Ultrasonic assisted extraction of polyphenols from bayberry by deep eutectic supramolecular polymer and its application in bio-active film

Ultrasound and deep eutectic supramolecular polymers (DESP) is a novel combination of green extraction method for phytochemicals. In this study, a new type of green extractant was developed: DESP. It is a derivative of deep eutectic solvent (DES) and was prepared by supramolecular polymer unit β-cyclodextrin (β-CD) as hydrogen bond acceptor (HBA) and organic acid as hydrogen bond donor (HBD). The current work focuses on the use of ultrasonic-assisted (UAE) DESP extraction of polyphenolic compounds (PCs) from bayberry. The experimental results showed that DESP synthesized with β-CD and lactic acid (LA) in a ratio of 1:1 (w/w %) had the best extraction effect. And by using a three-level factor experiment and the response surface method, the predicted TPC content is very close to the actual content (28.85 ± 1.27 mg GAE/g). The DESP extract including PCs were further used as plasticizer for chitosan (CS) to prepare highly active green biofilms (DESP-CS). It is possible to reduce the tedious procedures for separating biologically active substances from DESP. The experiment proved that the prepared films have good mechanical properties, plastic deformation resistance, thermal stability and antioxidant activity.     

杨梅缺硼症状与硼肥施用技术研究

为矫治杨梅缺硼症状，采用了喷施和土施硼肥技术。调查和试验结果表明，杨梅硼元素缺乏的典型生理症状为叶小、枝梢丛生、枯梢、花量少，且不结果或很少结果。喷施0，2％硼砂液或0．2％硼砂 0．5％尿素液能明显矫治杨梅缺硼症状，改善春、夏两梢生长指标，提高坐果率，从而提高单株产量。土施硼肥也能取得较好的矫治效果，施用量以硼砂100g／株为佳；同时，土施处理在生产实际中还表现出良好的后续效应。     

Analysis of Proanthocyanidins in Plant Materials Using Hydrophilic Interaction HPLC-QTOF-MS

Proanthocyanidins (PACs) have been proven to possess a wide range of biological activities, but complex structures limit their study of structure–function relationships. Therefore, an efficient and general method using hydrophilic interaction high-performance liquid chromatography coupled with high-resolution quadrupole time-of-flight tandem mass spectrometry (HILIC-QTOF-MS) was established to analyze PACs from different plant materials. This method was successfully applied to characterize PACs from Chinese bayberry (Myrica rubra Sieb. et Zucc.) leaves (BLPs), sorghum testa (STPs) and grape seeds (GSPs). BLPs with the degree of polymerization (DP) from 1 to 8 were separated. BLPs are mainly B-type prodelphinidins and A-type BLPs were first found in this study. STPs and GSPs belonging to procyanidins showed DP from 3 to 11 and 2 to 12, respectively. A-type linkages were found for every DP of STPs and GSPs, which were first found. These results showed that HILIC-QTOF-MS can be successfully applied for analyzing PACs from different plant materials, which is necessary for the prediction of their potential health benefits.     

基于通过型固相萃取-超高效液相色谱-高分辨质谱同时测定杨梅中29种农药残留

建立了基于PRiME HLB通过型固相萃取净化-超高效液相色谱-高分辨质谱法(UPLC-HRMS)快速准确测定杨梅中29种常见农药残留的检测方法.杨梅样品经乙腈涡旋提取、盐析和PRiME HLB固相萃取净化后,以5mmol/L乙酸铵水溶液和乙腈溶液作为流动相在Waters ACQUITY UPLC HSS T3色谱柱(...