Volume 95, Issue 10 p. 1319-1327
Original Article

Effect of Solvent, Preheating Temperature, and Time on the Ultrasonic Extraction of Phenolic Compounds from Cold-Pressed Hempseed Cake

Jingbang Liang

Jingbang Liang

Department of Foods and Human Nutritional Sciences, University of Manitoba, W383 Duff Robin Building, Winnipeg, MB R3T 2N2, Canada

Search for more papers by this author
Erika Zago

Erika Zago

Department of Foods and Human Nutritional Sciences, University of Manitoba, W383 Duff Robin Building, Winnipeg, MB R3T 2N2, Canada

Search for more papers by this author
Ruchira Nandasiri

Ruchira Nandasiri

Department of Foods and Human Nutritional Sciences, University of Manitoba, W383 Duff Robin Building, Winnipeg, MB R3T 2N2, Canada

Search for more papers by this author
Rabie Khattab

Rabie Khattab

Food Science Department, Faculty of Agriculture (Saba Basha), Alexandria University, 22 Tag El-Roasa Street, P.O. Box 21531, Alexandria, Egypt

Department of Clinical Nutrition, College of Applied Medical Sciences, Imam Abdulrahman Bin Faisal University, 2835 King Faisal Road, P.O. Box 2435, Dammam 31441, Kingdom of Saudi Arabia

Search for more papers by this author
N. A. Michael Eskin

N. A. Michael Eskin

Department of Foods and Human Nutritional Sciences, University of Manitoba, W383 Duff Robin Building, Winnipeg, MB R3T 2N2, Canada

Search for more papers by this author
Peter Eck

Peter Eck

Department of Foods and Human Nutritional Sciences, University of Manitoba, W383 Duff Robin Building, Winnipeg, MB R3T 2N2, Canada

Search for more papers by this author
Usha Thiyam-Holländer

Corresponding Author

Usha Thiyam-Holländer

Department of Foods and Human Nutritional Sciences, University of Manitoba, W383 Duff Robin Building, Winnipeg, MB R3T 2N2, Canada

Richardson Centre for Functional Foods and Nutraceuticals, University of Manitoba, 196 Innovation Drive, Winnipeg, MB R3T 6C5, Canada

Usha Thiyam-Holländer

[email protected]

Search for more papers by this author
First published: 20 August 2018
Citations: 20

Abstract

The effect of different solvents (aqueous methanol [70%, v/v], aqueous acetone [80%, v/v], and a solvent mixture [MA] of aqueous methanol [70%, v/v] and aqueous acetone [70%, v/v] in a ratio of 1:1 [v/v]), preheating temperatures (140, 160, and 180°C), and times of exposure (5, 15, and 30 min) on the ultrasonic extraction of the main phenolic compounds from hempseed cake (Cannabis sativa) was investigated. A simplified new high-performance liquid chromatography (HPLC) method was developed to identify and quantify the main phenolics (namely, N-trans-caffeoyltyramine and cannabisin B) in the extracts. Two other main compounds, numbered 3 and 4, were also detected. The results showed that the nature of the extracting solvent had a significant (P < 0.05) impact on the ultrasonic extraction of phenolic compounds. The acetone extracts exhibited the highest total phenolic content (TPC), followed by MA and methanol. The preheating temperature and time of exposure enhanced the TPC for all solvents examined. The main phenolics, N-trans-caffeoyltyramine, cannabisin B, and compound 3, were positively affected by the temperature and time of exposure, irrespective of the solvents used. In sharp contrast, compound 4 appeared to be thermally sensitive: increasing preheating time and temperature decreased the yields of this compound. This study demonstrated that acetone was the most effective extracting solvent and that preheating enhanced the yield of the main phenolics.