Ascorbic acid (ASC) was assayed on deproteinized extracts. An aliquot
of each VYLB was mixed with 6% (wt/v) TCA, incubated on ice
for 15 min and centrifuged (15,600×g for 10 min, 4 °C). The supernatants
were collected for analysis of vitamin C according to the method
described by Degl'Innocenti et al. (2005).