Chemoprotective properties of glucosinolate containing plants evaluated utilizing an Agrobacterium tumefaciens-potato assay
S.G. Harvey, H.N. Hannahan, and C.E. Sams
Proceedings of 26th International Horticultural Congress. Volume of Abstract . Toronto, Canada, 11-17 August, 2002. Abstract S09-P-176. pp. 265.
2002
บทคัดย่อ
The chemoprotective benefits associated with the consumption of broccoli (Brassica oleracea L. [Botrytis Group]) have been linked to metabolites derved from glucosinolates (GS). Glucosinolates are catabolized into isotyiocyanates (ITC) and other breakdown products. Isothiocyanates induce the production of detoxifying phase 2 enzymes, which protect tissues from malignancy. To screen GS-containing plants for chemoprotective activity, an Agrobacterium tumefaciens-potato disk assay was preformed. Seed of sixteen species of GS containing plants, representing two families and six genera, were extracted with 90 0C-deionized water. Extracts were centrifuged and filter-sterilized. Potato disk were cut from white Russet Burbank potatoes and placed on petri plates containing water agar for hydration. Extracts were applied to the surface of the potato disks. Myrosinase, an enzyme that breaks down GS into ITCs, was also added to the potato disks. Disks were incubated at 25 oC for 24 hr. disks were then inoculated with A. tumefaciens to illicit tumor formation and incubated for 20 days. After incubation, disks were stained using diluted Lugol’s solution and tumors were counted. All plant extracts provided significant inhibition of tumor formation (P<0.01). upland cress (Barbarea verna L. ) extract provided the most protection with 74% ingibition of tumor formation. Brusels sprouts (Brassica oleracea L.[Gemmifera group]) exhibited the least amount of inhibition at 44.6%. A compound known to inhibit growth of human cancer cells , cAMP, demonstrated 60% inhibition