Purpose: The aim of the study to formulate and statistically optimize sitagliptin-loaded eudragit nanoparticles (SIT-NPs) and evaluate the in-vitro pharmaceutical quality and in-vivo anti-diabetic assessment. Method: SIT-NPs were prepared by using combination method of solvent evaporation and nano-precipitation techniques. The influence of different independent variables as eudragit RL100 concentration (%), tween 80 concentration (%) and sonication time (min) were evaluated on dependent variables like particle size (nm), drug loading (%) and in-vitro drug release (%). Further, the optimized formulation was evaluated for surface morphology, CLSM, ex-vivo permeation study and in-vivo anti-diabetic activity and stability study. Results: The developed SIT-NPs formulations showed particle size range (135.86–193.45 nm), drug loading (6.36–8.76%) and prolonged drug release over 24 h. The prepared SIT-NPs were found to be nearly spherical with smooth surface. The comparative in-vitro release study and CLSM study results revealed that SIT-NPopt showed significantly (p < .05) enhanced release and permeation as compared to SIT free solution (SIT-Fs). The in-vivo anti-diabetic assessment revealed that SIT-NPopt able to reduce the blood sugar level (BSL) for a prolonged period of time. Further, the stability study data showed the formulations were found stable at both temperature and having the shelf life of 488 d. Conclusions: This research has shown that SIT-NPs based on experimental design offers a new and better approach to delivering SIT, thus encouraging further development of this formulation.

Methicillin-Resistant Staphylococcus aureus (MRSA) is a Gram-positive bacterium which causes community and hospital-acquired infections. Synthetic drug/antibiotic treatment for MRSA-related infections is becoming less effective and natural products may be an emerging new alternative for future antibacterial drug development. Alkaloids are a class of natural compounds which are known for their phytochemistry and pharmacology. This review focuses on 32 alkaloids isolated from various plants that showed marked antibacterial activity against MRSA by acting through different mechanisms such as inhibition of pyruvate kinase, Quorum quenching effect, alteration in efflux pump in MRSA and intercalating of bacterial DNA, to name just a few. In addition, the use of recent plant alkaloids against clinical isolates of MRSA has also been discussed.