“…In this context, milk industry wastes, particularly whey powder rich in lactose, would be an attractive source of substrates, which provides galactose upon hydrolysis of lactose (Zhang et al, 2020). As attempts to obtain potential source of L-AIs with a high efficiency, more than 30 L-AIs have been reported thus far from various natural or engineered microorganisms, such as Escherichia coli (Wu et al, 2020), Clostridium hylemonae (Nguyen et al, 2018), Bacillus subtilis (Kim et al, 2010), Bacillus coagulans (Mei et al, 2016), Lactobacillus plantarum (Chouayekh et al, 2007), Lactobacillus brevis (Guo et al, 2018), Geobacillus thermodenitrificans (Kim and Oh, 2005), Enterococcus faecium (Marylane et al, 2017) and Bifidobacterium longum (Salonen et al, 2012). However, almost all of these L-AIs showed higher specificity to L-arabinose than the specificity to D-Galactose (Xu et al, 2018).…”