High‐Throughput Extraction of Insoluble‐Bound Ferulic Acid In Maize

Ferulic acid is a hydroxycinnamic acid that possesses positive health benefits and plays a role in both pathogen and insect resistance in maize (Zea mays L.). Many protocols for the extraction of insoluble‐bound ferulic acid in maize use methods that are low‐throughput and are not conducive to analyzing the large number of samples used in field research or breeding programs. We examined two protocols for the extraction of insoluble‐bound ferulic acid that use small sample sizes typical of experiments where a large number of samples need to be analyzed. The main distinguishing feature between the two protocols is the inclusion of a starch digestion step in Protocol A to inhibit the swelling of intact starch when introduced to an alkali reagent. Our results indicate that the inclusion of a starch digestion step during the extraction of insoluble‐bound ferulic acid from maize is necessary if small sample sizes are used. The omission of the starch digestion step in Protocol B resulted in an average percent recovery of only 79.0% of the insoluble‐bound ferulic acid. Conversely, the inclusion of the starch digestion step in Protocol A allowed for the accurate and high‐throughput extraction of insoluble‐bound ferulic acid at lower cost than Protocol B.