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Indian jujubes are perishable fruits with a short storage life after harvest. In this study, Indian jujube fruits were stored at 5 °C and 90% RH for 30 days after treating the fruits with 1% chitosan (CHS), 1 mM putrescine (PUT), and a combination of 1% CHS and 1 mM PUT (CHS+ PUT). Physicochemical characteristics and cell wall degrading enzymes were measured at 10-day intervals. The results indicated that the efficiency of the CHS+PUT was better than CHS or PUT as individual treatments. The CHS+PUT treatment substantially decreased weight loss, decay incidence, and malondialdehyde content in Indian jujube fruits. The CHS+PUT treatment minimized losses of bioactive compounds (ascorbic acid and phenols), total antioxidant activity, and titratable acidity. In addition, CHS+PUT treatment delayed fruit softening by suppressing polygalacturonase activity and pectin methylesterase enzymes. Soluble solids content significantly increased through storage time, but applying CHS and PUT individually or in combination inhibited this increase. These results confirmed that the 1% CHS and 1 mM PUT treatments maintained the postharvest quality of Indian jujube fruits in cold storage. [ABSTRACT FROM AUTHOR]

A simple method based on miniaturized dispersive liquid-liquid extraction is reported for extraction and preconcentration of formaldehyde in water samples. Eight milliliters of an aqueous sample containing 2,4-dinitrophenylhydrazine were added to a 10.0 mL volumetic flask containing 1.0 mL of methanol-butyl acetate (2:1) mixture. After phase separation the analyte was determined by HPLC-UV. No clean-up or evaporation were required after extraction. Several factors influencing the extraction efficiency, such as the type and volume of organic solvent, type and volume of co-solvent, pH of the sample solution, ionic strength, and extraction time were evaluated and optimized. Under optimal experimental conditions, good linearity was obtained in the range of 1.5 x [10.sup.-4]-10 µg/mL (r = 0.996), and the limit of detection was 5 x [10.sup.-5] µg/mL. The method produced 20-fold enrichment of the formaldehyde. The average recovery of spiked formaldehyde in real samples was in the range of 90-110% with RSD in the range of 3-8%. Keywords: formaldehyde, high-performance liquid chromatography, fruit juice, streptococcus vaccines, low density miniaturized dispersive liquid-liquid extraction method DOI: 10.1134/S1061934815120096, Formaldehyde is an important chemical used widely by industry to manufacture building materials and numerous household products. Formaldehyde is commonly used as an industrial fungicide, germicide, disinfectant, and a preservative [...]