1998: Supermarkets were put on alert afterblack widow spiders were discovered in a shipment of African grapes
. 1999: It was reported that 89 different species of parrot were under threat from extinction.
van Velden decided to investigate the authenticity of those claims, and to analyze and compare certain South African grapes and wines for the presence of possible biological active ingredients to explain some of the cardioprotective effects, as well as their anti-carcinogenic chemopreventive power.
Also, a chemical analysis was done for the identification of the antioxidant flavonoids-quercitin, catechin and epicatechin-and to determine whether salicylic acid and acetyl salicylic acid (aspirin) were present in South African grapes and wines.
The analysis indicated that South African grapes and wines do contain significant amounts of quercitin, catechin and epicatechin, which may, in part, be responsible for the protective effect against cancer and certain other chronic and degenerative diseases (see Tables 1 and 2).