• Korean journal of applied entomology
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• v.34 no.2
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• pp.95-99
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• 1995

Acid phosphatase(AP) of he aphid, Megoura crassicauda and the major component of the lady beetle's artificial diet, fresh chicken liver, was adapted as a model protein to study the digestion of diet proteins in the midgut of Harmonia axyridis. The lady beetle did not secrete its own AP into the lumen of the midgut. The aphid and the live chicken liver had AP which was still alive in enzymatic activity from the extract of the lumen of the midgut of the lady beetle. The digestive ability of the lady beetle on proteins turned out to be different depending on food sources. In the lumen of the midgut of the lady beetle, though most of AP of live chicken liver lost its activity withtin 12 hours, that of M. cassicauda kept strong enzymatic activity up to 24 hours.

• Journal of Aquaculture
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• v.16 no.4
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• pp.233-239
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• 2003

Growth and activities of digestive enzymes in slime flounder (Microstomus achne) larvae were measured from hatching to near the end of larval development (day 58). Larvae reared under starved and fed conditions and the changes of acid phosphatase (ACPase) specific activity, alkaline phosphatase (ALPase) specific activity, trypsin-like enzyme activity and pepsin-like enzyme activity were described with growth and developmental stage of larvae. Total length of the starved larvae was gradually increased for 7 days post hatching and then almost unchanged. Total length of the fed larvae ranged from 5.13$\pm$0.178 mm at the day of hatching to 13.43$\pm$1.395 mm at 58 days after hatching. In starved group, dry body weight decreased from 0.l0$\pm$0.020 mg at the day of hatching to 0.05$\pm$0.012 mg at 12 days after hatching. Dry body weight of fed larvae decreased during the prelarva stage like starved group and then gradually increased. ACPase and ALPase specific activity in the starved larvae increased until all larvae died, however those activities in the fed larvae increased until 20 days and then decreased until 58 days after hatching, with no significant difference between groups. Trypsin-like enzyme activity in the starved larvae was unchanged until 3 days and then was the highest on 5 days after hatching, but not detected after completion of yolksac absorption. Those of fed larvae decreased until 3 days and sharply increased until completion of yolksac absorption. The highest trypsin-like enzyme activity in the fed group was observed at 20 days after hatching. Trypsin-like enzyme activity in the fed larvae was significantly higher than that in the starved larvae from 8 days after hatching. Pepsin-like enzyme activity was increased in 5 days after hatching in both groups. There was significant difference at 8 and 10 days after hatching between both groups. Based on above results, digestive enzyme activities were correspondingly changed to a growth and morphological transformation. Trypsin-like enzyme and pepsin-like enzyme activities are able to be a useful indices for health and growth status in larval slime flounder, because there was significant difference in digestive enzyme activities with developmental stages, growth or feed supply.

• Journal of Aquaculture
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• v.22 no.1
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• pp.105-111
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• 2009

In this study, we carried out an experiment for estimation the larval digestibility in aspects which digestive enzymatic activities and nutrition of the rotifers, Brachionus rotundiformis. Thus we enhanced the digestive enzymatic activity through the addition of starch for the increase of digestibility of rotifer (starch-rotifer), and compared with the feed efficiency through rearing of the olive flounder, Paralichthys olivaceus used rotifer lipid-enriched with Algamac $2000^{(R)}$ (CE-rotifer). The digestive enzyme activities (except for TG-lipase), total protein contents, total essential amino acid, essential amino acids (methionin and phenylalanine) of starch-rotifer (the rotifer used a starch as additive, and enriched not) was assayed significantly higher than CE-rotifer (P<0.05). And total lipid, lipid classes (except for sterol) and fatty acids as DHA and EPA showed higher in CE-rotifer than starch-rotifer (P<0.05). But, sterol contents and ST/TG ratio were shown significantly higher in starch-rotifer (P<0.05). The flounder larvae supplied the two rotifers showed standard length and body weight that not significantly differed with ranges $3.72{\sim}3.79\;mm$ and $32.9{\sim}37.8\;mg$/larva on 6 days after hatching (DAH), respectively (P>0.05). However, these of 12 DAH showed the values of significantly higher to $5.94{\pm}0.249\;mm$, $144.0{\pm}23.86\;mg$/larva and $26.2{\pm}12.13%$ in standard length, body weight and survival in CE-flounder than that of starch-flounder (P<0.05). The hydrolytic enzymatic activities of flounder larvae severally supplied the two rotifers showed the significantly higher activities in acidic -amylase, neutral -amylase, TG-lipase, lysozyme and acidic phosphatase in starch-flounder on 5 DAH (P<0.05). But neutral $\alpha$-amylase, three proteases and two phosphatases of CE-flounder on 11 DAH showed the significantly higher activities than that of starch-flounder (P<0.05). Therefore, for the flounder, Paralichthys olivaceus larvae just depleted yolk was more beneficial to supply the feed, rotifer, enhanced the digestibility than to supply the feed lipid-enriched for aspect of larval digestibility up to 6 DAH, thereafter nutrition of absorption due to the development of digestive organs suggested that enrichment effect appeared with larval somatic growth. Consequently, investigation more detailed about the larval digestive physiological and nutritional requirement variations after 6 DAH will be necessary, thereafter.

• Proceedings of the Ginseng society Conference
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• 1988.08a
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• pp.63-69
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• 1988

The effect of $ginsenoside-Rb_2$ purified from ginseng was examined in rats with streptozotocin-induced diabetes. The rats of the $ginsenoside-Rb_2-treated$ group showed a significant decrease in blood glucose level as well as a significant decrease of glucose-6-phosphatase in the liver. whereas a significants rise was observed in the activity of glucokinase. Furthermore, the rats treated with $ginsenoside-Rb_2$ showed a significant decrease of glucose and a slight increase of glycogen in the hepatic tissue. The glucose-6-phosphate level tended to increase, the pyruvate level was unchanged and the lactate level tended to decrease. There was, however. no accumulation of total lipid in hepatic tissue. The serum levels of triglyceride. non-esterified fatty acid. 3-hydroxybutyrate and acetoacetate were markedly decreased, showing a trend toward restoration of the normal state and inducing. an increase in lipids in the adipose tissue. Additional experiments involving long-term administration of $ginsenoside-Rb_2$ produced results suggesting that $ginsenoside-Rb_2$ may improve diabetic symptoms such as overeating, overdrinking. polyuria and glycosuria.