Biotechnological Perspective of Reactive Oxygen Species (ROS)-Mediated Stress Tolerance in Plants

All environmental cues lead to develop secondary stress conditions like osmotic and oxidative stress conditions that reduces average crop yields by more than 50% every year. The univalent reduction of molecular oxygen (O2) in metabolic reactions consequently produces superoxide anions (O2•−) and other reactive oxygen species (ROS) ubiquitously in all compartments of the cell that disturbs redox potential and causes threat to cellular organelles. The production of ROS further increases under stress conditions and especially in combination with high light intensity. Plants have evolved different strategies to minimize the accumulation of excess ROS like avoidance mechanisms such as physiological adaptation, efficient photosystems such as C4 or CAM metabolism and scavenging mechanisms through production of antioxidants and antioxidative enzymes. Ascorbate-glutathione pathway plays an important role in detoxifying excess ROS in plant cells, which includes superoxide dismutase (SOD) and ascorbate peroxidase (APX) in detoxifying O2•−radical and hydrogen peroxide (H2O2) respectively, monodehydroascorbate reductase (MDHAR), dehydroascorbate reductase (DHAR) and glutathione reductase (GR) involved in recycling of reduced substrates such as ascorbate and glutathione. Efficient ROS management is one of the strategies used by tolerant plants to survive and perform cellular activities under stress conditions. The present chapter describes different sites of ROS generation and and their consequences under abiotic stress conditions and also described the approaches to overcome oxidative stress through genomics and genetic engineering

An Open Label Pre and Post Test Clinical Evaluation of Efficacy of Tila Taila Abhyanga and Massage of Yoni in Cystocele with Special Reference to Chyuta Avastha of Vasti

Prolapse or downward displacement of pelvic organs especially vagina, uterus and rectum is a common and disabling condition among women of menopausal age group. It affects their quality of life also. Displacement of vaginal anterior compartment results in cystocele. Quoting Acharya Susruta reference, the aim of this study is to find the efficacy of Tila taila yoni Abhyaṅga in Cyuta avastha of Vasti with respect to first degree cystocele. 30 subjects were selected satisfying inclusion and exclusion criterias with the approval of Institutional ethical committee. Clinical evaluation is done with the help of relevant subjective and objective parameters. The subjective parameters were assessed before and after the treatment for a period of one month with UDI questionnaire and objective parameter with Baden-Walker system of grading Pelvic Organ Prolapse. Three months follow-up evaluation was also done with same parameters. The Wilcoxon Signed Rank Test is used to statically decompose the clinical data. Subjective parameters showed improvement of the condition viz frequency and urgency of urination, urine leakage with and without any activity, cough, sneeze, small amount of urine leakage, difficult and incomplete bladder emptying, bulging in vagina However, leakage not related to urgency, lower abdominal pressure, painful urination and lower abdomen or genital area, pelvic area heaviness or dullness, pelvic discomfort and burning micturition showed only a little reduction with the treatment. Objective parameter is also highly statistically significant at p value < 0.001

Membrane processing for purification and concentration of β-glycosidases from barley (Hordeum vulgare)

Tangential flow ultrafiltration with a polyethersulfone (100 kDa) membrane was used for the purification and concentration of β-glycosidases (β-galactosidase and β-glucosidase) from aqueous extract of barley. The performances of mode 1 (concentration followed by diafiltration) and mode 2 (diafiltration followed by concentration) were compared. In mode 1 activity recoveries of 91.44 and 88% as well as purifications of 1.84 and 1.77-fold for β-galactosidase and β-glucosidase, respectively, were obtained in a total processing time of about 9 h. In mode 2 activity recoveries of 95.68 and 91.76% with purifications of 4.56 and 4.38-fold for β-galactosidase and β-glucosidase, respectively, were obtained in a total processing time of about 6 h. The removal of total carbohydrates and protein was 56.74 and 50.73%, respectively, in mode 1, whereas it was 81.46 and 79.04%, respectively, in mode 2. The diafiltration volume and volume concentration of 3 were maintained in both mode 1 and 2. Flux decline was severe in mode 1 and led to a long processing time of about 9 h. These results indicate that mode 2 was better than mode 1 for purification of β-glycosidases

Differential partitioning of β-galactosidase and β-glucosidase using aqueous two phase extraction

Aqueous two phase extraction (ATPE) is used for the first time for simultaneous separation and purification of β-galactosidase and β-glucosidase from barley (Hordeum vulgare). The influence of various process parameters such as polymer molecular weight and its concentration, salt type and its concentration, system pH, tie line length, phase volume ratio and neutral salt addition on separation and purification of these two enzymes was evaluated. The β-galactosidase and β-glucosidase were selectively partitioned to top and bottom phases, respectively. Suitable conditions for purification were found in aqueous two phase system, having 14% (w/w) polyethylene glycol 1500/13% (w/w) ammonium sulphate, at tie line length of 19.65% (w/w). Single stage of ATPE resulted in an activity recovery of 98.26% with purification of 2.1 fold of β-galactosidase and an activity recovery of 92.58% with purification of 3.3 fold of β-glucosidase. Second stage of ATPE with respective new phases increased the purification of β-galactosidase and β-glucosidase to 2.4 and 4.1 fold, respectively. During ATPE, conditions which enabled a balance between yield and purification of both the enzymes were selected. Further ultrafiltration in diafiltration mode increased the purification of enzymes (β-galactosidase 6.8 fold and β-glucosidase 7.7 fold) besides the removal of the phase components

Convenient synthesis of chromones and quinolinones

A one pot synthesis of substituted chromones and quinolinones by condensing commercially available and cheaper molecules like salicylic acid and anthranilic acid respectively with alkenes/nitriles followed by insitu cyclization using ammonium acetate as base has been achieved

Mixed reverse micellar systems for extraction and purification of β-glucosidase

Mixed reverse micellar (MRM) systems of sodium bis(2-ethylhexyl)sulfosuccinate (AOT) and nonionic surfactants (Tween 20, Tween 80, Tween 85 and Triton X-100) in iso-octane were used for the extraction and primary purification of β-glucosidase (EC 3.2.1.21) from the aqueous extract of barley (Hordeum vulgare) for the first time. Studies are carried out with both phase transfer as well as injection mode of reverse micellar extraction, among which, injection mode is observed to be more suitable for β-glucosidase extraction. The process parameters such as concentration of surfactants and their molar ratio, type of solvent, volume of sample injected and its protein concentration, pH and ionic strength of the initial aqueous phase for forward extraction, buffer pH, concentration of hexanol and salt during back extraction are varied to maximize the extraction efficiency. The molar ratio of AOT:nonionic above 4.5:1.0 only resulted in clear phase formation and below this ratio precipitation was observed at the interface during forward extraction. Mixed reverse micelles found to solubilize almost three times more volume of water and protein than AOT alone under otherwise similar conditions. Activity recovery was found to be in the order of AOT/Tween 20 > AOT/Tween 80 > AOT/Triton X-100 > AOT/Tween 85 > AOT. MRM system of 150 mM AOT/15 mM Tween 20 has resulted in maximum activity recovery of 95.18% and degree of purification of 4.8-fold

Reverse micellar extraction of β-galactosidase from barley (Hordeum vulgare)

The reverse micellar system of sodium bis(2-ethylhexyl)sulfosuccinate (AOT)/isooctane was used for the extraction and primary purification of β-galactosidase (EC 3.2.1.23) from the aqueous extract of barley (Hordeum vulgare) for the first time. The process parameters such as the concentration of the surfactant, the volume of the sample injected, and its protein concentration, pH, and ionic strength of the initial aqueous phase for forward extraction, buffer pH, and salt concentration for back extraction are varied to optimize the extraction efficiency. Studies carried out with both phase transfer and injection mode of reverse micellar extraction confirmed the injection mode to be more suitable for β-galactosidase extraction. The extent of reverse micellar solubilization of proteins increased with an increase in protein concentration of the feed sample. However, back extraction efficiency remained almost constant (13–14.4%), which indicates the selectivity of AOT reverse micelles for a particular protein under given experimental conditions. β-Galactosidase was extracted with an activity recovery of 98.74% and a degree of purification of 7.2-fold

Separation and purification of bromelain by reverse micellar extraction coupled ultrafiltration and comparative studies with other methods

Reverse micellar extraction (RME) is a promising liquid-liquid extraction technique for downstream processing of biomolecules from dilute solutions. An integrated approach of coupling RME with ultrafiltration is attempted to improve the overall efficiency of extraction and purification of bromelain from aqueous extract of pineapple core. The performance of RME is compared with aqueous two-phase extraction (ATPE), another potential liquid-liquid extraction technique and conventional ammonium sulphate precipitation technique. The reverse micellar system of cationic surfactant cetyltrimethylammoniumbromide/isooctane/hexanol/butanol used for RME resulted in an activity recovery of 95.8% and purification of 5.9-fold. The purification of bromelain increased to 8.9-fold after ultrafiltration. Alteration of aqueous phase pH during RME facilitated the differential partitioning of bromelain and polyphenoloxidase. Comparison of RME results with ATPE (activity recovery of 93.1% and purification of 3.2-fold) and the conventional ammonium sulphate precipitation (activity recovery of 82.1% and purification of 2.5-fold) indicated the improved performance of RME