摘要
Recent trends in health and wellness as well as fossil fuel dependent markets provide opportunities for agricultural crops as renewable resources in partial replacement of synthetic components in food, clothing and fuels. This investigation focused on purple-fleshed industrial sweetpotatoes (ISPs), a crop which is used for industrial purposes because it produces relatively high quantities of antioxidants in the form of anthocyanins as well as high starch content for potential hydrolysis into fermentable sugars. Laboratory extraction and enzymatic hydrolysis studies were conducted on purple-fleshed ISPs in order to evaluate the effects of solvent, extraction temperature and solid loading on recovery of anthocyanins and fermentable sugars. Total monomeric anthocyanin and phenolic concentrations of the extracts were measured. Residual solids from anthocyanin extraction were subsequently hydrolyzed for sugar production (maltotriose, maltose, glucose and fructose). Extraction temperature of 80 °C using acidified methanol at 3.3% (w/v) solid loading showed the highest anthocyanin recovery at 186.1 mg cyanidin-3-glucoside/100 g fw. Acidified solvents resulted in 10–45% and 16–46% more anthocyanins than non-acidified solvents of ethanol and methanol, respectively. On average, glucose production ranged from 268 to 395 mg/g dry ISP. Solid residues that went through extraction with acidified ethanol at 50 °C at 17% (w/v) solid loading had the highest average production of glucose at 395 mg/g dry ISP. Residues from methanol solvents had lower glucose production after hydrolysis compared to those of ethanol based extraction. Fermentation of produced sugars from ISP residues was limited, where 38% less ethanol was produced from extraction residues compared to treatments that did not undergo initial extraction. Overall, purple-fleshed ISPs are amenable to anthocyanin and phenolic extraction, making it a suitable substrate for development of industrial colorants and dyes. However, more research is needed to obtain a suitable extraction point when trying to achieve a high recovery of anthocyanins and effective starch conversion to fermentable glucose.
摘要译文
在卫生和健康，以及化石燃料的依赖市场的最新趋势提供农作物在食物中合成成分的部分替代可再生资源的机会，服装和燃料。本次调查集中在紫肉工业sweetpotatoes商（ISP），用于工业目的，因为它产生较高量的抗氧化剂的花青素的形式，以及高淀粉含量的潜在水解成可发酵糖。实验室萃取和酶水解研究是为了评估的溶剂的影响在紫肉的ISP进行的，提取温度和固含量的花青素和发酵糖的恢复。提取物的总单体花青素和酚类的浓度进行测定。来自花青素提取残留固体随后水解糖生产（麦芽三糖，麦芽糖，葡萄糖和果糖）。用酸化的甲醇在3.3％（重量/体积）固体负荷表现出最高的花青素恢复在186.1毫克矢车菊素-3-葡萄糖苷/ 100g的FW为80℃萃取温度。酸化的溶剂导致比的乙醇和甲醇，分别非酸化溶剂10-45％和16-46％的花青素。平均来说，葡萄糖生产范围从268至395毫克/克干的ISP。固体残留物通过萃取去用酸化乙醇在50℃下在17％（重量/体积）固体装载有最高的平均生产葡萄糖的395毫克/克干的ISP。从甲醇溶剂残留有较低的葡萄糖生产水解后相比，乙醇提取基础。从ISP残渣中糖的发酵是有限的，其中，少38％乙醇提取，从生产残留物相比，没有经过最初的提取处理。总体而言，紫肉的ISP是适合于花青素和酚提取，使之在合适的基材用于工业的着色剂和染料的发展。然而，需要更多的研究努力实现高回收率花青素和有效淀粉转化为可发酵的葡萄糖时，得到合适的提取点。
E. Nicole Bridgers[a]; Mari S. Chinn[b]; Van-Den Truong[c]. Extraction of anthocyanins from industrial purple-fleshed sweetpotatoes and enzymatic hydrolysis of residues for fermentable sugars[J]. Industrial Crops and Products, 2010,32(3): 613–620