An efficient mammalian cell system for producing bioproducts should retain high cell viability and efficient use of energy sources rendering the need to understand the effects of various variables on the cell system. In this study, global metabolite (metabolomics) analysis approach was used to try and understand the relationships between types of media used, culture growth behavior and productivity. CHO-KI cells producing IGF-1 were obtained from ATCC and grown in T-flask (37 °C, 5 % CO2) until 70-80 % confluent in RPMI 1640 and Ham's F12, respectively. Samples were taken at 8-hourly intervals for routine cell counting, biochemical responses, insulin like growth factor-1 (IGF-1) protein concentration and global metabolite analysis (gas chromatography mass spectrometry, GCMS). Conditioned media from each time point were spun down before injection into GCMS. Data from GCMS were then transferred to SIMCA-P + Version 12 for chemometric evaluation using principal component analysis. The results showed that while routine analysis gave only subtle differences between the media, global metabolite analysis was able to clearly separate the culture based on growth media with growth phases as confounding factor. Different types of media also appeared to affect IGF-1 production. Asparagine was found to be indicative of healthiness of cells and production of high IGF-1. Meanwhile identification of ornithine and lysine in death phase was found to be associated with apoptosis and oversupplied nutrient respectively. Using the biomarkers revealed in the study, several bioprocessing strategies including medium improvement and in-time downstream processing can be potentially implemented to achieve efficient CHO culture system.

Background: A short-term study was carried out using guinea pigs to determine the effects of Curcuma domestica on lipid composition in the serum and aorta.

A panel of six monoclonal antibodies (mAbs) against the nucleocapsid (NP) protein of Newcastle disease virus (NDV) was produced by immunization of Balb/c mice with purified recombinant NP protein. Western Blot analysis showed that all the mAbs recognized linearized NP epitopes. Three different NP antigenic sites were identified using deleted truncated NP mutants purified from Escherichia coli. One of the antigenic sites was located at the C-terminal end (residues 441 to 489) of the NP protein. Two other antigenic sites were located within the N-terminal end (residues 26-121 and 122-375). This study demonstrates that the N- and C-terminal ends of the NP proteins are responsible in eliciting immune response, thus it is most likely that these ends are exposed on the NP.

Cell rupture is one of the earlier steps in downstream processing which are required for the recovery of biological products that are located inside cells. Cells could be disrupted either by using chemicals or mechanical method. In this study, cell rupture was carried out by mechanical force using high pressure homogenizer (HPH). The aim of this study is to identify optimal conditions of HPH to disrupt the cell wall of recombinant Escherichia coli harboring nucleocapsid (NP) gene of Newcastle disease virus (NDV). The optimized conditions were achieved by manipulating the independent variables of HPH such as pressure, pump speed and number of cycles through an optimization process. The efficiency of the cell disruption was determined by estimating the percentage of cell rupture as well as the amount of NP protein released from the cell lysis. Through the means plot analysis of Minitab Software (Version 14.12), pressure was recognized as the main factor for achieving the highest cell rupture and the release of NP protein. The optimized conditions for obtaining the highest NP protein yield were by operating three cycles of cell rupture, homogenizer pressure of 800 bars and pump speed of 7 psi.