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Copyright of Transactions of the Chinese Society of Agricultural Engineering is the property of Chinese Society of Agricultural Engineering and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Mulberry is rich in anthocyanins. The main component is cyanidin-3-O-glucoside. Anthocyanins are hydrophilic and water-soluble polyphenolic plant pigments and metabolites, which are one of the important antioxidants. They possess a wide range of pharmacological properties, such as anti-oxidant, anti-aging, anti-inflammatory, antimicrobial, and anti-cancer. Therefore, anthocyanins have great potential in various fields, such as the pharmaceutical and food industries. However, the relatively low stability of anthocyanin limits its bioavailability and effective applications, particularly on the degradation of anthocyanin. Taking the mature mulberry fruit as research objects, this study aims to prepare and characterize acylated mulberry anthocyanins using biological enzymes. The anthocyanin was extracted with acidified ethanol solvent and then purified by D101 macroporous resin. In order to reduce the degradation of anthocyanin while improving its stability, the mulberry anthocyanin was acylated by biological enzymatic and compared with that of non-acylated anthocyanin. Lipase, reaction solvent, and acyl donor were screened by single factor experiment to explore the anthocyanin acyl conversion rate. Taking the conversion rate as the evaluation index, the optimum conditions for acylation reaction were as follows: Candida Antarctica lipase as an acylating catalytic enzyme, pyridine as a catalytic reaction solvent, methyl benzoate as acyl donor, and the acylation effect was the best. The maximum conversion rate of mulberry anthocyanin was 13.5%. The products were analyzed by Fourier transform infrared spectroscopy (FTIR), Ultraviolet-visible spectrophotometer (UV-Vis), and high-performance liquid chromatography-mass spectrometry (HPLC-MS). Acylated anthocyanin was composed of C=O absorption peak at 1 650-1 870 cm-1, -OH bending vibration absorption, and C-O-C stretching vibration absorption of phenolic molecules at 1 000-1 300cm-1. There was also a skeleton vibration peak of the benzene ring (1 420-1 600 cm-1). The non-acylated anthocyanin sample had obvious UV absorption at 280 nm, and the absorption at this wavelength was the most stable. It showed that anthocyanin contained a benzene ring and a phenolic hydroxyl group on the benzene ring. The absorption peak of acylated anthocyanins moved forward from 280 nm to 271 nm, indicating that the structure of anthocyanins had changed. The mass charge ratios of acylated anthocyanin at 287, 449 and 595 (m/z), corresponding to the peaks of procyanidin, cyanidin-3-O-glucoside， and cyanidin-3-O-rutinoside, respectively. It was identified that the acylated products were monoacyl anthocyanin at 553 (m/z) or polyacyl anthocyanin at 657 (m/z). In addition, an attempt was made to explore the effects of acylation on the stability and antioxidant properties of anthocyanin. The acylation could improve the thermal stability, photostability, and acid-base resistance of anthocyanin. At the same temperature, the preservation rate of acylated anthocyanin increased by 5.0%, and it could be better preserved at 40, 50, and 60 . Light had a great influence on the stability of ℃ anthocyanin. The preservation rate of non-acylated anthocyanin decreased linearly to 77.3% within 10 days. After 6 days of light exposure, the preservation rate of acylated anthocyanin was still as high as 96.1%. At the pH values of 2, 3 and 8, the stability of acylated anthocyanin was improved. The acylation significantly increased the antioxidant activity of anthocyanin in vitro. DPPH radical scavenging activity was enhanced. The total reducing ability was 30% higher than that of the non-acylated anthocyanin. The chelating ability of metal ions was 90% higher. The inhibition rate of acylated anthocyanin on tumor cell activity was up to 81%, while that of non-acylated anthocyanin was only 50%. Therefore, acylated anthocyanin can effectively inhibit the proliferation of tumor cells. This finding can provide a theoretical basis and technical support for the stable application and performance improvement of anthocyanin in the production fields of functional food, biomedicine, botanical pesticides, and daily cosmetics fields. [ABSTRACT FROM AUTHOR]

Copyright of Shipin Kexue/ Food Science is the property of Food Science Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Most of the articles about the degradation performance of biodegradable nursery pots were focused on degradation morphology, strength of pot body, changes of soil, effect of raising seedings and so on. However, it rarely study on degradation rate, molecular structure of degradation process and changes of crystallinity. In order to study the degradation performance of biodegradable nursery pots, three types containing paper pot, undecomposed straw pot and decomposed straw pot were used to carry out the experiment in this paper. The degradation rate, molecular structure and crystallinity were evaluated and analyzed through the experiments of degradation test in soil, Fourier infrared scanning and x-ray diffraction. It is necessary to have a further research on degradation performance of biodegradable nursery containers and mechanism of degradation. The results showed that the degradation rate of paper pot with the best degradation property was growing at a rate of about 2 times. The maximum degradation rate was up to 85%. The undecomposed straw pot has always maintained a stable and increasing degradation rate. The undecomposed straw pot with degradation rate of 78% in the eighth week was higher than that of decomposed straw pot. The changes of mass loss and degradation rate were likely to be affect by a variety of microbial community structure. On the one hand, due to partial degradation of cellulose and semicellulose, the remaining part kept stable performance. On the other hand, the changes of microbial structure and activity affected the degradation performance. By comparison, FTIR absorption strength of the biodegradable nursery pots was decreased in different degree due to the changes of molecular structure during biodegradation. The absorption strength of paper pot decreased in the location of 3340 cm-1 and 2920 cm-1 indicated that the degradation of cellulose and hemicellulose. In addition, the relative peak of 1640 cm-1 and 1460 cm-1 decreased with the further degradation, showing that lignin was degraded in the biological reaction. The peak strength of CH stretch band was enhanced obviously at 892 cm-1. It showed that the substitution reaction of aromatic ring was an important part of the degradation process of lignin. The main group structure of undecomposed straw pot and decomposed straw pot were basically the same. The absorption peaks strength decreased at 3340 cm-1 and 1010 cm-1 might be due to the oxidative decomposition of benzene methanol unit. The peak strength of CH stretch band decreased at 2920 cm-1 probably because of the decomposition of carbohydrates and the fracture of partial fatty chain. The degradation of lignin resulted in the decrease of peak strength of 1650 cm-1. The x-ray diffraction peak intensity of paper pot with the best degradation property decreased obviously after 8 weeks test. The diffraction peak disappeared at 2 θ=15.6°. At the same time, The intensity of diffraction peak decreased at 2 θ=22.5°. In addition, it appeared new diffraction peaks at 2 θ=27° of undecomposed straw pot and decomposed straw pot. This might be due to the changes of crystalline which caused by the degradation of straw. The biodegradable nursery containers with excellent degradation property could improve the problem of environmental pollution effectively. [ABSTRACT FROM AUTHOR]