Site Specific Delivery of Microencapsulated Fish Oil to the Gastrointestinal Tract of the Rat

Abstract

The aim of this study was to design food grade matrices to deliver microencapsulated fish oil to the large bowel of the rat where the potential exists to retard inflammation and cancer development. Digestion in simulated gastric fluid and intestinal fluid demonstrated that only 4-6% of oil was released from the following dried emulsion formulations: 50% fish oil encapsulated in heated casein-glucose-dried glucose syrup (1:1:1) (Cas-Glu-DGS-50); 25% fish oil in casein-modified resistant starch (Hylon VII) (1:1) (Cas-Hylon-25); or 25% fish oil in Cas-Glu-Hylon (1:1:1) (Cas-Glu-Hylon-25). A short-term gavage study (0-12 h) with fish oil and Cas-Glu-DGS-50 demonstrated the appearance of fish oil long chain (LC) n-3 polyunsaturated fatty acids (PUFA) into the plasma indicating specific small intestinal absorption with little LC n-3 PUFA reaching the large bowel. In a 2-week-long term, daily gavage study, the bioavailability of fish oil and fish oil in Cas-Glu-DGS-50 or Cas-Hylon-25 demonstrated that fish oil and Cas-Glu-DGS-50 LC n-3 PUFA were incorporated into the tissue of the small intestine and colon, whereas Cas-Hylon-25 was resistant to degradation in the small intestine. The use of modified Hylon VII for targeted colonic delivery was confirmed in the final short-term gavage study (0-14 h) using Cas-Glu-Hylon-25 with [(14)C]-trilinolenin as a marker incorporated into the microcapsules, where up to 60% of the labeled oil reached the large bowel. Depending on the microencapsulating matrix employed, fish oil can be delivered selectively to the small intestine or to a high degree to the large bowel.

Effects of microencapsulation on the gastrointestinal transit and tissue distribution of a bioactive mixture of fish oil, tributyrin and resveratrol

“…A previous study showed that fish oil emulsions were significantly protected against lipolysis in the upper GI tract when stabilized by a heated matrix of protein, sugar and modified resistant starch (Patten, Augustin, Sanguansri, Head, & Abeywardena, 2009). This apparent discrepancy may be related to some notable differences between the studies.…”

“…In the present study a mixture of fish oil, tributyrin and resveratrol was used in the microencapsulated formulation, the rats were fasted for 9.5-14.5 h prior to dosing and were not fed after dosing (except in the case of the 24 h time point group where food was re-introduced at 8.5-10.5 h after dosing to avoid unacceptably prolonged fasting) and the unencapsulated bioactive mixture was administered in water (after vigorous vortexing to disperse the oil) prior to gavaging. However, in the previous study (Patten et al, 2009) there was only fish oil in the microencapsulated preparation, the rats were fasted for 24 h prior to dosing, rats were allowed food after dosing and the unencapsulated fish oil was gavaged as neat oil. The presence of food in the stomach at the time of gavaging appears to afford more protection to the encapsulated bioactives.…”

“…This may be because the food and digested food components can interact with the microencapsulated formulation and provide an additional barrier against early release of the encapsulated bioactives. Therefore in any gut transit and absorption study, the amount of gavaged material and the formulation of the introduced matrix and particle size are important from the point of accelerated gastric emptying together with the level of fasting (Chaudhuri & Fink, 1990;Hodges, Carr, Hazzard, O'Reilly, & Carr, 1995;Lentle & Jannsen, 2008;Lentle & Jannsen, 2010;Patten et al, 2009). …”

Factors affecting lipase digestibility of emulsified lipids using an in vitro digestion model: Proposal for a standardised pH-stat method

“…This knowledge is being used by the pharmaceutical industry to develop lipid-based delivery systems that deliver drugs to specific locations within the GI tract (Porter & Wasan, 2008;Pouton, 2006). Similar systems are now being developed by the food industry to encapsulate, protect and deliver bioactive food components (McClements, Decker, Park, & Weiss, 2007;McClements et al, 2009;Patten, Augustin, Sanguansri, Head, & Abeywardena, 2009;Singh et al, 2009). Many of these delivery systems are being designed to modulate the digestion and release of bioactive food components within the GI tract.…”

Microencapsulation of Fish Oil Using Hydroxypropyl Methylcellulose As a Carrier Material by Spray Drying

“…The in vitro digestion has been carried out in two phases: first, the encapsulated oil has been exposed to simulated gastric fluid (SGF) containing pepsin and sodium chloride at low pH value (Chung et al 2011), and second, an intestinal digestion was simulated by exposing gastric digestion elements to a simulated intestinal fluid (SIF) (Patten et al 2009). …”