The current mainstream segment for ginger (Zingiber officinale) is as an ingredient is for nausea and digestive, but there is emerging data on ginger’s impact on the gut microbiota and therefore its potential benefits for immune health.
Writing in the journal PharmaNutrition, Japanese scientists note: “In spite of these attractive functions, the major pungent phenolic constituents of ginger, such as 6-gingerol (6 G), 8-gingerol (8 G), 10-gingerol, and 6-shogaol (6S), exhibit poor solubility in water and low oral bioavailability, possibly resulting in the limited nutraceutical effect. To overcome these problems, solubilization technologies have been applied to dietary compounds.”
One such delivery technology is a lipid-based self-emulsifying drug delivery system (SEDDS) using krill oil to improve the absorption of a ginger extract.
Scientists from the University of Shizuoka and Japan Preventive Medical Laboratory Co., Ltd. report that the best performance was achieved using a krill oil-based SEDDS of ginger extract with glycerin, compared to polyethylene glycol (PEG), and they then used the glycerin-containing system for additional study.
In vivo data
The researchers then performed experiments in lab rats, orally administering the krill oil-based SEDDS with the ginger extract or a ginger extract delivered with medium-chain triglycerides (control). The krill oil used in the study was supplied by Japan-based Acress Co., Ltd.
The data showed that, “the relative bioavailabilities of active components of [ginger extract], 6-gingerol and 8-gingerol, in the [ginger-extract/krill oil]-treated group were ca. 8-fold higher than those of [control ginger extract]-treated group, respectively.”
Additional testing showed that krill oil-ginger extract administration protected the kidneys of the animals against damage.
Shelf-life / stability testing showed that the gingerols in the krill oil-ginger extract did not degrade over four weeks of storage at 40 °C and 40 °C/75% relative humidity. This was linked to the antioxidant components in krill oil, according to the researchers.
“The present investigation is the first attempt to apply [krill oil] as [an] excipient of SEDDS and develop [ginger extract]-loaded formulations employing [krill oil], with glycerin and PEG,” wrote the researchers.
“[Krill oil]-based SEDDS technology could enhance the dissolution and pharmacokinetic properties of active ingredients in [ginger extract], offering potent renoprotective function and other nutraceutical effects. The [krill oil]-based SEDDS approach might be available for improving the nutraceutical value of other lipophilic active ingredients, as well as [ginger extract].”
Published online ahead of print, doi: 10.1016/j.phanu.2021.100285
“Krill oil-based self-emulsifying drug delivery system to improve oral absorption and renoprotective function of ginger extract”
Authors: M. Ogino et al.