Cactus

Polyphenol

Biology

Betanin

Biochemistry

Botany

Food science

Betalain

Organic chemistry

Pigment

Antioxidant

Kaempferol

Chemistry

Berry

Quercetin

DPPH

Food Research International

Berry cactus fruit (Myrtillocactus geometrizans) is an endemic cactus fruit from Mexico and is a rich source of phytochemicals, primarily betacyanins, betalains and polyphenols. However, only a few studies have been performed to evaluate the changes in the levels of these compounds in berry cactus fruits during post harvest storage. Berry cactus fruits were treated with a sodium caseinate (Na-Cas) based edible coating plasticized with sorbitol (S) and glycerol (G), and their phytochemical contents were evaluated. Control (C), Na-Cas(S) and Na-Cas(G) fruits were packed in clam shell boxes and stored at 5 ± 1 °C for 15 days. Betacyanins, betaxanthins, total polyphenols, their in vitro antioxidant activity, as well as α-amylase and α-glucosidase inhibitory activities were estimated during storage at 0, 7 and 15 days. Polyphenol levels declined from an initial 3500 mg/100 g of dry fruit by over 50% after 7 days of storage. By contrast, total betalain levels remained steady during the 15 days of storage. Antioxidant capacity, as measured by DPPH (1,1-diphenyl-2-picryl-hydrazyl) radical scavenging, was maintained in berry cactus fruit extracts during storage. Edible coatings did not have any effects on the antioxidant capacity. Berry cactus polyphenols were also strong inhibitors of α-amylase and α-glucosidase activities. Portulacaxanthin II and III, indicaxanthin, vulgaxanthin I and III, 3-methoxytyramine-betaxanthin, arginine-betaxanthin, betanidin, dopa-betaxanthin, betanin, phyllocactin, and three other unknown compounds were identified as betalains. As well, a catechin derivative, epicatechin, epigallocatechin, kaempferol, myricitrin, quercetin 3-O-β-glucoside, isorhamnetin 3-glucoside and a kampferol diglycoside were identified as polyphenols.

Effect of a sodium caseinate edible coating on berry cactus fruit (Myrtillocactus geometrizans) phytochemicals