ABSTRACT
The last decade has seen that increased focus was placed on studies of the bioavailability of these compounds in order to better understand the said functions in vivo. Unfortunately, much of the early bioavailability (and function) data were generated using the aglycone forms of avonoids, with attention paid to glycosylated and metabolite forms only recently. The vast majority of avonoids exist in plants as O-or C-glycosylated, acylated, or prenylated and sometimes sulfated derivatives, which give rise to more than 6000 forms of these compounds.3 To compound matters, while neuroprotective effects have been observed for many avonoids in vitro,4 neuroprotection in animal studies has either not been forthcoming or been only achieved using particular delivery mechanisms.5
