Abstract:

The microwave-assisted extraction of konjac glucomannan (KGM) from konjac flour was studied. The
influence of extraction parameters including extraction temperature, microwave power and solid/liquid ratio on KGM
content was examined by one-factor-at-a-time and orthogonal array design. The optimal process conditions for KGM
extraction were found to be extraction at 90 ℃ and a microwave power of 700 W for 60 min with a solid-to-liquid ratio
of 1:160. The KGM content of crude extracts under the optimized conditions was 70.75%. Temperature significantly
affected the extraction of KGM. The optimized extraction process provided a stable extraction technique which had
the advantages of high KGM content, short extraction time and high antibacterial activity of konjac flour extracts.
The superiority of the microwave-assisted extraction method has been verified by infrared and scanning electron
microscopy (SEM).

Key words: microwave-assisted extraction, konjac, konjac glucomannan