Twenty-five strains of plant-growth-promoting rhizobacteria (PGPR) containing 1-aminocyclopropane-1-carboxylate (ACC) deaminase and 10 strains of rhizobia were isolated from rhizosphere soil samples and nodules of mung bean. They were screened in separate trials under salt-stressed axenic conditions. The three most effective strains of PGPR (Mk1, Pseudomonas syringae ; Mk20, Pseudomonas fluorescens ; and Mk25, Pseudomonas fluorescens biotype G) and Rhizobium phaseoli strains M1, M6, and M9 were evaluated in coinoculation for their growth-promoting activity at three salinity levels (original, 4 dS·m(-1), and 6 dS·m(-1)) under axenic conditions. The results showed that salinity stress significantly reduced plant growth but inoculation with PGPR containing ACC deaminase and rhizobia enhanced plant growth, thus reducing the inhibitory effect of salinity. However, their combined application was more effective under saline conditions, and the combination Mk20 × M6 was the most efficient for improving seedling growth and nodulation. The effect of high ethylene concentrations on plant growth and the performance of these strains for reducing the negative impact of saline stress was also evaluated by conducting a classical triple-response bioassay. The intensity of the classical triple response decreased owing to inoculation with these strains, with the root and shoot lengths of inoculated mung bean seedlings increasing and stem diameter decreasing, which is a typical response to the dilution in a classical triple response bioassay. Thus, coinoculation with PGPR containing ACC deaminase and Rhizobium spp. could be a useful approach for inducing salt tolerance and thus improving growth and nodulation in mung bean under salt-affected conditions.

This study was carried out to compare the antioxidant and nutritional properties of coconut (Cocos nucifera L.) sap with other natural sources of sugar such as sugar palm (Borassus flabellifer) and sugarcane (Saccharum officinarum L.). Coconut sap and juice from sugar palm and sugarcane were analyzed for proximate composition, pH and total soluble solid (TSS), color, sugar profile, vitamin profile, antioxidant properties (total phenolic contents, DPPH, FRAP, and ABTS), and mineral content. The results indicated that coconut sap possesses high DPPH (23.42%), FRAP (2.09 mM/ml), and ABTS (21.85%) compared with the juices. Coconut sap also had high vitamin C (116.19 µg/ml) and ash (0.27%) contents, especially in potassium (960.87 mg/L) and sodium (183.21 mg/L) which also indicating high content of minerals. These properties showed that coconut sap could be served as a potential healthier sugar source compared with sugar palm and sugarcane juices.

Enzyme assisted solvent extraction (EASE) of phenolic compounds from watermelon (C. lanatus) rind (WMR) was optimized using Response Surface Methodology (RSM) with Rotatable Central Composite Design (RCCD). Four variables each at five levels i.e. enzyme concentration (EC) 0.5-6.5 %, pH 6-9, temperature (T) 25-75 °C and treatment time (t) 30-90 min, were augmented to get optimal yield of polyphenols with maximum retained antioxidant potential. The polyphenol extracts obtained under optimum conditions were evaluated for their in-vitro antioxidant activities and characterized for individual phenolic profile by RP-HPLC-DAD. The results obtained indicated that optimized EASE enhanced the liberation of antioxidant phenolics up to 3 folds on fresh weight basis (FW) as compared to conventional solvent extraction (CSE), with substantial level of total phenolics (173.70 mg GAE/g FW), TEAC 279.96 mg TE/g FW and DPPH radical scavenging ability (IC50) 112.27 mg/mL. Chlorogenic acid (115.60-1611.04), Vanillic acid (26.13-2317.01) and Sinapic acid (113.01-241.12 μg/g) were major phenolic acid found in EASEx of WMR. Overall, it was concluded that EASE might be efficient and green technique to revalorize under-utilized WMR into potent antioxidant phenolic for their further application in food and nutraceutical industries.

In the current study, antioxidant potential of licorice extracts was determined through different assays. For optimum recovery of bioactive components, three solvents (ethanol, methanol, and ethyl acetate) were employed at different ratios with water (25:75, 50:50, and 75:25) and supercritical fluid extracts (SFE) were obtained at varying pressures (3,500, 4,500, and 5,500 psi).Results exhibited that the extraction of antioxidant compounds from licorice increased with increasing solvent concentration. Among solvent extracts, 75% ethanolic extract showed highest total phenolic content (TPC), total flavonoids content (TF), and antioxidant activity. The supercritical CO 2 extract obtained at 5,500 psi pressure exhibited highest values for TPC, TF, and antioxidant capacity. It was evident from HPLC analysis that the highest recovery of major bioactive components (glycyrrhizin and glabridin) was obtained through supercritical CO 2 extraction at elevated pressures. Practical applicationsLicorice is a rich source of biologically active components with history of medicinal use. The current study provides an approach to maximize the recovery of desired components from licorice that can be used in different formulations with antioxidant potential. K E Y W O R D S antioxidant activity, licorice, phytochemical content, solvent extraction, supercritical CO 2 extraction

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Background: Coconut sugar has a caramel color with a taste like brown sugar. It is commonly used as natural sweetener. However, coconut sugar has been produced from coconut sap using a traditional method that involves heating the sap at high temperature (>100 °C) in an open pan for a long period (3-5 h). This conventional method results in an over-cooked sugar, which leads to quality deterioration in terms of both its physical and chemical properties. The current study aimed to investigate the processing of coconut sap into sugar syrup using alternative processing techniques such as rotary vacuum evaporation (RE) and microwave evaporation (ME), comparing them with open-heat evaporation (OHE) technique. Results: Coconut sugar syrup produced by rotary evaporation at 60 °C and 250 mbar vacuum (RE-60) required the shortest production time (12.2 min) and the lowest processing temperature (54.8 °C) when compared with ME (13 min and 103.2 °C) and OHE (46.8 min and 101.6 °C). It also had a light brownish color with a higher L* value (35.17) than the ME (29.84) and OHE (23.84) methods.It was found to contain higher amounts of monosaccharides (fructose and glucose) and lower amounts of disaccharides (sucrose). Furthermore, the amount of energy required for RE-60 (0.35 kWh) was much less than for OHE (0.83 kWh). Conclusion: This study provided an alternative processing method for the sugar processing industry to produce coconut sugar using the rotary evaporation method at 60 °C under 250 mbar vacuum with better physicochemical qualities, shorter processing time, and minimum input energy.

Coconut (Cocos nucifera L.) sugar is a more nutritious alternative sugar source as compared to sugar palm (Borassus flabellifer) and sugarcane (Saccharum officinarum L.). This work was aimed to investigate the browning index (BI), vitamin profile and antioxidant properties of coconut sap sugar syrups, which were produced by different processing methods: rotary evaporation (RE), microwave evaporation (ME) and open-heat evaporation (OHE). The results obtained showed that coconut sugar syrup produced by RE-60 contained high antioxidant activities [DPPH (36.71%) and ABTS (34.84%), TPC (299.87 mg per 100 g sample) and FRAP (3.74 mm)]. These values were slightly lower than those of ME and OHE. Coconut sugar syrup (RE-60) also contained higher amounts of vitamin C (1587.27 mg L−1), vitamin B1 (97.44 mg L−1) and vitamin B3 (19.84 mg L−1) compared with those of ME and OHE coconut sugar syrups. RE-60 was the best method to produce coconut sugar syrup in a shorter time with lower browning index and higher vitamin contents.

Streptokinase (SK) is an enzyme that is used for the treatment of cardiovascular diseases. The current study focused on the enhanced production of SK by inducing mutation in Streptococcus agalactiae EBL-20 and optimization of medium components and culture conditions for the maximum growth of mutant derived strain. S. agalactiae EBL-32 was selected as a potent mutant after exposure of S. agalactiae EBL-20 to EMS for 180 minutes. SK activity obtained from mutant derived strain was found to be 1.6 fold higher as compared to the activity achieved by wild strain. Nutritional requirements of the mutated strain were optimized by single factor analysis method suggesting glucose as the optimum carbon source; yeast extract and peptone as a suitable nitrogen sources and corn steep liquor (CSL) as an appropriate substrate for the maximum SK production. The culture conditions determined by response surface methodology (RSM) suggested that a temperature value of 37.5⁰C and pH 7 of the fermentation medium with 2.50 mL inoculum size for 36 hours of incubation was optimum for maximum yield of SK. Hence the optimization studies resulted HIGHLIGHTS  Streptokinase isolated from Streptococcus agalactiae is an active thrombolytic agent  Ethyl methanesulfonate is an effective mutagenic agent for Streptococcus spp.  Response surface methodology resulted in 1.92-fold increased streptokinase activity Arshad, A.; et al. Brazilian Archives of Biology and Technology. Vol.62: e19170813, 2019-www.scielo.br/babt into 1.92 fold increase in the yield of SK suggesting the new isolate suitable for commercial scale production of SK.