Total Soluble Protein Levels Research Articles

Responses of Dunaliella sp. AL-1 to chromium and copper: Biochemical and physiological studies

Microalgae have gained recognition as versatile candidates for the remediation of heavy metals (HMs). This study investigated the biosorption potential of Dunaliella sp. AL1 for copper (Cu(II)) and hexavalent chromium (Cr(VI)) in aqueous solutions. The marine microalga Dunaliella sp. AL1 was exposed to half-sublethal concentrations of both metals in single and bimetallic systems, and responses in algal growth, oxidative stress, photosynthetic pigment production, and photosynthetic performance were evaluated. Cu and/or Cr exposure increased the generation of reactive oxygen species (ROS) in microalgae cells but did not impact algal growth. In terms of photosynthesis, there was a decrease in chlorophylls and carotenoids production in the microalgae culture treated with Cr, either alone or in combination with Cu. The study recorded promising metal removal efficiencies: 26.67%–20.11% for Cu and 94.99%–95.51% for Cr, in single and bimetallic systems, respectively. FTIR analysis revealed an affinity of Cu and Cr ions towards aliphatic/aldehyde C–H, N–H bending, and phosphate groups, suggesting the formation of complex bonds. Biochemical analysis of microalgae biomass collected after the removal of Cr alone or in combination with Cu showed a significant decrease in total carbohydrate content and soluble protein levels. Meanwhile, higher lipid accumulation was recorded and evidenced by BODIPY 505/515 staining. Fatty acid composition analysis by GC revealed a modulation in lipid composition, with a decrease in the ratio of unsaturated fatty acids (UFA) to saturated fatty acids (SFA), in response to Cu, Cr, and Cu–Cr exposure, indicating the suitability of the biomass for sustainable biofuel production.

Ectoine maintains the flavor and nutritional quality of broccoli during postharvest storage

The bacterial derived osmolyte ectoine has been shown to stabilize cell structure and function, a property that may help to extend the shelf life of broccoli. The impact of ectoine on broccoli stored for 4 d at 20 °C and 90% relative humidity was investigated. Results indicated that 0.20% ectoine treatment maintained the quality of broccoli, by reducing rate of respiration and ethylene generation, while increasing the levels of total phenolics, flavonoids, TSS, soluble protein, and vitamin C, relative to control. Headspace-gas chromatography–mass spectrometry, transcriptomic and metabolomic analyses revealed that ectoine stabilized aroma components in broccoli by maintaining level of volatile compounds and altered the expression of genes and metabolites associated with sulfur metabolism, as well as fatty acid and amino acid biosynthesis pathways. These findings provide a greater insight into how ectoine preserves the flavor and nutritional quality of broccoli, thus, extending its shelf life.

Total Soluble Protein Mediated Morphological Traits in Mustard Treated with Thiourea and Salicylic Acid

The total soluble protein-mediated morphological traits in mustard treated with Thiourea and Salicylic acid were investigated. In addition, it tested the hypothesis that the growth regulator salicylic acid protects the photosynthetic apparatus by up-regulating morphological traits. Under natural environmental conditions, seeds were sown in the field, and seed emergence was recorded. For three days after the 15-day stage, plants in the area were treated with thiourea and salicylic acid and allowed to grow for 90 days. Plants were harvested to assess various morphological traits. A follow-up application of SA and Thiourea plants improved plant height, leaf area, internodal length, leaf number, and accelerated plant activity. The up-regulation of morphological traits may have occurred in SA and Thiourea-mediated plants. After treatments, the level of total soluble protein was estimated in the leaves at proposed day intervals.

Composite Coating of Oleaster Gum Containing Cuminal Keeps Postharvest Quality of Cherry Tomatoes by Reducing Respiration and Potentiating Antioxidant System.

Exploring the green and affordable protection of perishable cherry tomato fruits during storage, herein, the protective efficacy, and its underpinning mechanisms, of a coating of oleaster gum, alone or incorporated with cuminal, on cherry tomatoes stored at ambient temperature was investigated. The composite coating of oleaster gum with 0.1% cuminal reduced the decay, respiration rate, weight loss, and softening of the fruits and decelerated the decreases in their total soluble solid, titratable acidity, and soluble protein levels, and therefore maintained their marketability. Furthermore, it reduced the accumulation of O2·- and H2O2 in the fruits and mitigated cell membrane lipid oxidation and permeabilization, thereby retarding their senescence. Instrumentally, it elevated the activities of superoxide dismutase, catalase, peroxidase, and ascorbate peroxidase and the levels of ascorbic acid and glutathione. This potentiation of the fruits' antioxidant system makes this composite coating a promising approach to keeping the postharvest quality of perishable fruits.

Plastid-expressed AdDjSKI enhances photosystem II stability, delays leaf senescence, and increases fruit yield in tomato plants under heat stress.

Heat stress substantially reduces tomato (Solanum lycopersicum) growth and yield globally, thereby jeopardizing food security. DnaJ proteins, constituents of the heat shock protein system, protect cells from diverse environmental stresses as HSP-70 molecular co-chaperones. In this study, we demonstrated that AdDjSKI, a serine-rich DnaJ III protein induced by pathogens, plays an important role in stabilizing photosystem II (PSII) in response to heat stress. Our results revealed that transplastomic tomato plants expressing the AdDjSKI gene exhibited increased levels of total soluble proteins, improved growth and chlorophyll content, reduced malondialdehyde (MDA) accumulation, and diminished PSII photoinhibition under elevated temperatures when compared with wild-type (WT) plants. Intriguingly, these transplastomic plants maintained higher levels of D1 protein under elevated temperatures compared with the WT plants, suggesting that overexpression of AdDjSKI in plastids is crucial for PSII protection, likely due to its chaperone activity. Furthermore, the transplastomic plants displayed lower accumulation of superoxide radical (O2 •─) and H2O2, in comparison with the WT plants, plausibly attributed to higher superoxide dismutase (SOD) and ascorbate peroxidase (APX) activities. This also coincides with an enhanced expression of corresponding genes, including SlCuZnSOD, SlFeSOD, SlAPX2, and SltAPX, under heat stress. Taken together, our findings reveal that chloroplastic expression of AdDjSKI in tomatoes plays a critical role in fruit yield, primarily through a combination of delayed senescence and stabilizing PSII under heat stress.

Variation in Nutritional Components and Antioxidant Capacity of Different Cultivars and Organs of Basella alba

Basella alba is a frequently consumed leafy vegetable. However, research on its nutritional components is limited. This study aimed to explore the variation in the nutritional components and antioxidant capacity of different cultivars and organs of Basella alba. Here, we primarily chose classical spectrophotometry and high-performance liquid chromatography (HPLC) to characterize the variation in nutritional components and antioxidant capacity among different organs (inflorescences, green fruits, black fruits, leaves, and stems) of eight typical cultivars of Basella alba. The determination indices (and methods) included the total soluble sugar (anthrone colorimetry), total soluble protein (the Bradford method), total chlorophyll (the ethanol-extracting method), total carotenoids (the ethanol-extracting method), total ascorbic acid (the HPLC method), total proanthocyanidins (the p-dimethylaminocinnamaldehyde method), total flavonoids (AlCl3 colorimetry), total phenolics (the Folin method), and antioxidant capacity (the FRAP and ABTS methods). The results indicated that M5 and M6 exhibited advantages in their nutrient contents and antioxidant capacities. Additionally, the inflorescences demonstrated the highest total ascorbic acid and total phenolic contents, while the green and black fruits exhibited relatively high levels of total proanthocyanidins and antioxidant capacity. In a comparison between the green and black fruits, the green fruits showed higher levels of total chlorophyll (0.77–1.85 mg g−1 DW), total proanthocyanidins (0.62–2.34 mg g−1 DW), total phenolics (15.28–27.35 mg g−1 DW), and ABTS (43.39–59.16%), while the black fruits exhibited higher levels of total soluble protein (65.45–89.48 mg g−1 DW) and total soluble sugar (56.40–207.62 mg g−1 DW) in most cultivars. Chlorophyll, carotenoids, and flavonoids were predominantly found in the leaves of most cultivars, whereas the total soluble sugar contents were highest in the stems of most cultivars. Overall, our findings underscore the significant influence of the cultivars on the nutritional composition of Basella alba. Moreover, we observed notable variations in the nutrient contents among the different organs of the eight cultivars, and proanthocyanidins may contribute significantly to the antioxidant activity of the fruits. On the whole, this study provides a theoretical basis for the genetic breeding of Basella alba and dietary nutrition and serves as a reference for the comprehensive utilization of this vegetable.

Rice husk ash based growing media impact on cucumber and melon growth and quality

Rice husk, an agricultural waste from the rice industry, can cause serious environmental pollution if not properly managed. However, rice husk ash (RHA) has been found to have many positive properties, making it a potential replacement for non-renewable peat in soilless planting. Thus, this study investigated the impact of a RHA composite substrate on the growth, photosynthetic parameters, and fruit quality of cucumber (Yuyi longxiang variety) and melon (Yutian yangjiaomi variety). The RHA, peat, vermiculite, and perlite were blended in varying proportions, with the conventional seedling substrate (peat:vermiculite:perlite = 1:1:1 volume ratio) serving as the control (CK). All plants were cultivated in barrels filled with 10L of the mixed substrates. The results from this study found that RHA 40 (RHA:peat:vermiculite:perlite = 4:4:1:1 volume ratio) significantly enhanced substrate ventilation and positively influenced the stem diameter, root activity, seedling index, chlorophyll content, net photosynthetic rate (Pn), stomatal conductance (Gs), and transpiration rate (Tr) of cucumber and melon plants. Additionally, plant planted using RHA 40, the individual fruit weight of cucumber and melon found to increase by 34.62% and 21.67%, respectively, as compared to the control. Aside from that, both cucumber and melon fruits had significantly higher sucrose, total soluble sugar, vitamin C, and soluble protein levels. This subsequently improved the activity of sucrose synthase and sucrose phosphate synthase in both cucumber and melon. In conclusion, the RHA 40 found to best promote cucumber and melon plant growth, increase plant leaf photosynthesis, and improve cucumber and melon fruit quality, making it a suitable substrate formula for cucumber and melon cultivation in place of peat.

Investigating the Interaction of Endophytic Bacteria and Biochemical Compounds in Pearl Millet (Pennisetum glaucum)

Pearl millet (Pennisetum glaucum) is an important cereal crop in Asia and Africa. This study focuses on quantifying endophytic bacteria in several parts of the pearl millet plant—roots, stems, and leaves. Total phenolic content, orthodihydroxy phenols, total soluble sugars, protein levels, and enzymatic activity (peroxidase, polyphenol oxidase, and catalase) were all measured and linked with the amount of endophytic bacteria. The leaves have the highest total phenolic content, followed by the stem. Orthodihydroxy phenols were also significantly greater in leaves (1.82 mg catechol equi./g) than in stems and roots. Total soluble sugars showed higher levels in leaves (9.97 mg glucose equi./g), in stems (9.21 mg glucose equi./g) and in roots ( 6.83 mg glucose equi./g). Protein content exhibited significant variation among the plant parts, with leaves (10.63%) containing the highest protein content followed by stems and roots (8.47% and 6.67% respectively). Enzymatic activities, crucial for plant defence and growth, varied across the plant sections. Peroxidase activity was highest in roots (359.98 OD/g), followed by stems and leaves. Polyphenol oxidase activity was lowest in the roots (1.63 OD/g) and highest in the leaves with 2.19 OD/g, while catalase activity was the highest activity in the roots with 17.79 OD/g versus 14.79 OD/g and 14.63 OD/gin the leaves and Roots respectively. The number of Pearl millet endophytic bacteria in the roots is 16, whereas the amount in the stem is 12 and 10 in the leaves. This in-depth analysis sheds light on future research targeted at better understanding plant-microbe interactions and developing ways to improve plant health and productivity.

Copper nanoparticles alleviate cadmium stress in Solanum melongena through endogenous melatonin and regulation of some physiochemical attributes

Different chemicals and substances are often used to increase plant growth and production, and their efficacy is impacted by things like concentration and growth stage. This study aimed to investigate the impact of cadmium (Cd) stress on Solanum melongena L. and evaluate the potential alleviating effects of Cu-nanoparticles. The findings revealed that low concentrations of Cu-nanoparticles effectively protected S. melongena. from the adverse effects of heavy metal stress. Cu-nanoparticles exhibited a crucial role in plant physiology by stimulating enzyme activity and defense mechanisms. Furthermore, moderate concentrations of Cu-nanoparticles were observed to promote plant growth and increase chlorophyll content. Additionally, the treatments with low concentrations of Cu-nanoparticles resulted in reduced oxidative stress, as evidenced by decreased levels of hydrogen peroxide and malondialdehyde (MDA) content. Moreover, the application of Cu-nanoparticles positively influenced total soluble protein levels and relative water content. Furthermore, the Cu-nanoparticles treatment effectively alleviated Cd-induced oxidative stress and increased the concentration of melatonin. Antioxidant accumulation exhibited an increase under various treatments, with the moderate concentration of Cu-nanoparticles showing the most favorable impact. In conclusion, the moderate concentration of Cu-nanoparticles demonstrated promising effects in mitigating Cd-induced stress and optimizing the growth and physiology of S. melongena plants.

Production of L-lysine under submerged fermentation by <i>Corynebacterium glutamicum</i> using different agricultural plants leaves

Introduction: This study investigated the production of L-lysine using Corynebacterium glutamicum and various leaf extracts (cassava, palm tree, maize, cowpea, cocoyam, and plantain). The study also explored the activities of amylases and proteases, as well as the levels of total soluble proteins, reducing sugars, glucose, flavonoid and phenolic contents, and pH changes.
 Materials and Methods: Different treatments (extract, boiled extract, extract + C. glutamicum, boiled extract + C. glutamicum) were examined for their effects on L-lysine concentration. Additionally, the activities of amylases and proteases, as well as levels of total soluble proteins, reducing sugars, glucose, flavonoid and phenolic contents, and pH changes, were analyzed.
 Results: Maize leaf extract + C. glutamicum exhibited the highest L-lysine concentration (1.771a±0.1 mg/g), while boiled cassava leaf extract showed the lowest concentration (0.023b±0.1 mg/g). Palm tree leaf extract had significantly higher reducing sugar levels compared to other extracts. Boiled plantain leaf extract fermented by C. glutamicum had the highest total soluble protein level (9.5±0.2 mg/g), while cassava leaf extract had the lowest (2.1±1.2 mg/g).
 Conclusion: Submerged fermentation of leaf extracts using C. glutamicum can be utilized for L-lysine production. The study highlights the influence of different leaf extracts and treatments on L-lysine production, as well as on amylase and protease activities, total soluble protein levels, reducing sugars, glucose, flavonoid and phenolic contents, and pH values. These findings provide valuable insights into the potential application of this approach for lysine production.

Investigating the efficacy of tartaric acid and zinc-mediated endogenous melatonin induction for mitigating arsenic stress in Tagetes patula L.

In order to enhance plant growth and productivity, various chemicals and substances are commonly employed, wherein their effectiveness is influenced by factors such as concentration and growth stage. This study aimed to investigate the impact of arsenic stress on Tagetes patula L. and evaluate the potential alleviating effects of zinc (Zn) and tartaric acid. The findings revealed that low concentrations of Zn and tartaric acid effectively protected Tagetes patula L. from the adverse effects of heavy metal stress. Zinc exhibited a crucial role in plant physiology by stimulating enzyme activity and defense mechanisms. Furthermore, moderate concentrations of Zn and tartaric acid were observed to promote plant growth and increase chlorophyll content. Notably, the combined application of Zn and tartaric acid exhibited the most significant improvements in plant morphology and chlorophyll levels. Additionally, the treatments with low concentrations of Zn and tartaric acid resulted in reduced oxidative stress, as evidenced by decreased levels of hydrogen peroxide and malondialdehyde (MDA) content. Moreover, the application of zinc and tartaric acid positively influenced total soluble protein levels and relative water content. The combined treatment also enhanced the activities of antioxidant enzymes, thereby mitigating oxidative damage induced by arsenic stress. Furthermore, the synergistic effect of the Zn and tartaric acid treatment effectively alleviated arsenic-induced oxidative stress and increased the concentration of melatonin. Proline accumulation exhibited an increase under various treatments, with the combination of Zn and tartaric acid showing the most favorable impact. The resting membrane potential (RMP) of the plants was influenced by different treatments, with consistent effects observed in the combined Zn and tartaric acid treatment. Additionally, the combination of targeted amendments (TA) and Zn treatments proved beneficial in reducing soil pollution indicators. In conclusion, the synergistic application of Zn and tartaric acid demonstrated promising effects in mitigating arsenic-induced stress and optimizing the growth and physiology of Tagetes patula plants.

Antireproductive changes instigated by efficient drug delivery via papaya seed chloroform extract-based nanoparticles in male rat Bandicota bengalensis

Anti-reproductive potential of papaya seed chloroform extract-based solid lipid nanoparticles (PSCEN) was investigated for the first time in lesser bandicoot rat, Bandicota bengalensis. Mature male rats (n = 30 per group) were fed bait (loose mixture of cracked wheat, powdered sugar, and groundnut oil in the ratio 88:10:2) containing two different concentrations of PSCEN (5% and 10%) in a bi-choice condition for 15 days with one group as vehicle control. The ingestion of active ingredient in 15 days treatment was significantly (P ≤ 0.05) higher by rats treated with 10% PSCEN (39.17–58.70 g/kg body weight) as compared to rats treated with 5% PSCEN (21.30–33.23 g/kg body weight). A dose dependent significant (P ≤ 0.05) decrease was observed in the level of testosterone, FSH, LH and GnRH in plasma of treated rats. A significant (P ≤ 0.05) decrease was also observed in level of total soluble proteins, total lipids, phospholipids and cholesterol in both plasma and testicular tissue, and level of 17β-HSD and 3β-HSD in testicular tissue indicating anti-reproductive effects of PSCEN treatment. There was observed significant (P ≤ 0.05) effect of treatment on histomorphology of testis and cauda epididymis in the form of reduced tubular diameter, germinal epithelial thickness, number of germ cells and dissociation of epithelial cycle in seminiferous tubules, and reduced tubular diameter, increased epithelial thickness, vacuolization, loose contact of principle cells and reduced number of spermatozoa in the cauda epididymal tubules. Maximum antifertility effect was observed with 10% PSCEN treatment, which was not reversed upto 105 days of treatment withdrawal indicating long-term efficacy. The current investigation suggests the use of PSCEN in the management of reproduction of B. bengalensis by exerting influence on testicular and cauda epididymal functions and biochemical parameters.

Glutathione primed seed improved lead-stress tolerance in Brassica rapa L. through modulation of physio-biochemical attributes and nutrient uptake

Heavy metal toxicity is a major environmental issue that affects all life forms, including plants. The accumulation of lead (Pb) in agricultural soils is a significant contributor to reduced crop yields, and it poses serious health risks to people who consume lead-contaminated agricultural products. The current study was undertaken to investigate the beneficial effects of glutathione (GSH) on the amelioration of stress induced by Pb (300 mg kg−1 Pb) in Brassica rapa L. (turnip). For this purpose, B. rapa seeds primed with 25, 50, and 75 µmol L−1. The root and shoot length, seedling biomass, and leaf area, was reduced under Pb stress. Lead toxicity inhibited the net photosynthetic rate (31.36%), total chlorophyll content (74.54%) of B. rapa plants in comparison to control. Lead-stressed plants additionally exhibited changes in proline levels, as well as lower levels of total soluble protein and phenolic content. Nevertheless, seed priming with GSH resulted in higher concentrations of the nutritional content (Mg+2, Zn+2, Na+, K+) that increased Pb stress tolerance. The GSH2 treated seed enhanced the photosynthetic rate (46.34%), stomatal conductance (80.55%), and transpiration rate (53.125%) over Pb stress. Furthermore, GSH2 enhanced total soluble proteins (37.75%), phenolic content (58.38%), and DPPH (1.5fold) of turnip plant over control seedlings. According to our research, GSH2 primed B. rapa seed demonstrated a reduction in Pb toxicity, which could be used to help seedling establishment in soils contaminated with Pb.

Silicon-Induced Mitigation of NaCl Stress in Barley (Hordeum vulgare L.), Associated with Enhanced Enzymatic and Non-Enzymatic Antioxidant Activities.

Salt stress obstructs plant’s growth by affecting metabolic processes, ion homeostasis and over-production of reactive oxygen species. In this regard silicon (Si) has been known to augment a plant’s antioxidant defense system to combat adverse effects of salinity stress. In order to quantify the Si-mediated salinity tolerance, we studied the role of Si (200 ppm) applied through rooting media on antioxidant battery system of barley genotypes; B-10008 (salt-tolerant) and B-14011 (salt-sensitive) subjected to salt stress (200 mM NaCl). A significant decline in the accumulation of shoot (35–74%) and root (30–85%) biomass was observed under salinity stress, while Si application through rooting media enhancing biomass accumulation of shoots (33–49%) and root (32–37%) under salinity stress. The over-accumulation reactive oxygen species i.e., hydrogen peroxide (H2O2) is an inevitable process resulting into lipid peroxidation, which was evident by enhanced malondialdehyde levels (13–67%) under salinity stress. These events activated a defense system, which was marked by higher levels of total soluble proteins and uplifted activities of antioxidants enzymatic (SOD, POD, CAT, GR and APX) and non-enzymatic (α-tocopherol, total phenolics, AsA, total glutathione, GSH, GSSG and proline) in roots and leaves under salinity stress. The Si application through rooting media further strengthened the salt stressed barley plant’s defense system by up-regulating the activities of enzymatic and non-enzymatic antioxidant in order to mitigate excessive H2O2 efficiently. The results revealed that although salt-tolerant genotype (B-10008) was best adopted to tolerate salt stress, comparably the response of salt-sensitive genotype (B-14011) was more prominent (accumulation of antioxidant) after application of Si through rooting media under salinity stress.

Induction of Systemic Resistance to Tobacco mosaic virus in Tomato through Foliar Application of Bacillus amyloliquefaciens Strain TBorg1 Culture Filtrate.

The application of microbe-derived products as natural biocontrol agents to boost systemic disease resistance to virus infections in plants is a prospective strategy to make agriculture more sustainable and environmentally friendly. In the current study, the rhizobacterium Bacillus amyloliquefaciens strain TBorg1 was identified based on 16S rRNA, rpoB, and gyrA gene sequences, and evaluated for its efficiency in conferring protection of tomato from infection by Tobacco mosaic virus (TMV). Under greenhouse circumstances, foliar sprays of TBorg1 culture filtrate (TBorg1-CF) promoted tomato growth, lowered disease severity, and significantly decreased TMV accumulation in systemically infected leaves of treated plants relative to untreated controls. TMV accumulation was reduced by 90% following the dual treatment, applied 24 h before and after TMV infection. Significant increases in levels of total soluble carbohydrates, proteins, and ascorbic acid were also found. In addition, a significant rise in activities of enzymes capable of scavenging reactive oxygen species (PPO and POX), as well as decreased levels of non-enzymatic oxidative stress markers (H2O2 and MDA) were observed, compared to untreated plants. Enhanced systemic resistance to TMV was indicated by significantly increased transcript accumulation of polyphenolic pathway (C4H, HCT, and CHI) and pathogenesis-related (PR-1 and PR-5) genes. Out of the 15 compounds identified in the GC-MS analysis, 1,2-benzenedicarboxylic acid mono(2-ethylhexyl) ester and phenol, 2,4-bis(1,1-dimethylethyl), as well as L-proline, N-valeryl-, and heptadecyl ester were present in the highest concentrations in the ethyl acetate extract of TBorg1-CF. In addition, significant amounts of n-hexadecanoic acid, pyrrolo [1,2-a] pyrazine-1,4-dione hexahydro-3-(2-methylpropyl)-, nonane, 5-butyl-, and eicosane were also detected. These compounds may act as inducers of systemic resistance to viral infection. Our findings indicate that the newly isolated B. amyloliquefaciens strain TBorg1 could be a potentially useful rhizobacterium for promoting plant growth and a possible source of biocontrol agents for combating plant virus infections.

Potential of Saturnispora diversa MA as a postharvest biocontrol agent against anthracnose in loquat fruit

A yeast strain (MA) was isolated from mango fruitand found to inhibit Colletotrichum gloeosporioides. The MA strain was subsequently identified as Saturnispora diversa based on 18S rRNA sequencingand a phylogenetic analysis. S. diversa, strain MA, effectively inhibited the growth and spore germination of C. gloeosporioides through competition of nutrients and space, as well as its ability to adhere to developing hyphae and spores of C. gloeosporioides. The inhibitory activity of MA was concentration dependent and increased as the concentration of MA was increased. Relative to the untreated control, fruit treated with S. diversa MA had a lower disease index and browning index, retained a higher degree of fruit firmness, and had increased levels of total soluble solids and protein, resulting in higher postharvest quality. S. diversa MA treatment decreased the accumulation of malondialdehyde (MDA) in loquat fruit, the generation superoxide anion (O2–.), and electrolyte leakage (an indicator of membrane injury). MA also enhanced the reactive oxygen species (ROS) scavenging enzyme activity, induced the activity of peroxidase (POD), and polyphenol oxidase (PPO), chitinase (CHI), all of which enhanced the disease resistance of loquat fruit to C. gloeosporioides. Our results demonstrate that S. diversa MA inhibits C. gloeosporioides and maintains the postharvest quality of loquat fruit. Based on these findings S. diversa MA represents an effective biocontrol agent that could be used to manage postharvest anthracnose in loquat.

Characterization of mucilage from clones of Opuntia and Nopalea prickly pear cactus harvested in different seasons in Brazilian semiarid

This study proposes to characterize hydrated and refrigerated mucilage obtained from cladodes of clones of prickly pear cactus harvested during the drizzle and dry seasons in the semiarid of Brazil. Cladodes of Opuntia stricta [Haw.] Haw (Orelha de Elefante Mexicana [OEM] clone) and Nopalea cochenillifera Salm Dyck (IPA Sertânia [IPA] and Miúda [MIU] clones) were harvested at 6 am and extracted mucilage. The main bands in the infrared region were characterized. Physicochemical analyses were performed on day zero and at 12 days. Cladodes harvested in the dry season showed higher mucilage yield and soluble solid, total soluble carbohydrate, and K+, for the three clones. The OEM clone also exhibited significant increases in pH, Na+, and electrical conductivity when harvested in the dry season than in the wet season. In addition, the mucilage extracted from the Opuntia cladodes did not have changes in the carbohydrate, titratable acidity, or total soluble protein levels. The IPA and MIU clones, in turn, were characterized by parameters that remained stable during conservation (phenolic compounds, titratable acidity, K+ and Na+). The spectroscopic profile was similar for all studied clones. The principal component analysis allowed the formation of clusters between seasons and conservation times. It is suggested that the cladodes of the genus Nopalea showed better potential in the manufacture of edible films and coatings. The cladodes of the genus Opuntia, for the use of mucilage as ingredients in foods such as bread, pasta, and others, making them with better functional properties. Therefore, these factors should be considered for the use of mucilage in the industry.

Biochar coupling with phosphorus fertilization modifies antioxidant activity, osmolyte accumulation and reactive oxygen species synthesis in the leaves and xylem sap of rice cultivars under high-temperature stress.

Increasing temperature poses a serious threat to rice productivity. This study investigated the impact of various biochar treatments and phosphorous (P) fertilization on osmolyte accumulation, ROS development, and antioxidant activity in two rice cultivars (IR-64 and Huanghuazhan) under high-temperature stress. All plants of both cultivars were grown in a controlled environment under ambient temperatures (AT), high day temperatures (HDT) or high night temperatures (HNT). The different fertilization treatments were biochar alone, P alone and biochar + Pwith control. In the leaves and xylem sap of both rice cultivars, particularly in the susceptible cv. IR-64, high-temperature stress increased the production of MDA and H2O2. HDT and HNT decreased total soluble sugars, protein, and proline levels in both rice cultivars. HNT was observed asmore harmful compared to HDT during most of the studied characteristics. The response of antioxidant enzyme activities, viz, SOD, POD, CAT, APX, ASC, GSH, GR, and GSSC activities, to the temperature treatments varied between the two cultivars. Antioxidant activities decreased in the leaves and xylem sap of IR-64 but increased in those of Huanghuazhan upon exposure to high-temperature stress. Huanghuazhan exhibited better heat tolerance compared to IR-64, which was linked to its increased antioxidant enzyme activation and metabolite synthesis. As compared to the control, all soil fertilization treatments considerably reduced the adverse impacts of high temperature on the rice cultivars. The combination of biochar and P resulted in better performance compared to the other treatments in terms of all studied attributes.

Quantitative Determination of the Effects of He–Ne Laser Irradiation on Seed Thermodynamics, Germination Attributes and Metabolites of Safflower (Carthamus tinctorius L.) in Relation with the Activities of Germination Enzymes

The present investigation was undertaken to assess the effects of different doses (100, 300, and 500 mJ) of low power He–Ne laser (632.8 nm) irradiation on seed germination and thermodynamics attributes and activities of potential germinating enzymes in relation with changes in seed metabolites. He–Ne laser seed irradiation increased the amylase (Amy), protease (Pro) and glucosidase (Gluco) activities, with a significant improvement in seed thermodynamics and seed germination attributes. A fast increase was found in free fatty acids (FFA), free amino acids (FAA), chlorophyll (Chl), carotenoids (Car), total soluble sugars (TSS) and reducing sugars (RS) in laser treated seeds in parallel with fast decline in seed oil contents and total soluble proteins (TSP). Significant positive correlations were recorded in laser-induced enhanced seed energy levels, germination, activities of germination enzymes with levels of FAA, FFA, Chl, TSS and RS, but a negative correlation with the levels of TSP and oil. In conclusion, the seed treatment with 100 and 300 mJ He–Ne laser was more effective to improve the seed germination potential associated with an improvement in seed energy levels due to increased activities of germination enzymes due to the speedy breakdown of seed reserves to simple metabolites as building blocks.

Biochemical changes in black oat plants in response to water deficit under different temperatures

The black oat (Avena strigosa Schreb.) stands out as a forage of great importance in Brazilian agriculture. However, the productivity and quality of this forage can be affected by abiotic factors, such as temperature and water availability, which affect the physiological processes and facilitate the accumulation of free radicals (reactive oxygen species - ROS). Thus, the objective of this study was to understand the biochemical changes in black oat plants subjected to water deficit at different temperatures. Experiments were conducted in a greenhouse in two experimental periods, which presented an average temperature of 20 °C and 24 °C, respectively. Black oat seeds, of the variety IAPAR 61, were sown in pots and the plants were irrigated for 60 days. After which, the pots were covered with plastic bags and the irrigation was suspended. The analyses were carried out in five periods of evaluation - M1: plants before the suspension of irrigation, M2: plants at the first wilting point, M3: three days after plastic removal and irrigation return, M4: four days after M3 and before the second suspension of irrigation, and M5: the second wilting point. The levels of total protein and malondialdehyde (MDA), and the activity of the enzymes catalase (CAT) and ascorbate peroxidase (APX), were analyzed. The experimental design was completely randomized, with six replications, in a factorial scheme of average temperature × water management × periods of evaluation, and the means were compared by Tukey’s test at 5%. In response to water deficiency and temperature increase, black oat plants increased their levels of total soluble proteins, and there was greater lipid peroxidation due to the increase in malondialdehyde content. There was no change in the activity of the enzymes catalase and ascorbate peroxidase under water deficit, and these activities decreased with increasing temperature.