Abstract

The purpose of this study was to determine the effect of bio-extract produced from cabbage waste on the leaf biomass, yield and chemical compositions of volatile oils from spearmint (Mentha spicata L.) and Japanese mint (Mentha arvensis L. var. piperascens Malinv.). The spearmint and Japanese mint were grown in an open field and supplemented with three different fertilizers: bio-extract from cabbage waste, sulphur fertilizer, and a combination of sulphur fertilizer and bio-extract from cabbage waste. The plants were harvested during flowering and were analysed to determine the biomass and oil productivity. We determined that the bio-extract from cabbage waste was an effective nutrient supplement for the cultivation of spearmint and Japanese mint. For spearmint, use of the bio-extract yielded the greatest productivity of volatile oil since it resulted in the highest quantity of leaf biomass and in a high quantity of volatile oil with the greatest carvone content. For Japanese mint, the bio-extract yielded volatile oil with a menthol content equivalent to that of other supplements and we determined that application of bio-extract along with sulphur fertilizer was appropriate to enhance the biomass for Japanese mint.

Key words: Mentha spicata L., M. arvensis L. var. piperascens Malinv., bio-extract, volatile oil.