L.J. Yin, H.H. Lee, J.J. Wu, S.T. Jiang
noni hydrolysates, probiotics, functionality, cellulase
This study aimed to help the release of functional nutrients from noni fruit by enzymatic hydrolysis, and to subsequently shorten the fermentation time during the biotransformation of some compounds. This study firstly investigated the optimal amount of cellulases (0, 25, 50, 75, 100, and 125 U/mL) using in hydrolysis at 50oC for 10 h (noni: water=1:4) and then screened the probiotic strains in fermented at 37oC for 24 h. The enzymatic hydrolysis was employed to process noni, which can subsequently shorten the fermentation time and possibly utilize these cellulases hydrolyzed noni puree by probiotic. The reducing sugars increased from 3.86, 3.53, 2.77, and 4.25 mg/mL to 50.12, 44.63, 36.42, 45.23 mg/mL (calibrated by glucose, galactose, arabinose and fructose), while the total phenolic compounds and flavonoids contents also increased from 80.43 and 24.72 to 92.03 and 41.85 μg/g, respectively, after 8 h hydrolysis with 75 U/mL cellulase at 50oC. The reducing power and ABTS˙+ scavenging ability also increased from 139.24 and 42.32 to 164.12 ppm and 88.99%, respectively. However, the noni puree and its hydrolysate could not be used as media for the lactic acid bacteria tested except for Pediococcus pentosaceus BCRC 14053 (data not shown). Therefore, the resulted hydrolysate was further fermented by Pediococcus pentosaceus BCRC 14053 with the addition of 10% glucose and 0.2% CaCO3, the LAB counts increased to 7.09 log CFU/mL, while the pH decreased to 4.93 after 24 h cultivation. These data suggested that noni hydrolystaes could be utilized by Pediococcus pentosaceus BCRC 14053.