Mulberries are consumed either freshly or as processed fruits and are traditionally used to tackle several diseases, especially type II diabetes. Here, we investigated the metabolite compositions of ripe fruits of both white (Morus alba) and black (Morus nigra) mulberries, using reversed-phase HPLC coupled to high resolution mass spectrometry (LC-MS), and related these to their in vitro antioxidant and α-glucosidase inhibitory activities. Based on accurate masses, fragmentation data, UV/Vis light absorbance spectra and retention times, 35 metabolites, mainly comprising phenolic compounds and amino sugar acids, were identified. While the antioxidant activity was highest in M. nigra, the α-glucosidase inhibitory activities were similar between species. Both bioactivities were mostly resistant to in vitro gastrointestinal digestion. To identify the bioactive compounds, we combined LC-MS with 96-well-format fractionation followed by testing the individual fractions for α-glucosidase inhibition, while compounds responsible for the antioxidant activity were identified using HPLC with an online antioxidant detection system. We thus determined iminosugars and phenolic compounds in both M. alba and M. nigra, and anthocyanins in M. nigra as being the key α-glucosidase inhibitors, while anthocyanins in M. nigra and both phenylpropanoids and flavonols in M. alba were identified as key antioxidants in their ripe berries.

中文翻译：

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桑树中生物活性植物化学物质的鉴定。

桑berries既可以新鲜食用，也可以作为加工后的水果食用，传统上用于治疗多种疾病，尤其是II型糖尿病。在这里，我们使用反相HPLC结合高分辨率质谱（LC-MS）研究了白桑（桑桑）和黑桑（桑桑）的成熟果实的代谢产物组成，并将其与体外抗氧化剂相关联和α-葡萄糖苷酶抑制活性。根据准确的质量，碎片数据，UV / Vis吸光度光谱和保留时间，鉴定出35种主要由酚类化合物和氨基糖酸组成的代谢物。虽然在黑僵菌中抗氧化活性最高，但物种间的α-葡萄糖苷酶抑制活性却相似。两种生物活性都对体外胃肠消化产生抗性。为了鉴定生物活性化合物，我们将LC-MS与96孔格式的分级分离相结合，然后测试各个组分对α-葡萄糖苷酶的抑制作用，同时使用在线抗氧化剂检测系统使用HPLC鉴定了负责抗氧化活性的化合物。因此，我们确定了白花念珠菌和黑花念珠菌中的亚氨基糖和酚类化合物，以及黑花念珠菌中的花青素是关键的α-葡萄糖苷酶抑制剂，而黑花念珠菌中的花青素以及白花念珠菌中的苯丙烷和黄酮醇被确定为成熟浆果中的关键抗氧化剂。而使用在线抗氧化剂检测系统的HPLC鉴定了负责抗氧化剂活性的化合物。因此，我们确定了白花念珠菌和黑花念珠菌中的亚氨基糖和酚类化合物，以及黑花念珠菌中的花青素是关键的α-葡萄糖苷酶抑制剂，而黑花念珠菌中的花青素以及白花念珠菌中的苯丙烷和黄酮醇被确定为成熟浆果中的关键抗氧化剂。而使用在线抗氧化剂检测系统的HPLC鉴定了负责抗氧化剂活性的化合物。因此，我们确定了白花念珠菌和黑花念珠菌中的亚氨基糖和酚类化合物，以及黑花念珠菌中的花青素是关键的α-葡萄糖苷酶抑制剂，而黑花念珠菌中的花青素以及白花念珠菌中的苯丙烷和黄酮醇被确定为成熟浆果中的关键抗氧化剂。