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711.
Properties of foxtail millet (Setaria italica Beauv.) starches have been studied. Amylose content ranged between 3.3 and 11.4%. Starch content was from 67.5 to 68.7%.
The onset temperature (To) of all samples ranged from 66.4 to 69.6°C, peak temperature (Tp) ranged 71.0 to 74.2°C, and their gelatinization enthalpy varied from 0.44 to 8.22 J/g, respectively. A highest gelatinization
temperature was obtained for Bongseongjaerae (69.6°C). The enthalpy of the gelatinization (Δ H
gel
) was highest in Andongjaerae. The highest peak, highest breakdown, very high final viscosity, and very low setback were noted
in Jucheonjaerae. The starch granule sizes ranged 10.1–25.0 in length and 4.7–12.5μm in diameter. X-ray diffraction angles
indicated that all starch samples possess a typical A-type crystallinity. 相似文献
712.
Na Na Kim Jehee Lee Hamid R. Habibi Cheol Young Choi 《Fish physiology and biochemistry》2013,39(3):417-429
The caspase-3 appears to be a key protease in the apoptotic pathway. We identified caspase-3 complementary DNAs from the ovaries of the protandrous cinnamon clownfish (Amphiprion melanopus), and investigated its mRNA and proteins, and activity levels during the sex change (I, mature male; II, male at 90 days after removing of the female; and III, mature female). The nucleotide sequence of the caspase-3 cDNA was 969 base pairs in length with open reading frames encoding peptides of 282 amino acids. The caspase-3 mRNA and protein, and activity levels in stages of the mature gonad are higher than those of the development gonad stage. To understand the effect of gonadotropin-releasing hormone (GnRH) on gonad apoptosis, we examined expression of genes caspase-3 mRNA and activity level in immature cinnamon clownfish gonads after GnRH analogue (GnRHa). The findings support the hypothesis that caspase-3 expression is associated with both testicular and ovarian development, and suggests that it may play a role in the control of ovarian development in cinnamon clownfish. Also, we demonstrate that GnRH agonists stimulate caspase-3 production which can in turn stimulate apoptosis. The present study provides a framework for better understanding of the role of caspase-3 during sex change processes in fish. 相似文献
713.
Kim Van Van Truong Dinh Hoai Kurt Buchmann Anders Dalgaard Nguyen Van Tho 《南方农业学报》2012,43(4):520-523
[目的]探讨3种不同药物处理方式对台湾棘带吸虫引起的鲤鱼幼鱼急性鱼鳃传染病(开放性鳃病)的防治效果.[方法]在试验初期,将1620条鲤鱼幼鱼(70日龄)鱼鳃自然感染台湾棘带吸虫,随后分成4组,分别采用CuSO4、福尔马林和吡喹酮不同方式处理6周,与对照(自然喂食、不使用任何化学药剂)比较防治鲤鱼幼鱼急性鳃传染病的效果.[结果]感染台湾棘带吸虫的幼鱼生长缓慢,其身长和体重增长均较慢.施药后,幼鱼台湾棘带吸虫后期囊幼虫感染强度减少.在每千克饲料中分别添加50和75 mg吡喹酮喂食幼鱼5d,可以杀死鱼鳃中所有的台湾棘带吸虫后期囊幼虫,且鱼鳃恢复正常;面使用25 mg吡喹酮,仅有35%的后期囊幼虫死亡.所有不同浓度CuSO4处理(0.3、0.4和0.5mg/kg冲洗浸泡24 h及以3.0、4.0和5.0 mg/kg冲洗浸泡10m)和福尔马林处理(20、25和30 mg/kg冲洗浸泡及200、250和300 mg/kg短时间冲洗浸泡)均不能杀死台湾棘带吸虫后期囊幼虫.[结论]经普通化学药剂CuSO4或福尔马林冲洗浸泡,不能防治由台湾棘带吸虫后期囊幼虫引起的鲤鱼开放性鳃病,但50~75 mg吡喹酮/kg饲料可以在5d内治疗该病. 相似文献
714.
Kim DK Jeong SC Gorinstein S Chon SU 《Plant foods for human nutrition (Dordrecht, Netherlands)》2012,67(1):71-75
The aim of this investigation was to evaluate the biological, alcohol dehydrogenase (ADH) and antiproliferative activities
of different extracts of mungbean seeds and sprouts. All extracts from the sprouts showed higher contents of total phenolics
(TP), total flavonoids (TF), and 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging activity than from seeds. The highest
DPPH and tyrosinase inhibition activities were registered in ethyl acetate (EtOAc) extract. ADH activity of methanol (MeOH),
n-hexane (n-hexane) and n-butanol (n-BuOH) extracts from sprouts was significantly higher (P < 0.05) than from seeds. However, the highest ADH activity was found in water extract of seeds. According to 3-(4, 5-dimethylthiazol
-2-yl)-2, 5-diphenyltetrazolium bromide) (MTT) assay, extracts from sprouts were more effective against Calu-6 (human pulmonary
carcinoma) and SNU-601 (human gastric carcinoma) cells than from seeds. EtOAc extract showed the highest antiproliferative
activity in both sprouts and seeds, followed by n-hexane extraction. During sprouting of mungbean, all the studied components
significantly increased. In conclusion, the extracts of sprouts are more effective than from seeds and could be a potential
source of antioxidants linked with health benefits. 相似文献
715.
Hodong Kim 《Fibers and Polymers》2012,13(6):762-768
This study investigates the possibility of utilizing basalt chopped fiber in order to prepare a thermally stable fiber reinforced composite. Bi-component resin system using epoxy and benzoxazine monomer is proposed and its cure characteristic is evaluated by FT-IR and DSC. Copolymerization of epoxy resin upon curing with benzoxazine is carried out in the absence of a strong catalyst. Through the evaluation of T g of the epoxy-benzoxazine copolymer resin and its composite, it is clear that the incorporation of basalt fiber in composite has a great role and advantage. Also, this study systematically evaluates the apparent char yield and net char yield gain of the composites using TGA thermograms. Based on the results of DSC and TGA, it is advised that the favorable composite composition can be prepared from the range of 20 % to 50 % of epoxy content with 10 % of basalt fiber. 相似文献
716.
Silsesquiazane (SSQZ), one of the branched forms of polysilazane, was blended with polystyrene (PS), poly(methyl methacrylate) (PMMA), poly(iso-butyl methacrylate) (PBMA), and poly(vinyl acetate) (PVAc) to produce organic-inorganic hybrid materials. The polymers were selected to provide specific interaction, such as ??-?? interaction or hydrogen bonding, with SSQZ. AFM studies revealed that carbonyl containing polymers, PMMA, PBMA, and PVAc were miscible with SSQZ while PS was immiscible. DSC analysis of the hybrids also supported the miscibility behaviours of the system. The glass transition behaviour of SSQZ/PS showed individual transition temperature corresponding to the each component while SSQZ/carbonyl-containing polymers displayed one transition temperature that matched with the theoretically calculated values following the Kwei equation. Among the miscible hybrid system, the interaction with SSQZ increased in the order of PMMA> PBMA> PVAc, as determined by the q value in the Kwei equation. This result was confirmed by determining the degree of hydrogen bonding in FT-IR spectra. Thermal stability of organic polymers was improved by incorporating SSQZ regardless of the miscibility. 相似文献
717.
In this study, we investigated the effects of enzymatic hydrolysis on polyamide fabrics by using bromelain as an enzyme. The
hydrolytic activity of bromelain was evaluated on the basis of the number of carboxylic groups formed on the surface of the
polyamide fabrics, and it was measured using the reactive dye absorbance. In addition, 2,4,6-trinitrobenzenesulfonic acid
was added as an indicator to measure the number of amino groups released into the treatment liquid by the changes in color
of the liquid. The optimum treatment conditions were bromelain pH of 6.0, treatment time of 120 min, temperature of 50 °C,
concentration of 10 % (owf), and L-cysteine concentration of 70 mM. The weight loss in the fabric after treatment with bromelain
facilitated by L-cysteine significantly improved; however, the tensile strengths of the polyamide fabrics did not show any
differences. Bromelain hydrolysis of the polyamide fabrics thus improved hydrophilicity without damaging the fabrics’ strength. 相似文献
718.
Microcrystalline cellulose was reacted with catalytic amounts of 2, 2, 6, 6-tetramethyl-1-piperidine oxoammonium salt (TEMPO),
sodium hypochlorite and sodium bromide in Na2CO3/NaHCO3 buffer solution at different temperatures (30 °C, 40 °C, 50 °C). The oxidation procedures included first oxidation and second
oxidation. The yield of cellouronic acid produced in the second oxidation was higher than the yield of cellouronic acid produced
in the first oxidation at the same oxidation temperature. Moreover, an interesting “high-hydrophilic” phenomenon appeared
at higher temperature during microcrystalline cellulose second oxidation (30 °C, 40 °C, 50 °C). Properties associated with
the chemical characteristics are discussed by XRD, FTIR, 13C-NMR and Laser Particle Analyzer in view of its interesting high-hydrophilic effects. 相似文献
719.
The dynamics of the friction yarn formation process is described in terms of the dynamic behavior of the process state variables.
Production efficiency and product quality of friction spinning are influenced by these process state variables. This study
was performed with the intention of setting up a dynamic model based on mass balance in order to delineate the dynamic behavior
of the cross-sectional area of the in-process bundle on the friction drum surface and to attain the distribution profiles
of the cross-sectional area in transient state and in steady state as well. Then, simulation results were compared with those
of the experiment, while the input variation was used as a test signal. Theoretical model shows that the bundle thickness
on the friction drum has the dynamic characteristics of an integrating system with interval due to the finite length of the
input fleece zone, and is in good correspondence with the results of the experiment. A periodic change in the fleece feeding
rate led to the fact that there was a specific range of the fluctuation wavelength in the fleece feeding rate, whereas a change
in the in-process bundle thickness completely disappeared or became locally maximized in certain wavelength areas. This could
lead to a magnification or inaction of the perturbations with the corresponding wavelength in the bundle thickness; a bundle
thickness irregularity. Experiments also identified that the theoretical model accurately described the fiber accumulation
dynamics in a friction spinning process. 相似文献
720.
Taejo Kim Juan L. Silva Pramuk Parakulsuksatid Dja Shin Wang 《Journal Of Aquatic Food Product Technology》2013,22(4):385-393
One collagenase (CLS1®) and two proteases (Proleather FG-F® and Protease N®) were used to deskin the peritoneal membrane of catfish nuggets. The factors were used in a full factorial experiment design: enzyme solution concentration (0.2, 0.3, and 0.4% by weight), temperature of enzyme solution (30, 37, and 44°C), and immersion time (10, 15, and 20 min). Contour plots showed that the enzyme Proleather FG-F® maximized whiteness of catfish nuggets at 40–44°C for 15–19 min. Treatment of the enzyme Proleather FG-F® at 0.2% for 15 min had the highest yield (103.4%) at 44°C. Enzymatic skinning has potential in removing the peritoneal membrane from catfish nuggets, improving color (whiteness), and yield. 相似文献