Distribution of hydrophilic and lipophilic antibacterial drugs in skim milk,cream, and casein

This study determined the distribution of drugs to different milk fractions according to their physicochemical properties. Hydrophilic drugs tend to concentrate in skim milk, whereas lipophilic drugs tend to concentrate in cream. The concentration of a drug in casein is related to its degree of binding to milk proteins. Thus, we aimed to determine whether withdrawal time in whole milk differs from that in cream, casein, and skim milk. Amoxicillin and tylosin were selected as prototype hydrophilic and lipophilic drugs, respectively. The study was conducted in vitro and in vivo to determine whether in vitro conditions reflect the distribution of drugs in the different milk fractions in vivo. The in vivo study was conducted using a crossover design on 6 healthy Holstein dairy cattle. First, amoxicillin (i.m., single dose, 14 mg/kg) was administered to cows. Following a 1-wk washout period, tylosin (i.m., single dose, 15 mg/kg) was administered. Concentrations of amoxicillin and tylosin in milk and milk fractions were measured using HPLC-UV. In the in vitro study, 0.04 to 400 μg/g of amoxicillin and 0.05 to 50 μg/g of tylosin were spiked to drug-free milk and the concentrations in milk and milk fractions were measured. In addition, the percentage of total protein in milk and milk fractions was determined. Amoxicillin accumulated more in skim milk than in cream and casein, both in vitro (92%) and in vivo (73%, skim milk-to-whole milk ratio). The distribution of tylosin in whole and skim milk was similar to that of amoxicillin in the in vitro study, in contrast to the accumulation of tylosin in cream seen in vivo. However, the accumulation ratio of tylosin in cream was lower than expected. By either method, tylosin was less concentrated in casein than in skim milk and cream. The percentage of total protein was similar in skim milk and whole milk and higher than in cream. Thus, amoxicillin accumulates less in cream and casein, suggesting that these fractions would pose a lower risk to the consumer. Tylosin was still present at the maximum residue limit (50 μg/kg) 24 h after injection in the casein fraction and 48 h after injection in the cream fraction.     

Quercetin alleviates activities of intestinal and renal disaccharidases in streptozotocin-induced diabetic rats

Specific activities of both intestinal and renal dissacharidases, such as sucrase, maltase, and lactase, were altered in diabetic rats. Our study was focused to evaluate the effect of feeding quercetin - a bioflavanoid on intestinal and renal dissacharidases in streptozotocin-induced diabetic rats. The rats were fed with 0.1% quercetin in diet. A reduction in intestinal maltase and sucrase, activities in quercetin-fed diabetic rats was observed in contrast to the increased activities in the starch-fed diabetic rats. A significant amelioration in renal dissacharidase activities in quercetin-fed diabetic rats was observed when compared to decreased activity in starch-fed diabetic rats.     

Changes in meat quality characteristics of bovine meat during the first 6 days post mortem

The development of some quality parameters in bovine meat during the first 6 days of post mortem ageing was studied in two commercial groups (heifer and bull). In the first day bull meat is harder and springier. Meat pH falls during the first 24 h post mortem in both groups, reaching values around 5.5, and it did not change during the next 5 days. Water-holding capacity (expressed as percentage of expelled water) increased in heifer meat. Instrumental texture measures (texture profile analysis, TPA) showed a decrease in hardness, springiness and chewiness in bull raw meat. Sensory analysis showed that assessors perceived a decrease in hardness and in springiness in bull meat and a decrease in juiciness and in chewiness (number of chewings before swallowing) in heifer meat. Ageing showed no effect on assessors’ pleasantness either in heifers’ or in bulls’ meat. During the first 3 days, heifer meat was juicier. Heifers’ meat produced a greater pleasantness on the sixth day. Both meats were not very different for most quality parameters studied in this work.     

广州秋季市售生蚝微生物污染状况调查

目的是了解广州秋季市售生蚝微生物污染状况。按照GB／T4789—2003《食品卫生微生物学检验》对样品进行微生物检测,结果发现秋季市售生蚝的微生物污染状况比较严重,菌落总数和大肠菌群指标均出现严重超标,超标率分别达到68％和78％,即使在温度偏低的11月份超标现象仍较严重。所检样品中,弧菌超标更为严重,3个月弧菌的检出率则高达90％。结论是广州市售生蚝的微生物污染状况严重,建议消费者不要生食或使用未煮熟的生蚝。     

Trace mineral content of conventional,organic and courtyard eggs analysed by inductively coupled plasma mass spectrometry (ICP-MS)

We investigated the contents in yolk and albumen of the trace minerals Se, Zn, Mn, Co, Cu, Mo, V, Cr, Ni, Tl, As and Cd in eggs from hens from three husbandry systems by ICP-MS. Conventional hens were given a commercial feed with added minerals, organic hens were given a feed based on organic feedstuffs also with added minerals, and courtyard hens were fed on cereals, legumes, grass and swill. Dietary Se, Zn, Mn, Co and Cu concentrations were lower in courtyard compared to conventional and organic diets; Cr concentration was highest in courtyard compared to organic diet. Trace element contents in yolks were higher than those in albumen. The highest content of Se in yolks was in organic, followed by conventional eggs. Zn contents were highest in courtyard yolk, followed by conventional, which in turn was higher than organic. Mn yolk contents were lowest in courtyard eggs; Cr contents were highest in courtyard eggs. The differences in albumen were in Zn and Cr values, which were highest in courtyard eggs. Τhe results provide baseline measurements of trace mineral contents of eggs and suggest measurable differences amongst eggs from hens in different husbandry systems; the physiological significance of these differences are discussed.     

恩施州植烟土壤及烟叶硒含量状况分析

调查了恩施州植烟土壤及烟叶硒含量状况。结果表明:(1)恩施州植烟土壤硒含量平均为0.661 mg/kg,从土壤总硒水平来看,恩施土壤属于富硒土壤。烟叶硒含量平均为0.216 mg/kg,并表现为B2F>C3F>X2F,高于我国其他烟区。(2)恩施土壤硒的垂直地理分布特性明显,即随海拔高度的升高而极显著地增加;土壤硒含量与土壤中有机质、碱解氮、速效磷、速效钾等大量元素具有极显著正相关,而与pH的相关性没有达到显著水平。当土壤等级为足硒和富硒土壤时,土壤中主要养分含量处于烟叶生长所需的适宜范围内。(3)在相对较高的硒含量土壤中,烟叶对硒的吸收累积强于低硒土壤。8个植烟县(市)土壤和烟叶硒含量的相关性均为正相关。     

Varietal differences in the mineral composition of bulked samples of fruit from Cox's Orange Pippin,Crispin (Mutsu) and Spartan apple trees

Concentrations of dry matter, nitrogen and major mineral constituents in samples of Cox's Orange Pippin and Crispin fruit from interplanted trees were measured for 4 years. Similar measurements were made over a 6 year period in Cox and Spartan fruit samples from trees interplanted in another orchard. Concentrations varied greatly in all varieties from year to year. In comparison with Cox, fruit calcium concentrations were higher for a given mean mass per apple in Crispin in all years and in Spartan for 4 of the 6 years at harvest. Concentrations of nitrogen, potassium, magnesium and phosphorus were lower in Crispin and Spartan than in Cox fruit at harvest in all years, but dry matter and sodium concentrations differed only in some years. Changes in concentrations during fruit growth were measured in 2 years for each comparison. Differences between nitrogen, phosphorus and potassium concentrations in either Crispin or Spartan and Cox apples were evident throughout fruitlet enlargement in both years. Calcium concentrations were higher in Crispin and Spartan fruitlets than in Cox fruitlets of equivalent mass. Variations in the concentrations of potassium, magnesium and calcium from tree to tree were greater for Cox than Crispin samples but relationships between potassium and magnesium concentrations were similar for both varieties.     

气候变化背景下鄂西烟草种植气象风险评价与区划

为了确定湖北西部植烟区的气象灾害风险程度,根据灾害学系统理论,从致灾因子、孕灾环境、承灾体和防灾减灾能力4个子系统出发,综合考虑气候条件、地理地形、社会经济状况等多个因素,利用GIS平台对鄂西烟草种植气象灾害风险进行评价与区划。结果表明,鄂西北地区气象灾害危险性东高西低,南北向无明显规律,而鄂西南地区是南高北低;鄂西南巴东和恩施烟草易损性较小,而鄂西北的枣阳和丹江口市易损性较大;鄂西南北部地区的气象风险低于南部地区,而鄂西北南部地区气象风险较小,东部气象风险最大;神农架局部地区和鹤峰、丹江口市东部等地的气象风险最严重。总体而言,鄂西地区适宜种植烟草,尽管存在风险,但是大部分地区风险等级在中等及中等以下,这对指导当地合理规划烟草种植和生产具有重要意义。     

Biochemical changes during ripening of some sudanese date varieties

Changes in the chemical composition of three popular Sudanese varieties of date (Jawa, Bentamoda and Mishrig Wad Laggai) during ripening are described and are related to changes in texture and in the activities of various degradative enzymes in the fruit. Total invertase levels were high throughout maturation of the three varieties. Although the proportion of soluble enzyme increased during ripening solubilisation did not appear to influence the relative amounts of sucrose and reducing sugars in the ripening fruit. Both cellulase and polygalacturonase were absent or at low levels in the green fruit but displayed large increases in activity during ripening. This enhancement was reflected in a reduction in fruit firmness although little change in cellulose or pectin levels was apparent analytically until the final stage of ripening. Despite a considerable rise in pectinesterase activity during ripening no significant trend could be discerned in the degree of esterification of pectin suggesting that the enzyme is of minor importance in softening of these fruit.     

Analysis of plasticizers in cap-sealing resins for bottled foods

A survey of plasticizers in cap-sealing resins for bottled foods has been undertaken. During 1997-1999 di-(2- ethylhexyl)phthalate (DEHP) was found in seven out of 21 samples on the Japanese domestic market and in 10 out of 61 imported samples as well as a further two samples which contained di-(2-ethylhexyl)adipate (DEHA). In the period 1993-1999, of the other plasticizers diacetyl lauroyl glycerol (DALG) was only detected in domestic samples whereas diisodecyl phthalate (DIDP) and diisononyl phthalate (DINP) were only in imported samples. It was observed overall that DEHP and DEHA were restricted to use in cap-sealing resins for bottled foods. Whilst phthalates, DEHA or DALG were detected in samples in 1993 and 1995, the investigation in 1997-1999 showed fewer samples in which these plasticizers were found.     

惠州地区猪肉和猪肝中重金属污染状况的分析

目的:了解惠州地区超市和自由市场中部分猪肉、猪肝中重金属铅、镉、铜的污染状况。方法采用原子吸收火焰法测定猪肉和猪肝中的铜,用原子吸收石墨炉法测定猪肉、猪肝中的铅和镉。结果猪肉和猪肝中的铅超市合格率为93.3%,自由市场为86.7%,测定值范围猪肉为0.04～ 0.28mg/kg,猪肝为0.01～ 1.01mg/kg;猪肉和猪肝中镉合格率均为100%,测定值范围分别为0.01～ 0.08 mg/kg和0.02～ 0.16 mg/kg;猪肉中铜合格率100%,测定值范围0.23～ 0.87 mg/kg;猪肝中铜合格率超市为73.3%,自由市场只有26.7%,测定值范围4.90～ 78.9 mg/kg。结论惠州地区猪肉、猪肝的重金属污染状况不容乐观,猪肉、猪肝中均有铅超标现象,尤其是猪肝中铜元素更为严重。     

Amounts of glycosides in grapevine organs during berry development

Whole berries, leaf blades and petioles from Muscat Gordo Blanco (syn. Muscat of Alexandria), Sultana and Flame Seedless vines were sampled at intervals from three weeks after flowering to fruit ripeness. The glycosidically-bound constituents present in the samples were quantified through a determination of the glycosyl glucose. At the stage of berry ripeness, the concentration of glycosides per gram fresh weight in the leaf blades was 10–30 times higher than in the fruit. During berry development glycoside concentrations increased in leaf blades and petioles but decreased in fruit. However, when expressed on a per berry basis, the levels of glycosides in the fruit increased as ripening progressed; the levels in ripe fruit were high in Muscat Gordo Blanco and low in Sultana. Further experimentation will be needed to establish whether the glycosides are synthesised in the leaves and transported to the berries or synthesised independently in both organs.     

Role of Heavy Meromyosin in Heat‐Induced Gelation in Low Ionic Strength Solution Containing l‐Histidine

The gelation of myosin has a very important role in meat products. We have already shown that myosin in low ionic strength solution containing l ‐histidine forms a transparent gel after heating. To clarify the mechanism of this unique gelation, we investigated the changes in the nature of myosin subfragments during heating in solutions with low and high ionic strengths with and without l ‐histidine. The hydrophobicity of myosin and heavy meromyosin (HMM) in low ionic strength solution containing l ‐histidine was lower than in high ionic strength solution. The SH contents of myosin and HMM in low ionic strength solution containing l ‐histidine did not change during the heating process, whereas in high ionic strength solution they decreased slightly. The heat‐induced globular masses of HMM in low ionic strength solution containing l ‐histidine were smaller than those in high ionic strength solution. These findings suggested that the polymerization of HMM molecules by heating was suppressed in low ionic strength solution containing l ‐histidine, resulting in formation of the unique gel.     

Effects of duration of moderate increases in grain feeding on endotoxins in the digestive tract and acute phase proteins in peripheral blood of yearling calves

Effects of duration of grain feeding on the concentration of endotoxic lipopolysaccharide (LPS) in digesta throughout the digestive tract and on acute phase proteins and LPS in peripheral blood were determined in Holstein yearling calves. Twenty-five Holstein yearling steer calves received either a forage-based diet containing 92% hay and 8% of a mineral and vitamin pellet on a dry matter basis (CON) or a moderate-grain diet, obtained by replacing 41.5% of the hay in the forage-based diet with barley grain, for 3 (MG3), 7 (MG7), 14 (MG14), or 21 d (MG21) before slaughter. Immediately before slaughter, blood samples were collected from the jugular vein. Immediately after slaughter, digesta samples were collected from the rumen, jejunum, ileum, cecum, colon, and rectum. Rumen liquid digesta, digesta from the intestines, and peripheral blood plasma were analyzed for LPS. Peripheral blood plasma and serum were analyzed for the acute phase proteins amyloid A, haptoglobin, and LPS-binding protein. Feeding the grain diet increased the LPS concentration in rumen fluid linearly from 15,488 endotoxin units (EU)/mL for CON to 70,146 EU/mL for MG7. Concentrations of LPS in rumen fluid in MG14 and MG21 were 61,944 and 56,234 EU/mL, respectively, and did not differ. The LPS concentrations in jejunal digesta were much lower than that in digesta elsewhere in the digestive tract, which suggests that ruminal LPS is broken down in the abomasum or proximal jejunum. The concentration of digesta LPS in the ileum was higher than that of digesta elsewhere in the intestines and similar to that in rumen fluid. The duration of grain feeding increased the LPS concentration in digesta in the ileum and cecum and tended to increase that in the colon cubically. Concentrations of LPS in this part of the digestive tract were highest in the MG3 and MG21 groups. The highest concentrations of LPS in digesta in the cecum, colon, and rectum were 3.7, 3.8, and 5.6 times higher than that in CON, respectively. Grain feeding and the increase in LPS in digesta were not accompanied by an acute phase response or a detectable concentration of LPS in peripheral blood. The absence of LPS in peripheral blood and the lack of increase in acute phase proteins indicated that the grain feeding protocol used in the current study and the accompanying changes in LPS concentrations of the digesta did not result in systemic inflammation.     

Reproductive and neurobehavioural effects of thiabendazole administered to mice in the diet

Thiabendazole was given in the diet to provide levels of 0 (control), 0.031, 0.125, and 0.5% from 5 weeks of age of the F₀ generation to 9 weeks of age of the F₁ generation in mice, and selected reproductive and neurobehavioural parameters were measured. The average litter size and weight were significantly reduced in the high-dose group at birth. No adverse effects were observed in the sex ratio at birth. The average body weight of offspring was significantly increased in the low-dose group during the late lactation period, and was significantly reduced in the high-dose group during the lactation period. In the assessment of neurobehavioural parameters, surface righting at postnatal day (PND) 7 was significantly delayed in a dose-related manner in both sexes. Swimming limb movement at PND 14 and olfactory orientation at PND 14 were significantly depressed in the high-dose group in both sexes. In movement activity at 3 weeks of age in the F₁ generation, vertical time and number of defaecations were significantly decreased in the high-dose group in female offspring. Several adverse effects on reproductive and neurobehavioural parameters were produced at the highest dose level of thiabendazole used in the present study (equivalent to 700-1800mg/kg bw/day). Slight, dose-related delays were also seen in surface-righting ability at the two lower dose levels. The lowest dose level (equivalent to 50-180mg/kg bw/day) is 500     

Evaluation of arterial digital blood flow in dairy cows with claw horn disruption lesions using Doppler ultrasonography

Vascular changes play an important role in the pathogenesis of claw horn disruption lesions in cattle. The aim of the study was to measure arterial blood flow in the hind limbs of German Holstein cows with claw horn disruption lesions. A 10-MHz linear transducer was used to assess blood flow in the interdigital artery in the dorsal pastern region in the hind limbs of 11 non-lame and 33 lame German Holstein cows in which lameness was scored clinically. Qualitative and quantitative blood flow parameters were compared in affected limbs and unaffected contralateral hind limbs in lame cows and in the hind limbs of lame cows and non-lame cows. A pulsed-wave Doppler signal suitable for analysis was obtained in 78 of 88 limbs (33 affected and contralateral limbs, 22 limbs of control cows). Blood flow curve types 1 and 2 were predominant in the hind limbs of lame cows. Vessel diameter, end-diastolic velocity, and blood flow rate were significantly greater in lame cows than in non-lame cows and were numerically greater in moderately lame cows than in mildly lame cows. The differences in the qualitative and quantitative parameters between lame and non-lame cows were most likely caused by inflammation of the pododerm. The role of weight distribution between the paired hind limbs and the existence of claw horn disruption appeared to have an effect on the differences in local circulation in the affected and unaffected contralateral hind limbs in lame cows.     

Nutrient composition of Australian retail pork cuts 2005/2006

A study of the nutrient composition of Australian pork was undertaken to determine whether new breeding, feeding and processing methods had resulted in any changes in pork samples in the market place since surveys undertaken in previous decades. Samples of 13 popular pork cuts were purchased from randomly selected supermarkets and butchers’ stores in urban areas across the socioeconomic scale in three States of Australia, and analysed, raw and cooked, separable fat and separable lean, for nutrient composition (proximate components, minerals, vitamins) in late 2005 and early 2006. Results showed that present-day pork separable lean tissue continues to be low in fat, in line with stated objectives of practices implemented by the industry in Australia. Pork remains a good source of protein and of thiamin and other water-soluble vitamins, the latter being detected at nutritionally significant levels in fat tissue as well as lean; folate was detected in most samples, lean and fat portions. Iron content appeared to be slightly lower than in previous decades.     

不同生态区沙姆逊香料烟品质差异分析

对不同生态区沙姆逊香料烟化学成分和感官质量进行了分析,以期为筛选适宜产区和工业合理应用提供依据。结果表明,不同生态区沙姆逊香料烟化学成分差异明显,云南和四川沙姆逊香料烟总糖和还原糖含量显著高于浙江和土耳其,烟碱含量显著低于浙江和土耳其,而且四川与云南沙姆逊香料烟糖和烟碱含量差异也达到显著水平;云南沙姆逊烟叶具有较高含量的苹果酸和柠檬酸,浙江沙姆逊具有较高的草酸含量;土耳其AB 级香料烟草酸含量明显高于国内香料烟,非挥发性有机酸总量生态区间和品种间差异较大。烟叶感官质量浙江沙姆逊最好,云南次之,四川最低;国内沙姆逊香料烟中、上部烟叶感官质量总体低于土耳其AB 级烟叶。     

红车轴草不同部位中异黄酮含量的测定

采用反相高效液相色谱法对红车轴草不同部位(花、茎和叶)中四种主要异黄酮(鸡豆黄素A、芒柄花黄素、染料木素和大豆黄素)的含量进行了测定,结果表明:以占干物质计,4种异黄酮总量,叶中含量最高(0.856%),茎次之(0.403%),花中含量较低(0.258%)。鸡豆黄素A和芒柄花黄素是红车轴草中两种最主要的异黄酮,主要分布在叶中,其次是茎,花中含量较低。染料木素和大豆黄素,无论是花、茎还是叶,含量均较低。     

Impact of post-anthesis rainfall,fungicide and harvesting time on the concentration of deoxynivalenol and zearalenone in wheat

Field experiments were conducted to identify the impact of post-anthesis rainfall on the concentration of deoxynivalenol (DON) and zearalenone (ZON) in harvested wheat grain. Winter wheat plots were inoculated with Fusarium graminearum at stem extension (GS31) and prothioconazole was applied at mid-anthesis (GS65) to split plots and plots were subsequently mist irrigated for 5 days. Plots were either covered by polytunnels, irrigated by sprinklers or left as non-irrigated uncovered control plots after medium-milk (GS75). Plots were harvested either when ripe (GS92; early harvest) or three weeks later (late harvest). Fusarium head blight (FHB) was assessed each week from inoculation. At harvest, yield and grain quality was measured and grains were analysed for DON and ZON. Differences in rainfall resulted in contrasting disease pressure in the two experiments, with low FHB in the first experiment and high FHB in the second. Difference in FHB resulted in large differences in grain yield, quality and mycotoxin content. DON concentration was significantly (P < 0.05) higher in irrigated compared to covered and control plots in the first experiment, whereas in the second experiment, DON was significantly (P < 0.05) higher in the covered plots compared to the control and irrigated plots. ZON concentration was significantly (P < 0.05) higher in irrigated plots in both experiments. Later harvesting resulted in an approximate fivefold increase in ZON in the first experiment, but was not significantly different in the second experiment. Prothioconazole significantly (P < 0.05) reduced DON in both experiments, but gave inconsistent reductions to ZON. This is the first report to show that the post-anthesis rainfall can significantly increase ZON in wheat, which can increase further with a delayed harvest but may be significantly reduced with the application of prothioconazole. Importantly, in the absence of moisture late season, ZON remains at very low concentrations even when wheat is severely affected by FHB.