom Cordyceps militaris (Ascomycetes).

The caterpillar medicinal mushroom Cordyceps militaris contains many bioactive components, such as adenosine, cordycepin, and polysaccharides. In this study, C. militaris was exposed to 0, 3, 6, or 9 pulses of light irradiation to estimate changes in vitamin D2, bioactive compounds, nonvolatile taste components, and antioxidant properties. In addition, we compared the components and properties of C. militaris mycelia and solid waste medium that had been treated with pulsed light (PL) irradiation. Overall, PL irradiation of C. militaris increased the vitamin D2 content and increased the total amino acid levels 9-48%; the antioxidant properties of the mycelia treated with 0 pulses and of the solid waste medium treated with 3 pulses all exhibited lower half-maximal effective concentrations. Therefore, PL irradiation affected the amounts of bioactive compounds, but the irradiated samples still contained intense umami taste and a sufficient amount of antioxidant components.

Effect of cooking and in vitro digestion on the antioxidant activity of dry-cured ham by-products.

Dry-cured ham by-products have been traditionally used in Mediterranean household cooking of broths and stews. The aim of this work was to evaluate the effect of cooking treatments and in vitro gastrointestinal digestion on the antioxidant activity of natural peptides found in bones from Spanish dry-cured hams. The antioxidant activity was tested using five different assays and results demonstrated that cooking using conventional household methods increased the antioxidant activity of ham by-products when assessed using different antioxidant assays with the exception of the ABTS radical scavenging measurement assay. Simulated gastrointestinal digestion showed no significant effect on the antioxidant activity of ham by-products and antioxidant activity decreased when assessed using the ORAC and ß-carotene bleaching assays. Analysis by MALDI-TOF MS revealed a considerable breakdown of peptides due to the action of gastrointestinal enzymes, mainly in samples cooked at 100°C for 1h. In addition, 459 peptides derived from 57 proteins were identified and quantified using mass spectrometry in tandem, evidencing that peptides derived from collagen protein were responsible for the differences in antioxidant activities observed between the uncooked and cooked samples after digestion. The results show the potential of dry-cured ham bones as a source of antioxidant peptides that retain their bioactivity after household cooking preparations and gastrointestinal digestion.