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Chromium (Cr) toxicity significantly threatens sunflower growth and productivity by interfering with enzymatic activity and generating reactive oxygen species (ROS). Zinc quantum dot biochar (ZQDB) and arbuscular mycorrhizal fungi (AMF) have become popular to resolve this issue. AMF can facilitate root growth, while biochar tends to minimize Cr mobility in soil. The current study aimed to explore AMF and ZQDB combined effects on sunflower plants in response to Cr toxicity. Four treatments were applied, i.e. NoAMF + NoZQDB, AMF + 0.40%ZQDB, AMF + 0.80%ZQDB, and AMF + 1.20%ZQDB, under different stress levels of Cr, i.e. no Cr (control), 150 and 200 mg Cr/kg soil. Results showed that AMF + 1.20%ZQDB was the treatment that caused the greatest improvement in plant height, stem diameter, head diameter, number of leaves per plant, achenes per head, 1000 achenes weight, achene yield, biological yield, transpiration rate, stomatal conductance, chlorophyll content and oleic acid, relative to the condition NoAMF + No ZQDB at 200 mg Cr/kg soil. A significant decline in peroxidase (POD), superoxide dismutase (SOD), and catalase (CAT) while improvement in ascorbate peroxidase (APx), oil content, and protein content further supported the effectiveness of AMF + 1.20%ZQDB against Cr toxicity. Our results suggest that the treatment AMF + 1.20%ZQDB can efficiently alleviate Cr stress in sunflowers. [ABSTRACT FROM AUTHOR]

Background: Medicinal plants harboring endophytic fungi could carry significant potential for producing bioactive secondary metabolites. Endophytic fungi serve as alternate source of interesting compounds in their natural and modified synthetic forms to treat different diseases. In this regard, endophytic microflora associated with alkaloid-rich medicinal plants Rhazya stricta is least known. Results: We isolated one new bioactive compound sorokiniol (1) along with two known cyclic peptides BZR-cotoxin I (2) and BZR-cotoxin IV (3) from fungal endophyte Bipolaris sorokiniana LK12. The structures of the isolated new and known compounds were elucidated through spectroscopic data, including 1D and 2D NMR (1H, 13C, HSQC, HMBC, and NOESY), mass, and UV. The known peptides (2-3) were characterized by ESI-MS, MS/MS, and by comparing the NMR data with the literature. The isolated metabolites were assayed for their role against enzyme inhibition. Compound 1 was significantly inhibitory towards acetyl cholinestrase while the other compounds (2–3) had moderate anti-lipid peroxidation and urease activities. Conclusion: The present results suggest that the endophytic microorganism associated with indigenously important medicinal plants can offer a rich source of biologically active chemical constituents which could help in discovering enzyme inhibitory lead drugs. [ABSTRACT FROM AUTHOR]

Antioxidants are the substances which significantly delay or prevent the development of age-related degenerative and chronic diseases caused by oxidative damage. Due to this, there is a considerable interest in the identification of lead molecules, which can inhibit the oxidation process or slow it down considerably. Based on the spectrofluorimetric analysis of superoxide and diphenylpicrylhydrazyl radical scavenging ability, the bio-assay guided isolation of methanolic extract of Nepeta floccosa Benth. was carried out. As a result of this study, one new flavanonol named nepetavanol (1) and four known flavonoids; dihydrokaempferol (2), naringenin (3), caulesnarinside (4), and poncirin (5) have been isolated. The structure of the new flavanonol was assigned on the basis of ¹H- and 13C-NMR spectra including two-dimensional NMR techniques such as COSY, HMQC, and HMBC experiments and FABMS, EIMS, HR-MS data. Compound 1, 2, and 3 showed significant activity whereas compounds 4 and 5 showed moderate activity against antioxidant assays. [ABSTRACT FROM AUTHOR]

Purpose: To evaluate antiglycation and antioxidant activities as undertake HPTLC analysis of Boswellia sacra resin. Methods: Sub-fractionation of the crude methanol extract of Hougari regular (HR) grade resin of Boswellia sacra was carried out by vacuum liquid chromatography. Free radical scavenging and antiglycation activities of sub-fractions were characterized in order to assess their anti-aging properties. Furthermore, high performance thin layer chromatography (HPTLC) analysis of Boswellia sacra resins was also carried out. Results: Polar fractions of the extract obtained exhibited the highest antiglycation activity while nonpolar fractions showed more than 50 % inhibition in superoxide anion scavenging assay. Scavenging activity of reactive oxygen species results indicate that non-polar sub-fractions showed > 50 % inhibition, except Shabi frankincense (SF) oil which showed 33 % inhibition. Dichloromethane (CH2Cl2) fraction, 40 % dichloromethane (CH2Cl2)/n-hexane sub-fraction, and SF oil showed moderate activity in di(phenyl)-(2,4,6-trinitrophenyl)iminoazanium (DPPH) assay. Furthermore, HPTLC analysis indicates the presence of 11-keto-ß-boswellic acid (KBA) and 3-O-acetyl-11-keto-ß-boswellic acid (AKBA) along with some other terpenoids. Conclusion: Various sub-fractions of Boswellia sacra exert effective antiglycation and antioxidant activities. The extracts should be studied further for possible formulation into pharmaceutical products. [ABSTRACT FROM AUTHOR]

Abstract: Late season production of raspberries and blackberries has become more common due to increased consumer demand and new production techniques, but information is scarce regarding the effect on nutritional quality, especially during storage. Antioxidant levels in berries can be influenced by pre-harvest climate conditions (light intensity, day length and temperature) and post-harvest storage time. This study analysed the effect of these factors on the content of different antioxidants (vitamin C, ellagic acid, anthocyanins and total phenolics) in raspberries (Rubus idaeus L. cv. Polka) and blackberries (Rubus fructicosus L. cv. Loch Ness) during storage. The analyses were performed using high performance liquid chromatography (HPLC) with photodiode array detection. Ellagic acid content during storage ranged between 104 and 114mg/100g fresh weight in raspberries and 172 and 182mg/100g fresh weight in blackberries. Anthocyanin content increased during storage from 64 to 77mg/100g fresh weight in raspberries, but decreased from 199 to 162mg/100g fresh weight in blackberries. Vitamin C content in raspberries ranged during storage between 22 and 28mg/100g fresh weight, but in blackberries values were lower (10–12mg/100g fresh weight). Significant changes in total phenolics and sugars occurred during different storage periods (0–9 or 10 days). The results suggest that late season raspberries and blackberries maintain high quality in terms of antioxidant content. [Copyright &y& Elsevier]

Globally, salinity is an important abiotic stress in agriculture. It induced oxidative stress and nutritional imbalance in plants, resulting in poor crop productivity. Applying silicon (Si) can improve the uptake of macronutrients. On the other hand, using biochar as a soil amendment can also decrease salinity stress due to its high porosity, cation exchange capacity, and water-holding capacity. That's why the current experiment was conducted with novelty to explore the impact of silicon nanoparticle-based biochar (Si-BC) on wheat cultivated on salt-affected soil. There were 3 levels of Si-BC, i.e., control (0), 1% Si-BC1, and 2.5% Si-BC2 applied in 3 replicates under 0 and 200 mM NaCl following a completely randomized design. Results showed that treatment 2.5% Si-BC2 performed significantly better for the enhancement in shoot and root length, shoot and root fresh weight, shoot and root dry weight, number of leaves, number of tillers, number of spikelets, spike length, spike fresh and dry weight compared to control under no stress and salinity stress (200 mM NaCl). A significant enhancement in chlorophyll a (~ 18%), chlorophyll b (~ 22%), total chlorophyll (~ 20%), carotenoid (~ 60%), relative water contents (~ 58%) also signified the effectiveness of treatment 2.5% Si-BC2 than control under 200 mM NaCl. In conclusion, treatment 2.5% Si-BC2 can potentially mitigate the salinity stress in wheat by regulating antioxidants and improving N, K concentration, and gas exchange attributes while decreasing Na and Cl concentration and electrolyte leakage. More investigations at the field level are recommended for the declaration of treatment 2.5% Si-BC2 as the best amendment for alleviating salinity stress in different crops under variable climatic conditions. [ABSTRACT FROM AUTHOR]

Recently many lethal diseases are caused by oxidative stress. The accumulation of reactive species, including ROS and reactive nitrogen species, can be harmful to human health, as they can attack cells and tissues within the body, causing several diseases. Antioxidants are therefore needed exogenously by the body. Numerous antioxidant-based products are commercially available but have side effects. The plantbased natural antioxidants are preferred over synthetic antioxidants. Natural antioxidants are cost-effective as well as environmentally friendly. Araucaria heterophylla is a well-known medicinal plant in the family Araucariaceae. The major component of these species is known as carbohydrates-rich gum which possesses antioxidant, antimicrobial, antipyretic, neuroprotective, anticoagulant, and antiviral activities. Therefore, the main objective of the current study was to investigate the time and concentration-dependent antioxidant potential in the gum of Araucaria heterophylla. Here, four different concentrations (2.5, 5.0, 7.5, and 10mg/10mL) were tested for antioxidant activity. The dose-dependent and time-dependent (05, 10, 15, 20, 25, 30, 35, 45, 50, 55, 60, 65, and 70min) activities displayed variation in antioxidant potential. The gum extract (10mg/10mL) of Araucaria heterophylla showed the highest activity (89%) after 60min incubation. However, the other concentrations (2.5-7.5mg/10mL) exhibited 31, 66, and 88% activities. These results suggest that the antioxidant activity is strongly dependent on incubation time and concentration. Hence the gum of Araucaria heterophylla is an excellent source of natural antioxidants and can be used by food and pharmaceutical industries for various human diseases. [ABSTRACT FROM AUTHOR]

High soil boron (B) concentrations in arid and semi-arid regions of the world are responsible for decreased crop productivity. However, the use of plant growth promoting rhizobacteria (PGPR) can improve the plant growth under stress conditions like high B either due to limited uptake of B or enhanced antioxidants production, as PGPR have been shown to enhance the resistance in plants against various abiotic stresses. A pot experiment was conducted under green house conditions according to completely randomized design (CRD) and comprised of four levels of B (0.45, 10, 20, and 50 mg B kg −1 soil) either with or without PGPR. Plants were grown for 10 weeks after onset of experiment and analyzed for mineral composition including B and antioxidation activity. Shoot fresh weight, shoot dry weight and leaf chlorophyll contents were inhibited to increasing levels of B. Interestingly, shoot K + concentration tended to increase with increasing B levels, particularly at 50 mg B kg −1 soil; third level of B (B3). Similarly, highest shoot B concentrations were observed at high levels of B supply (B3) as compared to all other treatments. Likewise, with the increase in external B supply, antioxidant enzymes activities and proline contents in tomato shoot were enhanced. Bacillus pumilus inoculation significantly improved the shoot fresh weight and dry weight of unstressed (control) as well as B-stressed plants. In general, B. pumilus inoculation enhanced the plant antioxidation activity, particularly superoxide dismutase (SOD) and catalase (CAT) antioxidant enzymes. Contrary, the interaction between high B and B. pumilus remained insignificant for limiting the shoot B uptake except for second level of B (B2) which decreased the shoot B accumulation by 21% as compared to non-inoculated B2 . Our results suggest that PGPR inoculation confer tolerance in B-stressed plants through the induced plant antioxidation activity. Additionally, PGPR inoculation reduces the shoot B accumulation, however, differential response of shoot B inhibition is expected to increasing B concentrations. [ABSTRACT FROM AUTHOR]

Quercetin is a well-known flavonoid that has been listed as ingredient in many supplements, beverages and foods for a long time. The use of quercetin has been widely associated with a great number of health benefits such as antioxidant, anti-inflammatory, antiviral and anticancer as well as to ease some cardiovascular diseases such as heart disease, hypertension, and high blood cholesterol. In this study, fluorescence emission spectroscopy coupled with partial least square regression (PLSR) was used for the estimation of quercetin in different fractions of Euphorbia masirahensis and the obtained results were cross validated by UV–visible spectroscopy. Different fraction of methanol extract of dried plant material were subjected to emission spectroscopic analysis, followed by PLS regression . The results indicated that n -butanol fraction contained the higher quercetin contents i.e. (5.83 ± 0.09%) followed by ethyl acetate fraction i.e. (4.25 ± 0.06%). The method was parallel cross validated with UV–visible spectroscopy. The results from both methods were found to be very consistent but the fluorescence-PLSR method was found to be of higher accuracy due to its high sensitivity with slope value of 0.99 and RMSE vlues of 0.36%. This emission spectroscopic method coupled with PLSR is sensitive, reproducible, simple, eco-friendly and non-destructive. [ABSTRACT FROM AUTHOR]

Flavonoids are natural antioxidants derived from plants and commonly found in a variety of foods to sequester free radicals. Quercetin, belonging to flavonol subclass of flavonoids, has received considerable attention because of its wide uses as a nutritional supplement as well as a phytochemical remedy for a number of diseases. In the current study, quantification of quercetin was carried out in two medicinally important flavonoid rich plant Ziziphus mucronata and Ziziphus sativa . Emission spectroscopy was utilized as a new method coupled with Partial Least Squares Regression (PLSR) and the cross validation was done by UV–Visible spectroscopy. The results indicated the higher quercetin content in Z. mucronata (1.50 ± 0.034%) than Z. sativa (1.21 ± 0.052%), and were further verified through Folin-Ciocalteu Colorimetric method ( Z. mucronata; 1.41 ± 0.26% and Z. sativa ; 1.13 ± 0.136%). In this study the sensitivity was explained in term of slope i.e. Slope = 0.9973. [ABSTRACT FROM AUTHOR]