D-Galacturonic acid is the main constituent of pectin, a naturally abundant compound. It is the monobasic acid resulting from oxidation of the primary alcohol group of D-galactose to carboxyl. D-Galacturonic acid prepared from pectin can be used to synthesize vitamin C. Native pectin is a mixture of polysaccharides, with the major component a polymer of -D-galacturonic acid. Pectin has numerous other medical and pharmaceutical uses, for example in combination with plant hemicelluloses and lignin, may be useful dietary constituents in preventing coronary heart disease, diverticular disease, ulcerative colitis, and a variety of other Western diseases. Pectin, a representative diety fibre, is a gelatinous substance derived from the cell walls of fruits and some plants and contains galacturonan, consisting of mostly long-chain D-galacturonic acids combined into units by α-1,4 linkages. As a kind of soluble dietary fiber, pectin has been proved of controlling glucose and blood lipids. It slows rapid infusion of the liquid meal into the gut by delaying gastric emptying.

Djenkolic acid (or sometimes jengkolic acid) is a sulfur-containing toxin and non-protein amino acid naturally found in Djenkol beans of the South-East Asian legumes jengkol (Archidendron jiringa). Djenkolic acid is toxic to humans, often causing kidney failure. The toxicity of djenkolic acid in humans arises from its poor solubility under acidic conditions after consumption of the Djenkol bean. The amino acid precipitates into crystals which cause mechanical irritation of the renal tubules and urinary tract, resulting in symptoms such as abdominal discomfort, loin pains, severe colic, nausea, vomiting, dysuria, gross hematuria, and oliguria, occurring 2 to 6 hours after the beans were ingested. Treatment for this toxicity requires hydration to increase urine flow and alkalinization of urine by sodium bicarbonate. Furthermore, this poisoning can be prevented when consuming Djenkol beans by boiling them beforehand, since djenkolic acid is removed from the beans.