Table 2 Summary on the Limitations of Current β-glucans Research

• No β-glucan control standard with specific molecular weight and branches are available. Most of the β-glucans publication used zymosan, which is a mixture of chitosan, β-glucans, and cell wall particles.

• Most of the β-glucan containing herbal research are based on extracts rather than purified β-glucans

• No well characterization methods either qualitatively or quantitatively are currently available for assessing and comparing β-glucans from different sources.

• Lack of translational approach to apply knowledge of receptor and signal pathways of β-glucan to animal studies or clinical trials.

• The exact immunological actions and signaling pathway induced by β-glucan are still unclear and have to be further defined.