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关键词： 食品抽检   微生物   不合格   山东省  

摘要： 民以食为天,食品安全与人们的身体健康密切相关,而微生物是影响食品安全的主要因素之一,其也是国家食品安全标准中评价食品安全性的一项关键性指标。本文依据2019年山东省食品安全抽检公告信息,对微生物不合格食品的类别、具体微生物检验项目进行汇总统计,分析导致食品中微生物超标的可能因素,以期为政府加强食品安全监管、企业良好健康发展、群众安全消费食品提供一定的帮助。

关键词： 双万计划   食品化学   金课  

摘要： “双万计划”提出了要建设国家级和省级一流本科专业,而课程是人才培养的基础,一流的专业需要“金课”来支撑,具有高阶性、创新性和挑战度是“金课”的基本内涵,为了发掘学生的科学思维和创新潜能,在此背景下,对食品专业基础课食品化学进行了“金课”建设探索,主要包括授课内容优化、教学模式改革、教学团队建设和考核评价方式革新等。

关键词： Antioxidants   Metabolic enzymes   Seawater acidification   Litopenaeus vannamei  

摘要： Acidification in the marine environment has become a global issue that creates serious threats to marine organisms. In the present study, we evaluated the effect of CO2 driven acidification on the shrimp Litopenaeus vannamei post-larvae (PL). L. vannamei PL were exposed to six different CO(2 )driven acidified seawater, such as 8.2 (control), pH 7.8 (IPCC-predicted ocean pH by 2100), 7.6, 7.4, 7.2 and 7.0 with corresponding pCO(2) level of 380.66, 557.53, 878.55, 1355.48, 2129.46, and 3312.12 mu atm for seven weeks. At the end of the acidification experiment, results revealed that the survival, growth, feed index, biochemical constituents, chitin, minerals (Na, K, and Ca), and hemocyte populations of shrimps were found to be significantly decreased in CO2 driven acidified seawater which indicates the negative impacts of acidified seawater on these parameters in L. vannamei. Further, the level of antioxidants, lipid peroxidation, and metabolic enzymes were significantly higher in the muscle of shrimps exposed to acidified seawater suggests that the L. vannamei under oxidative stress and metabolic stress. Among the various acidified seawater tested, pH 7.6 to 7.0 produced a significantly adverse effect on shrimps. Hence, the present study concluded that the elevated level of seawater acidification can produce harmful effects on the biology and physiology of the commercially important shrimp L. vannamei PL.

摘要： VOLUME 295 (2020) PAGES 17852–17864

关键词： Paraechinus aethiopicus   Haematology   Biochemistry   Reference intervals   Saudi Arabia  

摘要： The Ethiopian hedgehog (Paraechinus aethiopicus) is an insectivore which is known to occur in northern an eastern Africa and in most of the Arabian Peninsula. Few recent studies on the reproduction, parasitology and ecology are available, but none has been published on the hematology and serum biochemistry reference intervals. Hence the present study was conducted in order to establish haematological and biochemical for free ranging apparently healthy hedgehogs using automated haematology and biochemistry analyzers. Variation and differences in blood values between males and females as well as before and after hibernation were evaluated. Blood samples from 50 males and 35 females were used for the establishment of the reference interval for the haematological and biochemical variables. Data from males and females were compared using student's t-test in the computer program SPSS. Significant sex-related haematological differences were observed in the total WBCs, monocytes, RBCs, MCV and MCH values. Males showed significantly higher WBCs compared to females whereas females showed significantly higher values form monocytes, RBCs, MCV and MCH than males (p < 0.05-0001). Changes in the biochemical profiles were significant in AlP, BUN and Na. ALP and BUN were higher in males while Na was higher in females (p < 0.05-0.01). The effect of hibernation was evidenced by increase in the RBCs, haemoglobin, haematocrit and MCHC and decrease in the total protein and phosphorus in animals after hibernation. These findings are considered the first regarding the reference intervals for the desert hedgehog and it will constitute a basis for any further haematological and biochemical studies. (C) 2020 The Authors. Published by Elsevier B.V. on behalf of King Saud University.

关键词： Zamzam water   Liver enzymes   Liver and kidney tissues   Kidney function   Hepatotoxicity   Nephrotoxicity  

摘要： Zamzam water is a natural alkaline water which has become alkaline as a result of the natural environment. It comes from what is considered as one of the oldest springs in the world. The water contains high concentrations of alkaline minerals as well as trace and heavy metals. The aim of the current study is to evaluate the effects of five weeks ingestion of Zamzam water on the liver and kidney functions of rats. Adult female Wistar rats weighing 150-200 g were divided into two groups, with 15 rats in each. The control group was supplied daily by bottled water and the Zamzam water group was supplied daily by 500 ml of Zamzam water for five weeks. The rats were weighed weekly and, at the end of the experiment, blood samples were collected from all rats for the biochemical determination of serum levels of aspartate transaminase (AST), alanine aminotransferase (ALT), alkaline phosphatase (ALP), urea, creatinine, albumin, and uric acid, using calorimetric methods. Liver and kidney tissues were fixed in 10% neutral buffered-formalin solution and further embedded in wax blocks for routine hematoxylin and eosin (H&E) staining and were examined for histopathological changes using a light microscope. The results of the current study showed that there was a significant increase (P < 0.05) in the weight of the Zamzam group when compared to the control group after five weeks of ingestion. Liver and kidney function tests did not show any significant difference when compared with the controls (P > 0.05). In addition, histological examination of the liver and kidney tissues did not show any toxicological changes. In conclusion, the results showed that the ingestion of Zamzam water did not alter serum levels of kidney function tests and liver enzymes;and did not result in a noticeable change in the liver and kidney histology. Thus, the high concentrations of elements in Zamzam water do not induce hepatotoxicity or nephrotoxicity and the water is considered safe for long-term consum

关键词： biosensor   biochemical oxygen demand (BOD5)   poly(vinyl alcohol)   N-vinylpyrrolidone   association of microorganism   immobilization in layer-by-layer films  

摘要： A new approach has been developed for the formation of the biosensor recognition elements via the immobilization of microorganisms in layer-by-layer films in order to determine the biochemical oxygen demand (BOD). Bioreceptor elements of BOD-biosensors have been fabricated based on the bacterial microorganisms Paracoccus yeei, Pseudomonas veronii, and Bacillus proteolyticus isolated from activated sludge. The recognition element was formed with via layer-by-layer deposition;each layer contained cells of one species. A similar multilayered recognition element based on yeast cells of Ogataea angusta, Blastobotrys adeninivorans, and Debaryomyces hansenii was created. In both cases, the cells were immobilized in a hydrogel of polyvinyl alcohol modified with N-vinylpyrrolidone. It was found that layer-by-layer immobilization increases the sensitivity of both the yeast- and bacterial cell-based biosensors. It was surmised that this is due to the lack of competition for substrate within the layer and its greater ability to each of the cell layers. The effects of the composition of the assayed samples (pH, ionic strength, heavy metal compounds) on the oxidative activity of the developed recognition elements have been studied. The analytical and metrological characteristics of the biosensors have been defined. The lower limit of the estimated BOD5 values was 0.5 mg O-2/dm(3) and 0.7 mg O-2/dm(3) for bacterial- and yeast cell-based biosensors, respectively. BOD5 was detected in water samples with the fabricated recognition elements. It was shown that the use of these two bioreceptors makes it possible to obtain data that strongly agree with those obtained with traditional method and that biosensing analyzers can act as prototype pilot model of the devices

关键词： Antioxidant enzymes   Autumn daffodil   Dormancy   Eradication   Heat map   Photoperiod  

摘要： Understanding bulb dormancy while examining temperature-related requirements and photoperiod are essential for successful commercialization and the greenhouse forcing of autumn daffodil (Sternbergia lutea). In this study, autumn daffodil bulbs were stored at 5, 15 and 25 degrees C for one month. Then, one group of bulbs were evaluated in terms of biochemical characteristics in three parts of each bulb (scale, central bud and basal plate). A second group of bulbs were planted in a greenhouse for a separate experiment to study the effects of different photoperiods (short, moderate and long) on morphological traits. The heat map of treatments in the first experiment revealed that the bulb storage temperatures of 15 degrees C and 25 degrees C had somewhat similar effects on all three parts of the bulb but, conversely, 5 degrees C had discrete effects. The 5 degrees C resulted in higher contents of proline in the scale, along with more H2O2 and malondialdehyde (MDA) in the basal plate. The highest activity of peroxidase (POD) and superoxide dismutase (SOD) were observed at 15 degrees C in the basal plate and at 5 degrees C in the central bud, respectively. In the second experiment, the time required for bulb sprouting and time to flowering were as follows: 5 degrees C>25 degrees C>15 degrees C. The heat map analysis indicated that temperature played a more substantial role than what photoperiod did in shaping the morphological traits. The interaction between 15 degrees C and the moderate photoperiod led to the highest value of most vegetative traits and of flowering percentage (70%). Therefore, this treatment can be considered as optimum for breaking relative bulb dormancy and to succeed better in growth and flowering.

关键词： Amphora   Broiler   Dietary supplement   Growth factor   Spirulina  

摘要： Spirulina platensis(Sp) orAmphora coffeaeformis(Am) are good candidates as an in-feed antibiotic substitute for broilers. This work was performed to investigate the effects ofSpandAmon the growth performance, intestinal microbial population, physiological responses, and blood biochemical constituents in broiler chickens. Fifty-one-day old Cobb broilers (with initial body weights 50-55 g) were allocated to five groups. Each treatment group had five replicate pens with two birds each. The experiments lasted for 35 days. The 1st group had basal diet (control group). The 2nd and 3rd groups received basal diet, along with 5- or 10-g/kgSpas a feed ingredient, respectively. While the 4th and 5th groups received basal diet, along with 5- or 10-g/kgAmas a feed ingredient, respectively. Data analysis revealed significantly higher body weight gains (P <= 0.05) with higherSporAmlevels and, in turn, linear improvements (P <= 0.05) in feed conversion values. In addition, intestinalLactobacillussp. was increased, andEscherichia colipopulations were decreased by both dietarySplevels orAmlevels. Furthermore, the liver (% body weight) was significantly decreased (P <= 0.05) and the heart (% body weight) was significantly increased (P <= 0.05) with higherSporAmlevels in comparison with untreated control. In conclusion, dietary inclusion with 10 g/kg ofSpandAmcould improve the growth performance, serum biochemical parameters and intestinal microbial population in broiler chickens.