• Journal of the Korea Academia-Industrial cooperation Society
• /
• v.12 no.1
• /
• pp.276-280
• /
• 2011

This study investigated the activation conditions of pancreatic enzymes from porcine pancreas. Duodenum induced the activation of pancreatic protease and lipase in pancreas. When 10% duodenum was added to pancreatic juice and the mixture was incubated at $30^{\circ}C$ for 90 min or at $25^{\circ}C$ for 4 hrs, the activities of pancreatic protese and lipase reached the peak. When the pancreatin was prepared by sequential process of enzymatic activation at $25^{\circ}C$ for 4 hrs, centrifugation, acetone precipitation and freeze-drying, the specific activities of pancreatic protease, lipase and amylase were 136, 116 and 400 U/mg-protein, respectively. The protease, lipase and amylase activities of the prepared pancreatin were 5.4, 58.0 and 16.0 times higher than those of USP standard, respectively.

• Journal of Microbiology
• /
• v.39 no.4
• /
• pp.305-313
• /
• 2001

The spr D gene encoding Strptomyces griseus protease D(SGPD); a chymotrypsin-like proteae, was cloned from Strptomyces griseus IFO13350 and sequence. Most of the amino-acid sequence deduced from the nucleotide sequence is idential to that Strptomyces griseus IMRU3499 except that one amino acid has been deleted and Trp 369 has been substituted into Cys369 in the SGPD from S. griseus IFO13350 without affecting the protease activity. The spr D gene was overexpressed in Streptomyce liv-idans TK24 as a heterologous host. Various media with different compositions were also used to max-imize the productivity of SGPD inthe heterologous host. The SGPD productivity was best when the transformant S. lividans TK24 was cultivated in R2YE medium. The relative chymotrypsin activity of the culture broth measured with an artificial chromogenic substrate, N-scuccinyl-ala-ala-pro-phe-p-nitroanilide, was 16 units/ml. A high level of SGPD was also produced in YEME and SAAM medial but it was relatively lower that in R2YE medium and negligible amounts of SGPD were produced in GYE, GAE and Benedict media. The growth of S. lividans reacted the maximum level of cell mass at days 3 and 4 of the culture, but SGPD production started in the stationary phase of cell growth and kept increase in till the 10$^{th}$ day of culture in R2YE and YEME medium, but in GYE media the productivity reached maximum level at 8days of cultivation. The introduction of the spr D gene into S. lividans TK24 triggered biosyntheis of the pigmented antibiotic , actinorhodin, which implies some protease may paly a very improtant role in secondary-metabolite formation in sStreptomyces.

• The Journal of Advanced Prosthodontics
• /
• v.16 no.2
• /
• pp.126-138
• /
• 2024

PURPOSE. The aim of this study was to evaluate the influence of different 3D dental resins, using a manufacturer recommended printer and a third-party printer, on cellular responses of human gingival cells. MATERIALS AND METHODS. Three NextDent resins (Denture 3D+, C&B MFH and Crowntec) were used to produce specimens on printers NextDent 5100 (groups ND, NC and NT, respectively) and Phrozen Sonic Mini 4K (groups PD, PC and PT, respectively). Human gingival fibroblasts were cultured and biocompatibility was evaluated on days 1, 3 and 7. IL-6 and IL-8 concentrations were evaluated at 3 days using ELISA. Surface roughness was evaluated by a contact profilometer. SEM and fluorescence micrographs were analyzed at days 1 and 7. Statistical analyses were performed using SPSS and mean differences were tested using ANOVA and post-hoc Tukey tests (P < .05). RESULTS. There was an increase in cellular viability after 7 days in groups PC and PT, when compared to group PD. ND group resulted in higher concentration of IL-6 when compared to PT group. SEM and fluorescence micrographs showed less adhesion and thinner morphology of fibroblasts from group PD. No significant differences were found regarding surface roughness. CONCLUSION. The use of different printers or resins did not seem to influence surface roughness. NextDent 5100 and Phrozen Sonic Mini 4K produced resins with similar cellular responses in human gingival fibroblasts. However, Denture 3D+ resin resulted in significantly lower biocompatibility, when compared to C&B MFH and Crowntec resins. Further testing is required to support its long-term use, required for complete dentures.