Identification of tropolone derivatives from black turmeric (Curcuma caesia Roxb.) essential oil and their application in postharvest management of mangoes (Mangifera indica L.).

Abstract

The present study focused on the identification of tropolone derivatives in the essential oils of black turmeric (Curcuma caesia Roxb.). Cyclohepta[b]furan-2-ones and azulene compounds to which tropolone might be the precursor were detected in the essential oils. Predominant compounds present were curzerenone (51.11-70.26%), curzerene (1.85-3.62%), germacrone (3.64-12.54%) and eremanthin (3.9-5.08%). The efficacy of extracted essential oil (BTC) and tropolone (TC) on postharvest quality of edible coated mangoes was studied during storage at 28 ± 2 °C (RT) and 9 ± 2 °C (LT). Treated mangoes showed lower water loss and higher firmness than control mangoes at both temperatures. β-carotene and sugar content increased in the mangoes stored at RT indicating ripening with higher TSS (Total Soluble Solids) and lower acidity (p < 0.05). Phenolic and flavonoid concentration was retained in the coated mangoes at LT. The study concluded that the BTC and TC mangoes at LT extended the shelf life with delayed ripening.