| China's apple production ranks the first in the world. However, in recent years, our export of the concentrated apple juice has been restricted mainly because the amount of Patulin in the juice exceeds the standard. Therefore, it is rather important to improve the detecting ability and to control effectively the amount of Patulin in the juice as well. As the main producing strain in the production of concentrated apple juice, Penicillium expansum affects the quality of concentrated apple juice directly.The phenolic substances in the apple are generally called Apple Polyphenols, which is the latest potent antioxidant and one of the most powerful free radical scavengers that have been found. Owing to the high thermal stability, within the pH2-10 at 120℃it can still be alive and absorbed quickly and completely. So that it can reach the maximum blood concentration 20 minutes after taken orally with the help of the 7-hour half-life of metabolism. Experimental results show that many of its physiological activity are 100 times higher than the tea polyphenols. The main functions are to prevent tooth decay, to depress bad breath components in saliva production (4 mercaptan), to inhibit the volatile of fish odor (34 amine); to decrease the production of melanin, to restrain tyrosinase function; to reduce the ACE activity, to reduce blood pressure placidly, to relieve hypersensitivity, and to prevent cardiovascular disease, etc.The study starts from the detection of Patulin in the concentrated apple juice, conducts a thorough research of the recent detecting method. After the systematical research of the production and degradation of Patulin, and the systematical analysis of the antitumor effect of the Apple Polyphenols, major findings are as follows:(1) To detect the amount of the Patulin in the concentrated apple juice, High Performance Liquid Chromatography (HPLC) is operational, accurate and reliable, with the recovery rate as high as 98% to 103%, and the results are of high precision, good reproducibility, and high sensitivity, with the RSD < 1.8%. For 5mL of concentrated apple juice, the detection limit was 10μg/L, which can be taken as an accurate quantitative method for the apple juice producer.(2) In both batchs of static and shaking cultivations, patulin content increased firstly and then decreased. A clear second increase of cell growth appeared in the static cultivation, but not in the shaking cultivation. In total, residue sugar and pH kept decreasing and total titrable acids kept increasing through the whole cultivation in both static and shaking cultivations. During the cultivation, sugar was consumed for the cell growth and sythesis of patulin. Some kinds of acidic substance were produced in the cell growth and patulin sythesis.(3) In the batch of static cultivation, the period for the highest patulin production was consistent with the first high stable period for cell growth, in which spores of the P. Expansum started to form. Patulin reduced quickly from when the second quick cell growth happened in the static cultivation and in the middle period of the stable cell growth in the shaking cultivation. Patulin reduction also happened at the later cultivation stage when cells appeared decrease. Compared with the static cultivation, the dried cell weight was about 2 times more than, but the patulin production was 1/2 lower than, that in the static cultivation. This indicated conditions for patulin production might be consistent with that for spore formation. Abundant oxygen would be good for the cell growth of P. expansum, but not for the patulin production.(4) It is founded that lactic acid bacteria can absorb the growth of Aspergillus toxins by adding different doses of lactic acid during the growth of patulin, the growth of patulin can be controlled in the early fermentation. The results showed that it can play a better inhibition by addition of 500mg/L of lactic acid bacteria on the growth of Aspergillus clavatus toxins, at the same time, it is not impact the quality of concentrated apple juice products.(5) There is tumor-inhibitory effect in vivo of apple polephenols to H22, but no dose-dependent relation in the groups of H22. There is no influence on the survival periods by apple polephenols to EAC-receiving mice. There is no influence on the immunological function in tumor-receiving mice treated with apple polephenols.(6) There is the direct kill function in vitro of apple polephenols to H22, HT29 lump, and the dose-dependent relation in the groups of H22, HT29 lump. The results showed that Apple polyphenols can inhibit the H22 cell proliferation. Through inhibiting cell DNA synthesis, reduces the S phase percentage in the mitotic cycle, induce G2/M phase arrest, plays the antitumoral effect through the reduced fission time cell.
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