Effect of extraction time on antioxidants and bioactive volatile components of green tea (Camellia sinensis), using GC/MS

Abstract

Two green tea types, leaf grade and sanding, were extracted at different time intervals: 20, 40, and 120 min at a constant temperature of 50°C. The extracts were analyzed by GC/MS technique. The major compounds identified were myristic acid, palmitic acid, stearic acid, oleic acid, 1H-purine-2,6-dione, caffeine, linoleic acid, diethyl ester, and 1H-purine-6-amine. Stearic acid, palmitic acid, linoleic acid, and myristic acid were more abundantly present in the leaf-grade variety than sanding. However, some levels of acetic acid, cyclobutanol, hexadecanoic acid, octadecanoic acid, 9-octadecenoic acid, and caffeine were also found in both the tea types. Most of the volatile compounds were detected between 20–40-min time of extraction. The 40-min time of extraction also showed the maximum content of polyphenols and antioxidants in both the tea types. Thus, 40 min was suggested as the most suitable time for maximum extraction of bioactive volatiles, antioxidants, and polyphenols from green tea.

Keywords:

• Camellia sinensis
• extraction
• GC–MS
• antioxidants
• polyphenols

Public Interest Statement

The article reports about the extraction time required to release maximum bioactive components from green tea. This could be helpful for industrialists to optimize the process for extracting tea components. In the present era, the general public is more prone to various diseases like cancer, diabetes, cardiovascular diseases and others. Green tea is reported for its health-promoting activities such as anti-proliferative, anti-hypertensive, anti-atherosclerotic, hypo-cholesterolemic, and hypo-lipidemic activities, which are mostly attributed to the flavonoids, antioxidants, and total phenols present in it. The article reports that processing time effects the type and amount of compounds released from green tea. The consumers can process green tea at the domestic level, at suggested time for extraction, and can avail maximum health benefits from it.

Competing interests

The authors declare no competing interest.

Acknowledgment

The authors are highly thankful to the Department of Biotechnology, Government of India.

Additional information

Funding

Funding. The authors received no direct funding for this research.

Notes on contributors

Adil Gani

Adil Gani is an assistant professor in the Department of Food Science and Technology, University of Kashmir, Srinagar. He is currently working on different projects viz. Nutraceutical potential of β- glucan, its utilization for making functional foods, and as an encapsulating material for target delivery of probiotics. Wheat flour modification by bacterial, enzymatic, and chemical interventions to combat coeliac disorders. Extraction of resistant starch from rice and horse chestnut and its utilization as an encapsulating agent for targeted delivery into the colon. Safety, Quality, and Nutraceutical Status of Kradi—A traditional Dairy-based fermented food of Himalayan Regions of J&K. Apart from this, he is also associated in teaching, training, and other related activities of the University/Department.