Ganga Bisht

Chemical composition and analgesic activity of Senecio rufinervis essential oil.

Context: Senecio rufinervis D.C (Asteraceae) is a tall aromatic herb, commonly found in Uttarakhand, India. No investigations on the biological activity of this plant have been published so far. Hence, this plant species became a subject of our scientific interest. Objective: The aim of the study was to investigate the chemical composition and analgesic activity of Senecio rufinervis essential oil in mice using both thermal and chemical models of pain. Materials and methods: Essential oil from dried leaves of Senecio rufinervis was extracted by steam distillation and then subjected to GC-MS analysis. Varying doses of essential oil were given to mice, 30 min prior to the induction of abdominal constrictions and determination of mean reaction time in hot-plate maintained at 55° ± 0.5°C. Results: The main component detected in the essential oil of Senecio rufinervis was germacrene D (40.19%) followed by β-pinene (12.23%), β-caryophyllene (6.21%) and β-longipinene (4.15%). Essential oil exhibited significant and dose-dependent analgesic activity against acetic acid-induced writhing in mice. The percentage inhibition in number of writhes produced by 25, 50 and 75 mg/kg doses was, respectively, 69, 80 and 85%. The oil, at doses 50 and 75 mg/kg, significantly increased the mean latency in the hot-plate after 15 and 30 min of drug administration as compared to the control group. Discussion and conclusion: The results depicted both central and peripheral analgesic activity of S. rufinervis essential oil which was attributed to the presence of terpenes.

Recent Trends of Polymer-Protein Conjugate Application in Biocatalysis: A Review

Proteins, particularly enzymes, are often used in bioreactors to catalyze biosynthetic reactions. However, one of the major challenges in applying proteins in bioreactors is enzyme stability and recovery. This review is an enlightening discussion on recent trends and advancements used to alleviate these limitations completely or to minimize them. Two major strategies, polymer-based enzyme immobilization and polymeric enzyme nanoreactors have been discussed systematically. Further, this review puts light on various methods such as smart polymer-based supports which have been exploited for their ability to regulate ligand-protein interactions. In addition, chemical moieties like protein-based microcrystals, cross-linked enzyme aggregates, and polymer-based nanoreactors have also been discussed in a comprehensive way focusing more on their unique applicability and target-specific actions. Polymer-based nanoreactors are described in detail in vivo together with enhancement of the enzyme stability and controlled function based on the compartmentalization of enzymes. Among the two novel nanoreactor approaches, dendrimers have been exploited as multifunctional enzymatic carriers, while capsomes are designed to regulate poly-enzymatic reactions through intravesicular compartmentalization of a multitude of enzymatic reactions.