Bioactive vegetables integrated into ethnic “Three Sisters Crops” garden targeting foods for type 2 diabetes-associated health disparities of American Indian communities  Lokesh K. Mishra, Jacob Walker-Swaney, Dipayan Sarkar, Kalidas Shetty  Journal of Ethnic Foods  Volume 4, Issue 3, Pages 163-171 (September 2017) DOI: 10.1016/j.jef.2017.08.007 Copyright © 2017 Korea Food Research Institute Terms and Conditions

Fig. 1 The ethnic “Three Sisters Crops” model of Mesoamerica (polyculture of corn, bean, and squash) (A). In “Three Sisters Crops” model, corn and beans are generally grown in same mounds and squash are planted in mounds of alternate rows (B). Corn provides the stalk for the bean to climb, while bean helps to build the soil nitrogen profile (natural nitrogen fixing), and squash with larger leaves acts as mulch helping to smother weed and preserve soil moisture (C). In ethnic American Indian diet, “Three Sisters Crops” also complement each other and provide diverse dietary and health benefits (D). Journal of Ethnic Foods 2017 4, 163-171DOI: (10.1016/j.jef.2017.08.007) Copyright © 2017 Korea Food Research Institute Terms and Conditions

Fig. 2 Layout of the “Three Sisters Crops” garden with seven targeted vegetables and tobacco. Four vegetables from Mesoamerican origin (potato, and three classes of pepper, i.e., poblano, jalapeno, and bell) and three vegetables from Eurasian origin (beetroot, carrot, and kale) were targeted and integrated into ethnic “Three Sisters Crops” based garden model. Corn, bean, and squash (“Three Sisters Crops”) were planted in mounds based on traditional cropping design, while all targeted vegetables were grown in rows adjacent to the “Three Sisters Crops” design. These vegetables with rich bioactive profiles were targeted and integrated for human health relevant value added diversification of ethnic “Three Sisters Crops” garden model. Journal of Ethnic Foods 2017 4, 163-171DOI: (10.1016/j.jef.2017.08.007) Copyright © 2017 Korea Food Research Institute Terms and Conditions

Fig. 3 Total soluble phenolic content (mg/g fresh weight) of seven targeted vegetables integrated into “Three Sisters Crops” garden model. Different alphabets represent significant differences at p < 0.05 probability level. Total soluble phenolic content of food crop is a good indicator for understanding the human health relevant phenolic bioactives of plant-based foods including ethnic foods, especially for their potential dietary applications against chronic diseases. FW, fresh weight. Journal of Ethnic Foods 2017 4, 163-171DOI: (10.1016/j.jef.2017.08.007) Copyright © 2017 Korea Food Research Institute Terms and Conditions

Fig. 4 Total antioxidant activity (ABTS-based free radical scavenging assay) of seven targeted vegetables integrated into “Three Sisters crop” garden model. Different alphabets represent significant differences at p < 0.05 probability level. Total antioxidant activity (based on ABTS radical scavenging assay) result provides information on antioxidant potentials of plant-based foods including ethnic foods and its potential benefits against chronic oxidative stress when consumed as part of a diet. The antioxidant assay based on ABTS free radical scavenging activity also provides better response for water soluble antioxidant fractions of the plant-based foods. ABTS, 2,2′-azino-bis(3-ethylbenzthiazoline-6-sulphonic acid). Journal of Ethnic Foods 2017 4, 163-171DOI: (10.1016/j.jef.2017.08.007) Copyright © 2017 Korea Food Research Institute Terms and Conditions

Fig. 5 Total antioxidant activity (DPPH-based free radical scavenging assay) of seven targeted vegetables integrated into “Three Sisters Crops” garden model. Different alphabets represent significant differences at p < 0.05 probability level. Total antioxidant activity (based on DPPH free radical scavenging assay) result provides information on antioxidant potentials of plant-based foods including ethnic foods and its probable benefits against chronic oxidative stress when consumed as part of a diet. Along with ABTS, DPPH free radical scavenging assay helps to compare antioxidant potentials of different plant-based foods including targeted seven vegetables of the current study. ABTS, 2,2′-azino-bis(3-ethylbenzthiazoline-6-sulphonic acid); DPPH, 2,2-diphenyl-1-picrylhydrazylradical. Journal of Ethnic Foods 2017 4, 163-171DOI: (10.1016/j.jef.2017.08.007) Copyright © 2017 Korea Food Research Institute Terms and Conditions

Fig. 6 Dose-dependent (undiluted, half, and one-fifth) response in α-glucosidase inhibitory activity (%) of seven targeted vegetables integrated into “Three Sisters Crops” garden model. Different alphabets and *,†,‡ signs represent significant differences at p < 0.05 probability level separately for individual dilution. α-Glucosidase is a key digestive enzyme responsible for carbohydrate metabolism in vivo. Inhibiting the activity of this enzyme, the release and absorption of glucose in the bloodstream can be delayed, which is critical for managing postprandial glucose homeostasis. Therefore, in vitro results of α-glucosidase inhibitory activity of vegetables provide sound biochemical rationale for their potential anti-hyperglycemic functions relevant for type 2 diabetes management. * Significant differences at p < 0.05 probability level. Journal of Ethnic Foods 2017 4, 163-171DOI: (10.1016/j.jef.2017.08.007) Copyright © 2017 Korea Food Research Institute Terms and Conditions

Fig. 7 Angiotensin-I-converting enzyme (ACE) inhibitory activity (%) of seven targeted vegetables integrated into “Three Sisters Crops” garden model. Different alphabets represent significant differences at p < 0.05 probability level. Hypertension is a common risk factor associated with type 2 diabetes and inhibition of ACE is an important target for therapeutic strategies to control hypertension. Based on the results of in vitro ACE inhibitory activity of vegetables, it can be further targeted for clinical or animal model-based trial or to design healthy ethnic food models to manage hypertension commonly associated with type 2 diabetes. Journal of Ethnic Foods 2017 4, 163-171DOI: (10.1016/j.jef.2017.08.007) Copyright © 2017 Korea Food Research Institute Terms and Conditions