In this anti-wrinkle study, the researchers used a 0.5% solution of beta glucan and claim to see some results.
In truth, once you start mixing in a bunch of different ingredients like glycols, sodium PCA, or other anti-aging materials, it all starts to become redundant making most of your ingredients superfluous.
If you want to highlight beta glucan as your star ingredient, make it your star ingredient. Don’t add a bunch of other things that will simply compete with the effectiveness of the material.
Of course, if your goal is to make the best performing product, then I would suggest a different approach.