Establishment of callus cultures and quantification of Caffeic acid using HPTLC from Desmodium gangeticum (L.).

Desmodium gangeticum (L.) belonging to family Fabaceae is an economically important medicinal plant which isutilised in Dashmoolarishta. Various bioactive compounds have been isolated from whole plant and roots, and one of them is an important phenolic compound - caffeic acid (CA). This phenolic acid and its derivatives have antioxidant, anti-inflammatory, anticarcinogenic and hepatocarcinoma, a highly aggressive and causing considerable mortality across the world. In the present study, leaf explants were placed on MS medium fortified with different concentration of cytokinin (BA/Kn) and auxin (IAA/NAA) for establishing callus cultures. MS medium fortified with BA (20 µM) and IAA (2 µM) was optimised for the same. Methanolic extracts of in vivo leaf sample (DG1) and in vitro sample (leaf derived callus) (DG2) were assessed for CA quantification using HPTLC. Thus, the chemical fingerprint that was obtained, confirmed that DG 2 of D. gangeticum exhibited the potency to synthesise more amount of CA (316 ± 7.5 µg/g DW) in comparison to DG1 which was 194 ± 2.3 µg/g DW.

Sugar osmolyte inhibits and attenuates the fibrillogenesis in RNase A: An in vitro and in silico characterizations.

Mechanisms of protein aggregation are of immense interest in therapeutic biology and neurodegenerative medicine. Biochemical processes within the living cell occur in a highly crowded environment. The phenomenon of macromolecular crowding affects the diffusional and conformational dynamics of proteins and modulates their folding. Macromolecular crowding is reported to cause protein aggregation in some cases, so it is a cause of concern as it leads to a plethora of neurodegenerative disorders and systemic amyloidosis. To divulge the mechanism of aggregation, it is imperative to study aggregation in well-characterized model proteins in the presence of macromolecular crowder. One such protein is ribonuclease A (RNase A), which deciphers neurotoxic function in humans; therefore we decided to explore the amyloid fibrillogenesis of this thermodynamically stable protein. To elucidate the impact of crowder, dextran-70 and its monomer glucose on the aggregation profile of RNase-A various techniques such as Absorbance, Fluorescence, Fourier Transforms Infrared, Dynamic Light Scattering and circular Dichroism spectroscopies along with imaging techniques like Atomic Force Microscopy and Transmission Electron Microscopy were employed. Thermal aggregation and fibrillation were further promoted by dextran-70 while glucose counteracted the effect of the crowding agent in a concentration-dependent manner. This study shows that glucose provides stability to the protein and prevents fibrillation. Intending to combat aggregation, which is the hallmark of numerous late-onset neurological disorders and systemic amyloidosis, this investigation unveils that naturally occurring osmolytes or other co-solutes can be further exploited in novel drug design strategies.