Seasonal variations of chemical constituents in the muscle and viscera of small abalone fed different diets

SUMMARY: The seasonal changes in levels of chemical constituents in the muscle and viscera of small abalone Haliotis diversicolor fed gracilar and an artificial diet were investigated. Muscle yields were higher in winter and spring. In October specimens, total adenosine 5'-triphosphate (ATP)-related compounds (ARC), total free amino acids (FAA), and glycogen in both muscle and viscera decreased markedly. The artificial diet fed to small abalone had much higher glycogen in the muscle than those fed on gracilar, and showed a great seasonal change. Total amounts of ARC in the muscles were higher through March to July, while those in the viscera were maximal in January. Taurine, arginine, glycine, glutamic acid, and alanine were the major FAA in both tissues, accounting for 81–94% of the total FAA. Total amounts of FAA in the muscles were higher in the samples collected from winter and early spring than in other seasons. Glycine, glutamic acid, and adenosine monophosphate might be the most important taste components related to the palatability of small abalone. Their total amounts in the muscles of the two specimens were considerably high in December to March. This finding suggested that small abalone produced in winter and early spring might be more palatable.     

Starch characteristics and their influences on in vitro and pig prececal starch digestion

The main objective of this research was to study the characteristics of starch granules and their influences on in vitro and pig prececal starch digestion of corn, dehulled barley, wheat, and potato. Scanning electron microscopy was used to study the starch endosperm structure in the parent material as well as in vitro starch digestion. The results showed that corn starch granules were polyhedral, with a diameter ranging from 2 to 10 μm, whereas those of dehulled barley and wheat were spherical, with a diameter ranging from 5 to 20 μm. Potato had the largest starch granules among starch sources reported herein, with oval spheres of 10-50 μm in diameter. In vitro starch hydrolysis showed that starch granules of corn degraded faster than the starch of dehulled barley and wheat, with the potato starch being degraded the slowest. The in vivo digestibility trial using ileal-cannulated pigs confirmed the starch degradation of grains. The in vitro (x, %) and in vivo (y, %) digestibility were highly correlated [y = 6.5304x - 538.48 (R(2) = 0.9924)]. On the basis of the results, in vitro starch hydrolysis might be useful in predicting in vivo prececal starch digestibility. The digestion kinetic characteristics of different starch sources might be employed to evaluate the starch digestive rate at the pig ileum.     

Shedding pattern and serological profile of porcine circovirus type 2 infection in cesarean-derived, colostrum-deprived and farm-raised pigs

Six 5-week-old porcine circovirus type 2 (PCV2)-free, cesarean-derived, colostrums-deprived (CDCD) pigs were inoculated intranasally with 10(6) TCID(50) of PCV2. Four CDCD pigs were untreated cohabitants. Forty farm-raised pigs from two PCV2-contaminated herds were randomly selected for PCV2 trace investigations. Blood, nasal, oropharyngeal and fecal samples were collected from all tested pigs weekly. The PCV2 DNA shed at 6-11 and 7-12 weeks of age for PCV2-inoculated pigs and cohabitants, respectively. All the CDCD pigs exhibited seroconversion after PCV2 exposure. In the farm-raised animals, PCV2 shed at 9-15 weeks of age and seroconversion started at 11 weeks of age. Collectively, the pigs had a prolonged PCV2 shedding period following viral exposure, and growing pigs were the source of horizontal PCV2 transmission in PCV2-infected herds.     

Anesthesia cutoff phenomenon: interfacial hydrogen bonding

Anesthesia "cutoff" refers to the phenomenon of loss of anesthetic potency in a homologous series of alkanes and their derivatives when their sizes become too large. In this study, hydrogen bonding of 1-alkanol series (ethanol to eicosanol) to dipalmitoyl-L-alpha-phosphatidylcholine (DPPC) was studied by Fourier transform infrared spectroscopy (FTIR) in DPPC-D2O-in-CCl4 reversed micelles. The alkanols formed hydrogen bonds with the phosphate moiety of DPPC and released the DPPC-bound deuterated water, evidenced by increases in the bound O-H stretching signal of the alkanol-DPPC complex and also in the free O-D stretching band of unbound D2O. These effects increased according to the elongation of the carbon chain of 1-alkanols from ethanol (C2) to 1-decanol (C10), but suddenly almost disappeared at 1-tetradecanol (C14). Anesthetic potencies of these alkanols, estimated by the activity of brine shrimps, were linearly related to hydrogen bond-breaking activities below C10 and agreed with the FTIR data in the cutoff at C10.     

Germination of peanut kernels to enhance resveratrol biosynthesis and prepare sprouts as a functional vegetable

Bioactive benefits of resveratrol in the diets have attracted extensive interests of the public. Peanut is one of the potent natural sources of resveratrol. In this study, germination of peanut kernels to enhance resveratrol biosynthesis and preparation of sprouts as a functional vegetable was conducted. When the rehydrated kernels of three peanut cultivars were germinated at 25 degrees C and relative humidity 95% in dark for 9 days, resveratrol contents increased significantly from the range of 2.3 to 4.5 microg/g up to the range of 11.7 to 25.7 mug/g depending upon peanut cultivar. In comparison with the sprout components, resveratrol contents were highest in the cotyledons, slightly lower in the roots, and not detected in the stems. When the sprouts were heated in boiling water for 2 min, resveratrol contents varied in a limited range. Methanol extracts of the freeze-dried sprouts exhibited potent 1,1-diphenyl-2-picryl-hydrazyl scavenging activity and antioxidative potency against linoleic acid oxidation. These activities increased with an increase of germination time. After 9 days of germination, total free amino acid, sucrose, and glucose contents increased significantly while crude protein contents decreased and the large sodium dodecyl sulfate polyacrylamide gel electrophoresis protein molecules of the kernels were extensively degraded. From a practical viewpoint, it is of potency to prepare peanut sprouts as a functional vegetable.     

The Adsorption of Fluoride Ion from Aqueous Solution by Activated Alumina

The adsorption of fluoride ion in aqueous solution by using alumina was studied in this research. The experimental resultsindicated that the removal efficiency was influenced significantly by solution pH and the optimum operating pH wasfound to be in the range of 5 to 7. For neutral and acidic solutions, the adsorption capacities of fluoride by alumina wasinterfered by the presence of sulfate. The Langmuir and Freundlich isotherms can well describe the equilibrium behaviorsof the adsorption processes. The experimentally determined lowvalues of activation energy indicate nonspecific adsorption isthe predominant mechanism. The surface reaction-limiting batchkinetic model can adequately describe the removal behaviors offluoride ion by alumina adsorption in the batch system.     

Immunomodulatory properties of Grifola frondosa in submerged culture

Maitake (Grifola frondosa) is a popular mushroom in Asia for its tasty flavor and immune-stimulating property. The aim of the study is to investigate the innate immunity augmentation effects of different extracts of mycelia and culture filtrate from G. frondosa in submerged cultures. The hot water extract of mycelia showed the strongest cytokine induction effect as a function of its concentration in human whole blood culture. The most potent fractions of hot water extract, Fr. I and II, were mainly composed of polysaccharides with molecular masses of 43-140 and 13-38 kDa, respectively. These fractions (0.025 mg/mL) showed marked activity in enhancing phagocytosis of human polymorphonuclear neutrophils (PMN). In parallel, the expression of CD11b, an early marker of PMN activation, was also up-regulated dose dependently. This result suggested that complement receptor 3 was primed by these fractions. In addition to activation of phagocytes, these bioactive fractions also increased human peripheral blood natural killer cell cytotoxicity. These results imply that the relatively low molecular mass polysaccharides isolated from mycelia of G. frondosa can enhance innate immunity in vitro and therefore may serve as biological response modifiers.