Screening herbal extracts as biostimulant to increase germination, plant growth and secondary metabolite production in wheatgrass.

Recently it has been recognized that herbal plants contain endogenous molecules with biostimulant properties, capable of inducing morphological and biochemical changes in crop plants. Therefore, the present experiment was conducted to screen herbal samples for their plant growth promoting properties. Twenty-five herbal extracts were tested for their biostimulating activity on wheat crop (Triticum aestivum) through seed priming. Morphological parameters chosen for evaluation include: percent seed germination, length and weight of seedling, wheat grass length and biomass. Biochemical parameters include: total phenolic and flavonoid, enzymatic activity of catalase and phenylalanine ammonium lyase and antioxidant activity. Results indicated an increase in the tested parameters by the extracts, however the biostimulant property varied between the selected herbal samples. Some of the samples, such as Phyllanthus emblica, Plumbago zeylanica, Catharanthus roseus and Baccopa monnieri, were highly effective in inducing plant growth promoting parameters. Principal component analysis was performed and herbal samples were grouped into categories based on their activity.

Effect of exogenous phytohormone treatment on antioxidant activity, enzyme activity and phenolic content in wheat sprouts and identification of metabolites of control and treated samples by UHPLC-MS analysis.

Phytohormones, Indole acetic acid, Salicylic acid and Gibberellic acid, either alone or in combination was applied on wheat sprouts to improve its nutritional status. The experiment included estimation of total phenolic, flavonoids, peroxidase activity and phenylalanine ammonium lyase activity. Antioxidant activity was determined by DPPH and FRAP assay. The results showed an increase in phenolic compounds, enzyme activity and antioxidant activity after treatment with the phytohormones. Phytohormone combinations were found to be more effective as compared to pure treatments. UHPLC-ESI-MS analysis was used to identify compounds in the control and treated samples. Phenolic acids, polyphenols, simple sugars, amino acids, dipeptides, lipids and fatty acids were detected. A multifold increase in the levels of phenolic compounds was observed in the phytohormone treated wheat sprouts.

Distribution profile of iridoid glycosides and phenolic compounds in two Barleria species and their correlation with antioxidant and antibacterial activity.

Introduction: Barleria prionitis is known for its medicinal properties from ancient times. Bioactive iridoid glycosides and phenolic compounds have been isolated from leaves of this plant. However, other parts of a medicinal plants are also important, especially roots. Therefore, it is important to screen all organs for complete chemical characterization. Method: All parts of B. prionitis, including leaf, root, stem and inflorescence in search of bioactive compounds, with a rapid and effective metabolomic method. X500R QTOF system with information dependent acquisition (IDA) method was used to collect high resolution accurate mass data (HRMS) on both the parent (MS signal) and their fragment ions (MS/MS signal). ESI spectra was obtained in positive ion mode from all parts of the plant. A comparative analysis of antioxidant and antibacterial activity was done and their correlation study with the identified compounds was demonstrated. Principal component analysis was performed. Result: Iridoid glycosides and phenolic compounds were identified from all parts of the showing variability in presence and abundance. Many of the compounds are reported first time in B. prionitis. Antioxidant and antibacterial activity was revealed in all organs, root being the most effective one. Some of the iridoid glycoside and phenolic compounds found to be positively correlated with the tested biological activity. Principal component analysis of the chemical profiles showed variability in distribution of the compounds. Conclusion: All parts of B. prionitis are rich source of bioactive iridoid glycosides and phenolic compounds.

Enhancing phytochemical levels, enzymatic and antioxidant activity of spinach leaves by chitosan treatment and an insight into the metabolic pathway using DART-MS technique.

Phytochemicals are health promoting compounds, synthesized by the plants to protect them against biotic or abiotic stress. The metabolic pathways leading to the synthesis of these phytochemicals are highly inducible; therefore methods could be developed to enhance their production by the exogenous application of chemical inducers/elicitors. In the present experiment, chitosan was used as an elicitor molecule to improve the phytochemical content of spinach plant. When applied at a concentration of 0.01 mg/ml as a foliar spray, chitosan was able to cause an increase in the enzymatic (peroxidase, catalase and phenylalanine ammonium lyase (PAL)) and non enzymatic (total phenolics, flavonoids and proteins) defensive metabolites, as well as, in the total antioxidant activity of the spinach leaves. A 1.7-fold increase in the total phenolics, a 2-fold increase in total flavonoid and a 1.6-fold increase in total protein were achieved with the treatment. A higher level of enzymatic activity was observed with a 4-fold increase in peroxidase and approximately 3-fold increases in catalase and phenylalanine ammonium lyase activity. Antioxidant activity showed a positive correlation between phenolic compounds and the enzymatic activity. Direct analysis in real time mass spectrometry (DART-MS) was applied to generate the metabolite profile of control and treated leaves. DART analysis revealed the activation of phenylpropanoid pathway by chitosan molecule, targeting the synthesis of diverse classes of flavonoids and their glycosides. Important metabolites of stress response were also visible in the DART spectra, including proline and free sugars.