ReviewPublished 12 October 2026Recombinant bacterial β -galactosidases for lactose bioconversion and galacto-oligosaccharide production: a comparative overviewAnel Kostanova · Yuliya Shamsiyeva · Zhiger Akishev · Bekbolat Khassenov · Annelya TursunbekovaFrontiers in Microbiologydoi 10.3389/fmicb.2026.1943869