Temporal Extraction, Extracting Solvent Concentration and Extract Concentration Impact on Antibacterial Activity of Garlic

Abstract

Pharmaceutical companies worldwide have celebrated success producing synthetic derivatives of therapeutic plant extracts. These extracts have remained a primary treatment option globally. In this study, the impact of temporal extraction, extracting solvent and extract concentration on antibacterial potency of garlic was evaluated. Garlic extract was prepared according to these parameters; extraction period (1-2;3 days), solvent concentration (50%, 80%, 100%), reconstituted extract concentration (50mg/ml, 100mg/ml) and antibacterial activity established using the well diffusion method. Ethanol is a good extracting solvent but this is concentration dependent. Garlic extract showed varying antibacterial potency based on extraction parameters against Staphylococcus aureus. Empirically, a linear relationship existed between solvent concentration, extraction period (1-2 days) and antibacterial activity of garlic for as concentration of extraction solvent increased (80%-100%), with extraction period (1-2 days) the antibacterial activity also increased. It was also observed that with equal mass of plant material for extraction and equal volume of extracting solvent, 24-hours extraction period empirically produced more bioactive compounds that caused inhibition than 48-hours extraction time. Also with equal mass of material for extraction and volume of extracting solvent over a period of extraction (1-3 days), 80% ethanol produced more bioactive compounds that cause inhibition. From the findings, it appeared that longer extraction time (for fixed quantity of material to be extracted and fixed volume of extracting solvent) allowed other factors to influence bioactive compounds that caused inhibition. In addition, for a fixed volume of extracting solvent, weight of plant material for extraction (eg 20g-30g) within solubility limits is proportional to the availability of bioactive compounds particularly for 1-day extraction. The work also found that there’s extracting solvent concentration dependent reconstituted extract concentration inhibition effect and that if effective solvent concentration is considered a constant, then reconstituted extract concentration would be directly proportional to inhibition zone. Further research on temporal extraction and solvent concentration effect backed by correlation studies and statistical analysis is necessary.