• Nattaporn Soonthornsit Department of Pharmaceutical Technology, Faculty of Pharmaceutical Sciences and Center of Excellence for Innovation in Chemistry, Naresuan University, Tha Pho, Muang Phitsanulok, Phitsanulok 65000, Thailand
  • Warinkarn Hemstapat Department of Pharmacology, Faculty of Science, Mahidol University, Rama VI Road, Ratchathewi, Bangkok 10400, Thailand
  • Chetsadaporn Pitaksutheepong Food Biotechnology Research Unit, National Center for Genetic Engineering and Biotechnology (BIOTEC), 113 Thailand Science Park, Phahonyothin Road, Khlong Nueng, Khlong Luang, Pathum Thani 12120, Thailand
  • Tasana Pitaksuteepong Department of Pharmaceutical Technology, Faculty of Pharmaceutical Sciences and Center of Excellence for Innovation in Chemistry, Naresuan University, Tha Pho, Muang Phitsanulok, Phitsanulok 65000, Thailand


Objective: This study was aimed to develop oral microemulsions and to evaluate their ability to enhance stability, release and intestinal digestion of mulberry stem extract (MSE).

Methods: The pseudoternary phase diagrams were constructed using caprylic/capric triglyceride (oil), PEG-8 caprylic/capric glycerides (S), polyglyceryl-3 diisostearate (CoS) and an aqueous phase. The effects of S/CoS (Km) ratio and a cosolvent, i.e. polyethene glycol 400 or propylene glycol (PG), were investigated. The optimized formulations were selected and incorporated with MSE. Then, they were then subjected to stability, release and lipolysis studies. The control solution consisted of 50% PG and 50% water.

Results: The formation and characteristics of the microemulsions were influenced by Km and cosolvents. The two optimized formulations (F3 and F4) consisted of 10% oil, 70% S/CoS mixture and 20% aqueous phase were chosen. The Km ratios of F3 and F4 were 4:1 and 3:1. The aqueous phase of F3 and F4 was water and water mixed with PG, respectively. These formulations could improve the stability of MSE better than the control solution. The accumulated release of MSE from F3, F4 and the control solution reached 100% while that of unformulated crude extract reached only 70% after 6 h. The lipolysis study showed that MSE incorporated in both F3 and F4 was digested more than double the percentage compared to that of MSE incorporated in the control solution.

Conclusion: MSE was successfully developed in microemulsions. They are shown to be promising vehicles for oral delivery of MSE. Further animal trials are suggested.

Keywords: Mulberry stem extract, Microemulsion, Stability, Release, In vitro intestinal digestion


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How to Cite
Soonthornsit, N., W. Hemstapat, C. Pitaksutheepong, and T. Pitaksuteepong. “ENHANCEMENT OF STABILITY, RELEASE AND IN VITRO DIGESTIBILITY OF MULBERRY STEM EXTRACT USING MICROEMULSIONS”. International Journal of Pharmacy and Pharmaceutical Sciences, Vol. 9, no. 7, July 2017, pp. 103-9, doi:10.22159/ijpps.2017v9i7.18609.
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