The phytochemical composition and antioxidant activity of fruits are associated with their health benefits. Longan is a traditional Chinese edible and medicinal fruit, but its varietal differences in phytochemical profiles and antioxidant activity were unknown. Twenty-four longan cultivars from southern China were investigated in this study. Their total phenolic and flavonoid contents in pulp were 22.09-132.47 mg gallic acid equivalents/100 g and 2.48-14.26 mg catechin equivalents/100 g, respectively. The mean contributions of free phenolics and flavonoids to the total were 82.5% and 94.0%, respectively. Among 10 individual phenolics detected by HPLC, the contents of epicatechin, 4-methylcatechol, chlorogenic, and vanillic acids were relatively higher. The cellular antioxidant activity (CAA) of longan pulp showed significant varietal discrepancies and positive correlation with phenolic and flavonoid contents. Phenolics in longan pulp of 24 cultivars showed lower CAA potential than many other fruits with the CAA qualities from 0.35 to 1.21 µmol quercetin equivalent/100 µmol total phenolics. Longan cultivars were classified into six groups by hierarchical clustering analysis. Six cultivars in group 4 and 6 had higher phytochemical contents and CAA activity. ARTICLE HISTORY

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Chlorogenic acid (CA), gallic acid (GA), and resveratrol (RES) were added to a gelatin (GEL)-chitosan (CHI)-glycerol (GLY) edible coating, and their effects on the coating of fresh beef preservation were investigated. The results revealed that CA had the most significant improvement effect on fresh beef preservation. The combination of GEL-CHI-GLY-CA preserved the color of the beef better and delayed the increase of the total volatile base nitrogen, even though its total phenolic content decreased at a faster rate during beef preservation. GA also improved the preservation effect as on the 12th day of storage, the beef samples treated with GEL-CHI-GLY-GA had the lowest thiobarbituric acid reactive substances (0.76 mg Malondialdehyde (MDA)/kg) and total viable count (6.0 log cfu/g). On the whole, though RES showed an improvement on beef preservation, the improvement was not as good as the other two polyphenols. After 12 days of storage, the beef samples treated with GEL-CHI-GLY-RES had a higher pH value (6.25) than the other two polyphenol treatmed groups. Overall, the three polyphenol-added combinations increased the shelf life of beef by approximately 3–6 days compared to the control group (treated GEL-CHI-GLY with distilled water).

This work develops an application of industrial sludge‐derived fuels (ISDF) that is based on the acceptable calorific value of pulp sludge and textile sludge. The optimal proportions of pulp sludge and textile sludge in ISDF are determined to produce the ISDF to obtain its optimal combustion efforts. Experimental results demonstrate that the calorific values of pulp sludge and textile sludge are 9.46 and 15.25 MJ kg−1, respectively, establishing the potential to be sludge‐derived fuels. Adding textile sludge increased the calorific value and flammability of ISDFs. The fibrous tissues in pulp sludge strengthened the cementing property of ISDFs. ISDFs regained 2.55–3.72% moisture after 72 h; their unit dry weight was 0.63–0.72 g cm−3; their compressive strength was 3.78–5.80 kgf cm−2; and their calorific value was 9.46–11.20 MJ kg−1. Adding 10% calcium hydroxide by weight reduced the calorific value of the ISDFs by 18.30–22.86%. The flame temperature of ISDFs in 5 min was 193.8–233.7°C. The optimal ISDF was PS70TS30. © 2013 American Institute of Chemical Engineers Environ Prog, 33: 1000–1007, 2014