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Compensatory growth of juvenile olive flounder, Paralichthys olivaceus L., and changes in proximate composition and body condition indexes of fish during fasting and after refeeding were investigated during the summer season. Groups of 25 fish each (initial body weight of 16 g) were randomly distributed into fifteen 180-L flow-through tanks. Fish were fed the experimental diet containing crude protein 46.9% and crude lipid 8.0% with estimated energy level of 14.6 kJ/g diet for 6 d/wk. Five treatments in triplicate were prepared for this study: C, S1, S2, S3, and S4. Fish in the control group (C) were hand-fed to apparent satiation twice daily. Fish in treatments S1, S2, S3, and S4 experienced 1, 2, 3, and 4 wk of starvation and were then hand-fed to apparent satiation twice daily during the remaining 7, 6, 5, and 4 wk of the experiment, respectively. A group of starved fish in the similar size was stocked and fasted throughout the 8-wk feeding trial for chemical and blood analysis. The feeding trial lasted for 8 wk. Weight of fish linearly decreased with week of starvation (P , 0.0001). Linear relationship between condition factor (CF) and hepatosomatic index (HSI) against week of starvation was observed in the starved group of fish. Survival was not significantly (P . 0.05) affected by feeding strategy. However, weight gain and specific growth rate (SGR) of olive flounder in C, S1, and S2 were significantly (P , 0.05) higher than those of fish in S3 and S4. The poorest weight gain and specific growth rate (SGR) were obtained in fish of S4. Feed consumption of olive flounder in C, S1, and S2 was significantly (P , 0.05) higher than that of fish in S3 and S4. Feed efficiency, protein efficiency ratio, and protein retention of olive flounder in C and S1 were not significantly (P . 0.05) different from those of fish in S2 but significantly (P , 0.05) higher than those of fish in S3 and S4. Hematocrit, CF, and HSI of olive flounder were not significantly (P . 0.05) affected by feeding strategy. Chemical composition of fish was not significantly (P . 0.05) affected by feeding strategy. In considering these results, it can be concluded that juvenile olive flounder have the ability to fully compensate for 2-wk feed deprivation during the summer season. Besides, feed efficiency in fish fed for 7 and 6 wk after 1-and 2-wk feed deprivation was comparable to that in fish fed for 8 wk.

This study was performed to determine the effect of the dietary inclusion of various sources of green tea on growth, body composition and blood chemistry of the olive flounder. Twenty-five juvenile fish were distributed into each of 15 180 l flow-through tanks. Five experimental diets with triplicates were prepared: control, raw leaves, dry leaves, by-product and extract. The 5% various sources (raw leaves, dry leaves and by-product) of green tea were included in the experimental diets at the expense of 5% wheat flour. The extract was diluted with water and mixed with the ingredients to maintain 5% green tea at the same concentration as in the other diets. Weight gain and specific growth rate of fish fed the control diet and experimental diet containing extract were higher than those of fish fed the diets containing raw and dry leaves and by-product. Feed and protein efficiency ratio for fish fed the control diet and diet containing extract was higher than for fish fed the diets containing raw leaves and by-product. The level of low-density lipoprotein (LDL) cholesterol of fish fed the control diet was higher than that of fish fed the other diets containing various sources of green tea. The glutamic oxaloacetic transaminase (GPT) concentration of fish fed the diets containing raw leaves and extract was lower than that of fish fed the control diet. Crude lipid content of liver in fish fed the control diet was higher than that in fish fed the diets containing raw and dry leaves and by-product but was not significantly different from that of fish fed the diet containing extract. Dietary inclusion of extract was the most effective way to improve growth and feed utilization of the olive flounder among the various sources of green tea, and all sources of green tea were effective in lowering serum LDL cholesterol and GPT of the fish.

Compensatory growth of red sea bream, Pagrus major, during feed deprivation and after refeeding was investigated. Groups of three fish each were allocated into 28 cages. Fish were fed by a commercial feed to satiation twice a day. Four feeding groups of fish were prepared: one group with continuous feeding (C) for 9 wk and three other groups with feed deprivation for 1 wk (F1) in Week 3, 2 wk (F2) from Week 2 to Week 3, and 3 wk (F3) from Week 1 to Week 3, respectively. All fish in the feed deprivation treatments resumed feeding in Week 4. The full compensatory growth was achieved in F1 and F2 fish after refeeding for the first 3 wk but in F3 fish after refeeding for the second 3 wk. Specific growth rate and feed conversion efficiency in all fish experiencing fasting were higher than those of control fish after first 3 wk of refeeding. At the end of feed deprivation in Week 3, crude protein, crude lipid, and energy content of all fish experiencing fasting were lower than those of the control fish. These results indicated that red sea bream experienced 1‐, 2‐, and 3‐wk fasting could achieve full compensatory growth in the 9‐wk feeding trial.

We have presented a biological and eco-friendly method for the synthesis of gold nanoparticles from gold precursor (HAuCl4) using Sapindus mukorossi Gaertn. fruit pericarp (soapnut shells). We investigate the production of gold nanoparticles as a function of the concentration of HAuCl4 and the amount of soapnut shells. Average nanoparticle sizes of 9, 17, and 19 nm were obtained by using the HAuCl4 concentrations of 1, 5, and 10 mM, respectively, with a fixed amount of soapnut shells extract. The resulted gold nanoparticles are highly crystalline face-centered cubic (fcc) structures. FT–IR analysis suggests that the obtained gold nanoparticles might be stabilized through the interactions of carboxylic groups in the saponins and the carbonyl groups in the flavonoids present in the soapnut shells. These soapnut shells mediated gold nanoparticles were demonstrated to have good catalytic activity for the chemical reduction of p-nitroaniline.