Gitishree Das

Endophytes: A Treasure House of Bioactive Compounds of Medicinal Importance

Endophytes are an endosymbiotic group of microorganisms that colonize in plants and microbes that can be readily isolated from any microbial or plant growth medium. They act as reservoirs of novel bioactive secondary metabolites, such as alkaloids, phenolic acids, quinones, steroids, saponins, tannins, and terpenoids that serve as a potential candidate for antimicrobial, anti-insect, anticancer and many more properties. While plant sources are being extensively explored for new chemical entities for therapeutic purposes, endophytic microbes also constitute an important source for drug discovery. This review aims to comprehend the contribution and uses of endophytes as an impending source of drugs against various forms of diseases and other possible medicinal use.

Photo-mediated green synthesis of silver and zinc oxide nanoparticles using aqueous extracts of two mangrove plant species, Heritiera fomes and Sonneratia apetala and investigation of their biomedical applications.

Green synthesis by using biological agents has been a simple and effective approach for the synthesis of various forms of nanoparticles. The present investigation was intended to synthesis Ag-NPs and ZnO-NPs under photo-condition using the aqueous extracts of two mangrove plants namely Heritiera fomes and Sonneratia apetala and evaluate their potential biomedical applications. The formation of nanoparticles in aqueous solution of H. fomes and S. apetala under exposure to sun light was validated by change in color and formation of monodispersed NPs with a narrow particle size distribution. Fourier transform infrared spectroscopy (FT-IR) reveals the presence of Oxime and other heterocyclic compounds to be the most probable compounds responsible for the reduction and stability of nanoparticles in the solutions. The synthesized NPs displayed moderate free radical scavenging properties. The anti-inflammatory potential of ZnO-NPs was recorded to be comparatively higher than that of Ag-NP with 79% and 69.1% respectively. The Ag-NPs with unique properties of inhibiting α-amylase (91.14% and 89.16%) were found to be significantly high indicating its antidiabetic property. The synthesized NPs showed varied zone of inhibition (9-16mm) against the tested microbial pathogens. The synthesized nanoparticles possess strong biological activities in terms of antioxidant, anti-inflammatory, antidiabetic and antibacterial, potentials which could be utilized in various biological applications by the cosmetic, food and biomedical industries.

Kimchi and Other Widely Consumed Traditional Fermented Foods of Korea: A Review

Different types of fermented foods such as chongkukjang, doenjang, ganjang, gochujang, and kimchi are plentifully available and widely consumed in north eastern Asian countries including Korea. Among them, kimchi is one of the most popular Korean traditional food. It is prepared by fermenting the baechu cabbage together with other vegetables and lactic acid bacteria (LAB) with functional potential. Many types of ingredients are added to kimchi to enhance its taste, flavor, nutritional value, texture etc. A number of bacteria are involved in the fermentation of kimchi, but LAB are the dominant species in the fermentation process. The addition of other sub ingredients and formation of different by-products during fermentation eventually leads to eradication of putrefactive and pathogenic bacteria, and also increase the functionalities, nutritional and nutraceutical potential of kimchi. Kimchi possesses anti-inflammatory, antibacterial, antioxidant, anticancer, antiobesity, probiotic properties, cholesterol reduction, and antiaging properties. In the present review an attempt has been made to review the different types of fermented foods found in the Korean peninsula with detailed scientific research regarding preparation, processing, structure of the microecosystem, and health benefits of kimchi.

Revitalization of plant growth promoting rhizobacteria for sustainable development in agriculture

The progression of life in all forms is not only dependent on agricultural and food security but also on the soil characteristics. The dynamic nature of soil is a direct manifestation of soil microbes, bio-mineralization, and synergistic co-evolution with plants. With the increase in worlds population the demand for agriculture yield has increased tremendously and thereby leading to large scale production of chemical fertilizers. Since the use of fertilizers and pesticides in the agricultural fields have caused degradation of soil quality and fertility, thus the expansion of agricultural land with fertile soil is near impossible, hence researchers and scientists have sifted their attention for a safer and productive means of agricultural practices. Plant growth promoting rhizobacteria (PGPR) has been functioning as a co-evolution between plants and microbes showing antagonistic and synergistic interactions with microorganisms and the soil. Microbial revitalization using plant growth promoters had been achieved through direct and indirect approaches like bio-fertilization, invigorating root growth, rhizoremediation, disease resistance etc. Although, there are a wide variety of PGPR and its allies, their role and usages for sustainable agriculture remains controversial and restricted. There is also variability in the performance of PGPR that may be due to various environmental factors that might affect their growth and proliferation in the plants. These gaps and limitations can be addressed through use of modern approaches and techniques such as nano-encapsulation and micro-encapsulation along with exploring multidisciplinary research that combines applications in biotechnology, nanotechnology, agro biotechnology, chemical engineering and material science and bringing together different ecological and functional biological approaches to provide new formulations and opportunities with immense potential.

Chemical Composition and Antioxidant and Antibacterial Activities of an Essential Oil Extracted from an Edible Seaweed, Laminaria japonica L.

Laminaria japonica L. is among the most commonly consumed seaweeds in northeast Asia. In the present study, L. japonica essential oil (LJEO) was extracted by microwave-hydrodistillation and analyzed by gas chromatography and mass spectroscopy. LJEO contained 21 volatile compounds, comprising 99.76% of the total volume of the essential oil, primarily tetradeconoic acid (51.75%), hexadecanoic acid (16.57%), (9Z,12Z)-9,12-Octadecadienoic acid (12.09%), and (9Z)-hexadec-9-enoic acid (9.25%). Evaluation of the antibacterial potential against three foodborne pathogens, Bacillus cereus ATCC 10876, Escherichia coli O157:H7 ATCC 43890, and Staphylococcus aureus ATCC 49444, revealed that LJEO at a concentration of 25 mg/paper disc exerted high antibacterial activity against S. aureus (11.5 ± 0.58 mm inhibition zone) and B. cereus (10.5 ± 0.57 mm inhibition zone), but no inhibition of E. coli O157:H7. LJEO also displayed DPPH (1,1-diphenyl-2-picrylhydrazyl) free radical scavenging activity (80.45%), superoxide anion scavenging activity (54.03%), and ABTS (2,2′-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid) radical and hydroxyl radical scavenging at 500 µg/mL. Finally, LJEO showed high inhibition of lipid peroxidation with strong reducing power. In conclusion, LJEO from edible seaweed is an inexpensive but favorable resource with strong antibacterial capacity as well as free radical scavenging and antioxidant activity; therefore, it has the potential for use in the food, cosmetics, and pharmaceutical industries.

Dioscorea spp. (A Wild Edible Tuber): A Study on Its Ethnopharmacological Potential and Traditional Use by the Local People of Similipal Biosphere Reserve, India

A number of wild crops remain unexplored in this world and among them some have excellent medicinal and nutritional properties. India is a harbor of biodiversity in general and phytodiversity in particular. The plant diversity is distributed from the Western Ghats to Eastern Ghats, along with the North-Eastern region and from the Greater Himalayas to the plain of Ganga. Among these distributed floral regions of the country, the Eastern Ghats are important due to their rich floral diversity. The forests of Odisha form a major part of Eastern Ghats in general and the Similipal Biosphere Reserve (SBR) in particular. The SBR is inhabited by many local communities. The food and medicinal habits of these communities are not fully explored even today. They are dependent on the forests of SBR for their food and medicine. Among their collections from forests, root and tuberous plants play a significant role. The local communities of SBR use about 89 types of tuberous plants for various purposes. Dioscorea is one such tuber, having maximum use among the local of SBR. However, less documentation and no specific reports are available on the food and medicinal values of the species available in this part of the World. Dioscorea species, popularly known as Yam worldwide and as Ban Aalu in Odisha, India, is a prime staple medicinal-food substitute for the majority of rural and local people of the state of India. Of the 13 Dioscorea species available in SBR, 10 species are known to be bitter in taste and unpalatable when taken raw. Since less documentation is available on the Dioscorea species of SBR and their traditional uses, the present study was focused on the ethnobotany, nutritional and pharmacological values of these species along its nutraceutical importance.

Benefaction of probiotics for human health: A review

Humans are a unique reservoir of heterogeneous and vivacious group of microbes, which together forms the human-microbiome superorganism. Human gut serves as a home to over 100-1000 microbial species, which primarily modulate the host internal environment and thereby, play a major role in host health. This spectacular symbiotic relationship has attracted extensive research in this field. More specifically, these organisms play key roles in defense function, eupepsia along with catabolism and anabolism, and impact brain-gut responses. The emergence of microbiota with resistance and tolerance to existing conventional drugs and antibiotics has decreased the drug efficacies. Furthermore, the modern biotechnology mediated nano-encapsulated multiplex supplements appear to be high cost and inconvenient. Henceforth, a simple, low-cost, receptive and intrinsic approach to achieve health benefits is vital in the present era. Supplementation with probiotics, prebiotics, and synbiotics has shown promising results against various enteric pathogens due to their unique ability to compete with pathogenic microbiota for adhesion sites, to alienate pathogens or to stimulate, modulate and regulate the hosts immune response by initiating the activation of specific genes in and outside the host intestinal tract. Probiotics have also been shown to regulate fat storage and stimulate intestinal angiogenesis. Hence, this study aims to underline the possible beneficial impact of probiotics for human health and medical sectors and for better lifestyle.

Insight into MAS: A Molecular Tool for Development of Stress Resistant and Quality of Rice through Gene Stacking

Rice yield is subjected to severe losses due to adverse effect of a number of stress factors. The most effective method of controlling reduced crop production is utilization of host resistance. Recent technological advances have led to the improvement of DNA based molecular markers closely linked to genes or QTLs in rice chromosome that bestow tolerance to various types of abiotic stresses and resistance to biotic stress factors. Transfer of several genes with potential characteristics into a single genotype is possible through the process of marker assisted selection (MAS), which can quicken the advancement of tolerant/resistant cultivars in the lowest number of generations with the utmost precision through the process of gene pyramiding. Overall, this review presented various types of molecular tools including MAS that can be reasonable and environmental friendly approach for the improvement of abiotic and biotic stress resistant rice with enhanced quality.

TOWARDS A GREENER ENVIRONMENT: SYNTHESIS AND APPLICATIONS OF GREEN NANOPARTICLES

Rapid industrialization and urbanization is continuously damaging our environment with large amounts of hazardous and unwanted chemicals, gases or other substances that are released around the world. The development of nanoparticles has led to a revolution in the field of industrialization and modern diagnostic technology. However, the use of nanoparticles in the biomedical and diagnostic field has been restricted owing to the toxicity and harmful effects of metallic nanoparticles synthesized using physical and chemical methodology. This gave an opportunity to search for an ecofriendly and environmentally benign synthesis process for the nanoparticles, from the living system and thus the concept of green nanotechnology came into the limelight. Most of the physical and chemical methods used for the synthesis of nanoparticles are too expensive, time consuming and involve the use of toxic, hazardous chemicals that are responsible for various biological risks. Numerous efforts are being made throughout the world to develop ecofriendly technologies to produce environmentally benign, non-toxic products using green nanotechnology involving biotechnological tools (Joerger et al., 2000; Chauhan et al., 2012). Nanoparticles synthesized using biological methods have diverse characteristics, with greater stability and appropriate dimensions since they are synthesized using a one-step procedure, which results in elimination of various undesirable processing conditions (Ingale and Chaudhari, 2013). Detailed information regarding environment friendly methods for nanoparticle synthesis may facilitate development of more ecofriendly and benign nanoparticles, which will have the potential for use in various biomedical and health related applications. Therefore, the present review highlights the classification of nanoparticles, different sources of green synthesis, possible mechanisms of their synthesis and various applications.

Diversity of traditional and fermented foods of the Seven Sister states of India and their nutritional and nutraceutical potential: a review

ABSTRACT The Seven Sister states of northeast India are characterized by diverse population with different ethnic backgrounds. Indigenous and fermented foods are an intrinsic part of diet of these ethnic tribes. It is the oldest and most economical methods for development of a diversity of aromas, flavors, and textures as well as for food preservation and biological enrichment by manipulation of different microbial populations. Wild fruits and vegetables have more nutritional value than cultivated fruits and contribute to sustainable food production and security. Fermented products are region-specific and have their own unique substrates and preparation methods. Soybeans, bamboo shoots, and locally available vegetables are commonly fermented by most tribes. Fermented alcoholic beverages prepared in this region are unique and bear deep attachment with socio-cultural lives of local people. These products serve as a source of income to many rural people, who prepare them at home and market them locally. Detailed studies on nutritive and medicinal value of these products can provide valuable information and would prove beneficial in guiding the use of these products on a wider scale. Furthermore, the ethnobotanical field exploration, conservation of indigenous knowledge, and proper documentation of wild edible bio-resources are suggested for sustaining the livelihood of local communities.