EFFECT OF OXYTETRACYCLINE AND CHLORTETRACYCLINE ON SURVIVAL OF THE TREMATODE Heterophyes sp. IN THE FLESH OF MULLET CAUGHT IN BRACKISH EGYPTIAN WATERS

SUMMARY– Mullet, Mugil cephalus, caught from brackish Egyptian waters, serve as an intermediate host for Heterophyes parasite which renders such fish hazardous to health. The objective of this work was to show the effectiveness of antibiotics, used to prolong the storage life of fresh fish, as parasiticides. To achieve this, both whole mullet and small portions of infected mullet tissue were dipped in oxytetracycline (OTC) and chlortetracycline (CTC) solutions of different concentrations ranging from 30–4000 ppm. The rate of parasite destruction, very slow at low concentrations of either antibiotic, increased at much higher concentrations of antibiotic. However, a concentration of antibiotic sufficiently high to destroy the parasite completely cannot be used for the preservation of fresh fish because of the high concentration of antibiotic in the fish tissue after treatment. Although these findings are negative, they have a place in the literature.     

COMBINED EFFECTS OF ELECTRICAL STIMULATION AND METHODS OF MEAT PRESERVATION UPON THE SURVIVAL OF BACTERIA1

The synergistic effect caused by electrical stimulation and methods of meat processing on microbial numbers in meat was investigated. Electrical stimulation in all experiments reduced initial bacterial numbers and lowered tissue pH. Under the conditions of this research, no synergistic effect could be proven for electrical stimulation and 3% salt or 3% salt and 200 ppm of nitrite or for storage at -21°C. However, a synergistic effect was observed for electrical stimulation and heating at 60°C. This reduction in thermoresistance caused by electrical stimulation did not appear to be caused by the lowering of pH of the heating media.     

EFFECT OF MONOVALENT AND DIVALENT IONS UPON THE GERMINATION OF BACILLUS SPORES IN THE PRESENCE OF NISIN

SUMMARY— The effect of a monovalant ion like Na and divalent ions like Cu, Fe, Mn, Mg and Ca on the germination of spores of Bacillus stearothermophilus, B. cereus and B. megatherium both in the presence and absence of nisin was investigated. In the absence of nisin, Cu, Fe and Mn ions were more inhibitory than Ca and Na ions for the germination of all three kinds of spores. At 1M, Mg increased germination of different spores 3–9%. In the presencences nisin, both Ca and Mg increased the germination of B. stearothermophilus by 10.8 and 14.2%, of B. cereus by 30.4 and 19.9%, and B. megatherium by 6.6 and 30.9%, respectively. The rest of the ions increased inhibition of germination by nisin. The increase in germination by Ca and Mg was correlated with the release of DPA and is discussed.     

不同加工方法对山茱萸酒香气成分的影响

为研究不同加工方法对山茱萸酒香气成分的影响,分别采用浸泡和发酵法制备了山茱萸酒,采用GC-MS分析不同酒的香气成分,研究表明:浸泡法和发酵法制备的酒中,分别检出26和47种香气成分,酯类化合物的相对峰面积分别为1.63%和2.35%;醛酮类的化合物的相对峰面积分别为25.72%和3.13%.羧酸类和醇类的化合物的相对峰面积分别为52.73%和44.43%;杂环类化合物的相对峰面积分别为3.58%和46.93%,不同方法所得到的山茱萸酒,香气成分不同,发酵法制备的山茱萸酒,香气成分的种类多于浸泡法.     

莲房原花青素对免疫功能的影响

探讨莲房原花青素（procyanidins of lotus seedpod，简称LSPCs）对机体免疫功能的影响。采用小鼠碳廓清单核巨噬细胞吞噬功能测定法、迟发型超敏反应及血清溶血素测定方法、MTT法检测T、B淋巴细胞增殖、乳酸脱氢酶法检测NK细胞活性等，研究LSPCs对小鼠免疫功能的影响。结果：LSPCs能显著增强巨噬细胞的吞噬功能、对二硝基氟苯（DNFB）所致迟发型超敏反应以及抗体生成的能力；能刺激T、B淋巴细胞增殖、提高NK细胞活性。结论：LSPCs能有效地增强机体免疫功能。     

杜梨叶片多糖提取方法的研究

分别采用微波、水浴及超声波3种方法提取杜梨叶片多糖,用蒽酮-硫酸比色法测定多糖的含量.结果表明3种提取方法存在明显的差异,以超声波法提取效果最佳,其后依次是水浴及微波,3种方法提取多糖的含量分别是20.01%、10.41%和9.37%.     

METHODS FOR THE DETECTION OF FOODBORNE LISTERIA MONOCYTOGENES IN THE U.S.

A review of methods for the isolation and detection of Listeria monocytogenes used in the United States is presented. Methods reviewed include the cold enrichment technique, the FDA Method, the USDA Method, and two rapid techniques, the Listeria-Tek enzyme-linked immunosorbent assay and the Gene-Trak Listeria Assay. Comparisons of new rapid biochemical test kits, the MICRO-ID LISTERIA System, API Listeria, and the Rosco system vs. conventional tests of identification are also reviewed. Contemporary isolation methods detect all Listeria species so confirmation of L. monocytogenes is still necessary after isolation. The USDA method is the most practical of the cultural methods due to the rapid reporting of negative samples. Rapid methods (Listeria-Tek and the Gene-Trak Listeria Assay) are faster and more objective than cultural procedures but still depend on sample enrichment for detection of Listeria. These rapid techniques are best utilized when screening large numbers of food samples. All the rapid biochemical test kits reviewed provide fast reliable identification of Listeria species when compared to classical techniques. However, the API Listeria system identifies the test strains without a complementary CAMP test. Refinements are still needed in both cultural and rapid methods. Future Listeria methodology must emphasize molecular techniques not requiring enrichment which would be both rapid and specific for L. monocytogenes.     

竹黄菌丝体水溶性多糖提取工艺

采用热水浸提法对竹黄菌丝体多糖的提取工艺条件进行优化,以多糖得率为评价指标,选用单因素试验和L9(34)正交试验法,考察浸提温度、浸提时间、料水比、浸提次数、醇沉倍数等5个因素时竹黄菌丝体多糖得率的影响.结果表明提取竹黄菌丝体多糖的最佳工艺条件是:浸提温度100℃、浸提时间2 h、料水比1:80、提取3次、3倍乙醇沉淀,此条件下多糖得率可达到15.69%.     

丁香提取物对三种果实致腐真菌的抑制作用研究

以丁香等为试材,测定其对3种常见水果致腐真菌的抑制活性.结果表明,丁香乙醇提取物对桔青霉菌、葡萄灰霉菌、苹果褐腐菌均有很好的抑制作用,其抑菌能力在100℃下比较稳定,适宜pH范围较广.     

EFFECT OF DIFFERENT TREATMENT PROCESSES AND PRESERVATION METHODS ON THE QUALITY OF TRUFFLES: I. CONVENTIONAL METHODS (DRYING/FREEZING)

Truffles are one of the major food ingredients of many favorite traditional dishes in the Middle East. Because of their short shelf life, truffles are considered a perishable commodity. Two varieties of local truffles were blanched in 2 or 4% boiling salt (NaCl) solutions for 2 or 4 min or by dry salting and or spraying with 5% vinegar. The treated samples were dried in an oven at 110C or were immediately frozen at ?18C and were stored for 1 year. In conclusion, color, texture and flavor were best preserved by blanching in 4% boiling NaCl solution for 4 min. Freezing was superior to dehydration as a preservation method.     

NUTRITIONAL AND TOXICOLOGICAL EVALUATION OF SINGLE-CELL PROTEIN PRODUCED FROM BACILLUS SP. KISRI-TM1A IN RATS

Single-cell protein (SCP) produced from a novel thermotolerant methylotrophic Bacillus sp. KISRI-TM IA was fed to groups of 10 male and 10 female Wistar rats at levels of 0, 10, 20, and 30 percent of total diets. The feeding of KISRI-TM IA did not adversely affect growth, feed intake or hematological values of rats. Water intake of male rats decreased with increasing level of SCP in the diet. Urinary pH showed dose-dependent reductions in both sexes. Plasma alkaline phosphatase and alanine aminotransferase were significantly (P<.05) reduced by increasing levels of dietary SCP. However, no significant (p>.05) abnormalities were observed in the weights or histopathological appearances of the organs. It was concluded that the KISRI-TM 1A SCP could serve as a potential dietary ingredient at levels of up to 30% for poultry, young lambs and calves.     

热风式干燥对甘薯膳食纤维中抗性淀粉含量的影响

研究低温预风干后高温快速风干处理对甘薯膳食纤维中抗性淀粉含量的影响.低温预风干温度对甘薯膳食纤维中抗性淀粉含量的影响效果显著,而高温快速风干的温度和时间对抗性淀粉含量的影响效果不显著.低温预风干温度和抗性淀粉含量间的变化呈非线性关系.提高抗性淀粉含量的最佳工艺参数为:30℃低温预风干60h,再在60℃高温快速风干1 h,抗性淀粉含量可达11.26%.