天然红心鸭蛋中的类胡萝卜素及对S180肿瘤抑制作用的初步研究

本文对天然红心鸭蛋中的类胡萝卜素做了初步分析,同时探讨了红心鸭蛋中的类胡萝卜素对S180肿瘤的作用。初步结果表明,天然红心鸭蛋中的类胡萝卜素包含有虾青素及其它一些种类的类胡萝卜素。天然红心鸭蛋中的类胡萝卜素对肝匀浆MDA的产生有显著的抑制作用, 对昆明小白鼠S180肿瘤具有显著的抑制作用,且具有明显的量效关系。低、中、高剂量组的类胡萝卜素对肿瘤的抑制率分别为23.2%、35.7%和42.9%,对肿瘤小鼠的内脏指数有显著改善作用,并可显著地降低肿瘤小鼠血清MDA含量。     

Fine structure and formation of the eggshell in scorpionfly Panorpa liui Hua (Mecoptera: Panorpidae)

The morphology and formation of the eggshell in the scorpionfly Panorpa liui Hua were examined with light microscopy and scanning and transmission electron microscopy. During oogenesis of the scorpionfly, the follicle cells multiply by mitotic divisions and diversify into four morphologically distinct subpopulations, three of which are engaged in the eggshell formation and mold various parts of chorion. The eggshell consists of three layers: An inner vitelline membrane, an outer chorion, and a precursor extrachorion. The chorion constitutes a very compact endochorion, a rough fibrillar exochorion, and a polygonal meshwork of elevated ridges. At proximal end of ovarioles the chorion of matured oocyte is covered with a loose membrane, which might be the remnant of follicle cells. The jelly substance, which acts as lubricant to protect the oviducts and ovulated eggs during ovulation, might add to the top of polygonal ridges as the outermost extrachorion after oviposition. The eggshell formation process in Panorpa is tentatively proposed. Microsc. Res. Tech. 2009. © 2009 Wiley-Liss, Inc.     

Signal Transduction of Barnacle Egg-Hatching Pheromone: Pharmacological Assays Indicate a Comparatively Simple Mechanism of Eicosanoid Action

Eicosanoids are generally regarded as autocoids that act via G-protein-linked receptors. There are exceptions to this model, however, both in terms of function and mechanism of action. The present paper concerns one such example, an hydroxy fatty acid that acts as a pheromone, not an autocoid, in inducing barnacle egg hatching. Preliminary findings of pharmacological assays on the mechanism of action of this eicosanoid pheromone do not support the involvement of G proteins, Ca²⁺, or protein kinase C in signal transduction. Instead it is concluded, tentatively, that barnacle egg hatching pheromone acts via a comparatively simple pathway involving the second messenger, cyclic AMP.     

The influence of different single dietary sources on moult induction in laying hens

An investigation was carried out to assess the possibility of using single dietary sources as alternatives to feed deprivation for the induction of moult in commercial laying hens. The study involved six dietary groups of 29 laying hens: unmoulted, dried tomato pomace, alfalfa meal, rice bran, cumin seed meal and feed withdrawal. The birds received the above diets during the moulting period (11 days), and body weight loss and ovary weight regression were measured. Post‐moult production parameters (number of eggs produced per hen per day, egg weight, shell weight, yolk colour and Haugh unit) were measured for 12 weeks. Results showed that all dietary sources were as effective as feed withdrawal in causing ovary weight regression in birds. Birds provided with tomato pomace or alfalfa showed lower weight losses than feed‐deprived birds at the end of the moulting period. Hens moulted by tomato pomace or alfalfa exhibited post‐moult levels of egg production over a 12 week period that were superior to those of hens moulted by feed withdrawal. Post‐moult eggs laid by hens moulted by all dietary sources were of comparable quality to eggs from feed‐deprived hens and superior to those from unmoulted hens. As fibrous feeds with low metabolisable energy and an appreciable amount of protein, dried tomato pomace and alfalfa meal may be fed to hens on an ad libitum basis for effective moult induction while reducing the stress of severe starvation and retaining comparable egg quality and production. Copyright © 2007 Society of Chemical Industry     

Tocopherols, Retinol and Carotenes in Chicken Egg and Tissues as Influenced by Dietary Palm Oil

Incorporation of palm oil (PO) increased the α-and γ-tocotrienol content of eggs, liver, meat and adipose tissue. Total tocotrienols were higher in eggs, liver and adipose tissue of hens fed 1.5% PO than those fed 3.5% PO. An increase in retinol was observed in the eggs, liver and dark meat of hens fed PO diet. Feeding diets containing 1.5 or 3.5% PO increased the α-and β- carotenes in eggs and liver tissue. However, carotenoids were not detected in white meat, dark meat or adipose tissue. Dark meat incorporated higher levels of tocopherols and retinol than white meat. The diets had no effect on egg or yolk weight. Egg yolks from hens fed PO had higher yolk color than those without PO. Addition of tocopherol mix in the control diet increased total tocopherol content in all tissues.     

不同澄清剂在消除酿造食醋二次沉淀上的应用

为了提高酿造食醋质量，减少食醋中沉淀物的含量，探讨了利用壳聚糖、蛋清液和明胶在消除酿造食醋二次沉淀上的清除效果，并对其使用效果和使用后的食醋口感进行了比较。结果表明：使用蛋清液和明胶消除酿造食醋二次沉淀后，其效果和食醋的口感优于使用壳聚糖。     

Production of phospholipids from spray-dried egg yolk by consecutive in situ solid phase extraction with acetone and ethanol

Egg yolk lipids were extracted and fractionated into neutral lipids and phospholipids using acetone followed by ethanol as eluting solvents to a column consisting of spray-dried egg yolk. This technique, named in situ solid phase extraction, can be performed with spray-dried egg yolk due to the properties of this material. The effect of temperature, flowrate and scale has been studied. Results suggest that the methodology is suitable for industrial implementation.     

Structural and Rheological Properties of Aerated High Sugar Systems Containing Egg Albumen

ABSTRACT: Structural and rheological properties have been investigated for an aerated system containing a high content of invert sugar and 2 to 10 wt% egg albumen. The specific gravity and the overrun were found to be influenced by the protein concentration and the whipping time. The systems exhibited rheopexy and shear-thinning at high shear rate, with flow data fitted to a power-law model. At small deformations, viscous character was found to dominate over elastic character over the frequency range 10⁻² to 10 Hz. Images taken from confocal microscopy indicated that mean bubble size and concentration varied systematically with protein concentration and whipping time, and that more protein accumulated on the bubble surfaces as whipping proceeded. The study of this model system illustrates how the texture of a high sugar content aerated food depends on protein content and whipping conditions.     

Species identification of meat products by ELISA

ELISA methods used in this study are proved to detect low contents of animal species (pork, beef, sheep and poultry), even in highly processed foods. They present the advantages of being robust, cheap and easy to perform. Nevertheless, F factors, determining the threshold values of the test, need to be validated for each species.