Mesenchymal stromal/stem cells (MSCs) derived from perinatal tissues have become indispensable sources for clinical applications due to their superior properties, ease of accessibility and minimal ethical concerns. MSCs isolated from different placenta (PL) and umbilical cord (UC) compartments exhibit great potential for stem cell-based therapies. However, their biological activities could vary due to tissue origins and differences in differentiation potentials. This review provides an overview of MSCs derived from various compartments of perinatal tissues, their characteristics and current isolation methods. Factors affecting the yield and purity of MSCs are also discussed as they are important to ensure consistent and unlimited supply for regenerative medicine and tissue engineering.

Abstract-Currently the resources for fossil fuels are depleting together with increase in fuel prices. This has urged the need for cheaper alternative fuels especially biofuels. The production of the most common liquid biofuel which is bioethanol using immobilized yeast cells is an approach taken to increase its demand in the world's market. There are various methods for the immobilization of yeast cells; however before they can be applied in the industry the stability of the immobilization technology must be investigated. This research aims to study the stabilities of immobilized S. cerevisiae in calcium alginate and carrageenan beads for bioethanol production. The S. cerevisiae was immobilized in calcium alginate and carrageenan beads using entrapment method. Next, screening for the optimal concentration of sodium alginate and semi refined carrageenan matrices were determined by employing fermentation and bioethanol quantification using GC-MS. Concentrations of 2% (w/v) calcium alginate and 2% (w/v) semi refined carrageenan beads were identified to produce the highest bioethanol yield which were 0.286 g/mL and 0.065 g/mL respectively. The two beads were then chosen to be tested in various stability studies with respect to bioethanol production such as storage stability, reusability, pH, thermaland permeability test. It was found out that a concentration of 2% (w/v) calcium alginate beads were more stable as immobilization matrix for S. cerevisiae as compared to 2% (w/v) semi refined carrageenan.

Background: Mesenchymal stem cells (MSCs) have a promising role in regenerative medicine with their self-renewal and multilineage differentiation abilities. However, cell expansion is essential before their application and reports have showed that long term culture of MSCs can alter their stem cell characteristics. Wharton's jelly derived MSCs (WJ-MSCs) as favorable source of MSCs need to be examined in long term culture before used in clinical settings. In this study, WJ-MSCs were isolated via enzymatic digestion using collagenase type 1. Cells at P5, P10 and P15 were observed for their morphology and growth kinetics where the findings showed that the extensive culture of WJ-MSCs can reach an average of 40 population doubling time with slight changes in their fibroblast-like morphology. The analysis of clonogenic activity showed no significant difference in WJ-MSCs' ability in forming colony at early passage and later passage. Oil Red O and Von Kossa staining results for in vitro differentiation assays of WJ-MSCs into adipocytes and osteocytes showed WJ-MSCs were easily differentiated at P5 compared to P15. The reduction in both proliferation and differentiation potentials of WJ-MSCs were observed at later passages (P15). These suggested that as the passage numbers increases cells loss the ability in maintaining their plasticity. In conclusion, long term culture of WJ-MSCs can impair their stem cell properties therefore improvement in culture method to maintain these properties is essential.