Mrs. Sristy Shikha is pursuing her PhD under the guidance of Dr. Mani Shankar Bhattacharyya at Institute of Microbial technology (IMTECH), Chandigarh, India. After completing her M.Sc. in Marine Biotechnology from Annamalai University, She joined IMTECH for Ph.D. She qualified various prestigious national level fellowship exams such as JNU-DBT scholarship for M.Sc. (Rank 191), ICMR-JRF for Ph.D. (awarded only top 120 students) and CSIR-UGC-JRF (rank UGC-53). Her Ph.D. work is focused on synthesis of various types of nanoparticles, conjugation of drug/enzyme to enhanced activity as compared to their unconjugated counterpart and developing their applications. Part of her work has been published in Microbial Cell Factories and some are in communication. [email protected]
Sophorolipids (SL), a glycolipid class of microbial biosurfactants have been used for greener and environment compatible synthesis of gold nanoparticles (AuNPs) in this study. Various parameters like concentration of SL, pH and temperature were optimised for synthesis of nanoparticles. Initially, SL was used as reducing and capping agent for the synthesis of gold nanoparticles from chloroauric acid under different conditions. Since the synthesis procedure required several hours and polydispersity of these nanoparticles was very high, therefore protocol was modified by adding sodium borohydride as reducing agent to address issues. Characterizations of sophorolipid mediated gold nanoparticles (AuNPs-SL) were performed using UV- visible spectroscopy, Dynamic light Scattering (DLS), FTIR and transmission electron microscopy (TEM). Capping of SL onto the AuNPs was confirmed by FTIR and TEM micrograph. Further, AuNPs-SL was checked for antimicrobial activity against bacteria such as Gram negative Vibrio cholerae, Gram positive Staphylococcus aureus and fungi Candida albicans. The standard dilution method was used to determine the minimum inhibitory concentration (MIC) and viability was checked by XTT assay. AuNPs-SL was found to be effective against all these microbes as MICs. Earlier reports suggest that, SL either does not show activity or requires very high concentration against Gram negative bacteria. Contrary to this, we found AuNPs-SL was very potent in killing V. cholerae also. Thus, this study helps in greener ecofriendly synthesis of nanosized particles with potential antimicrobial properties for both Gram negative and Gram positive bacterium which are of great interest in the development of newer therapeutic drugs.
Martina Cebova has completed her PhD at the age of 24 from Commenius University in Slovakia and postdoctoral studies from Maine Medical Center Research Institute in USA. After, she has continued to work at the Institute of Normal and Pathological Physiology of Slovak Academy of Sciences as a junior scientist and since 2016 she is a scientific secretary of the Institute.She has published in reputed journals and has been serving as an editorial board member of repute.
The renin-angiotensin-aldosteron system is a cascade that governs cardiovascular, renal, and adrenal functions. Aliskiren is a direct renin inhibitor. We determined whether aliskiren has an effect on hypertension, NOS activity and eNOS expression in the heart and aorta. 12-week-old male SHRs were assigned to untreated group, group treated with powdered aliskiren (25mg/kg/day), group treated with nanoparticle-loaded aliskiren (25mg/kg/day) and group treated with nanoparticles only for 3 weeks by gavage. Blood pressure (BP) was measured by the tail-cuff plethysmography. NOS activity was determined by conversion of 3[H]Arginine to 3[H] Citrulline. BP in powdered aliskiren group was lower (178.7±1.8 mmHg) than in controls (203.4±4.3mmHg). In addition, in nanoparticle-loaded aliskiren group BP was decreased to 153.8±3.9 mmHg - the level lower in comparison to both, controls and powder aliskiren group. Moreover, both aliskiren groups reduced myocardial hypertrophy in comparison to untreated SHR. Only nanoparticle-loaded aliskiren increased the activity of NOS in the heart, despite decrease of eNOS in comparison to untreated SHR. On the other hand, nanoparticles only decrease both activity and eNOS expression in investigated tissues. In conclusion, despite the diminished effect of nanoparticles on the tissues, aliskiren realized gradually was able to increase NOS activity in the heart which could contribute to BP and hypertrophy decrease. Aliskiren may represent an effective, novel approach to the treatment of hypertension and related disorders. The encapsulation may protect drugs against degradation and thus increase their bioavailability in organs. However, more suitable and biocompatible polymeric nanoparticles are needed. Supported by VEGA 2/0170/17, 2/0195/15, APVV-14-0932.