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971.
Effects of dietary substitution of fishmeal with the combined dry microalgae,Nannochloropsis oceanica (NO) biomass residue and casein on growth and body composition of juvenile abalone (Haliotis discus) 下载免费PDF全文
Sung Hyo Myung Won‐Gwan Jung Hee Sung Kim Ye Eun Kim Sung Hwoan Cho Min Seok Jwa Pil Youn Kim Mun Kwan Kim Min‐Woo Park Byeng‐Hak Kim 《Aquaculture Research》2016,47(1):341-348
The effects of dietary substitution of fishmeal with the combined dry Nannochloropsis oceanica (NO) biomass residue and casein on growth performance and carcass composition of juvenile abalone was determined. One thousand two hundred and sixty juvenile abalone were randomly distributed into the 18 L plastic rectangular containers. Five experimental diets in triplicate were prepared. The 28% fishmeal was included into the control (Con) diet. The 25%, 50%, 75% and 100% fishmeal were substituted with the combination of graded levels of dry NO biomass residue and casein, referred to as the NO25, NO50, NO75 and NO100 diets respectively. Finally, the salted sea tangle (ST), Laminaria japonica was prepared to compare the effect of the experimental diets on performance of abalone. The essential amino acids, such as isoleucine, leucine, phenylalanine, threonine and valine tended to increase with dietary substitution of fishmeal with NO biomass residue in the experimental diets. Arginine tended to decrease with dietary substitution of fishmeal with NO biomass residue. Survival of abalone fed the experimental diets was higher than that of abalone fed the ST diet for 16 weeks. Weight gain and specific growth rate (SGR) of abalone fed the NO100 diet were higher than those of abalone fed the all other diets. Weight gain and SGR of abalone linearly increased with dietary substation of fishmeal with NO. Shell length of abalone tended to increase with dietary substitution of fishmeal with the combined dry NO biomass residue and casein. The chemical composition of the soft body of abalone was different among treatments except for moisture content. In conclusion, fishmeal in the diets for abalone could be completely replaced with the combined dry NO biomass residue and casein when the 28% fishmeal was included. 相似文献
972.
Substitution effect of sea tangle (ST) (Laminaria japonica) with tunic of sea squirt (SS) (Halocynthia roretzi) in diet on growth and carcass composition of juvenile abalone (Haliotis discus,Reeve 1846) 下载免费PDF全文
B. Jang P.Y. Kim H.S. Kim K.W. Lee H.J. Kim D.G. Choi S.H. Cho B. Min K. Kim H. Han 《Aquaculture Nutrition》2018,24(1):586-593
Substitution effect of sea tangle (ST) with tunic of sea squirt (SS) in diet on growth and carcass composition of juvenile abalone was determined. One thousand four hundred and seventy abalones were distributed into 21 containers. Six formulated diets in triplicate were prepared. A 200 g/kg ST was included into the ST0 diet. The 200, 400, 600, 800 and 1000 g/kg of ST were substituted with the same amount of tunic of SS, referred to as the ST200, ST400, ST600, ST800 and ST1000 diets, respectively. Finally, Undaria was prepared to compare effect of the formulated diets on performance of abalone. The experimental diets were fed to abalone for 16 weeks. Weight gain of abalone fed the ST400 diet was higher than that of abalone fed the ST0, ST600, ST800 and ST1000 diets and Undaria. Weight gain of abalone fed the formulated diets was higher than that of abalone fed the Undaria. The chemical composition of the carcass of abalone was affected by dietary substitution of ST with tunic of SS. In conclusion, ST could be completely substituted with tunic of SS without retardation in performance of abalone. Abalone fed the ST400 diet substituting 400 g/kg ST with tunic of SS achieved the best growth. 相似文献
973.
In this work, surface acetylation of cellulose nanocrystals was performed to improve their interfacial adhesion with hydrophobic polymer matrix and to restore their thermal stability by removing the sulfate groups. The morphological, chemical, and thermal characteristics of the surface-modified cellulose nanocrystals (ACNs) were confirmed by field emission-transmission electron microscopy, X-ray diffraction, Fourier-transform infrared spectroscopy, and X-ray photoelectron spectroscopy. Furthermore, poly(butylene succinate) (PBS)/ACNs nanocomposites were also prepared via melt-mixing process, and the reinforcing effects of ACNs on the thermal, mechanical, and biodegradable properties of the nanocomposites were investigated. The Young’s modulus and tensile strength of the PBS/ACN nanocomposites increased from 115.36 and 33.67 MPa for the neat PBS to 130.55 MPa and 39.97 MPa, respectively. The thermal stability and biodegradability of the nanocomposites also increased with increasing ACN content. 相似文献
974.
A study was made of measures to revitalize mountain ginseng cultivation in the eastern mountainous area of Muju, Jinan and Jangsu municipalities of North Jeolla province, South Korea. The targeted area is typical forested land and is utilized for the cultivation of ginseng. Access to seeds and seedlings for mountain ginseng cultivation is relatively easy in North Jeolla province, and the species is cultivated widely (on 63 % of the area of the province and by 74 % of farmers). This study investigated the current state of mountain ginseng cultivation and business management, including production costs and subsidy, sales and distribution system, and other business management concerns. A survey was conducted on 86 mountain ginseng-cultivating farming households living in the targeted area in 2013. It is concluded that to achieve greater production an aggressive government policy promoting the renting out of suitable sites for mountain ginseng cultivation in national and public production forestland to individual farms and farming cooperatives is necessary. Further research on increasing the survival rate of cultivated mountain ginseng (CMG) until harvesting and preventing damage by wild animals is also deemed necessary. More effective use of related municipal budget subsidy needs to be supported selectively to the enterprising farmers who aggressively pursue mountain ginseng cultivation and business management. Opening CMG retail stores to realize sustainable income growth and developing various processed products will increase farm income. The government needs to introduce policies to sustain consumer trust in CMG through initiatives such as establishing a CMG quality management system for growers, distributing government-approved seeds, and implementing a government-based CMG purchase system. 相似文献
975.
Kyoung T Kim Gyu H Jeon Sung H Cho Sang G Lim Mun‐Gyeong Kwon Jin‐Hyung Yoo 《Aquaculture Research》2013,44(10):1502-1510
Effects of various concentrations of Scutellaria baicalensis (SB) extract in diets on growth, body composition, serum chemistry and disease challenge test of far eastern catfish (Silurus asotus) were determined and compared with a commercially available immune enhancer. Eight experimental diets were prepared in triplicate: control (Con) diet without supplementation of SB and SB‐0.25, SB‐0.5, SB‐1, SB‐2, SB‐3 and SB‐5 diets containing SB at concentrations of 0.25, 0.5, 1, 2, 3 and 5%, respectively. In addition, 0.1% of a commercial immune enhancer product (CP) was also tested. No significant difference in weight gain of fish was found. Feed consumption, feed efficiency ratio and protein retention of fish were not affected by the experimental diets. At the end of the 8‐week feeding trial, 10 externally normal fish from each tank were infected by Vibrio anguillarum or Strepotococcus iniae. Cumulative mortality of fish fed the Con diet was higher than that of fish fed the all other diets in 10 and 25 days after V. anguillarum or S. iniae infection. Results of this study indicated that dietary inclusion of SB extract was effective in improving survival of eastern catfish after V. anguillarum and S. iniae infection, but the various concentrations of SB did not affect fish performance. 相似文献
976.
Jeong-Yong Cho Hyoung Jae Lee Gee An Kim Gwi Deok Kim You Seok Lee Soo Cheol Shin Keun-Hyung Park Jae-Hak Moon 《Journal of Cereal Science》2012
γ-Oryzanol (steryl ferulates; SF) has been shown to be a major bioactive compound in rice. To determine the content of individual γ-oryzanols in brown rice by high performance liquid chromatography (HPLC), purification of individual SF for use as an external standard is required. Four main SF were isolated from a commercial γ-oryzanol mixture and identified as cycloartenyl ferulate (1), 24-methylenecycloartanyl ferulate (2), campesteryl ferulate (3), and sitosteryl ferulate (4) based on mass spectrometry and nuclear magnetic resonance spectroscopic data. The SF contents between conventional and organic brown rice were qualitatively determined by HPLC using SF isolated from a commercial γ-oryzanol mixture as the external standard. The total γ-oryzanol content (mg/100 g) in organic brown rice (65.6 ± 2.7) was slightly higher (P < 0.05) than that found in conventional brown rice (60.2 ± 1.8). The content (mg/100 g) of 1 (21.2 ± 0.9) and 4 (9.8 ± 0.4) in organic brown rice was higher (P < 0.05) than that observed in conventional brown rice (1, 18.2 ± 1.1; 4, 8.5 ± 0.3). However, the content of 2 and 3 in the conventional and organic brown rice samples did not differ significantly. These results indicate that the cultivation methods do significantly alter the γ-oryzanol content for conventional and organic brown rice. 相似文献
977.
The purpose of this study was to classify various fabrics into some meaningful groups and to predict the fabrics’ acoustic characteristics using their mechanical properties. Two hundred seventeen fabrics, fifty one knitted fabrics, fifty nine woven fabrics and one hundred and seven vapor permeable water repellent fabrics, were used as test specimen. Fabric frictional sounds of the specimen were measured with a MAFN(Measuring Apparatus for Fabric Noise, Patent: No, 2001-73360). Sound Pressure Level(SPL), psychoacoustic parameters such as Loudness(z) and Sharpness(z) of the specimen were obtained by the sound quality system. KES-FB system was used for mechanical property measurements. Cluster analysis was used to classify the specimen and discriminant analysis was used to predict the clusters. Linear regression analysis was used to suggest the equations to predict the acoustic properties using mechanical properties. 相似文献
978.
Textile sound absorbents are getting more and more popular on the market as noise reduction is a major requirement for human comfort today. In this paper we focus on a new textile material for sound absorption, by investigating the acoustic characteristics of nanofibers. Through impedance tube method we measured the sound absorption coefficients of multiple layers of nanofiber webs and compared those with microfiber materials per fabric weight. We also examined the effect of layers of nanofiber webs on regularfiber knitted fabric on sound absorption. The test results showed that the sound absorption coefficients of nanofiber layers were superior that of microfiber fabrics in the frequency range 1000–4000 Hz. In this range, the sound absorption of nanofiber webs improved with numbers of layers. Also, adding nanofiber web plies to regularfiber fleece increased the sound absorption coefficient with 85 % at 4000 Hz. From our results we could observe differences in the sound absorption coefficients between two test methods, which are higher absorbance coefficients through the reverberation room method than impedance tube method. 相似文献
979.
Mei Jing Piao Yu Jae Hyun Suk Ju Cho Hee Kyoung Kang Eun Sook Yoo Young Sang Koh Nam Ho Lee Mi Hee Ko Jin Won Hyun 《Marine drugs》2012,10(12):2826-2845
The present study investigated the photoprotective properties of an ethanol extract derived from the red alga Bonnemaisonia hamifera against ultraviolet B (UVB)-induced cell damage in human HaCaT keratinocytes. The Bonnemaisonia hamifera ethanol extract (BHE) scavenged the superoxide anion generated by the xanthine/xanthine oxidase system and the hydroxyl radical generated by the Fenton reaction (FeSO4 + H2O2), both of which were detected by using electron spin resonance spectrometry. In addition, BHE exhibited scavenging activity against the 1,1-diphenyl-2-picrylhydrazyl radical and intracellular reactive oxygen species (ROS) that were induced by either hydrogen peroxide or UVB radiation. BHE reduced UVB-induced apoptosis, as shown by decreased apoptotic body formation and DNA fragmentation. BHE also attenuated DNA damage and the elevated levels of 8-isoprostane and protein carbonyls resulting from UVB-mediated oxidative stress. Furthermore, BHE absorbed electromagnetic radiation in the UVB range (280–320 nm). These results suggest that BHE protects human HaCaT keratinocytes against UVB-induced oxidative damage by scavenging ROS and absorbing UVB photons, thereby reducing injury to cellular components. 相似文献
980.
Masaaki Kiyoto Shingo Saito Kazuyuki Hattori Nam-Seok Cho Takaaki Hara Yuzo Yagi Masakazu Aoyama 《Journal of Wood Science》2008,54(2):179-181
The aqueous extract of the edible mushroom Sarcodon aspratus showed inhibitory effects against angiotensin I-converting enzyme (ACE). l-Pipecolic acid (l-piperidine-2-carboxylic acid) was isolated from a hot-water extract in a 0.02% yield as an active principle. The mode of
inhibition of l-pipecolic acid was found to be competitive, whereas its d-isomer showed no significant inhibitory effects against ACE, suggesting that the configuration of the carboxyl group in the
molecule plays an important role in the enzyme inhibition. 相似文献