Physiological and Biochemical Changes under Salinity and Drought Stress in Ricebean [Vigna umbellata (Thunb.) Ohwi and Ohashi] Seedlings

Aims: To study the effect of iso-osmotic potentials of drought and salinity during seedling growth stage in ricebean. Study Design: Completely randomised design. Place and Duration of Study: The lab experiment was conducted during the year of 2017- 2018 and 2018-2019 in ricebean variety Bidhan 1 at Department of Plant Physiology, Bidhan Chandra Krishi Viswavidyalaya, Kalyani, Nadia, West Bengal, India. Methodology: For studying the effect of iso-osmotic potential of salinity and drought stress, the solutions of NaCl and PEG 6000 with -0.2, -0.4 and -0.8 MPa osmotic potential were used and the experiment was conducted in sand culture using modified Hoagland solution [1] under laboratory condition of diffused light, at around 80±1% relative humidity (R.H.) and at a temperature of 28±1°C. Results: All the biochemical parameters under study, in general were adversely affected by the both stress with the effects being more drastic as the intensity of stress increased. The highest intensity of salinity stress was found to produce more adverse effects than drought in respect of RLWC, leaf chlorophyll as well as protein content in leaves of ricebean in the present experiment. While the content of soluble sugar, starch and phenol in the leaf were more drastically affected by drought stress. Conclusion: The drought stress was found to register more drastic effects on seedling growth as compared to iso-osmotic potential of salinity stress, especially, at the highest intensity of stress in ricebean cultivar Bidhan 1.

Cytokine response to dietary rehabilitation with curd (Indian dahi) & leaf protein concentrate in malnourished children.

Background & objectives: Protein energy malnutrition (PEM), an important cause of secondary immune deficiency, is associated with several abnormalities in the immune system including cytokine production. In the present study cytokine levels (both pro- and anti-inflammatory) were evaluated in protein energy malnourished children following nutritional rehabilitation with curd (Indian dahi) and leaf protein concentrate (LPC). Methods: Eighty moderately and severely malnourished children, 1-5 yr of age, received the WHO recommended diet for severe malnutrition, modified according to local dietary habits, containing in addition either curd or micronutrient-rich leaf protein concentrate, for a period of 15 days. Cytokine levels [tumour necrosis factor α (TNFα), interferon γ (IFNγ), interleukin-10 (IL-10), interleukin-4 (IL-4)] were measured before and after dietary rehabilitation. Results: The baseline cytokine levels (TNFα, IFNγ, IL-10 and IL-4) were high in malnourished children. Both the diets caused an increase in serum pro-inflammatory (TNFα, IFNγ), and anti-inflammatory (IL-10) cytokine levels after nutritional rehabilitation. The increase in IL-10 was significant in children receiving curd. There was an insignificant fall in IL-4 levels with both the diets. The cytokine response was comparable in children with moderate and severe malnutrition, as also in children < 2 yr to those between 2-5 yr. Interpretation & conclusions: The study suggests that cytokines (TNFα, IFNγ, IL-10 and IL-4) may serve as biological markers to assess the effect of functional foods like curd or LPC on immunity in malnutrition. Curd may help to maintain the balance in cytokine production by increasing the production of IL-10, and may be considered in place of milk in the nutritional rehabilitation of malnourished children.

Selection and Optimization of 2-DE System for Leaf Proteome Profiling of Different Ecotypes of Reed Growing in Natural Habitats / 生物化学与生物物理进展

An optimized two-dimensional polyacrylamide gel electrophoresis (2-DE) system for analyzing plant proteins was developed by evaluating different reagents and concentrations used in the sample extraction solutions and lysis buffers. Two main sample preparation methods, referred to as trichloroacetic acid (TCA)-acetone method and phenol extraction-ammonium acetate/methanol (phenol-NH4Ac/methanol) precipitation method, were compared. Four ecotypes of reed plants (Phragmites communis Trin.) from the desert region of north-western China were used as experimental materials: (1) swamp reed (SR) which grows in water about 1 m deep; (2) dune reed (DR) which grows on 5～10 m high sand dunes; (3) heavy salt meadow reed (HSMR) which grows on low-lying salt flats; and (4) light salt meadow reed (LSMR) which grows in the transition area between DR and HSMR growing areas. The optimized phenol-NH4Ac/methanol precipitation method consisted of extracting leaf proteins of different ecotypes of reed with water-saturated phenol and then precipitating with a 5-fold volume of 0.1 mol/L NH4Ac in methanol, followed by dissolving in the lysis buffer. The optimized protein lysis buffer consisted of 7 mol/L urea, 2 mol/L thiourea, 4% CHAPS, 2% Ampholine(pH 3.5～10∶pH 5～8 = 1∶4) and 65 mmol/L DTT. The prepared protein sample (80 ?g) was then separated by 2-DE gel and detected by silver staining method. This improved 2-DE system resulted in a 2-D protein profile of higher resolution and higher protein yields as analyzed by PDQuest software. Good results were also obtained when this 2-DE system was used in 2-D analysis of proteins from other plant materials, such as rice leaves, indicating that it is a suitable 2-DE system for analyzing leaf proteins of different plant species.