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121.
Po-Kai Chang Ming-Fong Tsai Chun-Yung Huang Chien-Liang Lee Chitsan Lin Chwen-Jen Shieh Chia-Hung Kuo 《Marine drugs》2021,19(8)
Refined cobia liver oil is a nutritional supplement (CBLO) that is rich in polyunsaturated fatty acids (PUFAs), such as DHA and EPA; however, PUFAs are prone to oxidation. In this study, the fabrication of chitosan-TPP-encapsulated CBLO nanoparticles (CS@CBLO NPs) was achieved by a two-step method, including emulsification and the ionic gelation of chitosan with sodium tripolyphosphate (TPP). The obtained nanoparticles were inspected by dynamic light scattering (DLS) and showed a positively charged surface with a z-average diameter of between 174 and 456 nm. Thermogravimetric analysis (TGA) results showed the three-stage weight loss trends contributing to the water evaporation, chitosan decomposition, and CBLO decomposition. The loading capacity (LC) and encapsulation efficiency (EE) of the CBLO loading in CS@CBLO NPs were 17.77–33.43% and 25.93–50.27%, respectively. The successful encapsulation of CBLO in CS@CBLO NPs was also confirmed by the Fourier transform infrared (FTIR) spectroscopy and X-ray diffraction (XRD) techniques. The oxidative stability of CBLO and CS@CBLO NPs was monitored by FTIR. As compared to CBLO, CS@CBLO NPs showed less oxidation with a lower generation of hydroperoxides and secondary oxidation products after four weeks of storage. CS@CBLO NPs are composed of two ingredients that are beneficial for health, chitosan and fish oil in a nano powdered fish oil form, with an excellent oxidative stability that will enhance its usage in the functional food and pharmaceutical industries. 相似文献
122.
123.
Kuo JM Hwang A Yeh DB Pan MH Tsai ML Pan BS 《Journal of agricultural and food chemistry》2006,54(8):3151-3156
The objective of the present study was to purify and characterize the lipoxygenase (LOX) from banana leaf (Giant Cavendishii, AAA), an unutilized bioresource. LOX was extracted, isolated, and purified 327-fold using 25-50% saturation of ammonium sulfate fractionation, hydroxyapatite column separation, and gel filtration on Superdex 200. The molecular mass of the purified LOX was 85 kDa, K(m) was 0.15 mM, and V(max) was 2.4 microM/min.mg using linoleic acid as substrate. Triton X-100 was required in the extraction medium; otherwise, no LOX activity was detected. LOX activity increased with the concentration of Triton X-100 with an optimum at 0.1%. The optimal pH of the purified LOX from banana leaf was 6.2, and optimal temperature was 40 degrees C. The LOX showed the highest reactivity toward 18:2 followed by 18:3 and 20:4. A very low reaction rate was observed toward 20:5 and 22:6. On the basis of retention time in normal phase HPLC, the products of 18:2 or 18:3 catalyzed by purified LOX were hydroperoxyoctadecadienoic acid or hydroperoxyoctadecatrienoic acid. It seems that 9-LOX is the predominant enzyme in banana leaf. Banada leaf dried at 110 degrees C for 2 h developed algal aroma. Banana leaf extract stored at 10 degrees C for 12 h formed an oolong tea-like flavor. Banana leaf extract reacted with 18:2 or soybean oil pretreated with bacterial lipase produced green and melon-like aroma, whereas the same reaction with 18:3 produced a sweet, fruity, cucumber-like flavor note. 相似文献
124.
Chen HL Yen CC Tsai TC Yu CH Liou YJ Lai YW Wang ML Chen CM 《Journal of agricultural and food chemistry》2006,54(21):8041-8047
Reactive oxygen species are associated with various diseases including cardiovascular diseases, neurological disorders, and pulmonary diseases. Extracellular superoxide dismutase (ECSOD) is an antioxidant enzyme secreted by cells to prevent overproduction of reactive oxygen species. We expressed an ECSOD gene isolated from a human aortic smooth muscle cDNA library in the methylotrophic yeast Pichia pastoris. A synthetic secretion cassette was constructed with the inducible promoter of the alcohol oxidase 1 gene (AOX1) and the yeast alpha-mating factor signal peptide. As much as 25% of the total protein was ECSOD in some transformants grown under inducing conditions. After 36 h of methanol induction, ECSOD was exported into the culture medium at a concentration of approximately 440 mg/L with an antioxidative activity of 760 +/- 20 U/mg ECSOD. Transformed yeast cells were more resistant to heat shock and H(2)O(2) oxidative stress, indicating that the human ECSOD expressed by P. pastoris had multiple biological functions. Our data suggest that the methylotrophic yeast inducible system is suitable for large-scale production of enzymatically active human ECSOD. 相似文献
125.
Bitam I Rolain JM Nicolas V Tsai YL Parola P Gundi VA Chomel BB Raoult D 《Comparative immunology, microbiology and infectious diseases》2012,35(1):71-76
We report the molecular detection of several Bartonella species in 44 (21.5%) of 204 fleas from Algeria collected from 26 rodents and 7 hedgehogs. Bartonella elizabethae and B. clarridgeiae were detected in the fleas collected on hedgehogs. Bartonella tribocorum and B. elizabethae were detected in fleas collected from rats and mice, and sequences similar to an unnamed Bartonella sp. detected in rodents from China were detected in rats as well as a genotype of Bartonella closely related to Bartonella rochalimae detected in fleas collected on brown rats (Rattus norvegicus). 相似文献
126.
Chih-Shen Chuang Kuang-Chung Tsai Ming-Kuang Wang Chia-Chih Ou Chun-Han Ko Ing-Luen Shiau 《Wood Science and Technology》2008,42(7):593-607
Acrylic emulsion based painted red lauan plywood (Parashorea spp.) is most commonly used for indoor furnishings. This study investigated the enhancement of the fire retardance of painted
plywood by interaction among four major components of intumescent formulation: (1) acrylic emulsion resin as binder resin
(BR), (2) pentaerythritol as carbonizing substance (CS), (3) melamine as foam producing substance (FPS) and (4) ammonium polyphosphate
as dehydrating agent (DA). Effects of changing BR/CS ratios (designated as FRA series) and FPS/DA ratios (designated as FRM
series) on flame-retardance of painted plywood were investigated using a cone calorimeter. The intumescent formulation significantly
enhanced fire retardancy of painted plywood by exhibiting lower peak release rates and longer times to reach peak release
rates, compared with uncoated plywood (UP) panel and plywood panel solely coated with acrylic emulsion resin. Lower BR content
in the FRA series and lower FPS content in the FRM series were shown to enhance flame retardancy of painted plywood. The positive
correlation between total heat release values under increasing combustion duration and incremental changes of BR and FPS contents
in two series further verified the above findings. Consistent with the observed flame retardancy enhancement of painted plywood,
lower heats of combustion and weight losses for paints in the FRM series were also identified by oxygen bomb calorimeter measurements
and thermogravimetrical analysis. Infrared analysis of the chars indicated the formation of phosphate ester linkages with
the lowest BR content in the FRA series and the lowest FPS content in the FRM series showing superior enhancements of flame
retardancy for painted red lauan plywood. 相似文献
127.
Identification of natural variants affecting chlorophyll content dynamics during rice seedling development
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Po‐Chun Lin Yu‐Chang Tsai Sheng‐Kai Hsu Jen‐Hsiang Ou Chen‐Tuo Liao Chih‐Wei Tung 《Plant Breeding》2018,137(3):355-363
Seedling vigour is an important characteristic in relation to crop growth and yield. Traits such as photosynthetic capacity and chlorophyll content contribute significantly to seedling establishment at the early growth stage in various crop species, including rice. A diverse panel of 227 rice varieties from several countries was evaluated to determine chlorophyll contents at multiple time points during the seedling stage using a soil–plant analysis development (SPAD) meter, a non‐destructive portable device. Using new statistical approaches, several chromosomal regions associated with variations in chlorophyll content in the third leaf at 13, 16 and 19 days after imbibition were detected. A single nucleotide polymorphism (SNP) cluster on the end of chromosome 11 was significantly associated with the onset of leaf senescence. This region was enriched with genes related to cell death and the stress response. We have identified rice germplasm showing delayed‐senescence phenotypes, these could be suitable donors and genetic resources for breeding, and the use of significant SNP markers associated with these traits could enhance the efficiency of their selection in breeding programmes. 相似文献
128.
Ching-Chu Tsai Li-Fen Hung Jeng-Der Chung Shiang-Jiuun Chen Ching-Te Chien Wen-Yuan Kao Ling-Long Kuo-Huang 《Annals of Forest Science》2018,75(2):52
Key message
The radial wood growth curves of Cinnamomum kanehirae Hayata (an endangered species of subtropical Taiwan) exhibit an S shape. The dominant trees displayed a larger radial growth than the codominant trees, and their growth was more sensitive to air temperature.Context
Knowledge of wood radial growth is important for evaluating the factors that limit tree growth performance. The relevant experiments have mostly been conducted in cold and temperate ecosystems, but rarely in subtropical ecosystems.Aims
In this study, we aimed to construct a unified radial growth model for Cinnamomum kanehirae Hayata and to identify its sensitivity to temperature.Methods
The wood radial increments were quantified for 3 years by either pinning or microcoring. The radial wood growth curves were modelled integratively by semiparametric regression and individually by curve fitting. The effects of tree social class, interannual and environmental factors on radial growth were analysed quantitatively.Results
A unified S-shaped growth model for C. kanehirae was successfully constructed. By including the social class effect, the model was significantly improved. The maximum radial increment (A) was significantly correlated with the maximum growth rate (μ); both A and μ were significantly higher in dominant than in codominant trees. The time-varying radial growth rate was more sensitive to air temperature in dominant than in codominant trees.Conclusion
Semiparametric models revealed an S-shaped growth curve of C. kanehirae and confirmed the higher temperature sensitivity of dominant trees compared to codominant trees in humid subtropical areas.129.
Border control is the primary method to prevent rabies emergence. This study developed a quantitative risk model incorporating stochastic processes to evaluate whether border control measures could efficiently prevent rabies introduction through importation of cats and dogs using Taiwan as an example. Both legal importation and illegal smuggling were investigated. The impacts of reduced quarantine and/or waiting period on the risk of rabies introduction were also evaluated. The results showed that Taiwan’s current animal importation policy could effectively prevent rabies introduction through legal importation of cats and dogs. The median risk of a rabid animal to penetrate current border control measures and enter Taiwan was 5.33 × 10−8 (95th percentile: 3.20 × 10−7). However, illegal smuggling may pose Taiwan to the great risk of rabies emergence. Reduction of quarantine and/or waiting period would affect the risk differently, depending on the applied assumptions, such as increased vaccination coverage, enforced custom checking, and/or change in number of legal importations. Although the changes in the estimated risk under the assumed alternatives were not substantial except for completely abolishing quarantine, the consequences of rabies introduction may yet be considered to be significant in a rabies-free area. Therefore, a comprehensive benefit-cost analysis needs to be conducted before recommending these alternative measures. 相似文献
130.
Kaelberer T Fedotov VA Papasimakis N Tsai DP Zheludev NI 《Science (New York, N.Y.)》2010,330(6010):1510-1512
Toroidal multipoles are fundamental electromagnetic excitations different from those associated with the familiar charge and magnetic multipoles. They have been held responsible for parity violation in nuclear and particle physics, but direct evidence of their existence in classical electrodynamics has remained elusive. We report on the observation of a resonant electromagnetic response in an artificially engineered medium, or metamaterial, that cannot be attributed to magnetic or charge multipoles and can only be explained by the existence of a toroidal dipole. Our direct experimental evidence of the toroidal response brings attention to the often ignored electromagnetic interactions involving toroidal multipoles, which could be present in naturally occurring systems, especially at the macromolecule level, where toroidal symmetry is ubiquitous. 相似文献