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Hui-juan Zhou, Xia-nan Zhang, Ming-shen Su, Ji-hong Du, Xiong-wei Li, and Zheng-wen Ye

quality ( Minas et al., 2018 ). Ultraviolet-C hormesis consists of the use of low doses of shortwave ultraviolet radiation with the objective of promoting desirable responses in living organisms ( Stevens et al., 2005 ), which could reduce the use of

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Ruixiang Yan, Joshua B. Gurtler, James P. Mattheis, and Xuetong Fan

. Ultraviolet-C radiation at short wavelengths (100–280 nm) has germicidal effects, resulting in damage to DNA ( Sinha and Häder, 2002 ). The U.S. Food and Drug Administration (FDA) has approved the use of ultraviolet light for disinfection of liquid (water and

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Junfang Wang, Yuxia Sun, Hengzhen Wang, Xueqiang Guan, and Lijun Wang

. Fig. 1. Schematic diagram of ultraviolet-C irradiation. Resveratol determination. According to the method of Liu et al. (2013) , each sample was extracted for 24 h in methanol and ethyl acetate (1/1, v/v; 1000 mg per 10 mL of organic solvent) (Beijing

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J. Liu, C. Stevens, V.A. Khan, J.Y. Lu, C.L. Wilson, O. Adeyeye, M.K. Kabwe, L. Pusey, E. Chalutz, T. Sultana, and S. Droby

The application of low hormetic low-dose ultraviolet light (WV-C, 254 nm) on fruits and vegetables to stimulate beneficial responses is a new method for controlling storage rots and extending the shelf-life of fruits and vegetables. The present study was aimed at treating tomatoes (lycopersicon esculentum) with different UV-C dosages (1.3 to 40 KJ/m2) to induce resistance to black mold (Alternaria alternata), gray mold (Boytris cinerea), and Rhizopus soft rot (Rhizopus stolonifer). Thesediseases were effectively reduced when tomatoes were artificially inoculated following UV-C irradiation UV-C treated tomatoes were firmer in texture and less red in color than the control tomatoes, indicating a delay in ripening. Slower ripening and resistsace to storage rots of tomatoes are probably related. The positive effect of UVC on tomatoes decreased as treatments were performed at stages of increased ripeness.

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C. Stevens, P. L. Pusey, V. A. Khan, J. Y. Lu, C. L. Wilson, E. Chalutz, M. K. Kabwe, Z. Haung, O. Adeyeye, and J. Lin

Low hormetic doses of ultraviolet light (UV-C) stress on exposed peaches (Prunus persica). reduced brown rot resulting from field and artificial inoculation from Monilinia fructicola. To test the hypothesis that UV-C induced resistance through host responses the following tests involving biochemical changes (phenlyalanine ammonia-lyase activity (PAL) and ethylene production (EP)), bioassay of antifungal activity of tissue extracts to the fungus, and latent infection of rot free peaches previously treated with and without UV-C were determined. Exposure of peaches to UV-C dose of 7.5×104 ergs/mm2 promoted an increase in PAL and EP compared to the control. As the PAL activity increased, percent storage rots decreased. Antifungal activity to the fungal conidia in UV-C treated peach extract showed that the percent conidia germination was reduced 3 folds. Preharvest infection of brown rot which indicated latent infection was significantly reduced. To test for the germicidal effect of UV-C on M. fructicola on the surface of peaches, an artificial epiphytic population of the fungus was deposited on the peaches. A negative relationship between UV-C dose of 1.3 to 40×104 ergs /mm2, colony forming units and number of decaying brown rot lesions were found.

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Guy D'hallewin, Mario Schirra, Enzo Manueddu, Antonio Piga, and Shimshon Ben-Yehoshua

1 Permanent address: C.N.R. Istituto per la Fisiologia della Maturazione e della Conservazione del Frutto delle Specie Arboree Mediterranee, Località Palloni, Nuraxinieddu 09170 Oristano, Italy. This work was supported in part by the National

Open access

Ittetsu Yamaga and Sakura Hamasaki

dark at 20 °C. Flavonoids were extracted at 1 d after ultraviolet irradiation, considering results of Expt. 1. Table 1. Average weight of a fruit used for experiments. Ultraviolet irradiation. UV-C irradiation was performed using two lamps (GL-15

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Edward J. Nangle, David S. Gardner, James D. Metzger, Dominic P. Petrella, Tom K. Danneberger, Luis Rodriguez-Saona, and John L. Cisar

exposure to wavelengths in the ultraviolet (UV-A 400–320 nm/UV-B 320–290 nm/UV-C 290–100 nm) range ( Kerr and McElroy, 1993 ). The UV-B wavelengths that contact the earth’s surface are predicted to increase in springtime radiation by 50% to 60% from 2010 to

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Yu-Wei Liu and Chen-Kang Huang

) ( Fig. 1B ), and a 60-W submersible pump (HP-3500; Ming-Zen Corp., Taichung, Taiwan) ( Fig. 1C ). A 15-W ultraviolet sterilization system developed by ISTA Corporation (Tainan, Taiwan) was also used and tested. During the experiment, full-strength Enshi

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Larry E. Schrader

detached raspberries at 42 °C or higher in the laboratory and needed 4 or more hours of ultraviolet radiation to induce sunburn. Yuri et al. (2000) concluded that temperature had more effect than did ultraviolet radiation on the appearance of sunscald on