Determination of Nicotinic Acid and Nicotinamide Forms of Vitamin B3 (Niacin) in Fruits and Vegetables by HPLC Using Postcolumn Derivatization System

Abstract

Background and Objective: Vitamin B3 is an important water-soluble vitamin that occurs in two forms in foods, nicotinic acid and nicotinamide. In the literature, the studies of vitamin B3 are based on the analysis of total vitamin B3 in foods. This study aimed to determine the nicotinic acid and nicotinamide contents in fruits and vegetables and to identify the best fruits and vegetables suitable for vitamin B3 intake. Materials and Methods: A total of 67 samples of fruits and vegetables were collected from Istanbul, Turkey. The nicotinic acid and nicotinamide contents of 28 fruits and 39 vegetables were determined by HPLC using a postcolumn derivatization system. This is the first comprehensive report on the vitamin B3 profiles of fruits and vegetables commonly consumed in Turkey. Results: A low level of nicotinic acid and a high level of nicotinamide were found in fruits. Vegetables exhibited the highest amount of nicotinic acid (66%), while the highest amount of nicotinamide was noted in fruits (47%). The nicotinic acid and nicotinamide contents of fruits ranged from 12-100 and 0-88%, respectively. However, the nicotinic acid and nicotinamide contents of vegetables ranged from 6-98 and 3-94%, respectively. Conclusion: Food composition tables need to be expanded and improved regarding the quantity and quality profiles in food composition databases through the collection and analysis of foods. This study highlights the importance of publicly accessible food composition databases for estimating nicotinic acid and nicotinamide intake and provides a reference for tools that are available globally.