Extraction. Two grams of chopped fresh garlic was extracted with
15 mL of 70% methanol under magnetic stirring for 2 h at room
temperature (ca. 22 C).1,2 The extract was centrifuged at 4000g for 20
min, and the supernatant was filtered through polycarbonate 0.4 μmpore
size membrane (GE Water & Process Technologies, Trevose, PA). The
extraction procedure was repeated three times, and supernatants were
pooled together. All extractions were performed in triplicate, avoiding
light exposure during the extraction process, and following extraction, they
were stored in the dark at 4 C within an hour. The weight of dry matter of
the extracts was determined and standardized to 1 mg/mL by measuring
the absorbance at 515 nm and diluting all extracts to the same optical
density with 70% methanol prior to collection of spectra.