Juneberry (Amelanchier alnifolia) is a shrub with edible berry-like fruit commonly found across the Northern Great Plains of North America and widely used by Native Americans as a medicinal plant. This study was an effort to assess the chemopreventive contents of juneberry extracts in ethanol by measuring the total phenolic content, orthophenolic content, DPPH radical scavenging activity, ABTS radical cation decolorization assay, and cytoprotective effects on HepG2 cells. The total phenolic content upon treatment with Folin-Ciocalteu's reagent ranged from 0.2261 ± 0.0031 to 19.311 ± 1.651 mg.g -1 tannic acid equivalents. Orthophenolic content quantified by monitoring the bathochromic shifts upon reacting with sodium molybdate ranged from 0.12 ± 0.03 to 2.38 ± 0.15 mg.g -1 of FW. Antioxidant activity using DPPH assay ranged from 50.08 ± 0.77 to 98.60 ± 1.12%, in contrast to quercetin dihydrate with an activity of 86.20 ± 0.05%. ABTS radical scavenging assay produced inhibition from 1.90 ± 0.11 to 60.25 ± 1.65% as opposed to 6-hydroxy-2, 5, 7, 8-tetramethylchroman-2-carboxylic acid (Trolox) with an inhibition of 94.03 ± 0.21% . HepG2 cells treated with 100 µg/µL of sample WC2B showed 56% cell-viability against tert-Butyl hydroperoxide in comparison to quercetin dihydrate which showed 90% cytoprotection. Total phenolic content and orthophenolic content in juneberries from 2012 were higher than in juneberries obtained from the 2013 and 2014. Similarly fruit grown in the wild showed significantly higher antioxidant activity and phenolic content than those grown in domestic cultivars.

Amelanchier alnifolia Nutt. (Juneberry, Saskatoon berry or Serviceberry) fruit historically played an important role as fresh or dried food and as a medicinal staple in the Mandan, Hidatsa, and Arikara Tribal Nations. Natural Juneberry stands were lost during the creation of Sakakawea Reservoir on the Fort Berthold Reservation. Reintroduction of the Juneberry is important to the tribal communities. Therefore, the impact of water and fertilizer supplementation was explored in two mature Juneberry cultivar (Honeywood, Martin, and Smokey) plantings and a seedling windbreak planting. Yield was examined in three consecutive years with three treatments: (1) natural conditions (control; no additional water or fertilizer); (2) irrigation during flowering and fruit ripening period (irrigated); and (3) fertilization plus irrigation during flowering and fruit ripening period (fertilized). Yield varied from 5 to 258 g/0.03 m−3 across locations, treatments, and years. There was no difference in yield across locations and treatments in year one. Yield was greater in the second year than first year, but not different across locations or treatments. The fertilized treatment showed increased yield in the third year in contrast to irrigated treatment across locations. New plantings can be established more economically using seedling material and the yield increased if watered and fertilized during fruit development.