 หัวเรื่อง:ไม่มีชื่อไทย (ชื่ออังกฤษ : Chitobiase, Proteinase, Glycogen and some Trace Elements during Molting Cycle of Mud Crab (Scylla serrata Forsk?l 1775)) ผู้เขียน: ดร.จินตนา สและน้อย, รองศาสตราจารย์ ,  Jitlada Bootpugdeethum, ดร.มิ่งขวัญ มิ่งเมือง, รองศาสตราจารย์ , นางอมรา ทองปาน, รองศาสตราจารย์ สื่อสิ่งพิมพ์:pdf AbstractActivity profiles of chitobiase, proteinase and the content of glycogen and trace elements in gill, integument and haemolymph of mud crab (Scylla serrata) during molting cycle were determined. Chitobiase activity was at the highest level of 0.5467?0.0136 ?mol min-1mg protein-1 at 1-week premolt (D2) in gill and at 0.1413?0.0026 ?mol min-1 mg protein-1 in integument but reached the maximum level of 0.0851?0.0123 ?mol min-1mg protein-1 at 24-h postmolt (A2.2) in haemolymph. The high activities of proteinase, on the other hand, were found to be 0.6511 ? 0.0934 units mg protein-1 at 7-day postmolt (B2.3), 0.1553 ? 0.0419 units mg protein-1 at 1-week premolt (D2), and 0.1827?0.0110 units mg protein-1 at 12-h postmolt (A2.1) in gill, integument and haemolymph, respectively. These two enzymes are needed for carapace degradation as well as for chitin synthesis in preparation for carapace formation. For glycogen content, high accumulation of glycogen in the integument was observed throughout the molting cycle except at intermolt (C). In gill, however, the level of glycogen was high only before molting began (D2) while glycogen content in hepatopancreas and muscle, energy reserve tissues, was rather fluctuated but reached the maximum levels at 24-h postmolt (A2.2). As for trace elements, copper, a major component of hemocyanin, was found at high level at intermolt stage (C) in all tissues while magnesium, involving both nerve conduction and muscle contraction, showed the highest content at 7-day postmolt (B2.3) and 1-week premolt (D2) in integument and haemolymph, respectively. On the other hand, zinc showed high content at premolt stage in haemolymph and early postmolt stage in gill supporting its function in calcification. The results confirmed the roles of chitobiase, proteinase, glycogen, and trace elements which corresponded well with molting stages and physiological changes of mud crab. |
หัวเรื่อง:ไม่มีชื่อไทย (ชื่ออังกฤษ : Variation of Calcium, N-acetylglucosamine, Glucosamine and Glucose Content during Molting Cycle of Mud Crab (Scylla serrata Forsk?l 1775)) ผู้เขียน:ดร.จินตนา สและน้อย, รองศาสตราจารย์, Jitlada Bootpugdeethum, ดร.มิ่งขวัญ มิ่งเมือง, รองศาสตราจารย์, นางอมรา ทองปาน, รองศาสตราจารย์ สื่อสิ่งพิมพ์:pdf AbstractCalcium, N-acetylglucosamine, glucosamine and glucose content in the tissues of mud crab (Scylla serrata Forsk?l 1775) during molting cycle were determined. The results showed that calcium in gill decreased gradually from intermolt (C) to the lowest level of 6,527 ppm at 2-day premolt (D3) and increased again from 6-h postmolt (A1) to the highest level of 24,058.50 ppm at 7-day postmolt (B2.3) which was similar in pattern to calcium in the integument but of which at lower range (1,360.10-8,044.30 ppm). The highest content in haemolymph was found at 2-day premolt (D3). Variation of Nacetylglucosamine, a major component of chitin, showed similar pattern to calcium. Their content in gill and integument decreased from intermolt (C) to premolt (D1-D3) and increased at postmolt stages (A1-B2.3) while the pattern was opposite to that found in haemolymph which increased at premolt (D1- D3) and decreased at postmolt stages (A1-B2.3). For glucosamine, however, the content was quite low in both gill and integument but was moderately high at late postmolt in haemolymph. Glucose, on the other hand, seemed to be quite stable throughout the molting cycle (averaged 0.8973 ? 0.1489 % mg) in integument, but the profiles in hepatopancreas and gill were similar having the highest level at 5-day postmolt (B2.2). Glucose in muscle was at its peak of 0.7265 ? 0.1016 % mg at 2-day premolt (D3) followed by the ten times high level in haemolymph of 12.2020 ? 0.4807 % mg at late postmolt (B2.1). Variations of calcium, N-acetylglucosamine, glucosamine and glucose content corresponded to the changing of chemical composition of the tissues during chitin degradation of the old shed, chitin biosynthesis, mineralization of the new structure and the transportation of these substances between tissues. |