TITLE:
Key Organic Acids in Indigenous Plants in Thailand
AUTHORS:
Benyathip Sukontaprapun, Somsri Charoenkiatkul, Parunya Thiyajai, Monruedee Sukprasansap, Preecha Saetang, Kunchit Judprasong
KEYWORDS:
Indigenous Plants, Organic Acids, Ascorbic Acid, Total Acidity
JOURNAL NAME:
American Journal of Plant Sciences,
Vol.10 No.10,
October
25,
2019
ABSTRACT: Organic acids had various health benefits such as
citric acid can inhibit stone formation and break up beginning of small kidney
stone. On the other hand, some organic acid showed negative health effects such as oxalic acid acts as
anti-nutrients and can cause kidney stone. Most of Thai indigenous plants had
sour taste; however general people believed that sour taste of plants could
contain high ascorbic acid. In addition, there is limit report of organic acids
and ascorbic acid in Thai indigenous plants. This study determined organic
acids, ascorbic acid, pH, and total acidity in indigenous plants. Forty samples
of 29 types of indigenous plants were analyzed. Results showed that young
leaves of Cratoxylum formosum found the highest succinic acid (2454 ± 91 mg/100g fresh weight, FW) and high
ascorbic acid (142 ± 35 mg/100g FW). Fruits of Antidesma ghaesembilla had high citric
acid levels (5161 ± 109 mg/100g FW) but contained very low ascorbic acid (2
mg/100g FW). The sum of organic acids had significant and inverse correlations
with pH (r = -0.680) and positive with total acidity (r =
0.672) but was not significantly correlated for ascorbic acid (r =
0.536). The sour taste of plants could derive from the sum of organic, citric,
and formic acids, but not other organic and ascorbic acids. Against traditional
belief, plants having a strong sour taste may not contain significantly high
amounts of ascorbic acid.