Venkata Subbaiah Kotakadi

Simple and rapid biosynthesis of stable silver nanoparticles using dried leaves of Catharanthus roseus. Linn. G. Donn and its anti microbial activity.

Nanoparticles have been used to alter and improve the pharmacokinetic and pharmacodynamic properties of various types of drug molecules. The plant extracts are eco-friendly, economical and cost effective for synthesis of large scale of nanoparticles. In this paper we represent the synthesis of silver nanoparticles (AgNPs) from room dried leaves of Vinca rosea. The AgNPs were characterized by UV-vis spectroscopy. The AgNPs are crystalline in nature, were determined from scanning electron microscopy (SEM) coupled with energy dispersive X-ray (EDX), X-ray diffraction patterns (XRD), and also the size of the NPs was calculated by using Hariba Nanoparticle analyzer and the stability was calculated by using the Zetapotential. The nanoparticles obtained from leaf extracts were of size 27±2 and 30±2 respectively and Zetapotential of AgNPs was found to be -63.1 mV, so it indicates the dispersion and stability. The synthesized AgNPs have very good antimicrobial activity.

Green synthesis and spectral characterization of silver nanoparticles from Lakshmi tulasi (Ocimum sanctum) leaf extract

A simple method for the green synthesis of silver nanoparticles (AgNPs) using aqueous extract of Lakshmi tulasi (Ocimum sanctum) leaf as a reducing and stabilizing agent. AgNPs were rapidly synthesized using aqueous extract of tulasi leaf with AgNO(3) solution within 15 min. The green synthesized AgNPs were characterized using physic-chemical techniques viz., UV-Vis, X-ray diffraction (XRD), scanning electron microscope (SEM) coupled with X-ray energy dispersive spectroscopy (EDX) and Fourier transform-infrared spectroscopy (FT-IR). Characterization data reveals that the particles were crystalline in nature and triangle shaped with an average size of 42 nm. The zeta potential of AgNPs were found to be -55.0 mV. This large negative zeta potential value indicates repulsion among AgNPs and their dispersion stability.

Anti-proliferative and Apoptotic Effects of Basella rubra (L.) Against 1, 2-Dimethyl Hydrazine-induced Colon Carcinogenesis in Rats

Colorectal cancer is a very prevalent diagnosed cancer. The current study was performed in order to examine the role of BRAE (Basella rubra aqueous extract) in regulating aberrant crypt foci (ACF) formation, cell proliferation and inhibition of apoptosis in a colon carcinogenesis model in male Wistar rats. Rats were randomly allocated into six groups. Group I served as control, and group II acted as a drug control administered BRAE (250mg/kg b.w.) orally for 30 weeks. Rats in group III-VI were given subcutaneous injections of DMH (25mg/kg b.w. weekly) for 15 weeks to initiate colon carcinogenesis. Those in group IV and VI were administered BRAE along with DMH injections. Rats in group V were administered with BRAE after cessation of DMH injection. After 30 weeks of experimental period colons were obtained from experimental groups and analyzed for ACF incidence, argyrophilic nucleolar organizing region- associated proteins (AgNOR) count, histopathological and immunohistochemical changes. Only in DMH exposed groups were ACF and AgNOR numbers increased. Administration of BRAE appreciably decreased the numbers of ACF and AgNOR in BRAE treated groups. Histopathological findings revealed a high level of dysplastic changes with decreased number of goblet cells found only in only DMH injected rats. Administration of BRAE in treated group rats reversed these changes. Expression markers for cell proliferation (PCNA and Ki67) were elevated in DMH treated rats, but reduced with BRAE treatement. This expression was reversed with apoptosis markers (p53 and Caspase-3). Thus the results results of the present study were found to be significant and confirmed the potential efficacy of BRAE against colon carcinogenesis.

Synthesis, Characterization, and Antibacterial Activity of New Linezolid-Based Phosphoramidate Derivatives

GRAPHICAL ABSTRACT Abstract A series of new linezolid-based phosphoramidate derivatives 5(a-j) were synthesized in high yields from a linezolid intermediate, [3-(3-fluoro-4-morpholinophenyl)-5-(hydroxymethyl) oxazolidin-2-one] to develop new antibacterial agents. The structures of the newly synthesized compounds were elucidated by mass, 1H, 13C & 31P NMR, IR and Elemental analysis spectral characterization data. All the synthesized compounds were screened for their antibacterial activity against recipient (Streptomycin resistant), donor (Rifampin resistant), and mutant (Streptomycin resistant) Gram –Ve E. coli strains using Amoxiclav as a standard.

Computer Aided Molecular modeling approach of H & E (Haemotoxylin & Eosin) images of Colon Cancer

Cancer detection and classification of histopathological images is the standard clinical practice for the diagnosis and prognosis of any cancer. In this paper we present the colon cancer detection and classification of benign and malignant tumor (Nuclei) based on H & E stained histopathology and color segmentation based staining method to distinguish the different types of tissues in biomedical application. Nucleus detection in H&E is a challenging problem considering the variability, heterogeneity, low contrast, K means clustering, and differing typologies of nuclei to distinguish different types of tissues. There are strong indications that morphological analysis in H&E can serve as a biomarker. The segmentation approach is completely colour based and uses k-means clustering technique. This technique uses a series of algorithm steps which is an image processing approach in distinguishing the different tissue types. These algorithm steps are modelled in image processing tool box of MATLAB v7. 0. Modelling steps involved are from reading the image to segmentation of the nuclei into a separate image. Further there are also the intermediate steps that are involved between reading the image and segment the nuclei into a separate image in MATLAB real-time simulation environment.

Nano-BF3.SiO2 Catalyst-Promoted Michaelis-Arbuzov Reaction: Solvent-Free Synthesis and Antimicrobial Evaluation

GRAPHICAL ABSTRACT Abstract A simple, convenient synthetic route for the synthesis of novel dialkyl heteroaryl phosphonates by a reusable and green nano-BF3.SiO2 solid catalyst under solvent-free conditions through Michaelis–Arbuzov reaction with high yields is presented. All the newly synthesized compounds were characterized by spectral data and screened for their antimicrobial activity. Some of the compounds exhibited potent antibacterial activity against all the tested pathogens, and warrant further investigation.

Synthesis of novel N-aryl-4-[6-(2-fluoropyridin-3-yl)quinazolin-2-yl]-piperazine-1-carboxamide or -carbothioamide derivatives and their antimicrobial activity

A series of novel N-aryl-4-[6-(2-fluoropyridin-3-yl)quinazolin-2-yl]-piperazine-1-carboxamide or -carbothioamide derivatives was synthesized by cyclization of 5-bromo-2-fluorobenzaldehyde and guanidine carbonate in the presence of dimethylacetamide followed by treatment with isoamylnitrite and diiodomethane in the presence of copper iodide to afford 6-bromo-2-iodoquinazoline. The latter was treated with piperazine in the presence of triethylamine followed by (2-fluoropyridin-3-yl)boronic acid in the presence of Pd(PPh3)2Cl2 to afford 6-(2-fluoropyridin-3-yl)-2-(piperazin-1-yl)quinazoline which was further treated with various substituted arylisocyanates and arylisothiocyanates to obtain the title compounds. The chemical structures of the synthesized compounds were confirmed by means of LC-MS, 1H, 13C NMR, IR, and mass spectra and elemental analysis. All the synthesized compounds were evaluated for their in vitro antibacterial activity against two Gram-positive and two Gram-negative bacterial species, as well as two different strains of antibiotic-resistant E. coli and for antifungal activity against two fungal strains. Some of the compounds have shown potential antimicrobial activity.