STUDIES ON EXTRACTION OF D-LIMONENE ESSENTIAL OIL FROM CITRUS WASTE

Extraction of D-limonene essential oil

Abstract

Citrus waste, including discarded orange peels, lemon peels, and citrus limetta peels, poses both environmental and economic

concerns. However, there is a valuable chemical within this waste that could potentially be recovered: D-limonene essential oil, which

is highly sought-after for a variety of applications including food, fine chemicals, and medicine[1]. Present work specifically focuses

on the recovery of D-limonene essential oil from citrus limetta waste through an exploratory analysis using the Taguchi method with

Minitab V20.0. The study assessed the impact of parameters such as feed/solvent ratio, temperature, extraction time, enzyme

concentration, and maceration time. The optimal conditions for D-limonene essential oil extraction were found to be a 100g

feed/150ml solvent ratio, 30-minute extraction time, and 70°C for solvent extraction, resulting in a total oil yield of 4.2ml/100g feed.

Enzyme-assisted extraction produced an optimal total oil yield of 1.6ml/100g feed under 6g enzyme concentration, 40-minute

maceration time, and 40°C temperature conditions. The presence of D-limonene was confirmed through Iodine testing and FTIR

spectroscopy. This study demonstrates the potential for enzyme-assisted extraction as a sustainable and eco-friendly process for

obtaining high-grade natural products without the use of chemical solvents and in less time.