摘要：
Hyperglycemia, a diagnostic characteristic of diabetes mellitus, is detrimental to pancreatic beta cells. Delphinidin, a member of the anthocyanin family, inhibits glucose absorption, increases glucagon-like peptide-1 (GLP-1) secretion, and improves insulin secretion in diabetes. However, whether delphinidin plays a protective role in pancreatic beta-cell mass and function is not clear. In this study, delphinidin was found to decrease the high-glucose-induced apoptosis of RIN-m5F pancreatic beta cells. In addition, delphinidin induced autophagy in RIN-m5F cells under the normal and high-glucose conditions, while 3-methyladenine (3-MA) inhibition of autophagy significantly diminished the protective role of delphinidin against high-glucose-induced apoptosis of pancreatic beta cells. Delphinidin also decreased the level of cleaved caspase 3 and increased the phosphorylation level of AMP-activated protein kinase alpha (AMPKalpha) Thr172. Compound C, an AMPK inhibitor, was found to decrease the ratio of LC3-II/LC3-I, and the apoptotic rate of high-glucose-injured cells was increased after treatment with delphinidin, indicating that delphinidin attenuated the negative effects of high-glucose stress to cells. In conclusion, our data demonstrate that delphinidin protects pancreatic beta cells against high-glucose-induced injury by autophagy regulation via the AMPK signaling pathway. These findings might shed light on the underlying mechanisms of diabetes and help improve the prevention and therapy of this common disease.
摘要：
ABSTRACT Fermented-chopped pepper is a traditional-fermented vegetable in China. Chopped pepper is generally made with pepper, garlic, and ginger. In present study, the volatile compounds, obtained from chopped peppers during spontaneous fermentation, were analyzed by solid-phase microextraction (SPME) and gas chromatography-mass spectrometry (GC-MS). One hundred and forty volatile compounds were identified by solvent-assisted flavor evaporation, including 42 hydrocarbons, 34 esters, 16 alcohols, 21 aldehydes, 8 acids, 4 ketones, 4 ethers, and 9 other compounds. Alcohols, esters, and ketones were the dominant volatile fractions. The terpenes were found to be the main contributors to chopped pepper samples. It is important to note that among terpenes, such as β-phellandrene, α-curcumene, elemene, geraniol and nerolidol may originated from ginger. In addition, diallyl disulfide and diallyl sulfide, the two major sulfur components, may originated from garlic volatile oils. The results indicated that the ginger and garlic as raw materials played an important role in the flavor of chopped pepper. The contents of esters significantly increased during the fermentation process, the ethyl palmitate and ethyl linoleate were the main esters. The content of β-ionone as an degradation compound of carotenoids increased significantly with the fermentation period. Principal component analysis (PCA) was applied to discriminate the fermented-chopped peppers samples according to different times, and the fermented-chopped pepper samples were clearly differentiated on PCA plots. The fermentation stage was mainly affected by esters, alcohols, aldehydes and terpenes.
摘要：
As a new class of promising fluorescent carbon nanomaterials, carbon dots (CDs) have been well developed in recent years for their excellent fluorescent properties, simple synthetic approaches, good biocompatibility and various detection applications, which can be expected to replace the tradition semi-quantum dots. This review aims presents the current progress in the development of CDs with an emphasis on fluorescent properties, synthetic approaches and applications in food safety. First, the fluorescent properties of CDs are briefly introduced. To seek more reasonable synthetic approaches, the characteristics of the diverse methods of CD synthesis are summarized. And then, applications of CDs as fluorescent probes in food safety are discussed, with emphasis on the determination of metal ions/anions, pesticides, veterinary drugs, bacteria, functional components and banned additives. Finally, the challenges, such as how to explain the diversity of fluorescent properties, and how to form a uniform synthesis procedure to improve the quantum yield (QY), for CDs are presented. Although CDs have found many applications in food safety, it is still a challenge to detect a specific target in complex samples. Therefore, combination with other biochemistry technology to exploit novel ligands against the specific target with high binding affinity and selectivity is vitally important for developing sensitive and specific sensing probes in the future.
摘要：
Lotus seed is well known as traditional food and medicine, but its skin is usually discarded. Recent studies have shown that lotus seed skin contains a high concentration of proanthocyanidins that have multi-functions, such as antioxidation, anti-inflammation, and anti-cancer effects. In the present study, we aimed to isolate and purify the proanthocyanidins from lotus seed skin by acetone extraction and rotary evaporation, identify their chemical structures by HPLC-MS-MS and NMR, and further investigate the antioxidant properties of the extract purified by macroporous resin (PMR) from lotus seed skin both in vitro and in vivo. The results showed that PMR mainly contained oligomeric proanthocyanidins, especially dimeric procyanidin B1 (PB1), procyanidin B2 and procyanidin B4. Although it had limited ability to directly scavenge radicals in vitro, PMR could significantly enhance the expressions of antioxidant proteins via activation of nuclear factor-E2-related factor 2 (Nrf2)-antioxidant response element (ARE) pathway in HepG2 cells. Molecular data revealed that PB1, a major component in PMR, stabilized Nrf2 by inhibiting the ubiquitination of Nrf2, which led to subsequent activation of the Nrf2-ARE pathway, including the enhancements of Nrf2 nuclear translocation, Nrf2-ARE binding and ARE transcriptional activity. Moreover, the in vivo results in high fat diet-induced mice further verified the powerful antioxidant property of PMR. These results revealed that lotus seed skin is a promising resource for functional food development.
摘要：
雪里蕻（Brassica juncea var. multiceps）,俗称辣菜,为芥菜的变种,常腌制后调味加工食用。由于雪里蕻季节性强,一般采用盐渍的办法进行保存。采用理化、微固相萃取结合气质联用的方法,以新鲜原料为对照,测定了不同盐渍时间原料的酸度、盐度、水分、亚硝酸盐及挥发性成分,分析结果表明：不同盐渍时间原料的盐度在3.75%-15.27%之间,酸度在0.026%-0.488%之间,亚硝酸盐含量均较低,水分含量在66%-88%之间;挥发性成分检出差异性较大,最多的检测了65种,最少的12种。除新鲜样外，其余盐渍雪里蕻的共有挥发性物质主要有十六酸甲酯、十六酸乙酯、亚麻酸甲酯、亚麻酸乙酯、13-紫罗酮、乙酸、己酸，新鲜样中辛辣味很重，异硫氰酸酯类经腌制后含量大幅下降，使风味更加柔和，该结果对雪里蕻产品的标准化生产控制提供参考。
