ABSTRACT
Garlic is a well-known example of natural self-defence system consisting of an inactive substrate (alliin) and enzyme (alliinase) which, when combined, produce highly antimicrobial allicin. Increase of alliinase stability and its activity are of paramount importance in various applications relying on its use for in-situ synthesis of allicin or its analogues, e.g., pulmonary drug delivery, treatment of superficial injuries, or urease inhibitors in fertilizers. Here, we discuss the effect of temperature, pH, buffers, salts, and additives, i.e. antioxidants, chelating agents, reducing agents and cosolvents, on the stability and the activity of alliinase extracted from garlic. The effects of the storage temperature and relative humidity on the stability of lyophilized alliinase was demonstrated. A combination of the short half-life, high reactivity and non-specificity to particular proteins are reasons most bacteria cannot deal with allicin's mode of action and develop effective defence mechanism, which could be the key to sustainable drug design addressing serious problems with escalating emergence of multidrug-resistant (MDR) bacterial strains.
Subject(s)
Carbon-Sulfur Lyases/metabolism , Chemical Phenomena , Disulfides/metabolism , Garlic/enzymology , Sulfinic Acids/metabolism , Anti-Bacterial Agents/pharmacology , Bacteria/drug effects , Bacteria/ultrastructure , Biocatalysis/drug effects , Buffers , Disulfides/chemistry , Enzyme Stability/drug effects , Freeze Drying , Hydrogen-Ion Concentration , Kinetics , Microbial Sensitivity Tests , Microbial Viability/drug effects , Stereoisomerism , Sulfinic Acids/chemistry , Temperature , Time FactorsABSTRACT
Many new therapeutic candidates and active pharmaceutical ingredients (APIs) are poorly soluble in an aqueous environment, resulting in their reduced bioavailability. A promising way of enhancing the release of an API and, thus, its bioavailability seems to be the use of liquid oil marbles (LOMs). An LOM system behaves as a solid form but consists of an oil droplet in which an already dissolved API is encapsulated by a powder. This study aims to optimize the oil/powder combination for the development of such systems. LOMs were successfully prepared for 15 oil/powder combinations, and the following properties were investigated: particle mass fraction, dissolution time, and mechanical stability. Furthermore, the release of API from both LOMs and LOMs encapsulated into gelatine capsules was studied.
