Enhanced Antioxidant Enzyme Activities Research Articles

Cold shock treatment with oxalic acid could alleviate chilling injury in green bell pepper by enhancing antioxidant enzyme activity and regulating proline metabolism

The effects of cold shock, oxalic acid, and combined cold shock + oxalic acid treatments on chilling injury, antioxidant enzyme activity, and proline metabolism of cold-stored green bell pepper fruit were investigated. The results showed that cold shock, oxalic acid treatment, and their combination significantly reduced chilling injury, inhibited the increase of superoxide radical production, hydrogen peroxide content, malondialdehyde levels, and relative membrane permeability, and increased antioxidant enzyme activity. Furthermore, the treatments promoted the accumulation of proline associated with increase in ∆1-pyrroline-5-carboxylate synthetase and ornithine δ-aminotransferase activities, and decrease in proline dehydrogenase activity. The results indicate that cold shock, oxalic acid, and their combination alleviated chilling injury in green bell pepper fruit by increasing antioxidant enzyme activity and proline accumulation. The combined cold shock + oxalic acid treatment was the most effective method for reducing chilling injury, and therefore has broad future application prospects.

Impact of Biochar Application on Germination Behavior and Early Growth of Maize Seedlings: Insights from a Growth Room Experiment

Reduced germination and early crop maturity due to soil compaction, nutrients stress, and low moisture are major constraints to achieve optimum crop yield, ultimately resulting in significant economic damages and food shortages. Biochar, having the potential to improve physical and chemical properties of soil, can also improve nutrients and moisture access to plants. In the present study, a growth room experiment was conducted to assess biochar influence on maize seed germination, early growth of seedlings, and its physiological attributes. Corn cob biochar (CCB) was mixed with soil at different rates (0.5%, 1%, 1.5%, 2%, 2.5%, and 3% w/w) before seed sowing. Results obtained showed that increasing CCB application rate have neutral to positive effects on seed germination and seedling growth of maize. Biochar addition at the rate of 1.5% (w/w) significantly increased shoot dry biomass (40%), root dry biomass (32%), total chlorophyll content (a and b) (55%), germination percentage (13%), seedling vigor (85%), and relative water content (RWC) (68%), in comparison to un-amended control treatment. In addition to this, it also improved germination rate (GR) by 3% as compared to control treatment, while causing a reduction in mean emergence time (MET). Moreover, application of biochar (3%) also resulted in enhancement of antioxidant enzyme activity, particularly superoxide dismutase (SOD) and catalase (CAT) by 13% and 17%, respectively. Conclusively, biochar application is an attractive approach to improve the initial phase of plant growth and provide better crop stand and essential sustainable high yields.

Melatonin improves the photosynthesis in Dracocephalum kotschyi under salinity stress in a Ca2+/CaM-dependent manner.

This study investigated: (1) the effects of various concentrations of melatonin (MT) and Ca2+; and (2) the impact of crosstalk between these signal molecules on photosynthesis and salt tolerance of Dracocephalum kotschyi Boiss. Results indicated that 5mM CaCl2, as well as 100μM MT were the best concentrations for increasing shoot dry weight, leaf area, SPAD index, maximum quantum efficiency of photosystem II (Fv/Fm), and decreasing malondialdehyde content under salinity stress. The impact of MT on growth and photosynthesis was closely linked to its effect on enhancing antioxidant enzyme activities in leaves. Application of p-chlorophenylalanine, as an inhibitor of MT biosynthesis, negated the impacts of MT on the aforementioned attributes. Salinity and MT boosted cytosolic Ca2+ concentration. Exogenous MT, as well as Ca2+, enhanced tolerance index, membrane stability, leaf area, the content of chlorophyll (Chl) a, Chl b, and carotenoids (Car), Fv/Fm, and stomatal conductance under salinity stress. These impacts of MT were eliminated by applying a calmodulin antagonist, a Ca2+ chelator and a Ca2+ channel blocker. These novel findings indicate that the MT-induced effects on photosynthetic parameters and salt-evoked oxidative stress were mediated through calcium/calmodulin (Ca2+/CaM) signalling.

Salvia miltiorrhiza Derived Carbon Dots and Their Heat Stress Tolerance of Italian Lettuce by Promoting Growth and Enhancing Antioxidant Enzyme Activity.

With global warming, plants often suffer damage from high temperatures during the growth process, which inhibits their growth. In this work, carbon dots (CDs), synthesized by Salvia miltiorrhiza (S. miltiorrhiza) with a one-step hydrothermal method, were selected as heat-resistant enhancement agents for plants. Inspired by this background, this work studied Italian lettuce grown at 25, 35, and 45 °C and treated with CD and deionized water control (sprayed on leaves). The results showed that the biomass, chlorophyll content, net photosynthetic rate, activities of SOD (superoxide dismutase), POD (peroxidase), CAT (catalase), soluble sugar, and soluble protein contents of lettuce treated by CDs were increased while the contents of malondialdehyde (MDA) and proline (Pro) were decreased at 35 and 45 °C. The application of CDs at 35 and 45 °C could maintain the growth of plants by reducing oxidative damage and lipid peroxidation especially at the temperature of 35 °C, the growth status of lettuce treated by CDs was no different from that of lettuce grown naturally at the optimal temperature of 25 °C, or even better than the latter. This finding verified that the CDs could significantly improve the high-temperature tolerance of lettuce, thus alleviating the heat stress of plants.

Quercetin exhibits potent antioxidant activity, restores motor and non-motor deficits induced by rotenone toxicity.

The rotenone-induced animal model of Parkinson’s disease (PD) has been used to investigate the pathogenesis of PD. Oxidative stress is one of the main contributors of neurodegeneration in PD. Flavonoids have the potential to modulate neuronal function and combat various neurodegenerative diseases. The pre- and post-supplementation of quercetin (50 mg/kg, p.o) was done in rats injected with rotenone (1.5 mg/kg, s.c). After the treatment, behavioral activities were monitored for motor activity, depression-like behavior, and cognitive changes. Rats were decapitated after behavioral analysis and the brain samples were dissected out for neurochemical and biochemical estimation. Results showed that supplementation of quercetin significantly (p<0.01) restored rotenone-induced motor and non-motor deficits (depression and cognitive impairments), enhanced antioxidant enzyme activities (p<0.01), and attenuated neurotransmitter alterations (p<0.01). It is suggested that quercetin supplementation improves neurotransmitter levels by mitigating oxidative stress via increasing antioxidant enzyme activity and hence improves motor activity, cognitive functions, and reduces depressive behavior. The results of the present study showed that quercetin pre-supplementation produced more significant results as compared to post-supplementation. These findings show that quercetin can be a potential therapeutic agent to reduce the risk and progression of PD.

Effects of prebiotic oligofructose-enriched inulin on gut-derived uremic toxins and disease progression in rats with adenine-induced chronic kidney disease.

Recent studies suggest that dysbiosis in chronic kidney disease (CKD) increases gut-derived uremic toxins (GDUT) generation, leads to systemic inflammation, reactive oxygen species generation, and poor prognosis. This study aimed to investigate the effect of oligofructose-enriched inulin supplementation on GDUT levels, inflammatory and antioxidant parameters, renal damage, and intestinal barrier function in adenine-induced CKD rats. Male Sprague-Dawley rats were divided into control group (CTL, n = 12) fed with standard diet; and CKD group (n = 16) given adenine (200 mg/kg/day) by oral gavage for 3-weeks to induce CKD. At the 4th week, CKD rats were subdivided into prebiotic supplementation (5g/kg/day) for four consecutive weeks (CKD-Pre, n = 8). Also, the control group was subdivided into two subgroups; prebiotic supplemented (CTL-Pre, n = 6) and non-supplemented group (CTL, n = 6). Results showed that prebiotic oligofructose-enriched inulin supplementation did not significantly reduce serum indoxyl sulfate (IS) but did significantly reduce serum p-Cresyl sulfate (PCS) (p = 0.002) in CKD rats. Prebiotic supplementation also reduced serum urea (p = 0.008) and interleukin (IL)-6 levels (p = 0.001), ameliorated renal injury, and enhanced antioxidant enzyme activity of glutathione peroxidase (GPx) (p = 0.002) and superoxide dismutase (SOD) (p = 0.001) in renal tissues of CKD rats. No significant changes were observed in colonic epithelial tight junction proteins claudin-1 and occludin in the CKD-Pre group. In adenine-induced CKD rats, oligofructose-enriched inulin supplementation resulted in a reduction in serum urea and PCS levels, enhancement of the antioxidant activity in the renal tissues, and retardation of the disease progression.

Coating with polysaccharides influences the surface charge of cerium oxide nanoparticles and their effects to Mytilus galloprovincialis

This study focused on the effects of surface coating, acquired through the interaction with natural biomolecules, on the behavior and ecotoxicity of nanoparticles (NPs). To this aim, the effects of Cerium Oxide Nanoparticles (CeO2NPs) naked and coated with chitosan and alginate on the marine mussel Mytilus galloprovincialis were compared. Mussels were exposed for 7 days to 100 μg L−1 of CeO2NPs and for 28 days to 1 μg L−1 of CeO2NPs. In both experiments CeO2NPs were used naked and coated with the two polysaccharides. The lowest tested concentration allowed to understand the environmental relevance of this biological process. A set of biomarkers related to oxidative stress/damage and energy metabolism was applied to assess the ecotoxicity of CeO2NPs. The aggregation and stability in water of CeO2NPs were measured through dynamic light scattering analysis and the levels of Ce in the exposure media and in mussels soft tissues were determined by inductively coupled plasma-mass spectrometry. Results showed a different hydrodynamic behavior and stability of CeO2NPs in saltwater related to the different coatings. Despite this, no differences in the bioaccumulation of CeO2NPs were observed among the experimental groups. Different coatings affected also CeO2NPs toxicological outcomes in both 7- and 28-days exposures. Coating with chitosan enhanced antioxidant enzyme activities while coating with alginate triggered oxidative damage. Although the oxidant pathways did not differ that much among the exposures, biomarkers of energetic supplies suggested a different strategy of defense in response to CeO2NP exposure at a lower concentration and for a longer period of time. The obtained results are in line with findings of a previous study on freshwater mussels, suggesting that the coating with biomolecules, which impart negative charge to the NPs, might enhance their biological effects. This study highlighted that interactions of NPs with natural biomolecules largely present in the aquatic environment could affect NPs toxicity altering the interaction towards organisms.

Dietary Nucleotides Retard Oxidative Stress-Induced Senescence of Human Umbilical Vein Endothelial Cells.

Several lines of evidence suggest an inhibitory role of dietary nucleotides (NTs) against oxidative stress and inflammation, which promote senescence in age-associated cardiovascular diseases. We sought to test whether the dietary NTs could retard the hydrogen peroxide (H2O2)-induced senescence of human umbilical vein endothelial cells (HUVECs) and to elucidate the efficiency of different NTs as well as the potential mechanism. Senescence was induced in HUVECs by 4 h exposure to 200 µM H2O2 and was confirmed using senescence-associated-β-galactosidase staining (SA-β-gal), cell viability, and Western blot analyses of p16INK4A and p21Waf1/Cip1 after 24 h administration of growth medium. We find that NTs retards oxidative stress-induced HUVECs senescence, as shown by a lower percentage of SA-β-gal-positive cells, lower expression of p16INK4A, and p21Waf1/Cip1 as well as higher cell viability. GMP100 was the most excellent in delaying HUVECs senescence, which was followed by the NTs mixture, NMN, CMP50, and UMP50/100, while AMP retards HUVECs senescence by specifically reducing p15INK4b expression. NTs all have significant anti-inflammatory effects; AMP and CMP were more prominent in restoring mitochondrial function, GMP and CMP were more competent at eliminating ROS and MDA, while AMP and UMP were more efficient at enhancing antioxidant enzyme activity. The role of the NTs mixture in retarding HUVECs senescence is full-scaled. These results stated that the mechanisms of NTs retarding HUVECs senescence could be related to its antioxidant and anti-inflammation properties promoting cell proliferation and protecting mitochondrial function activities.

English

Plant growth promoting rhizobacteria (PGPRs), being the chief components of rhizosphere microbiota, are highly beneficial for plant growth and production. PGPR mediated salt stress tolerance is an intricate process which is governed by plant- bacterial interactions at molecular level. In an earlier study, positive impact of Staphylococcus scuiri SAT-17 inoculation on maize growth and physiology, under saline conditions, has been reported. To further elucidate this interaction at molecular level, salt tolerant and sensitive (FH-988 and FH-1137) maize genotypes were raised with or without inoculation of SAT-17 in the absence or presence of 120 mM NaCl. Expression analysis of various salt responsive genes (NHX1, H+-PPase, SOS1, HKT1, Cat1 and APX1) was carried out. Nutrient acquisition and translocation patterns along with few biochemical parameters were also studied. The results indicated that Na+ vacuolar sequestration and enhanced antioxidant enzyme activities might have accounted for the better salt tolerance potential of genotype FH-988 under salt stress. In contrast, genotype FH-1137 exhibited reduced Na+ vacuolar sequestration and antioxidant enzyme activities, thereby resulting in severe Na+ toxicity and oxidative damage under salt stress. Inoculation of SAT-17 ameliorated the salinity damage by maintaining optimum nutrient root-shoot translocation which in turn resulted in better Na+ homeostasis and reactive oxygen species scavenging. The results highlighted the contribution of several ion transporters, SOS pathway and antioxidant machinery in imparting salt stress tolerance in maize. The findings can be useful for devising strategies for cultivation of salt sensitive maize genotypes in saline areas thereby contributing in sustainable agricultural development.

Dietary Lactobacillus casei K17 Improves Lipid Metabolism, Antioxidant Response, and Fillet Quality of Micropterus salmoides.

Simple SummaryIn order to find effective antioxidants to improve the fleshy degeneration and liver tissue lesions of Micropterus salmoides that were fed artificial mixed feed, Lactobacillus casei K17, which displayed a high level of antioxidant activity in vitro and in vivo was selected in this study. The results indicated that after a trial for 69 days, live bacteria (LB), live bacteria protected by skim milk powder (MB), and dead bacteria were able to improve hemal and hepatic lipid metabolism and antioxidant response, reduce reactive oxygen species production, and protect Micropterus salmoides hepatic cells from injury, while LB and MB were also able to improve fillet quality. Therefore, Lactobacillus casei K17 might be a good alternative source of improving fillet quality and liver health in Micropterus salmoides.We previously demonstrated that Lactobacillus casei K17, isolated from Korean kimchi, has high antioxidant levels in vitro and in vivo. However, its effect on Micropterus salmoides is unknown. In this study, we investigated the impact of L. casei K17 supplementation on the lipid metabolism, antioxidant response, liver histology, and fillet quality of M. salmoides. We randomly assigned 450 M. salmoides (33.0 ± 0.5 g) to six diet groups for 69 days. The diets were as follows: 0.85% normal saline; 10% skim milk powder; 1 × 108 CFU/g live L. casei K17 (LB); 1 × 108 live L. casei K17 protected by skim milk powder (MB); 1 × 108 dead L. casei K17 (DB); and L. casei K17 fermentation supernatant. MB significantly improved the crude protein, total collagen, alkaline-insoluble collagen, fiber numbers, hardness, chewiness, and gumminess of M. salmoides fillets (p < 0.05). LB significantly improved crude protein and fiber numbers (p < 0.05). Furthermore, dietary supplementation with LB, MB, and DB maintained normal liver histology, preserved liver function, and increased hepatic and hemal antioxidant status by enhancing antioxidant enzyme activities. Meanwhile, the three diets also promoted lipid metabolism by increasing HDL-C effectiveness and reducing total cholesterol, triglyceride, and low-density lipoprotein cholesterol levels in serum and liver tissues, indicating that dietary supplementation with DB, LB, and MB had hypolipidemic effects on M. salmoides. MB and LB significantly improved fillet quality and LB, MB, and DB improved hemal and hepatic lipid metabolism and antioxidant response and reduced reactive oxygen species production, protecting M. salmoides hepatic cells from injury.

Influence of Local Isolates of Arbuscular Mycorrhizal Fungi on Growth and Some Physiological Performance of Zea mays Grown in Calcareous Soil as Affected by Phosphorus Levels

Arbuscular mycorrhizal fungi (AMF) are among plant-symbiotic fungi with higher plant roots. The applicability of AMF poses a strategy to minimize the deleterious effect of abiotic stress to enhance plant tolerance. Phosphorus is an essential macronutrient for plants, can cause toxic effects at low levels. Our target was to determine the mitigation effect of local inoculum of AMF on growth and metabolic activity of Zea mays under phosphorus levels. Phosphorus deficiency disturbed physiological performance however, AMF mitigated negative effects by enhancing the dry weight significantly (P < 0.05), P content and alkaline phosphatase in calcareous soil amended with P concentrations (from 15 to 120 mg P kg-1 soil), compared with non-inoculated plant. The maximum H+-ATPase activity was 28.13 µmol Pi-1ngP-1min in leaves of Zea mays in AM- inoculated soil and amended with 60 mg P kg-1soil. AMF enhanced antioxidant enzyme activities, superoxide dismutase (SOD), catalase (CAT), ascorbate peroxidase (APX) and glutathione reductase (GR) together with their substrates glutathione (GSH) and ascorbic acid (AA), with concurrent reduction of lipid peroxidation and hydrogen peroxide content. Highest mycorrhizal colonization (88%) recorded in maize grown in 60 mg P kg-1 soil. Established data on morphological characters revealed AMF local isolates belong to four native spores related to genus Glomus, Acaulospora, Scutellospora and Entrophospora. Analysis of the genetic material confirmed that spores were related to Glomus mosseae and Acaulospora spinose. These findings demonstrate that root colonization by local AMP inoculum could ameliorate the phosphorus deficiency in calcareous soils collected from Southwestern coast of Egypt

Acclimation to NaCl and H2O2 develops cross tolerance to saline-alkaline stress in Rice (Oryza sativa L.) by enhancing fe acquisition and ROS homeostasis

ABSTRACT Plants are known to develop cross-tolerance in which plants tolerate to one stress following prior exposure to another stress. In this study, we investigated this phenomenon in rice (Oryza sativa L.) to elucidate the underlying physiological mechanisms. Twenty-one (21) day-old seedlings were pre-exposed to various concentrations of NaCl, NaHCO3, and H2O2 for 7 days and then subjected to saline-alkaline stress (SAS) for 14 days. The present findings report that pre-exposure to 10 mM NaCl and 10 µM H2O2 develops cross-tolerance to SAS by triggering systemic physiological processes involved in Fe uptake and ROS homeostasis. While the mechanisms of this tolerance vary among pre-treatments, a consensus suggests the relevance of the following processes: (1) the ability to maintain a lower growth medium pH, (2) ability to suppress root K+ losses, (3) maintenance of a stable acquisition of Fe and P and (4) regulated generation of reactive oxygen species (ROS) via enhanced antioxidant enzyme activities. Taken together, these results are consistent with the hypothesis that a crosstalk exists between salinity stress, oxidative stress, and SAS, triggering adaptive physiological responses that develop tolerance to SAS in rice, a phenomenon that offers a prospect for developing plants tolerant to multiple stressors.

Effects of dietary supplementation of glucose oxidase, catalase, or both on reproductive performance, oxidative stress, fecal microflora and apoptosis in multiparous sows.

ObjectiveThe objective of this experiment was to investigate the effect of dietary glucose oxidase (GOD), catalase (CAT), or both supplementation on reproductive performance, oxidative stress, and apoptosis in sows.MethodsA total of 104 multiparous sows were randomly assigned to four groups (n = 26) with each group given a basal diet, basal diet plus GOD at 60 U/kg, basal diet plus CAT at 75 U/kg, and basal diet plus GOD at 60 U/kg and CAT at 75 U/kg. Sows were fed the experimental diets throughout gestation and lactation.ResultsDietary GOD supplementation increased average daily feed intake of sows and litter weight at weaning (p<0.05). Dietary CAT supplementation reduced the duration of parturition, stillbirth, and piglet mortality and increased growth performance of weaned piglets (p<0.05). Dietary GOD and CAT supplementation enhanced antioxidant enzyme activities and lessened oxidative stress product levels in plasma of sows and elevated antioxidant capacity of 14-day milk and plasma in weaned piglets (p<0.05). Dietary GOD supplementation increased fecal Lactobacillus counts and reduced Escherichia coli counts of sows (p<0.05). Compared with the basal diet, the GOD diet reduced fecal Escherichia coli counts of sows, but the addition of CAT did not reduce Escherichia coli counts in the GOD diet. Dietary GOD and CAT supplementation reduced the apoptosis rate of the liver, endometrium, and ovarian granulosa cells in sows (p<0.05). In the liver, uterus, and ovary of sows, the mRNA expression of caspase-3 and caspase-9 was downregulated by dietary GOD and CAT supplementation (p<0.05).ConclusionDietary GOD and CAT supplementation could improve the antioxidant capacity of sows and weaned piglets, and alleviate hepatic, ovarian and uterine apoptosis by weakening apoptosis-related gene expression. Glucose oxidase regulated fecal microflora of sows, but supplementation of CAT to GOD could weaken the inhibitory effect of GOD on fecal Escherichia coli.

Physiological response of Arizona cypress to Cd-contaminated soil inoculated with arbuscular mycorrhizal fungi and plant growth promoting rhizobacteria

Increasing some industrial activities has been constantly contaminated the soil with different toxic metals leading to serious environmental concerns. However, some beneficial soil microorganisms would be useful tools for reducing toxic effects of heavy metals without producing toxic residuals. Therefore, present study was conducted to evaluate potential role of Pseudomonas fluorescens and arbuscular mycorrhizal fungi (AMF) in reducing cadmium toxicity in the Arizona cypress seedlings both individually and in combination. Factorial experiment was conducted based on a completely randomized design with three factors comprising AMF inoculation (Rhizophagus irregularis or Funneliformis mosseae or a mixture of both species, and non-inoculated controls), bacterial inoculation (P. fluorescens or Non-inoculated), and five levels of Cd (0, 5, 10, 15, and 20 mg kg−1) using three replications. Results of this study showed that, Arizona cypress growth decreased when exposed to high levels of Cd contamination. However, co-inoculation plants with all mycorrhizae and P. fluorescens grown under the highest levels of Cd contamination, showed increased photosynthetic pigments. Furthermore, AMF and P. fluorescens increased ascorbate peroxidase activity, which is responsible for the elimination of H2O2 when plants exposed to Cd stress. Moreover, high levels of Cd contamination negatively influenced phosphorus uptake by the plants, especially in control plants. Moreover, in seedlings inoculated with mycorrhizal fungi, accumulation of Cd was found to be less, apparently as a result of AMF modification of the influx of Cd into the host plants, as confirmed by reduced hydrogen peroxide and enhanced antioxidant enzyme activities compared to the control plants. AMF treatments increased glomalin related soil proteins concentration compared to the control plants. Also, the highest amount of glomalin production was observed in two species of Mix and FM. In conclusion, either co-inoculation with AMF and P. fluorescens or individual inoculation with AMF could potentially ameliorate harmful effects of Cd on Arizona cypress growth. .

Alleviating damage of photosystem and oxidative stress from chilling stress with exogenous zeaxanthin in pepper (Capsicum annuum L.) seedlings

As a typical thermophilous vegetable, the growth and yield of peppers are easily limited by chilling conditions. Zeaxanthin, a crucial carotenoid, positively regulates plant abiotic stress responses. Therefore, this study investigated the regulatory mechanisms of zeaxanthin-induced chilling tolerance in peppers. The results indicated that the pretreatment with zeaxanthin effectively alleviated chilling damage in pepper leaves and increased the plant fresh weight and photosynthetic pigment content under chilling stress. Additionally, alterations in photosynthetic chlorophyll fluorescence parameters and chlorophyll fluorescence induction curves after zeaxanthin treatment highlighted the participation of zeaxanthin in improving the photosystem response to chilling stress by heightening the quenching of excess excitation energy and protection of the photosynthetic electron transport system. In chill-stressed plants, zeaxanthin treatment also enhanced antioxidant enzyme activity and transcript expression, and reduced hydrogen peroxide (H2O2) and superoxide anion (O2•-) content, resulting in a decrease in biological membrane damage. Additionally, exogenous zeaxanthin upregulated the expression levels of key genes encoding β-carotene hydroxylase (CaCA1, CaCA2), zeaxanthin epoxidase (CaZEP) and violaxanthin de-epoxidase (CaVDE), and promoted the synthesis of endogenous zeaxanthin during chilling stress. Collectively, exogenous zeaxanthin pretreatment enhances plant tolerance to chilling by improving the photosystem process, increasing oxidation resistance, and inducing alterations in endogenous zeaxanthin metabolism.

Protective Effects of Antioxidant Chlorophyllin in Chemically Induced Breast Cancer Model In vivo.

Glutathione-related enzymes belong to the protection mechanism of the cells against harmful oxidative damage and chemicals. Glutathione S-transferase (GST) is frequently over-expressed in various cancer cells and is involved in drug resistance. Chlorophyllin is an antioxidant molecule interfering with the GST P1-1 activity. The purpose of this study is to evaluate the short- and long-term protective effects of chlorophyllin as an antioxidant molecule on DNA damage, antioxidant enzyme activities, trace elements, and minerals in chemically induced breast cancer model in vivo. In our study, N-methyl-N-nitrosourea (MNU) was used for inducing breast carcinogenesis in female Sprague-Dawley rats. A total of 36 rats were divided into groups as short term and long term. Each group was divided into four sub-groups as control group received physiological saline solution (n= 3), Chl group (n= 5) received chlorophyllin, MNU group (n= 5) was administered MNU, and Chl + MNU group (n= 5) was treated with both chlorophyllin and MNU. Results illustrated that chlorophyllin had a significant anti-genotoxic effect in the short term, and glutathione-related enzyme activities were protected by chlorophyllin treatment in MNU-induced breast cancer model. Additionally, MNU administration impaired mineral and trace element levels including Na, Mg, K, Fe, Zn, and Co in the liver, kidney, spleen, heart, and tumor tissues; however, adverse effects of MNU were recovered upon chlorophyllin treatment in the indicated tissues of the rats. In conclusion, chlorophyllin can be used as an antioxidant molecule to ameliorate adverse effects of MNU by enhancing antioxidant enzyme activities and regulating trace element and mineral balance in several organs and tumor tissue in the breast cancer model.

Dietary bisdemethoxycurcumin supplementation attenuates lipopolysaccharide-induced damages on intestinal redox potential and redox status of broilers

This study was conducted to investigate the beneficial effects of bisdemethoxycurcumin (BDC) on growth performance, glutathione (GSH) redox potential, antioxidant enzyme defense, and gene expression in lipopolysaccharide (LPS)-challenged broilers. A total of 320, male, 1-day-old broilers were randomly assigned to 4 treatment groups including 8 replicates with 10 birds per cage in a 2 × 2 factorial arrangement: BDC supplementation (a basal diet with 0 or 150 mg/kg BDC) and LPS challenge (intraperitoneal injection of 1 mg/kg body weight saline or LPS at 16, 18, and 20 d of age). Results showed that dietary BDC supplementation prevented the LPS-induced decrease in ADG of broilers (P < 0.05). Compared to the saline-challenged group, LPS-challenged broilers showed higher jejunal and ileal malondialdehyde (MDA), protein carbonyl (PC), and 8-hydroxy-2′-deoxyguanosine (8-OHdG) contents (P < 0.05). Dietary BDC supplementation alleviated LPS-induced increases in jejunal 8-OHdG, ileal MDA, and PC contents (P < 0.05). LPS challenge impaired the small intestinal antioxidant system, as evident by the decreases of GSH and total thiol contents, as well as superoxide dismutase (SOD), glutathione peroxidase, glutathione reductase (GR), and glutathione S-transferase (GST) activities. On the other hand, LPS challenge also increased GSH redox potential and oxidized glutathione (GSSG) contents (P < 0.05). Dietary BDC supplementation increased jejunal and ileal GSH contents, SOD activities, jejunal GR activity, and ileal GST activity, while it decreased jejunal and ileal redox potential, and jejunal GSSG contents (P < 0.05). Dietary BDC supplementation significantly alleviated the downregulation of mRNA expression levels of jejunal and ileal copper and zinc superoxide dismutase, catalytic subunit of γ-glutamylcysteine ligase, nuclear factor erythroid-2-related factor 2, heme oxygenase 1, NAD(P)H quinone oxidoreductase 1, and jejunal catalase and GR induced by LPS challenge (P < 0.05). In conclusion, BDC demonstrated favorable protection against LPS-induced small intestinal oxidative damages, as indicated by the improved growth performance, decreased GSH redox potential, enhanced antioxidant enzyme activities, and upregulated antioxidant-related gene expression.

Phytosynthesis of poly (ethylene glycol) methacrylate-hybridized gold nanoparticles from C. tuberculata: their structural characterization and potential for in vitro growth in banana

Here, we are analyzing the comparative study of green-synthesized biogenic Caralluma tuberculata gold nanoparticles (Ca-AuNPs) and poly (ethylene glycol) methacrylate coated Ca-AuNPs nanocomposites (PEGMA-AuNPs), formed by hybridization of Ca-AuNPs with PEGMA. Both the virgin and polymer-capped materials (polymer hybrid) were physico-chemically characterized, using Fourier transform infrared spectroscopy (FTIR) that revealed physical interactions during coating without new peak, as PEGMA did not disturb the crystal structure of the AuNPs. However, a red shift of AuNPs from 450 to 520 nm was observed and the overall particle size of AuNPs was increased after PEGMA coating (50 to 100 nm). Furthermore, an efficient protocol of biomass enhancement of in vitro micropropagated Musa acuminate was achieved upon supplementation with Ca-AuNPs and PEGMA-Ca-AuNPs, in the Murashige and Skoog (MS) media in a dose-dependent manner. The maximum fresh, dry weight, and shoot length were achieved upon 80 ppm PEGMA-Ca-AuNPs supplementation. In the physiological analysis, higher chlorophyll content, abundant soluble sugar, and elevated moisture content also appeared upon 80 ppm PEGMA-AuNPs addition. Phytohormone analysis showed over-accumulation of IAA content, while on contrary, decreased MDA and H2O2 content, higher production of phenolics, flavonoids, phenylalanine ammonia lyase activity, and antioxidant activity was noticeable upon 80 ppm PEGMA-AuNPs supplementation. Moreover, enhanced antioxidant enzyme activities including CAT, SOD, POD, and APx were detected at 80 ppm PEGMA-Ca-AuNPs supplementation in MS media. It can be concluded that the PEGMA-AuNPs elicitation can be effectively used in plant tissue culture and agricultural industry, for sustainable promotion of biomass and secondary metabolic through modulating the physiological, biochemical, and bioactive antioxidants status and modifying cell wall properties.

Physiological introspection of leaf photochemical activity and antioxidant metabolism in selected indigenous finger millet genotypes in relation to drought stress

Drought stress often impairs growth and yield of finger millets worldwide. The present study investigated the drought stress responses in four indigenous finger millets (Gangabali, Dengsameli, Kada and Badu) of Koraput compared to one improved variety (Bhairabi) under simulated drought condition at the early growth stage. The physiological and biochemical responses of indigenous finger millets were assessed through chlorophyll fluorescence technique, photosynthetic pigments, antioxidants, proline, protein and lipid peroxidation. The results showed that drought treatment significantly declined the photosystem (PS) II activity by declining the maximal fluorescence, maximum photochemical efficiency of PSII, yield of PSII photochemistry, electron transport rate and photochemical quenching with concomitant increase in minimum fluorescence and non-photosynthetic quenching compared to the respective control plants. Further, the present finding indicates that finger millet leaves responded to PEG-induced drought stress by significantly enhancing antioxidant enzyme activity. The proline accumulation was increased with increasing concentration of drought, which suggests that plants’ ability to resist the effect of drought. Based on the phenotypic response under drought stress, indigenous finger millet genotypes such as Gangabali and Badu showed superior drought tolerance capacity than the improved genotype (Bhairabi) during seedling stages. Overall, the results suggest that these indigenous finger millet genotypes may be beneficial for rainfed areas affected by drought stresses and can be used for future breeding programs.

The ThSOS3 Gene Improves the Salt Tolerance of Transgenic Tamarix hispida and Arabidopsis thaliana.

The salt overly sensitive (SOS) signal transduction pathway is one of the most highly studied salt tolerance pathways in plants. However, the molecular mechanism of the salt stress response in Tamarix hispida has remained largely unclear. In this study, five SOS genes (ThSOS1–ThSOS5) from T. hispida were cloned and characterized. The expression levels of most ThSOS genes significantly changed after NaCl, PEG6000, and abscisic acid (ABA) treatment in at least one organ. Notably, the expression of ThSOS3 was significantly downregulated after 6 h under salt stress. To further analyze ThSOS3 function, ThSOS3 overexpression and RNAi-mediated silencing were performed using a transient transformation system. Compared with controls, ThSOS3-overexpressing transgenic T. hispida plants exhibited greater reactive oxygen species (ROS)-scavenging capability and antioxidant enzyme activity, lower malondialdehyde (MDA) and H2O2 levels, and lower electrolyte leakage rates under salt stress. Similar results were obtained for physiological parameters in transgenic Arabidopsis, including H2O2 and MDA accumulation, superoxide dismutase (SOD) and peroxidase (POD) activity, and electrolyte leakage. In addition, transgenic Arabidopsis plants overexpressing ThSOS3 displayed increased root growth and fresh weight gain under salt stress. Together, these data suggest that overexpression of ThSOS3 confers salt stress tolerance on plants by enhancing antioxidant enzyme activity, improving ROS-scavenging capability, and decreasing the MDA content and lipid peroxidation of cell membranes. These results suggest that ThSOS3 might play an important physiological role in salt tolerance in transgenic T. hispida plants. This study provides a foundation for further elucidation of salt tolerance mechanisms involving ThSOSs in T. hispida.