6‐Gingerol contents of several ginger varieties of Northeast India and correlation of their antioxidant activity in respect to phenolics and flavonoids contents

• Published in: Phytochemical analysis Vol. 34; no. 3; pp. 259 - 268
• Main Authors: Ghosh, Suparna, Das, Bhaskar, Haldar, Pallab Kanti, Kar, Amit, Chaudhary, Sushil K., Singh, Keithellakpam Ojit, Bhardwaj, Pardeep K., Sharma, Nanaocha, Mukherjee, Pulok K.
• Format: Journal Article
• Language: English
• Published: England Wiley Subscription Services, Inc 01-04-2023
• Subjects: antioxidant activity; Antioxidants; Antioxidants - chemistry; Aquatic plants; Catechols - analysis; Catechols - chemistry; Catechols - pharmacology; Correlation analysis; Flavonoids; Flavonoids - analysis; Ginger; ginger varieties; Gingerol; High performance liquid chromatography; Hydroxyl radicals; Liquid chromatography; Northeast India; Pearson's correlation; Phenols; Phenols - chemistry; Plant Extracts - chemistry; Rhizomes; RP‐HPLC; Scavenging; Sensory properties; Zingiber officinale; Zingiber officinale - chemistry; India; RP-HPLC; Pearson's correlation; Northeast India; ginger varieties; antioxidant activity
• ISSN: 0958-0344; 1099-1565
• DOI: 10.1002/pca.3201

Introduction
Ginger constitutes the rhizome part of the plant Zingiber officinale from the Zingiberaceae family. A large number of ginger varieties with high sensorial and functional quality are found in Northeast India. Hence, phytopharmacological screening of different ginger varieties is essential that will serve as a guideline in applied research to develop high‐end products and improve economical margins.
Objective
To determine the variation in total phenolics content (TPC), total flavonoids content (TFC), and antioxidant activities and correlate that with 6‐gingerol contents of different ginger varieties collected from Northeast India using Pearson's correlation analysis.
Materials and Methods
The TPC and TFC values were determined using standard methods. Antioxidant activities were measured using the 2,2‐diphenyl‐1‐picrylhydrazyl (DPPH) and hydroxyl radical scavenging assays, while reversed‐phase high‐performance liquid chromatography (RP‐HPLC) analysis was utilised for quantitative determination of 6‐gingerol content.
Results
The result revealed that ginger variety 6 (GV6) contains the highest 6‐gingerol content and TPC value showing maximum antioxidant activity, followed by GV5, GV4, GV9, GV3, GV2, GV8, GV1, and GV7. The findings also suggested that the antioxidant activity has much better correlations with TPC as compared with TFC values. Pearson's correlation analysis showed a significant correlation between 6‐gingerol contents and TPC values.
Conclusion
This work underlines the importance of ginger varieties from Northeast India as a source of natural antioxidants with health benefits.
The present study underlines the importance of ginger varieties from Northeast India as a source of natural antioxidants. The developed RP‐HPLC analysis successfully applied to estimate the variation of 6‐gingerol content among the tested ginger varieties. The in vitro antioxidant activity showed much better correlations with TPC as compared to TFC values. Pearson's correlation analysis showed a significant correlation between 6‐gingerol contents and TPC values. The findings provide confidence and research prospects to promote in different food, pharmaceutical, and supplement industries.