Comparative analysis of total phenols and sulfur content in some plant organs of ramsons and two garlic species
The aim of this study was to compare total phenols and sulfur content in ramsons and two garlic species, autumn- and spring-garlic. Harvesting time for ramsons was May and for garlics was June. Total phenol content was determined by the Singleton-Rossi method, which is based on phenol oxidation using Folin-Ciocalteu reagent and spectrophotometric quantification of reduced blue-colored products. For total sulfur analysis, all sulfur molecular species were oxidised to the stable sulfate form, which was quantified by ion chromatography (HPIC). The quantity of phenolic compounds (mg phenols/g fresh sample) was the highest for the leaves of autumn-garlic (1.97mg/g), followed by leaves of spring-garlic (1.49mg/g) and ramsons (1.28mg/g). A lower phenol content was found in the bulbs: spring-garlic bulb (0.80mg/g), autumn-garlic bulb (0.48mg/g) and ramson bulb (0.46mg/g). The highest sulfur level (mg sulfur/g fresh sample) was found in spring-garlic leaf (1.10mg/g) while the quantity of sulfur for other samples were: ramsons bulb (0.93mg/g), ramsons leaf (0.74mg/g), spring-garlic bulb (0.70mg/g), autumn-garlic leaf (0.66mg/g) and autumn-garlic bulb (0.63mg/g). Levels of sulfur compounds and total phenol content in the bulbs and leaves correlated with the age of the plant. Garlic leaves can be used as a significant source of organosulfur compounds for middle to late spring.