Combination of Sodium Nitroprusside and Controlled Atmosphere Maintains Postharvest Quality of Chestnuts through Enhancement of Antioxidant Capacity.

The purpose of this study was to clarify the effect of CA (controlled atmosphere, 2-3% O2 + 3% CO2) and NO (nitric oxide, generated by 0.4 nM sodium nitroprusside), alone or combined (CA + NO), on the physio-chemical properties, enzyme activities and antioxidant capacities of chestnuts during storage at 0 °C for 180 d. Compared with control (CT), CA and CA+NO both improved the storage quality of the samples, but only CA resulted in more ethanol production. Moreover, these improvements were further enhanced and ethanol synthesis was inhibited by the addition of NO. A spectrometer was used to assess the production of phenolic content (TPC) and activities of phenylalanine ammonia-lyase (PAL), superoxide dismutas (SOD), peroxidase (POD), catalase (CAT) and polyphenol oxidase (PPO) as influenced by CA or CA+NO treatments. Higher TPC, PAL, SOD, POD, CAT, and lower PPO were observed in CA alone, and more so in the combination with NO group. The increased antioxidant production and enhanced antioxidant activities contributed to scavenging reactive oxygen species (ROS) and reducing malondialdehyde (MDA). This study unveiled the correlations and differences between the effects of CA and CA+NO on storage quality, providing valuable insights into postharvest preservation and suggesting that the combination (CA+NO) was more beneficial for quality maintenance in chestnuts.

Meta-analysis of citrus-derived additives on chicken meat quality and safety: a comprehensive evaluation of acceptability, physicochemical properties, and microbial contamination.

Citrus represents a valuable repository of antioxidant substances that possess the potential for the preservation of meat quality. This meta-analysis aimed to comprehensively assess the impact of citrus additives on the quality and safety of chicken meat. Adhering to the PRISMA protocol, we initially identified 103 relevant studies, from which 20 articles meeting specific criteria were selected for database construction. Through the amalgamation of diverse individual studies, this research provides a comprehensive overview of chicken meat quality and safety, with a specific focus on the influence of citrus-derived additives. Minimal alterations were observed in the nutritional quality of chicken meat concerning storage temperature and duration. The findings demonstrated a significant reduction in aerobic bacterial levels, with Citrus aurantiifolia exhibiting the highest efficacy (P < 0.01). Both extracted and nonextracted citrus components, applied through coating, curing, and marinating, effectively mitigated bacterial contamination. Notably, thiobarbituric acid reactive substances (TBARS) concentrations were significantly reduced, particularly with Citrus hystrix (P < 0.01). Total volatile base nitrogen (TVBN), an indicator of protein degradation, exhibited a decrease, with citrus extract displaying enhanced efficacy (P < 0.01). Chemical composition changes were marginal, except for a protein increase after storage (P < 0.01). Hedonic testing revealed varied preferences, indicating improvements in flavor, juiciness, and overall acceptability after storage (P < 0.01). The study underscores the effectiveness of citrus additives in preserving chicken meat quality, highlighting their antibacterial and antioxidant properties, despite some observed alterations in texture and chemical composition. Citrus additives have been proven successful in 1) mitigating adverse effects on chicken meat during storage, especially with Citrus hystrix exhibiting potent antimicrobial properties, and 2) enhancing the hedonic quality of chicken meat. This research strongly advocates for the application of citrus additives to uphold the quality and safety of chicken meat.

Effects of Increasing Levels of Total Tannins on Intake, Digestibility, and Balance of Nitrogen, Water, and Energy in Hair Lambs.

This study aims to evaluate the effects of increasing tannin levels from Mimosa tenuiflora hay on the intake, digestibility, and balance of nitrogen (N), water, and energy in hair lambs. Thirty-two Santa Ines lambs, at an average age of 150 days and body weight of 26.75 ± 2.29 kg, were randomly assigned to four treatments in a completely randomized design. The treatments consisted of four diets: a control diet, tannin-free, and three diets with increasing levels of total tannin, 26.2, 52.4, and 78.6 g tannin/kg dry matter (DM). Including the total tannins in the lambs' diet led to a quadratic increase in the intake of nutrients, N-retention (g/day), water intake, water absorption and retention, energy intake, and energy excretion in feces and gases. However, the digestibility of crude protein, neutral and acid detergent fibers, and total carbohydrates decreased. It was observed that there is a correlation between the variable nutrient digestibility and N-ingested and the N-absorbed, N-urinary, and N-retained. However, the N-excreted in feces did not correlate with any of the variables studied. It is recommended to include 33 g/kg DM of total natural tannins from Mimosa tenuiflora hay in the diet of hair lambs, as it improves intake, energy balance, dietary N, and body water composition while reducing the excretion of N-urinary and gas emissions to the environment.

[Physiological and biochemical mechanisms of brassinosteroid in improving anti-cadmium stress ability of Panax notoginseng].

In this study, the effect of brassinosteroid(BR) on the physiological and biochemical conditions of 2-year-old Panax notoginseng under the cadmium stress was investigated by the pot experiments. The results showed that cadmium treatment at 10 mg·kg~(-1) inhibited the root viability of P. notoginseng, significantly increased the content of H_2O_2 and MDA in the leaves and roots of P. noto-ginseng, caused oxidative damage of P. notoginseng, and reduced the activities of SOD and CAT. Cadmium stress reduced the chlorophyll content of P. notoginseng, increased leaf F_o, reduced F_m, F_v/F_m, and PIABS, and damaged the photosynthesis system of P. notoginseng. Cadmium treatment increased the soluble sugar content of P. notoginseng leaves and roots, inhibited the synthesis of soluble proteins, reduced the fresh weight and dry weight, and inhibited the growth of P. notoginseng. External spray application of 0.1 mg·L~(-1) BR reduced the H_2O_2 and MDA content in P. notoginseng leaves and roots under the cadmium stress, alleviated cadmium-induced oxidative damage to P. notoginseng, improved the antioxidant enzyme activity and root activity of P. notoginseng, increased the content of chlorophyll, reduced the F_o of P. notoginseng leaves, increased F_m, F_v/F_m, and PIABS, alleviated the cadmium-induced damage to the photosynthesis system, and improved the synthesis ability of soluble proteins. In summary, BR can enhance the anti-cadmium stress ability of P. notoginseng by regulating the antioxidant enzyme system and photosynthesis system of P. notoginseng under the cadmium stress. In the context of 0.1 mg·L~(-1) BR, P. notoginseng can better absorb and utilize light energy and synthesize more nutrients, which is more suitable for the growth and development of P. notoginseng.

Effects of field soil warming on the growth and physiology of Juglans mandshurica seedlings.

Global climate change will increase surface soil temperature, with consequences on plant seedling growth and population dynamics. In this study, we carried out a field experiment to investigate the effects of 2 ℃ soil warming on the growth and physiological characteristics of 1- and 2-year-old seedlings of a dominant tree species in broadleaved Korean pine forest, Juglans mandshurica. The results showed that soil warming significantly increased basal diameter, root length, total leaf area, leaf dry weight, root dry weight, total biomass, apparent photosynthetic electron transfer rate (ETR), PSⅡ actual photochemical efficiency (ΦPSⅡ), and apparent photosynthetic electrophotochemical quenching coefficient (qP) of 1-year-old seedlings by 18.3%, 66.7%, 94.4%, 105.9%, 95.8%, 37.8%, 89.5%, 100.0%, and 71.4%, respectively. Soil warming significantly increased basal diameter, total leaf area, leaf dry weight, total biomass, leaf superoxide dismutase activity, peroxidase activity, catalase activity and free proline content, ETR, ΦPSⅡ, and qP of 2-year-old seedlings by 12.5%, 180.5%, 97.3%, 42.5%, 23.9%, 20.4%, 14.9%, 20.7%, 66.7%, 283.3% and 284.6%, respectively. There was an interaction between seedling age and soil warming on the root-shoot ratio and the ΦPSⅡ and qP in chlorophyll fluorescence parameters, in that soil warming significantly reduced the root-shoot ratio of 2-year-old seedlings and that the increase of chlorophyll fluorescence parameters of 2-year-old seedlings (4.1-4.6 times) was much higher than that of 1-year-old seedlings (1.5-1.8 times). Soil warming of 2 ℃ was beneficial to the growth of 1- and 2-year-old J. mandshurica seedlings and increased their regeneration potential. In particular, 2-year-old J. mandshurica seedlings responded to soil warming by increasing leaf area, improving leaf photochemical efficiency, and enhancing protective enzyme activity to increase resistance.

Physiological and biochemical mechanisms of brassinosteroid in improving anti-cadmium stress ability of Panax notoginseng / 中国中药杂志

In this study, the effect of brassinosteroid(BR) on the physiological and biochemical conditions of 2-year-old Panax notoginseng under the cadmium stress was investigated by the pot experiments. The results showed that cadmium treatment at 10 mg·kg~(-1) inhibited the root viability of P. notoginseng, significantly increased the content of H_2O_2 and MDA in the leaves and roots of P. noto-ginseng, caused oxidative damage of P. notoginseng, and reduced the activities of SOD and CAT. Cadmium stress reduced the chlorophyll content of P. notoginseng, increased leaf F_o, reduced F_m, F_v/F_m, and PIABS, and damaged the photosynthesis system of P. notoginseng. Cadmium treatment increased the soluble sugar content of P. notoginseng leaves and roots, inhibited the synthesis of soluble proteins, reduced the fresh weight and dry weight, and inhibited the growth of P. notoginseng. External spray application of 0.1 mg·L~(-1) BR reduced the H_2O_2 and MDA content in P. notoginseng leaves and roots under the cadmium stress, alleviated cadmium-induced oxidative damage to P. notoginseng, improved the antioxidant enzyme activity and root activity of P. notoginseng, increased the content of chlorophyll, reduced the F_o of P. notoginseng leaves, increased F_m, F_v/F_m, and PIABS, alleviated the cadmium-induced damage to the photosynthesis system, and improved the synthesis ability of soluble proteins. In summary, BR can enhance the anti-cadmium stress ability of P. notoginseng by regulating the antioxidant enzyme system and photosynthesis system of P. notoginseng under the cadmium stress. In the context of 0.1 mg·L~(-1) BR, P. notoginseng can better absorb and utilize light energy and synthesize more nutrients, which is more suitable for the growth and development of P. notoginseng.

Biochemical responses of hairgrass (Deschampsia caespitosa) to hydrological change.

Plant growth and development are closely related to water availability. Water deficit and water excess are detrimental to plants, causing a series of damage to plant morphology, physiological and biochemical processes. In the long evolutionary process, plants have evolved an array of complex mechanisms to combat against stressful conditions. In the present study, the duration-dependent changes in ascorbate (AsA) and glutathione (GSH) contents and activities of enzymes involved in the AsA-GSH cycle in hairgrass (Deschampsia caespitosa) in response to water stress was investigated in a pot trial using a complete random block design. The treatments were as follows: (1) heavily waterlogging, (2) moderate waterlogging, (3) light waterlogging, (4) light drought, (5) moderate drought, (6) heavily drought, and (7) a control (CK) with plant be maintained at optimum water availability. The hairgrass plants were subjected to waterlogging or drought for 7, 14, 21 and 28 days and data were measured following treatment. Results revealed that hairgrass subjected to water stress can stimulate enzymatic activities of ascorbate peroxidase (APX), glutathione peroxidase (GPX), glutathione reductase (GR), dehydroascorbate reductase (DHAR), monodehydroascorbate reductase (MDHAR) and L-galactono-1, 4-lactone dehydrogenase (GalLDH), switched on the ascorbate-glutathione (AsA-GSH) cycle and the L-galactose synthesis, up-regulated the contents of AsA and GSH, and maintained higher ratios of ascorbate to dehydroascorbate (AsA/DHA) and reduced glutathione to oxidized glutathione (GSH/GSSG) to alleviate potential oxidative damage. However, the light waterlogging did not induce hairgrass under stress to switch on the AsA-GSH pathway. In general, the critic substances and enzyme activities in AsA-GSH metabolic pathway increased as the increase of water stress intensity. As the increase of exposure duration, the critic antioxidant substances content and enzyme activities increased first and then maintained a relatively stable higher level. Our findings provide comprehensive information on biochemical responses of hairgrass to hydrological change, which would be a major step for accelerating ecological restoration of degradation alpine marshes in the Qinghai-Tibetan Plateau.

Antioxidant capacity of soymilk yogurt and exopolysaccharides produced by lactic acid bacteria.

Reactive oxygen species (ROS), such as hydroxyl and superoxide anion radicals, are highly reactive molecules derived from the metabolism of oxygen. ROS play positive roles in cell physiology, but they may also damage cell membranes and DNA, inducing oxidation that causes membrane lipid peroxidation and decreases membrane fluidity. Soymilk yogurt, which is soymilk fermented using lactic acid bacteria (LAB), is an excellent food item with numerous functional substances with antioxidant effects. In this study, the antioxidative activities of soymilk yogurt were investigated. Sixteen of the 26 tested LAB strains solidified soymilk. In antioxidant capacity tests for bacterial cells, Leuconostoc mesenteroides MYU 60 and Pediococcus pentosaceus MYU 759 showed the highest values in the oxygen radical antioxidant capacity (ORAC) and hydroxyl radical antioxidant capacity (HORAC) tests, respectively. The supernatant of soymilk yogurt made with Lactobacillus gasseri MYU 1 showed the highest ORAC and HORAC values. L. mesenteroides MYU 60, Lactobacillus plantarum MYU 74, Lactobacillus reuteri MYU 220, and P. pentosaceus MYU 759 showed significantly high N-acetylcysteine equivalent values compared with the control in a total ROS reducing assay (p<0.05). These strains were selected, and a comet assay was performed, which exhibited decreased values in all selected strains compared with the control, indicating DNA protection. An acidic exopolysaccharide produced by P. pentosaceus MYU 759 showed high antioxidant capacity. The antioxidant substances produced by LAB fermentation may be exopolysaccharides, antioxidant peptides, and isoflavone aglycones. Soymilk yogurt can be used as a functional food useful for various diseases related to oxidation.

STUDY ON EXTRACTION AND BIOLOGICAL ACTIVITY OF ANTIOXIDANT SUBSTANCE OF SWEET POTATOES / 营养学报

Objective: The chemical composition, extraction and biological activity of antioxidant substance of sweet potatoes were studied. Method: The antioxidant substance was extracted with alcohol and purified with AB-8 big-hole resin and its elimination rate of _?O 2 and OH and SOD activity were determined.Results: The content of antioxidant substance stockpiled respectively in the root tubers, stems and leaves of sweet potatoes and was different in varieties. The highest content in the root tuber was 0.324%, which accounted 70% of total content in sweet potatoes. Its extraction ratio was 85%. The major composition of the antioxidant substance was phenol acid, including chlorogenic acid,isochlorogenic acid,neochlorogenic acid and 4-0-caffeonyl quinic butyl ester. They had intense antioxidant function and their elimination rate to _?O 2 and?OH at concentration 90 mg/ml was 88.02% and 82.21% respectively. The antioxidantsubstance restrained oxidation of lipid and hemolysis of red cell induced by H2O2,and increased SOD activity in serum and skin of mice. Conclusion: Several kinds of phenol acid as antioxidant substance stockpiled in sweet potatoes were proved to have strong antioxidant activity.