Effect of Some Technological Factors of Extraction on Total Lentinan Content in Sapa Shiitake Mushroom Extract

In Vietnam, the source of shiitake mushroom is very abundant and grown in many provinces/cities, the total yield reaches hundreds of thousands of tons/per year, mainly serving the demand of domestic food processing, and did not develop into medicinal mushrooms yet. Among them, Sapa shiitake mushroom is being widely cultivated in Sapa-Vietnam, and is a raw material with great potential for lentinan exploitation. Until now, researches on extracting and obtaining lentinan in Vietnam are still limited. Those are reasons to carry out this research. The effects of solvent in combination with assistance of ultrasound wave in lentinan extracting capability in Sapa shiitake mushroom were studied. Before carrying out extracting of lentinan; The dried fruit bodies of Sapa shiitake mushroom was crushed in to 1mm. Five extracting parameters include concentration of Na0H solvent (%), proportion of Na0H solvent and raw material (v-w), extracting temperature, ultrasound time and ultrasound intensity were carried out. An extraction without the use of ultrasound for 180 min was control sample. Total lentinan content was obtained during the extracting process. The results indicated that shiitake mushrooms were extracted by using 0.35% Na0H solvent, the rate of Na0H solvent and mushrooms was 12-1 (v-w), intensity of ultrasound was 58 W/cm2, frequency was 20 kHz, extracting temperature was 65 °C, time of extraction was 6 min gave total lentinan content 1.63 times higher than the control.