ABSTRACT
Phospholipase A! is known as an effective catalyst for hydrolysis of various phospholipids in enzymatic vegetable oil degumming. Immobilization is one of the most efficient strategies to improve its activity, recovery and functional properties
In this study, chitosan-co-polyethylene oxide [90:10] nanofibrous mat was successfully fabricated and modified with atmospheric plasma at different times [2, 6 and 10 min] to interact with enzyme molecules. Scanning electron microscopy images revealed that the membranes retained uniform nanofibrous and open porous structures before and after the treatment. PLA[1] was successfully immobilized onto the membrane surfaces via covalent bonds with the functional groups of chitosan nanofibrous mat. Response surface methodology was used to optimize the immobilization conditions for reaching the maximum immobilization efficiency
Enzyme concentration, pH, and immobilization time were found to be significant key factors. Under optimum conditions [5.03 h, pH 5.63, and enzyme dosage 654.36 UI], the atmospheric plasma surface modified chitosan nanofibers reached the highest immobilization efficiency [78.50%]
Fourier transform infrared spectroscopy of the control and plasma surface-modified chitosan nanofibers revealed the functional groups of nanofibers and their reaction with the enzyme
The results indicated that surface modification by atmospheric plasma induced an increase in PLA[1] loading on the membrane surfaces
ABSTRACT
Thalassemia major and its treatment by stem cell transplantation can have deleterious effects on bone integrity. This study assesses the adverse effects of transplantation on growing bones of pediatric thalassemic patients. Bone mineral density [BMD] of 20 patients from three thalassemia classes whose mean [SD] age was 7.4 [3.8] years were tested with a Norland XR-46 device at baseline [before transplantation], 6 and 12 months after transplantation. At 6 and 12 months after transplantation we observed no significant changes in mean BMD. There were no Z-scores less than -2 among patients. Class 3 thalassemia did not negatively impact BMD. Calcium [Ca], phosphorous [P] and ferritin levels were not significantly related to patients' BMD scores. Transfusion duration and chelation therapy showed positive significant relationships to BMD [g/ cm2], but no significant relation with the BMD Z-score. The deleterious relation between corticosteroid use and changes in BMD was not significant. In contrast, patients who developed acute graft versus host disease [aGVHD] after transplantation showed significant adverse effects on BMD of their femur [P = 0.020] and spine [P = 0.027]. Stem cell transplantation in pediatric thalassemic patients who do not develop aGVHD does not appear to have any significant positive or negative effects on BMD
Subject(s)
Humans , Male , Female , beta-Thalassemia , Hematopoietic Stem Cell Transplantation/adverse effects , Pediatrics , Graft vs Host DiseaseABSTRACT
Arachidonic acid is an essential fatty acid in human nutrition. In the present study, production of arachidonic acid by Mortierella alpina CBS 754.68 was evaluated in submerged fermentation. The fermentation variables were selected in accordance with the Plackett-Burman [PB] design and further optimized via response surface methodology [RSM]. Five significant variables, namely glucose, yeast extract, temperature, agitation rate, and fermentation time were selected for the optimization studies. The statistical model was constructed via central composite design [CCD]. Following the optimization step arachidonic acid production increased by approximately 660.5%, when compared to the screening step. The results indicate that carrying out the fermentation under the conditions of glucose at 50 g/l; yeast extract at 14 g/l; temperature of 22°C; agitation rate of 180 rpm, and fermentation time of 8 days will increase the arachidonic acid production up to 3 g/l. Results show that the optimization of culture conditions could greatly increase arachidonic acid production by Mortierella alpina CBS 754.68