Raja Sudhakaran

Bio: Raja Sudhakaran is an academic researcher from VIT University. The author has contributed to research in topics: Shrimp & White spot syndrome. The author has an hindex of 14, co-authored 42 publications receiving 545 citations. Previous affiliations of Raja Sudhakaran include University of Miyazaki.

Antibacterial and antibiofilm assessment of Momordica charantia fruit extract coated silver nanoparticle

Abstract: Silver nanoparticles were synthesized using the fruit extracts of Momordica charantia ( Mc -AgNPs). The structural characterization of Mc -AgNPs was performed by UV–vis spectroscopy, X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR) and Transmission electron microscopy (TEM). UV–vis recorded the absorbance spectra at 460 nm. XRD shows the crystalline nature of silver nanoparticles with various Bragg's reflection peaks at 111, 200, 220 and 311. FTIR spectra of the synthesized Mc -AgNPs showed strong bands at 1382, 1203, 1151, 1102, 1013 and 654 cm −1 which corresponds to O–H, C–H, C–C, C–OH and C–N groups. TEM showed the spherical shape of Mc -AgNPs with particle size between 16 nm. The antibacterial activity of Mc -AgNPs was tested against Gram-positive and Gram-negative bacteria. Mc -AgNPs showed greater inhibition of Enterococcus faecalis at 100 µg ml −1 compared to Aeromonas hydrophila . The biofilm inhibition of Mc -AgNPs was also higher against E. faecalis compared to A. hydrophila .

Real-time quantitative loop-mediated isothermal amplification as a simple method for detecting white spot syndrome virus.

Abstract: Aims White spot syndrome virus (WSSV) continues to be the most pathogenic virus among the crustacean aquaculture causing mass mortality. In the present study, we established a one-step, single tube, real-time accelerated loop-mediated isothermal amplification (real-time LAMP) for quantitative detection of WSSV. Materials and methods A set of six specially designed primers that recognize eight distinct sequences of the target. The whole process can be completed in 1 h under isothermal conditions at 63 degrees C. Detection and quantification can be achieved by real-time monitoring in an inexpensive turbidimeter based on threshold time required for turbidity in the LAMP reaction. A standard curve was constructed by plotting viral titre against the threshold time (T(t)) using plasmid standards with high correlation coefficient (R(2) = 0.988). Conclusions Sensitivity analysis using 10-fold dilutions (equivalent to 35 ng microl(-1) to 35 ag microl(-1)) of plasmid standards revealed this method is capable of detecting upto 100 copies of template DNA. Cross-reactivity analysis with DNA/cDNA of IHHNV, TSV, YHV-infected and healthy shrimp showed this method is highly specific for quantitative detection of WSSV. Significance and impact of the study WSSV real-time LAMP assay appears to be precise, accurate and a valuable tool for the detection and quantification of WSSV in large field samples and epidemiological studies.

Green Synthesis of Metallic Nanoparticles and Their Prospective Biotechnological Applications: an Overview

Abstract: The green synthesis of nanoparticles (NPs) using living cells is a promising and novelty tool in bionanotechnology. Chemical and physical methods are used to synthesize NPs; however, biological methods are preferred due to its eco-friendly, clean, safe, cost-effective, easy, and effective sources for high productivity and purity. High pressure or temperature is not required for the green synthesis of NPs, and the use of toxic and hazardous substances and the addition of external reducing, stabilizing, or capping agents are avoided. Intra- or extracellular biosynthesis of NPs can be achieved by numerous biological entities including bacteria, fungi, yeast, algae, actinomycetes, and plant extracts. Recently, numerous methods are used to increase the productivity of nanoparticles with variable size, shape, and stability. The different mechanical, optical, magnetic, and chemical properties of NPs have been related to their shape, size, surface charge, and surface area. Detection and characterization of biosynthesized NPs are conducted using different techniques such as UV-vis spectroscopy, FT-IR, TEM, SEM, AFM, DLS, XRD, zeta potential analyses, etc. NPs synthesized by the green approach can be incorporated into different biotechnological fields as antimicrobial, antitumor, and antioxidant agents; as a control for phytopathogens; and as bioremediative factors, and they are also used in the food and textile industries, in smart agriculture, and in wastewater treatment. This review will address biological entities that can be used for the green synthesis of NPs and their prospects for biotechnological applications.

Current Research Status of Fish Immunostimulants

Abstract: Abstrcat Immunostimulants are valuable for the prevention and control of fish diseases in aquaculture.Several immunostimulants such as polysaccharide and micronutritional factors and their effective mechanism are reviewed, meantime, existing problems in immunostimulant application and future research tendency are described.

Antibacterial Derivatives of Marine Algae: An Overview of Pharmacological Mechanisms and Applications

Abstract: The marine environment is home to a taxonomically diverse ecosystem. Organisms such as algae, molluscs, sponges, corals, and tunicates have evolved to survive the high concentrations of infectious and surface-fouling bacteria that are indigenous to ocean waters. Both macroalgae (seaweeds) and microalgae (diatoms) contain pharmacologically active compounds such as phlorotannins, fatty acids, polysaccharides, peptides, and terpenes which combat bacterial invasion. The resistance of pathogenic bacteria to existing antibiotics has become a global epidemic. Marine algae derivatives have shown promise as candidates in novel, antibacterial drug discovery. The efficacy of these compounds, their mechanism of action, applications as antibiotics, disinfectants, and inhibitors of foodborne pathogenic and spoilage bacteria are reviewed in this article.