Chemical composition of seed essential oils from Algerian Nigella sativa extracted by microwave and hydrodistillation

Abstract

Extraction of essential oil from Nigella sativa seed collected at two locations in the Sahara desert, Timimoun (T) and Adrar (A), has been conducted by hydrodistillation (HD) and a microwave distillation process (MD). The composition of the volatile oil was investigated by capillary gas chromatography and gas chromatography-mass spectrometry. Using the hydrodistillation, active compounds such as p-cymene (8.9 and 7.2% in T and A, respectively), 4-terpineol (0.6-8.9%), thymohydroquinone (6.1-12.2%), thymoquinone (1.6-21.8%), carvacrol (12.9-12.9%), carvone (4.4-0.3%) and thymol (1.5-0.7%) were the major components, representing more than 36% (T) and 64% (A) of the oils. For the microwave distillation, p-cymene (28.1% and 32.0% in T and A, respectively), 4-terpineol (3.4-2.0%), thymohydroquinone (0.7-1.1%), thymoquinone (10.8-24.6%), carvacrol (3.0-6.0%), and thymol (0.3-0.3%) represent respectively 46.1% and 66.0% of the T and A oils.

Health-promoting value and food applications of black cumin essential oil: an overview

“…Seeds or their oils were claimed for medicinal applications dating back to the ancient Egyptians, Greeks and Romans (Benkaci- Ali et al 2007). In Islamic literature, Nigella sativa is considered as one of the greatest forms of healing medicine.…”

“…2). Seeds are commonly known as black seed, black cumin (English) and habbatu sawda or habbatu el baraka (Arabic) (Benkaci- Ali et al 2007). …”

Essential Oils and New Antimicrobial Strategies

“…Hydrodistillation using the Clevenger-type apparatus is the most commonly used technique for laboratory-scale extraction of essential oils [37][38][39].…”

“…The chemical profiles of these oils were compared by gas chromatography-mass spectrometry (GC-MS) and no major changes were observed between them [43]. Other recent examples are microwave extraction of Nigella sativa seeds [39], Carum ajowan (ajowan), C. cyminum and Illicium anisatum (star anise) [44].…”

Optimization of Microwave-assisted Extraction of Thymoquinone from Nigella sativa L. Seeds

“…Kiralan et al [18] investigated the influence of extraction methods including MAE on the physicochemical properties and stability of black cumin seed oil (Nigella sativa), but bioactives were out of the scope of that study. Additionally, there have been studies investigating the extraction of essential oils and volatiles from black cumin seed by microwave-and hydro-distillation, the results of which revealed that microwave-assisted distillation provided a higher yield in shorter processing time with lower energy consumption [13,19]. Fig.…”