Salicylic acid-mediated enhancement of resistance in tomato plants against Xanthomonas perforans.

Introduction: Bacterial spot disease of tomato was identified a few decades ago. The varying point of entry for the pathogen has enhanced the complexities for designing an effective disease management method. Recent advances in the use of inducers to elicit immune response in order to prepare the plant for a future attack by the pathogen are similar to the vaccination that is undertaken in humans and is a trending technology. Objectives: The present study aims at understanding the effect of salicylic acid (SA) for management of bacterial spot disease caused by Xanthomonas perforans. Methods: The study evaluated the effects of SA on the disease incidence along with seed germination and seedling vigor in two cultivars of tomato namely, Sun hybrid- resistant variety (R) and Quality- highly susceptible variety(HS). Results: The germination and seedling vigor, which was reduced in case of HS variety in comparison with that of the R variety, was notably improved after seed priming in both the cultivars. The antioxidant enzyme activities of ascorbate peroxidise (APx), catalase (CAT) and glutathione reductase (GR) were assessed which showed that the R variety reached maximum activity at 18 h post inoculation (hpi), 24 hpi and 21 hpi, respectively, whereas the HS variety reached maximum at 30 hpi for APx and 36 hpi for CAT and GR activities. The transcript accumulation using qRT-PCR was also evaluated showing mRNA accumulation was maximum in the R cultivar after SA priming at 1.5 mM concentration. Conclusion: the present study demonstrates the potential benefits of seed priming with SA to effectively elicit defence response in tomato seedlings against the bacterial spot disease.

Aflatoxins and food pathogens: impact of biologically active aflatoxins and their control strategies.

Globally disease outbreaks as a result of the consumption of contaminated food and feedstuffs are a regular primary problem. The foremost elements contributing to contamination are microorganisms, particularly fungi, which produce low-molecular weight secondary metabolites, with demonstrated toxic properties that are referred to as mycotoxins. Aflatoxins contaminate agricultural commodities and may cause sickness or fatality in humans and animals. Moreover, poor conditions of storage and a deficiency in regulatory measures in food quality control aggravate the main issue. For that reason, mycotoxin-related illness of nutrition represents a major health hazard for local populations. Government policies should make regulations aiming to avoid the entry of aflatoxins into food stuffs. For consumer safety, control and management strategies should be developed and implemented by regulatory authorities. There is the need for attention from farmers, scientists, government and collaborative minds throughout the country to ensure aflatoxin-free food. The present review is informative not only for health-conscious consumers, but also for relevant authorities with respect to paving the way for future research aiming to fill the existing gaps in our knowledge with regard to mycotoxins and food security. © 2016 Society of Chemical Industry.

Anti-inflammatory and antinociceptive effect of Pachygone ovata leaves.

CONTEXT: Pachygone ovata (Poir.) Miers ex Hook. F. et Thoms (Menispermaceae) is a rich source of bioactive bisbenzylisoquinoline and aporphine alkaloids. OBJECTIVE: This study investigates the in vitro and in vivo anti-inflammatory and antinociceptive potential of Pachygone ovata leaves. MATERIALS AND METHODS: Lipoxygenase (LOX) assay for anti-inflammatory activity was conducted using MeOH, EA, H and Aq extracts; followed by alkaloid isolation. The anti-inflammatory potential was determined using carrageenan-induced paw oedema and formalin tests for evaluation of Pachygone ovata analgesic effect. Different doses (100, 300 and 400 µg/kg) were administered orally to Wistar rats for a period of one week, once daily. RESULTS: MeOH and EA extract efficiently inhibited LOX (IC50 1.43 and 2.15 µg/mL, respectively). MeOH extract had better inhibiting capacity (57%) than indomethacin (51%) in carrageenan induced rats. MeOH extract (300 µg/kg) significantly reduced the increased levels of nitric oxide (8 ± 0.57 M), total leukocyte count (4.5 ± 0.05 cells 103/cells) and C-reactive protein (55 ± 0.45 mg/mL). There was a decrease in various serum biochemical markers (ALT, AST). Histopathological studies revealed reduction in oedema and decreased cellular infiltration on supplementation with MeOH extract. Furthermore, MeOH extract (300 µg/kg) and alkaloid fraction (400 µg/kg) effected both phases (neurogenic and inflammatory) of formalin injected models. DISCUSSION AND CONCLUSION: Inflammatory mediators play a key role in inflammation; therefore, keeping it in control is of utmost importance. The usefulness of Pachygone ovata leaves on pain and inflammation has been described, probably due to its effect on inflammatory mediators and high alkaloid content.

Assessment of membrane stabilizing activity from honey. An in-vitro approach.

BACKGROUND: esent study was conducted to evaluate Manoflora (MF), Polyflora (PF), Polyflora forest (PFf), and Processed (Pro) honey varieties to compare the in-vitro anti-inflammatory effects of aqueous honey samples in dose dependent manner. In-vitro anti-inflammatory activity was evaluated using membrane stabilization assay of RBCs at different aqueous honey concentrations. Material and method. The present investigation carried out for selected varieties of honey against erythrocytes exposed to both heat and hypotonic lyses and inhibition of membrane damage was compared to the standard drug acetylsalicylic acid. Results. Membrane damage was inhibited in both the model hemolysis of erythrocytes in vitro in a concentration dependent manner. Hypotonic solution inducing damage was inhibited by aqueous honey sample in ascending order ranged from 8.25% to 97.76% at 10 to 50 mg/ml and standard drug acetylsalicylic acid showing hemolysis protection 96.09% at 100 µg/ml concentration. In heat induced hemolysis model aqueous honey sample exhibited its protecting property during external stress condition in all samples ranged from 0.44% to 21.23% at 10 to 50 mg/ml and acetylsalicylic acid showed 39.38% at 100 µg/ml concentration. Among the variety PFf showed highest protecting nature for hypotonic solution induced lyses (97.76%) and heat induced hemolysis (21.23%) at 50 mg/ml respectively. Conclusion. With these investigations data conclude that the model exhibits marked anti-inflammatory effect. Future research is to be carried out to identify the molecules responsible in honey and its mechanism. METHODS: present study was conducted to evaluate Manoflora (MF), Polyflora (PF), Polyflora forest (PFf), and Processed (Pro) honey varieties to compare the in-vitro anti-inflammatory effects of aqueous honey samples in dose dependent manner. In-vitro anti-inflammatory activity was evaluated using membrane stabilization assay of RBCs at different aqueous honey concentrations. Material and method. The present investigation carried out for selected varieties of honey against erythrocytes exposed to both heat and hypotonic lyses and inhibition of membrane damage was compared to the standard drug acetylsalicylic acid. RESULTS: Membrane damage was inhibited in both the model hemolysis of erythrocytes in vitro in a concentration dependent manner. Hypotonic solution inducing damage was inhibited by aqueous honey sample in ascending order ranged from 8.25% to 97.76% at 10 to 50 mg/ml and standard drug acetylsalicylic acid showing hemolysis protection 96.09% at 100 µg/ml concentration. In heat induced hemolysis model aqueous honey sample exhibited its protecting property during external stress condition in all samples ranged from 0.44% to 21.23% at 10 to 50 mg/ml and acetylsalicylic acid showed 39.38% at 100 µg/ml concentration. Among the variety PFf showed highest protecting nature for hypotonic solution induced lyses (97.76%) and heat induced hemolysis (21.23%) at 50 mg/ml respectively. CONCLUSIONS: With these investigations data conclude that the model exhibits marked anti-inflammatory effect. Future research is to be carried out to identify the molecules responsible in honey and its mechanism involved.