Process development and characterization of sporopollenin exine capsules (SECs) from cattail pollen grains
Bok, Chuan Kiat
Date of Issue2016
Exine capsules from natural pollen grains are widely explored as novel biomaterials for various biomedical and drug delivery applications. In order to make suitable for encapsulation, these pollen grains need to process to remove all pollen constituents effectively. These microcapsules extracted from pollen grains are almost identical in size, morphology for a given plant species and are readily obtainable in large bulk quantities with different sizes in micron size range. At present, cattail pollen is consumed by human as bio-supplements ingredient, food (cattail pancakes) and as Traditional Chinese Medicine (TCM). In TCM term, cattail pollen is also known as “Pu Huang”  and is widely used to treat hemorrhagic conditions. Hematuria (Blood discharge from the anus), Metrorrhagia and erythrocyturia have been treated with oral Cattail pollen since long ago. Cattail pollen also served as a hemostyptic agent to treat cuts on the skin surface. In addition, studies have also identified immunosuppressive activity , cytotoxicity against cancer cells , antiatherogenic effects  and an ability to reduce atherosclerotic plaque , making cattail pollen a good source for encapsulation study. Its sporopollenin can be extracted via acetolysis  or enzymatic hydrolysis method . These capsules can be obtained after several reagents processing to remove protoplasmic contents of plant pollen grains and used to readily microencapsulate a wide range of materials with better encapsulation efficiency, release profile and permeability. The past research studies only focused on extraction of cattail sporopollenin but did not indicate any optimization process or optimized results for extraction. This report will cover the optimal chemical process for extraction of intact and clean sporopollenin (SP) capsules from cattail pollen (Typha Angustifolia). The chemical process was designed to be scalable and time efficient. The inner cellular content removal at different stages of processing was confirmed by CHN elemental analysis, scanning electron microscopy (SEM) and Dynamic Imaging Particle Analysis (DIPA) analysis. Clean, intact SECs are obtained after lipid extraction treatment of cattail pollen with hot acetone (45°C), 2.5 hours of acidolysis with the use of 85% (v/v) phosphoric acid, and suspension in 10% Polyethylene Glycol (PEG) solution.
Final Year Project (FYP)
Nanyang Technological University