Optimized Extraction and Characterization of Folates From Date Palm Fruits and Their Tracking During Fruits Wine Fermentation

Abstract

Folates belong to the essential B vitamins group and participate in one-carbon metabolism. Date palm fruits (Phoenix dactilyfera L. family Arecaceae) are consumed by millions of people and are good sources of folates. To date, no detailed study has been carried out on suitable methods for folate extraction from date palm fruits. In the present study, an experimental design using response surface methodology (RSM) was used to maximize the extraction yield of folates from date palm fruits by including enzymatic depectinization. By applying this new strategy and a UHPLC-MS/MS technique for analysis, total folate and different folate vitamers of three cultivars of date palm fruits (Muzafti, Zahdi, and Rubai), brewer's yeast, and fermented date wine were analyzed. The optimized extraction conditions of folates from date palm fruits were found to be a pectinase activity of 47.7 U, an incubation temperature of 40°C, and an incubation time of 38 min, which yielded a total folate content of 191–301 μg/100 g. In brewer's yeast, the extracted total folate content was very high (4,870 μg/100 g), and, in the resulting date wine, it reached a maximum of 700 μg/L on the fifth day. The predominant folate vitamers in date fruit and fruit wine were 5-formyltetrahydrofolate (5-CHO-THF) and 5-methyltetrahydrofolate (5-CH3-THF). During date palm fruit fermentation for up to 8 days, the 5-CHO-THF content gradually decreased by 20%, while 5-CH3-THF increased linearly from day 1 to day 5 (y = 0.058 x + 0.0284, R2 = 0.9614). This study shows that date palm fruit and fruit wine are excellent sources of folate, and further study can be focused on different methods to improve folate stability during wine storage.

An improved folate stable isotope dilution assay of unexploited food sources from Brazil

“…Also, the date palm fruits, an important commercial crop cultivated in Arab countries, have been found to contain a substantial folate content, ranging from 191 to 301 μg/100 g FW with 5-CHO-H 4 folate as the main vitamer, constituting over 90% of the total folate content ( 24 ).…”

Application of Cyclocarya paliurus–Kiwifruit Composite Fermented to Enhance Antioxidant Capacity, Flavor, and Sensory Characteristics of Kiwi Wine

“…RSM is a statistical method to optimize projects and improve experimental efficiency. This method has been applied in the wine fermentation of fruits such as cactus pear, mango, and date palm in early reports [ 18 , 19 , 20 ]. The optimum C. paliurus –kiwi winemaking condition (data provided in the supplementary material ) was optimized by RSM, and alterations in the physicochemical properties and antioxidant activity of wine were analyzed according to this condition.…”

Fermented traditional wine from palm trees: microbial, nutritional attributes and health impacts

“…They linked the protective effects to the presence of sugar alcohol and phytochemical constituents (allose, galactitol, rhamnose, d-tagatose, cymarin, and quinic acid) of RPW (Erukainure et al, 2019b;Erukainure et al, 2019c). Meng et al (2021) optimized the extraction of folate from date palm (Phoenix dactilyfera L.) fruits and reported their characteristics during fruits wine fermentation using response surface methodology (RSM). They reported a maximum level for the total folate in the date palm wine of 700 μg/L after fermentation, and the sugar content and calories were drastically decreased.…”