Bioactivity and nutritional quality of nutgall (Rhus semialata Murray), an underutilized fruit of Manipur.

Introduction: Underutilized fruits plays a significant role in socio economic, cultural, nutritional and ethnomedicinal status of tribal people. However, scientific studies on the nutritional and other pharmaceuticals/biological activities of these fruits are meagre. Hence, the present study dealt with the quantification of nutritional quality and deciphering the bioactivity of nutgall (Rhus semialata Murray syn. Rhus chinensis Mill.), an underutilized fruit crop mainly found in foothill tracks of Eastern Himalaya, India, China, Japan, Korea and other South East Asian countries. Methods: The Rhus semialata Murray fruits were collected from five different locations in Purul sub-division, Senapati district, Manipur, India. The nutritional composition of the fruit pulp was analysed. Further the fruit pulp was extracted in methanol and water. The methanol and water extracts were studied for bioactivity properties such as antioxidant, antihyperglycemic, antihypertensive, antihyperuricemia, anti-tyrosinase, and antimicrobial activity. Results and discussion: The fruit was rich in essential fatty acids. The presence of linoleic and oleic acids, along with traces of docosahexaenoic acid and eicosapantaenoic acid, revealed the potential food value of the fruit. 59.18% of the total amino acid composition of the protein present was constituted by essential amino acids. The IC50 value of methanolic extract (MExt) and Water extract (WExt) of the fruit were recorded as 4.05 ± 0.22 and 4.45 ± 0.16 µg/mL, respectively, in the DPPH assay and 5.43 ± 0.37 and 11.36 ± 2.9 µg/mL, respectively, in the ABTS assay as compared to Ascorbic acid (3 and 5.4 µg/mL in DPPH and ABTS assay, respectively). The CUPRAC assay also showed a high antioxidant potential of MExt and WExt (1143.84 ± 88.34 and 456.53 ± 30.02 mg Ascorbic Acid Equivalent/g, respectively). MExt and WExt of the fruit were more active against α-glucosidase (IC50 of 1.61 ± 0.34 and 7.74 ± 0.54 µg/ mL, respectively) than α-amylase enzyme (IC50 14.15 ± 0.57 and 123.33 ± 14.7 µg/mL, respectively). In addition, the methanolic fruit extract showed low to moderate pharmacological potential in terms of antihypertensive (Angiotensin converting enzyme-I inhibition), antihyperuricemia (xanthine oxidase inhibition), anti-tyrosinase, and antimicrobial activity. The IC50 values of angiotensin-converting enzyme I inhibition, xanthine oxidase inhibition and tyrosinase inhibition were recorded as 13.35 ± 1.21 mg/mL, 93.16 ± 4.65 mg/mL, and 862.7 ± 12.62 µg/mL, respectively. The study evidently indicates that nutgall fruit is a potential source of phytonutrients, bestowed with commercially exploitable, multifaceted health benefits.

DNA protection ability, antihyperglycemic potential and in-vivo toxicity assessment of arrowleaf tearthumb (Persicaria sagittata L.), a neglected aquatic plant species of Eastern Asia.

Persicaria sagittata L. (common name arrowleaf tearthumb, American) is an herbaceous edible plant with characteristics sessile leaves mainly found in wetland areas of North America and Eastern Asia. In Eastern Himalayan Region of India, the ethnic communities consumed this plant as vegetables. The present investigation suggests the plant is endowed with bioactive compounds having potential DNA protection ability and antihyperglycemic activity. The DNA nicking assay revealed that the methanolic extract of this plant has the potential to protect plasmid DNA against hydroxyl damage. The α-glucosidase and α-amylase inhibitory assay of this methanolic extract suggest more effectiveness in inhibition of α-amylase than the α-glucosidase. Further, proximate composition, micronutrient, total phenolic and flavonoid content of this underutilised aquatic plant was determined. And lastly the in-vivo cytotoxicity study of Persicaria sagittata L. plant extract suggest that the plant is less toxic to in-vivo system.

Growth kinetics, improved plant growth and alleviation of water stress in tomato by water stress tolerant bacteria.

Plants are subject to a variety of abiotic stresses contributed to yield losses of up to 50%, posing a significant challenge to global food production. To cope with drought stress, of 205 bacterial cultures investigated for moisture stress tolerant potential, 16 cultures showed promising results in improving the majority of plant growth ameliorating activities under water stress and non-stress conditions. Growth kinetics and plant growth ameliorating activities declined significantly with the increase in water stress level. Most of the isolates tolerant to water stress were Streptomyces and Pseudomonas species. Of these, four strains with the best results were selected for growing tomato under water stress conditions. The imposition of water stress severely inhibited the growth of tomato plants. However, bacterial strains alleviated the stress and enhanced plant growth performance. Antioxidant activity showed a promising result of protection from reactive oxygen species produced in plants because of water stress. Plants treated with bioinoculants also exhibited a substantial decline in lipid peroxidation. Water stress significantly reduced the yield of tomato. However, bioinoculants treated plants demonstrated significantly higher yields than untreated plants. Nutrient uptake and fruit quality also improved in the treated plants. Experiments point to the scope of developing a microbial formulation to alleviate water stress in higher plants.

Anticarcinogenic and Antioxidant Action of an Edible Aquatic Flora Jussiaea repens L. Using In Vitro Bioassays and In Vivo Zebrafish Model.

Oxidative stress is the major cause of many health conditions, and regular consumption of antioxidants helped to encounter and prevent such oxidative stress-related diseases. Due to safety concerns over long-term uses of synthetic antioxidants, natural antioxidants are more preferred. The purpose of this study is to investigate the antioxidant and anticancer activities of Jussiaea repens L., a wild edible flora found in Manipur, India. The antioxidant activity was evaluated using 1,1-diphenyl-2-picrylhydrazyl (DPPH), 2,2'-azino-bis (3-ethylbenzothiazoline-6-sulfonic acid) (ABTS), Ferric reducing antioxidant power (FRAP) assay and DNA-nicking assay. The anticancer activity was tested using five cancer lines viz., SKOV3 cells (ovarian), HeLa (cervical), MDA-MB-231 (breast), PANC-1 (pancreatic), and PC3 (prostate). The toxicity, developmental effect, antiproliferative activity was further tested using zebrafish embryos. The methanolic plant extract had higher polyphenol content than flavonoids. The in vitro study demonstrated a promising antioxidant capacity and DNA protection ability of this plant. The extract also showed cytotoxic activity against SKOV3, HeLa, MDA-MB-23, and PANC-1 cancer cell lines. The in vivo studies on zebrafish embryos demonstrated the extract's ability to suppress the developmental process and elicited more cytotoxicity to cancer cells than developing zebrafish embryos. Moreover, the in vivo studies on zebrafish embryos also indicated the antiproliferative activity of J. repens L. extract.

Comparative study on phenolic, flavonoids and in vitro antioxidant activity of wild edible plants from Loktak Lake wetland ecosystem under North East Indian Himalayan Region.

The present study investigates the antioxidant activity of 28 wild edible plants (WEPs) resources of Loktak Lake wetland ecosystem of Manipur, North East Indian Himalayan Region and their correlation with phenolics and flavonoids. Antioxidant activity was measured by DPPH, ABTS and FRAP assay. The antioxidant capacity was found to wide ranges of 1.71 to 263.7 µM TEAC/g fresh weight. In three assays, maximum antioxidant capacity is in same order Jussiaea repens L. > Gynura cusimbua (D. Don) Moore > Polygonum sagitattum L. ranging from 99.5 to 263.7 µM TEAC/g fresh weight. The correlation study established that all the three antioxidant assays are positively correlated and phenolics have contributed more in antioxidant activity than flavonoids. Among 28 WEPs, Jussiaea repens L. and Gynura cusimbua (D. Don) Moore were found to be most promising. These plants can be used as source of natural antioxidant additives, nutritional supplements or ingredients of functional foods.

Valorization of chicken feather waste into bioactive keratin hydrolysate by a newly purified keratinase from Bacillus sp. RCM-SSR-102.

The objective of this study is the characterization of a keratinase from Bacillus sp.RCM-SSR-102 and its application in the preparation of keratin hydrolysate from chicken feather waste. The purified KER102 keratinase was characterized as a serine-metallo protease having a molecular weight of 30 kDa with optimum pH and temperature of 10 and 50 °C respectively. The keratinase could retain 98% activity at pH 10 and above and 55% activity at 20% salt concentration. The KER102 keratinase was found to be stable in the presence of oxidizing agents, surfactants and organic solvents. The keratinase could also hydrolyze both soluble and insoluble complex protein substrates. The KER102 keratinase could hydrolyze up to 5% (w/v) feather releasing 1.7 ± 0.19 mg/mL soluble peptides. The feather keratin hydrolysate (FKH) had both antioxidant and antityrosinase activity. The IC50 value of FKH in 2, 2-diphenyl 1-picrylhydrazyl (DPPH) radical scavenging activity (1.02 ± 0.01 mg/mL), 2'-azino-bis-3-ethylbenzothiazoline-6-sulphonic acid (ABTS) radical scavenging activity (20 ± +00.04 µg/mL) and anti-tyrosinase activity (1.2 ± 0.22 mg/mL) was recorded. The FKH also had DNA protecting ability against oxidative damage. Antioxidant and anti-tyrosinase compounds have potential applications in the pharmaceutical and cosmeceutical industry. Hence, the purified keratinase can be a potential candidate for the production of antioxidant and antityrosinase compounds from chicken feather waste.

Feather degrading, phytostimulating, and biocontrol potential of native actinobacteria from North Eastern Indian Himalayan Region.

Twelve actinobacterial strains were isolated from tomato rhizospheric soil from Manipur, a state in North East Indian Himalayan Region and screened for keratinolytic and plant growth promoting traits. Nine promising isolates were identified as Streptomyces species using partial 16S rRNA gene sequencing. Among the seven isolates showing chicken feather degradation activity, three keratinolytic strains RCM-SSR-2, -6, and -12 were found to be the most efficient feather degrading strains achieving 90% feather weight loss within 48 h of incubation. They also showed maximum keratinase and soluble peptide production. Strain RCM-SSR-2, -5, -6, -8, and -11 showed positive results for all plant growth promoting traits tested. Maximum indole-3-acetic acid production was exhibited by RCM-SSR-6. Strain RCM-SSR-1, -2, -5, -6, -9, and -11 showed antagonistic activity against three important plant pathogens. Feather hydrolysate of RCM-SSR-6 was also evaluated for in vitro seed germination test using garden pea seeds. Higher concentration of feather protein hydrolysate (3 mg ml-1 ) inhibited shoot and root length of the germinating embryo. However, lower concentration (0.01 mg ml-1 ) of feather protein hydrolysate promoted seed germination. Among the 12 strains, four isolates namely RCM-SSR-1, -2, -5, and -6 were found to be promising as multi-traits plant growth promoting rhizobacteria for development of organic fertilizer, phytostimulator, and biocontrol agents.

Keratinolytic activities of alkaliphilic Bacillus sp. MBRL 575 from a novel habitat, limestone deposit site in Manipur, India.

Microbial degradation of keratinous wastes is preferred over physicochemical methods as the latter is costlier and not eco-friendly. Novel habitats are promising for discovery of new microbial strains. Towards discovery of novel keratinolytic bacteria, screening of bacterial strains from a novel limestone habitat in Hundung, Manipur, India was done and a promising isolate, MBRL 575, was found to degrade native chicken feather efficiently. It could grow over a broad pH range (Langeveld et al. in J Infect Dis 188:1782-1789, 2003; Park and Son in Microbiol Res 164:478-485, 2009; Zaghloul et al. in Biodegradation 22:111-128, 2011; Takami et al. in Biosci Biotechnol Biochem 56:1667-1669, 1992; Riffel et al. in J Biotechnol 128:693-703, 2007; Wang et al. in Bioresour Technol 99:5679-5686, 2008) and in presence of 0-15 % NaCl. Based on phenotypic characterization and 16S rRNA gene sequence analysis, the new keratinolytic limestone isolate was identified as Bacillus sp. MBRL 575. It produced 305 ± 12 U/ml keratinase and liberated 120 ± 5.5 mg of soluble peptides and 158 ± 4 mg of amino acids per gram of feather after 48 h of incubation at 30 °C in chicken feather medium. The strain could also degrade feathers of other species besides chicken. The cell-free enzyme was also able to degrade feather. Citrate and soybean meal were found to be the best carbon and nitrogen supplements for enhanced enzyme, soluble peptide and amino acid production. In addition to keratinolytic activity, MBRL 575 also exhibited antagonistic activity against two major rice fungal pathogens, Rhizoctonia oryzae-sativae (65 %) and Rhizoctonia solani (58 %).