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In order to prolong the shelf life of Chinese traditional dry-cured meat products, a pulsed ultraviolet light (PL-UV) irradiation method was adopted to treat meat products according to the following parameters: pulse energy of 8 J, 300 pulses, and an effective exposure distance of 10 cm; the UV light irradiation power of 6 W, an effective exposure distance of 11 cm, and an exposure period of 5 min. After a pulsed ultraviolet irradiation, total bacterial count in dry-cured meat decreased from 6.89 to 4.53 lg (CFU/g). The number of Micrococcus and Staphylococcus in samples decreased from 6.49 to 4.10 lg (CFU/g) and the number of molds and yeasts decreased from 5.45 to 4.28 lg (CFU/g). The number of Lactic acid bacteria increased from 3.97 to 4.55 lg (CFU/g) and Escherichia coli was not detected. Total colonies, target bacteria, peroxide value, thiobarbituric acid-reactive substances, water activity, T(2) relaxation time, pH, color difference, total volatile basic nitrogen, and the sensory evaluations of dry-cured meat products after PL-UV treatments were determined in a 30-d storage experiment. The shelf life of dry-cured meat treated with PL-UV irradiation at 20 °C was predicted to reach to 294 d by applying of shelf life testing method accelerated. The quality and safety of dry-cured meat treated with PL-UV irradiation was better than that of untreated samples.

Tripterygium wilfordii Hook. f. (TW) is a traditional herbal medicine which has been widely used for the treatment of rheumatoid arthritis and other autoimmune diseases. However, adverse reactions of TW such as hepatotoxicity and nephrotoxicity have been frequently reported in clinic. With the aim to evaluate the potency and toxicity of TW, we collected eleven batches of TW from different localities across Chinese mainland, and investigated the inhibition of their methanol extracts on the proliferation of mouse spleen lymphocytes, normal human hepatocyte (L-02) cells and African green monkey kidney (COS-7) cells. TW extracts with three different concentrations were designed as the experimental groups. Our present findings provided consistent evidence that TW had significant concentration-dependent inhibitory action on lymphocytes, L-02 and COS-7 cells. At the concentrations of 0.75 and 1.5 mg/mL, most TW groups showed statistically significant inhibition of lymphocyte proliferation when compared with the control group (p 0.01), and the inhibition of TW extract on lymphocytes was almost equal to 1.0 mg/mL aspirin (p 0.05). In most test groups, significant toxicities were shown on L-02 cells at 0.6 and 3.0 mg/mL (p 0.01), and on COS-7 cells at 3.0 mg/mL (p 0.01). At 3.0 mg/mL, almost all TW groups exerted obvious toxicities toward L-02 and COS-7 cells which were equal to or even higher than 1.0 mg/mL aspirin. In view of these results, further studies are needed to elucidate the relations among the effective component, curative effect and toxicity of TW to ensure its effectiveness and safety for human consumption.