Search Results (11)

Vegetables are usually thermally processed before consumption to improve their flavor and safety. In this work, the effect of boiling (BO), blanching (BL), steaming (ST), air-frying (AF), and pan-frying (PF)on the nutritional value and bioactivity of broccoli (Brassica oleracea var. italica) heads was investigated, including a comparative analysis of the tissue and the cooking water remaining after the treatments. Using spectrophotometric methods, AF broccoli was found to have the highest levels (p ≤ 0.05) of hydroxycinnamic acids (1.58 ± 0.71 mg CAE/g fw), total glucosinolates (3.76 ± 2.09 mg SinE/g fw), carotenoids (6.73 ± 2.89 mg/kg fw), and lycopene (0.91 ± 0.19 mg/kg fw). Steamed and AF broccoli had the highest total phenolics (0.72 ± 0.12 mg GAE/g fw and 0.65 ± 0.15 mg GAE/g fw, respectively; p ≤ 0.05). ST broccoli also had the highest levels of soluble sugars (11.04 ± 2.45 mg SucE/g fw) and total tannins (0.46 ± 0.19 mg GAE/g fw). The water remaining after cooking broccoli (BOW) had the highest total flavonoids (2.72 ± 0.59 mg QE/g fw) and antioxidant capacity (ABTS and FRAP, 57.57 ± 18.22% and 79.34 ± 3.28%, respectively; p ≤ 0.05). The DPPH assay showed that AF (36.12 ± 15.71%) and ST (35.48 ± 2.28%) had the strongest antioxidant potential. DNA nicking assay showed that BOW and BLW were the most effective in preserving plasmid DNA supercoiled form (99.51% and 94.81%, respectively; p ≤ 0.05). These results demonstrate that thermal processing significantly affects the phytochemical composition and functional properties of broccoli, with steaming and air-frying generally preserving the highest nutritional quality. Additionally, cooking water, often discarded, retains high levels of bioactive compounds and exhibits strong antioxidant and DNA-protective effects. To the best of our knowledge, this is the first study to investigate how different thermal processing techniques of vegetables influence their ability to protect plasmid DNA structure. Furthermore, this is the first study to compare the DNA-protective effects of broccoli tissue extracts and the water remaining after cooking broccoli. Full article

Phosphorus (P) and silicon (Si) could profoundly affect the net primary productivity (ANPP) of grassland ecosystems. However, how ecosystem biomass will respond to different Si addition, especially under a concurrent increase in P fertilization, remains limited. With persistent demand for grassland utilization, there is a need to enhance and sustain the productivity of grasslands on the Qinghai–Tibet Plateau. Three P addition rates (0, 400, 800, and 1200 kg Ca(H₂PO₄)₂ ha⁻¹ yr⁻¹) without Si and with Si (14.36 kg H₄SiO₄ ha⁻¹ yr⁻¹) were applied to alpine grassland on the Qinghai–Tibet Plateau to evaluate the responses of aboveground biomass and the underlying mechanisms linking to structural carbon composition and physiological traits of grasses and forbs. Our results show that the application of Si significantly reduced the lignin, cellulose, hemicellulose, and total phenol contents of both grasses and forbs. Additionally, the addition of P, Si, and phosphorus and silicon (PSi) co-application significantly increased the net photosynthetic rate (Pn) and light use efficiency (LUE) of grasses and forbs. Moreover, Si promoted the absorption of N and P by plants, resulting in significant changes in the Si:C, Si:P, and Si:N ratios and increasing the aboveground biomass. Our findings suggest that Si can replace structural carbohydrates and regulate the absorption and utilization of N and P to optimize the photosynthetic process of leaves, thereby achieving greater biomass. In summary, Si supplementation improves ecosystem stability in alpine meadows by optimizing plant functions and increasing biomass accumulation. Full article

The aim of this study was to compare the concentration of phenolic compounds, glucosinolates, proteins, sugars and vitamin C between kohlrabi (Brassica oleracea var. acephala gongylodes), Savoy cabbage (B. oleracea sabauda), Brussels sprouts (B. oleracea gemmifera), cauliflower (B. oleracea botrytis), radish (Raphanus sativus) and garden cress (Lepidium sativum) microgreens for their antioxidant and hypoglycemic potential. In addition, we applied an in vitro-simulated system of human digestion in order to track the bioaccessibility of the selected phenolic representatives, and the stability of the microgreens’ antioxidant and hypoglycemic potential in terms of α-amylase and α-glucosidase inhibition after each digestion phase. Using spectrophotometric and RP-HPLC methods with statistical analyses, we found that garden cress had the lowest soluble sugar content, while Savoy cabbage and Brussels sprouts had the highest glucosinolate levels (76.21 ± 4.17 mg SinE/g dm and 77.73 ± 3.33 mg SinE/g dm, respectively). Brussels sprouts were the most effective at inhibiting protein glycation (37.98 ± 2.30% inhibition). A very high positive correlation (r = 0.830) between antiglycation potential and conjugated sinapic acid was recorded. For the first time, the antidiabetic potential of microgreens after in vitro digestion was studied. Kohlrabi microgreens best inhibited α-amylase in both initial and intestinal digestion (60.51 ± 3.65% inhibition and 62.96 ± 3.39% inhibition, respectively), and also showed the strongest inhibition of α-glucosidase post-digestion (19.22 ± 0.08% inhibition). Brussels sprouts, cauliflower, and radish had less stable α-glucosidase than α-amylase inhibitors during digestion. Kohlrabi, Savoy cabbage, and garden cress retained inhibition of both enzymes after digestion. Kohlrabi antioxidant capacity remained unchanged after digestion. The greatest variability was seen in the original samples, while the intestinal phase resulted in the most convergence, indicating that digestion reduced differences between the samples. In conclusion, this study highlights the potential of various microgreens as sources of bioactive compounds with antidiabetic and antiglycation properties. Notably, kohlrabi microgreens demonstrated significant enzyme inhibition after digestion, suggesting their promise in managing carbohydrate metabolism and supporting metabolic health. Full article

Few sclerophyllous plants from the central coast of Chile have been systematically studied. This work describes the phytochemical composition and antimicrobial properties of Baccharis concava Pers. (sin. B. macraei), a shrub found in the first line and near the Pacific coast. B. concava has been traditionally used by indigenous inhabitants of today’s central Chile for its medicinal properties. Few reports exist regarding the phytochemistry characterization and biological activities of B. concava. A hydroalcoholic extract of B. concava was prepared from leaves and small branches. Qualitative phytochemical characterization indicated the presence of alkaloids, steroids, terpenoids, flavonoids, phenolic, and tannin compounds. The antimicrobial activity of this extract was assessed in a panel of microorganisms including Gram-positive bacteria, Gram-negative bacteria, and pathogenic yeasts. The extract displayed an important antimicrobial effect against Gram-positive bacteria, Candida albicans, and Cryptococcus neoformans but not against Gram-negatives, for which an intact Lipopolysaccharide is apparently the determinant of resistance to B. concava extracts. The hydroalcoholic extract was then fractionated through a Sephadex LH-20/methanol–ethyl acetate column. Afterward, the fractions were pooled according to a similar pattern visualized by TLC/UV analysis. Fractions obtained by this criterion were assessed for their antimicrobial activity against Staphylococcus aureus. The fraction presenting the most antimicrobial activity was HPLC-ESI-MS/MS, obtaining molecules related to caffeoylquinic acid, dicaffeoylquinic acid, and quercetin, among others. In conclusion, the extracts of B. concava showed strong antimicrobial activity, probably due to the presence of metabolites derived from phenolic acids, such as caffeoylquinic acid, and flavonoids, such as quercetin, which in turn could be responsible for helping with wound healing. In addition, the development of antimicrobial therapies based on the molecules found in B. concava could help to combat infection caused by pathogenic yeasts and Gram-positive bacteria, without affecting the Gram-negative microbiota. Full article

The post-heat mechanical property is one of the important indices for the fire-resistance evaluation of fiber-reinforced polymers. At present, the primary approach to improving the post-heat mechanical property of a material involves incorporating inorganic fillers; yet, the enhancement is limited, and is accompanied by a reduction in room-temperature performance and processability. This study prepares glass-fiber-reinforced composites with elevated mechanical properties after heat through utilizing two variants of epoxy resins modified with polysiloxane, phenolic resin, kaolin, and graphite. In comparison to the phenolic samples, the phenylpropylsiloxane-modified epoxy resulted in a 115% rise in post-heat flexural strength and a 70% increase in the room-temperature flexural strength of phenolic composites. On the other hand, dimethylsiloxane-modified epoxy leads to a 117% improvement in post-heat flexural strength but a 44% decrease in the room-temperature flexural strength of phenolic composites. Macroscopic/microscopic morphologies and a residual structure model of the composites after heat reveal that, during high temperature exposure, the pyrolysis products of polysiloxane promote interactions between carbon elements and fillers, thus preserving more residues and improving the dimensional stability as well as the density of materials. Consequently, a notable enhancement is observed in both the post-heat flexural strength and the mass of carbon residue after the incorporation of polysiloxane and fillers into the materials. The pyrolysis products of polysiloxane-modified epoxy play a vital role in enhancing the post-heat flexural strength by promoting carbon retention, carbon fixation, and interactions with fillers, offering novel pathways for the development of advanced composites with superior fire-resistance properties. Full article

Barley (Hordeum vulgare L.) is the fourth largest cereal crop in the world. One of the most devastating diseases in barley worldwide is Fusarium head blight (FHB) caused by Fusarium graminearum Schwabe. Several mycotoxins are produced by FHB infection, and deoxynivalenol (DON) is one of them responsible for the deterioration of grain quality. The current limited number of reliable molecular markers makes the development of FHB-resistant cultivars rather difficult and laborious. Moreover, there is a limited number of designed specific biomarkers that could distinguish the FHB resistance and mycotoxin accumulation in barley cultivars. This study investigated the phenolic compounds of ten different Canadian barley cultivars, grown in artificially FHB-infected and non-infected field trials. The enzyme-linked immunosorbent assay (ELISA) was used to assess the presence of DON in the harvested infected grains of each tested variety. High-performance liquid chromatography (HPLC) analysis was performed using both infected and non-infected samples. We identified differences among cultivars tested in non-infected samples through quantitative analysis of free and bound phenolic compounds. The resistant cultivars showed higher amounts of major bound phenolic compounds compared to the susceptible check CDC Bold. Additionally, the FHB-infected cultivars produced significantly higher amounts of sinapic acid (SIN) () and catechin (CAT) in the soluble free form of phenolics in barley compared to the non-infected subjects. This study suggests that phenolic compounds in barley could allow barley breeders to precisely identify and develop FHB-resistant barley germplasm and cultivars. Full article

Cereals are a valuable source of biologically active compounds. Phenolic compounds, of which the phenolic acids (PA) found in cereal grains constitute a significant proportion, are characterized by health-promoting properties largely due to their antioxidant capacity. PA, located mainly in the outer parts of the grain, play an important role in preventing environmental stresses. Triticale is a cereal species of increasing economic value, and also value for human consumption. The aim of this study was to demonstrate the effect of conventional (CONV) and integrated (INTEG) cropping systems on antioxidant activity and content of selected PA in triticale cultivars (Meloman, Panteon, Belcanto) grain. The experiment was conducted in seasons from 2019/2020 to 2021/2022. Among the PA tested, ferulic acid (FER) had the highest contribution to total PA content (TPAs), with 519, 99, and 1115 μg g⁻¹ in whole grain, flour, and bran, respectively. The unfavorable hydrothermal conditions occurring in the seasons (rainfall deficit) increased TPA, mainly in whole grain. Grain cv. Meloman had the highest PA content in whole grain, flour, and bran and cv. Belcanto had the lowest, with differences of 22.7, 18.2, and 15.7% respectively. Cultivation of triticale under the CONV vs. INTEG cropping system resulted in reduced amounts of TPAs in flour and bran and PA: p-hydroxybenzoic acid (p-HB) in flour, syringic acid (SYR) in whole grain and bran, and ferulic acid (FER) and sinapic acid (SIN) in bran. The CONV cropping system also caused a decrease in antioxidant activity (AOA) in flour and bran. In most of the cases analyzed, the highest antioxidant activity and content of PA were found in bran, and the lowest were found in flour. The high presence of PA in triticale grain indicates that this cereal, especially when grown under the INTEG cropping system, can be destined for consumption and provide a source of valuable antioxidants for various food and nutraceutical purposes. Full article

The effects of supplemental UV-A (385 nm) period and UV-A intensity for 5 days before harvest (DBH) on growth, antioxidants, antioxidant capacity, and glucosinolates contents in Chinese kale (Brassica oleracea var. alboglabra Bailey) were studied in plant factory. In the experiment of the UV-A period, three treatments were designed with 10 W·m⁻² UV-A supplement, T1(5 DBH), T2 (10 DBH), and no supplemental UV-A as control. In the experiment of UV-A intensity, four treatments were designed with 5 DBH, control (0 W·m⁻²), 5 w (5 W·m⁻²), 10 w (10 W·m⁻²), and 15 w (15 W·m⁻²). The growth light is as follows: 250 μmol·m⁻²·s⁻¹; red light: white light = 2:3; photoperiod: 12/12. The growth and quality of Chinese kale were improved by supplemental UV-A LED. The plant height, stem diameter, and biomass of Chinese kale were the highest in the 5 W·m⁻² treatment for 5 DBH. The contents of chlorophyll a, chlorophyll b, and total chlorophyll were only highly increased by 5 W·m⁻² UV-A for 5 DBH, while there was no significant difference in the content of carotenoid among all treatments. The contents of soluble sugar and free amino acid were higher only under 10 DBH treatments than in control. The contents of total phenolic and total antioxidant capacity were the highest in 5 W·m⁻² treatment for 5 DBH. There was a significant positive correlation between total phenolic content and DPPH and FRAP value. After 5 DBH treatments, the percentages and contents of total aliphatic glucosinolates, sinigrin (SIN), gluconapin (GNA), and glucobrassicanapin (GBN) were highly increased, while the percentages and contents of glucobrassicin (GBS), 4-methoxyglucobrassicin (4-MGBS), and Progoitrin (PRO) were significantly decreased, especially under 10 W·m⁻² treatment. Our results show that UV-A LED supplements could improve the growth and quality of Chinese kale, and 5 W·m⁻² UV-A LED with 5 DBH might be feasible for Chinese kale growth, and 10 W·m⁻² UV-A LED with 5 DBH was better for aliphatic glucosinolates accumulation in Chinese kale. Full article

The effect of salt treatment on Brassica carinata (BC) microgreens grown under different light wavelengths on glucosinolates (GLs) and phenolic compounds were evaluated. Quantifiable GLs were identified using ultra-high performance-quadrupole time of flight mass spectrometry. Extracts’ ability to activate antioxidant enzymes (superoxide dismutase (SOD) and catalase (CAT)) was evaluated on human colorectal carcinoma cells (HCT116). Furthermore, BC compounds’ ability to activate expression of nuclear transcription factor-erythroid 2 related factor (Nrf2) and heme-oxygenase-1 (HO-1) proteins was examined using specific antibodies on HCT116 cells. Sinigrin (SIN) was the abundant GLs of the six compounds identified and its content together with total aliphatic GLs increased in saline conditions. Fluorescent (FL) and blue plus red (B1R1) lights were identified as stable cultivation conditions for microgreens, promoting biomass and glucobrassicin contents, whereas other identified individual and total indole GLs behaved differently in saline and non-saline environments. Blue light-emitting diodes and FL light in saline treatments mostly enhanced SIN, phenolics and antioxidant activities. The increased SOD and CAT activities render the BC microgreens suitable for lowering oxidative stress. Additionally, activation of Nrf2, and HO-1 protein expression by the GLs rich extracts, demonstrate their potential to treat and prevent oxidative stress and inflammatory disorders. Therefore, effective salt treatments and light exposure to BC microgreens present an opportunity for targeted regulation of growth and accumulation of bioactive metabolites. Full article

A comparative study for evaluating Italian and Spanish accessions of Brassica rapa var. rapa L., including turnip greens and turnip tops, was carried out at different locations with a view to determine the effect of earliness on crop production, antioxidant activity, glucosinolates amount, and profile (GLSs) and total phenolics content. The accessions evaluated were represented by two turnip top local varieties (one Italian variety and a Galician one), four new synthetic varieties established by Misión Biológica de Galicia (MBG-CSIC), and three commercial varieties widely used by growers in Galicia and in Italy. The results showed a great variability regarding flowering time, fresh and dry weight of the leaves and flower buds, and the branch number per plant. The highest turnip greens production was found in two synthetic varieties (“SIN07” and “SIN01”) for both countries. Local varieties “BRS550” and “CM39” were also suitable for turnip greens production in Spain and Italy, respectively. For turnip tops, the highest production was found for “SIN07” in Spain, for “CM39” in Italy and for “BRS550” in both countries. We found a high diversity in the total and individual glucosinolate, phenolic content, and antioxidant activity among genotypes, geographical origins, and the different parts of the plant (leaf and flower). Varieties “SIN01” and “SIN07” showed the highest values in total GLSs, total aliphatic and gluconapin contents in turnip greens followed by the two commercial varieties. For turnip tops, the highest values in gluconapin, aliphatic, and total GLSs contents were found in “SIN01” and “BRS550”. Even though different varieties stand out over the rest depending on the location, “SIN01”, “SIN07”, “CM39”, and “BRS550” could be recommended for turnip greens production because of its high antioxidant activity. The study showed that the latest varieties are more productive and show higher bioactive compounds than the earlier ones and that it is possible to improve genotypes for different growing cycles. Therefore, these varieties could be proposed for further breeding programs for B. rapa production. Full article

The reaction product of nitric oxide and superoxide, peroxynitrite, is a potent biological oxidant. The most important oxidative protein modifications described for peroxynitrite are cysteine-thiol oxidation and tyrosine nitration. We have previously demonstrated that intrinsic heme-thiolate (P450)-dependent enzymatic catalysis increases the nitration of tyrosine 430 in prostacyclin synthase and results in loss of activity which contributes to endothelial dysfunction. We here report the sensitive peroxynitrite-dependent nitration of an over-expressed and partially purified human prostacyclin synthase (3.3 μM) with an EC₅₀ value of 5 μM. Microsomal thiols in these preparations effectively compete for peroxynitrite and block the nitration of other proteins up to 50 μM peroxynitrite. Purified, recombinant PGIS showed a half-maximal nitration by 10 μM 3-morpholino sydnonimine (Sin-1) which increased in the presence of bicarbonate, and was only marginally induced by freely diffusing NO₂-radicals generated by a peroxidase/nitrite/hydrogen peroxide system. Based on these observations, we would like to emphasize that prostacyclin synthase is among the most efficiently and sensitively nitrated proteins investigated by us so far. In the second part of the study, we identified two classes of peroxynitrite scavengers, blocking either peroxynitrite anion-mediated thiol oxidations or phenol/tyrosine nitrations by free radical mechanisms. Dithiopurines and dithiopyrimidines were highly effective in inhibiting both reaction types which could make this class of compounds interesting therapeutic tools. In the present work, we highlighted the impact of experimental conditions on the outcome of peroxynitrite-mediated nitrations. The limitations identified in this work need to be considered in the assessment of experimental data involving peroxynitrite. Full article