3,6-anhydro-L-galactose 3,6-anhydro-l-galactose Bacteroides plebeius BpGH117 Caulerpa racemosa Medicine SWE Ulva lactuca additives agarose agarotriose algae anti-colon cancer activity anti-inflammation anti-obesity anti-steatosis bioactive peptides bioactives biomedical cosmetics cyanobacteria dermocosmetics exo-acting 3,6-anhydro-α-(1,3)-L-galactosidase extraction health benefits health risks human gut bacterium industrial application ingredients marine ingredients