Poloxamer and Chitosan-Based In Situ Gels Loaded with Orthosiphon stamineus Benth. Extracts Containing Rosmarinic Acid for the Treatment of Ocular Infections.

Objectives: Orthosiphon stamineus Benth. (OS) is a commonly used medicinal plant for curbing bacterial infections globally. This work aimed to fabricate poloxamer and chitosan-based in situ gels loaded with standardized aqueous-ethanolic OS leaf extracts and investigate their antimicrobial efficacy as a potential remedy against ocular infections. Materials and Methods: In situ gels containing 0.5% w/v OS extract prepared using cold dispersion method were subjected to physicochemical characterization, including in vitro-release studies. Antimicrobial efficacy was tested against Staphylococcus aureus, Micrococcus luteus, Escherichia coli, and Pseudomonas aeruginosa using agar diffusion method. Results: Thin layer chromatography and high performance liquid chromatography chromatograms confirmed the presence of rosmarinic acid (RA) and sinensitin in OS extracts with same retention factor (0.26 and 0.49) and retention times (12.2 and 20.7 min) against reference standards. A homogenous brown coloured in situ gel exhibited low viscosity as a solution and increased viscosity in gel form at ocular temperature. The optimized formulations, P7 (21% P407/4% P188), P8 (21% P407/5% P188) and F5 (1.5% chitosan and 45% ß-glycerophosphate) exhibited ideal ocular pH (7.27-7.46), phase transition at ocular temperature (33-37°C) and prolonged RA release up to 12 h. Formulation F5 showed an inhibition zone of 4.3 mm against M. luteus. Conclusion: Among all, formulation F5 alone exhibited modest antimicrobial activity against M. luteus. OS extracts at 5% and 10% were most active against tested bacteria however, loading them into in situ gels resulted in sedimentation. Hence, isolation of RA from OS extract is suggested before loading into formulations for a better antimicrobial activity.

Molecular and Immunological Mechanisms Underlying the Various Pharmacological Properties of the Potent Bioflavonoid, Rutin.

The application of medicinal plants has captured the interest of researchers in recent times due to their potent therapeutic properties and a better safety profile. The prominent role of herbal products in treating and preventing multiple diseases dates back to ancient history and most of the modern drugs today originated from their significant sources owing to their ability to control multiple targets via different signalling pathways. Among them, flavonoids consist of a large group of polyphenols, which are well known for their various therapeutic benefits. Rutin is considered one of the attractive phytochemicals and important flavonoids in the pharmaceutical industry due to its diverse pharmacological activities via various underlying molecular mechanisms. It is usually prescribed for various disease conditions such as varicosities, haemorrhoids and internal haemorrhage. In this review, we have discussed and highlighted the different molecular mechanisms attributed to the various pharmacological activities of rutin, such as antioxidant, anti-inflammatory, anticancer, anti-allergic and antidiabetic. This review will be beneficial to herbal, biological and molecular scientists in understanding the pharmacological relevance of rutin at the molecular level.

Molecular modulators of celastrol as the keystones for its diverse pharmacological activities.

In the recent years, much attention has been focused on identifying bioactive compounds from medicinal plants that could be employed in therapeutics, which is attributed to their potent pharmacological actions and better toxicological profile. One such example that has come into the light with considerable interest is the pentacyclic triterpenoid, celastrol, which has been found to provide substantial therapeutic properties in a variety of diseases. In an effort to further accelerate its potential to be utilized in clinical practice in the future; along with advancing technologies in the field of drug discovery and development, different researchers have been investigating on the various mechanisms and immunological targets of celastrol that underlie its broad spectrum of pharmacological properties. In this review, we have collated the various research findings related to the molecular modulators responsible for different pharmacological activities shown by celastrol. Our review will be of interest to the herbal, biological, molecular scientist and by providing a quick snapshot about celastrol giving a new direction in the area of herbal drug discovery and development.