Abstract: Useful polysaccharides, such as &bgr;-1,3-glucans, from a biological raw material can be solubilised and/or isolated by treating the raw material with an oxidising agent that leads to oxidation of primary hydroxyl groups in the glucan. The oxidising agent is preferably a catalytic amount of a nitroxyl compound in the presence of a re-oxidising agent such as hypochlorite or an oxidative enzyme with oxygen or hydrogen peroxide. The polysaccharide retains its useful properties during this treatment and is, moreover, more readily available. If desired, protein material from the raw material can also be utilised.

Abstract: The present invention relates to the use of an active compound including a sphingoid base, a derivative of a sphingoid base, a salt of a sphingoid base, a ceramide or a mixture of two or more of these compounds for manufacturing a composition for topical application for inhibiting mammalian ceramidase activity in the skin and microbial ceramidase originating from micro-organisms present on the skin. The composition may further contain an amount of a compound capable of complexating divalent cations.