Catalyzes the hydrolysis of sulfoquinovosyl diacylglycerides (SQDG) to sulfoquinovose (SQ), which is then degraded by E.coli through the SQ Embden-Meyerhof-Parnas (SQ-EMP) sulfoglycolysis pathway as a source of carbon and sulfur. Therefore, is likely involved in the utilization of the sulfoquinovose headgroup found in ubiquitous plant sulfolipids. Is also able to hydrolyze simple sulfoquinovosides such as 1-sulfoquinovosylglycerol (SQGro). Is a retaining glycoside hydrolase, since it forms the alpha anomer of SQ (PubMed:26878550). Also exhibits some alpha-glucosidase activity against alpha-glucosyl fluoride in vitro, although natural substrates, such as alpha-glucobioses are scarcely hydrolyzed (PubMed:15294295). a 6-sulfo-alpha-D-quinovosyldiacylglycerol + H2O = 6-sulfo-alpha-D-quinovose + a 1,2-diacyl-sn-glycerol Is inactivated in vitro by the mechanism-based inactivator 5-fluoro-beta-L-idopyranosyl fluoride (5FIdoF) that yields a covalent glycosyl-enzyme complex with the active site nucleophile Asp-405. kcat is 14.3 sec(-1) with para-nitrophenyl alpha-sulfoquinovoside as substrate. Optimum pH is 6. Glycolipid metabolism. Induced during growth with sulfoquinovose. Belongs to the glycosyl hydrolase 31 family.