1.Low material cost,own plant for processing and storage, 2.high quality, 3.competitive ... Vitamin C B A, eight kinds of vitamins and phosphorus iron, etc, and many mineral elements3. Anthocyanin4. Cellulose5. Selenium ... some antibiotics bring to human body 3.Selenium and iron are the necessary antifatigue, anti-aging, hematinic elements, ... supplying. 2013 Chinese Yunnan purple sweet potatoes for sale