Penapisan membran adalah salah satu kaedah alternatif dalam pemekatan propolis. Kepekatan polifenol dan flavonoid yang diekstrak daripada propolis telah dilakukan dengan menggunakan mikrofiltrasi. Tiga membran yang berbeza iaitu PVDF, PTFE dan PVDF yang diubahsuai telah digunakan untuk mengkaji fluks meresap dan penolakan sebatian. Di samping itu, mekanisme penyekat liang membran telah dikaji dan dikenalpasti. Daripada keputusan yang diperolehi, ia boleh dirumuskan bahawa membran PVDF yang diubahsuai adalah yang terbaik di antara ketiga-tiga membran kerana prestasi yang boleh mencapai peratusan penolakan yang sangat tinggi untuk kandungan polifenol berjumlah 80.9% dan peratusan penolakan untuk kandungan flavonoid daripada 85.0% . Membran PVDF yang diubahsuai telah dipilih dan beberapa parameter seperti tekanan operasi, suhu operasi dan kepekatan solusi input telah dimanipulasi untuk menentukan prestasi membran PVDF yang diubah suai. Fluks meresap meningkat dengan peningkatan tekanan operasi dan untuk suhu operasi tetapi peningkatan dalam kepekatan input, mengurangkan fluks meresap. Bagi penolakan kandungan fenolik dan flavonoid, ia mengalami peningkatan apabila ada peningkatan dalam tekanan operasi dan kepekatan propolis tetapi apabila suhu meningkat, penolakan kandungan fenolik dan flavonoid berkurang.
_______________________________________________________________________________________________________
The membrane filtration is one of the alternative method in concentrating propolis. The concentration of the total polyphenol and flavonoids extracted from propolis was performed using ultrafiltration. Three different membrane which are PVDF, PTFE and modified PVDF were used to study the permeate flux and the rejection of the compounds. Besides that, the fouling mechanism of the membranes were studied and determined. From the results gained, it can be summarize that the modified PVDF membrane is the best among the three membrane because of its performance that can achieve very high rejection percentage for polyphenol content of 80.9% and rejection percentage for flavonoids content of 85.0%. The modified PVDF was selected and several parameters of operating temperature, operating temperature and feed concentration was manipulated to determine the performance of the modified PVDF membrane. Permeate flux was increased with the increased of operating pressure and operating temperature. While, the permeate flux decreased when the feed concentration of propolis increased. For the rejection of phenolic and flavonoids content, it is increase with the increase in operating pressure and concentration of propolis but ascending pattern of temperature reduce the rejection of phenolic and flavonoids content.
Concentrating propolis using microfiltration / Md Rasyidi Md Akib