Antifungal effects The antifungal activity of chitosan was discovered already in 1979 [175], and has been utilized to inhibit fungal growth in crops [176]. The antifungal potential of CHOS has to a lesser extent been investigated. In 1984 Kendra and Hadwiger [177] tested the antifungal activity of monomers–heptamers of deacetylated CHOS on Fusarium solani, which is infectious to pea crops, and found that the heptamer was most effective. Subsequent research has revealed that longer oligomers of CHOS (also called low molecular weight chitosan, LMWC) are more effective. LMWC (4.6 kDa, average DP of 23) shows antifungal activity against Candida krusei and inhibits spore germination in Fusarium oxysporum [178]. Seyfarth et al. [26] found antifungal effects of LMWC on different Candida species. Both DP and FA of the chitosan/CHOS are of great importance for the antifungal potential and LMWC with low FA so far seems to be the most promising type of compound [179]. The anti-fungal effect of LMWC seems to be caused by its interaction with lipids in the plasma membrane, leading to morphological changes and cell surface disruptions [180,181]. The composition of the fungal plasma-membrane seems to be important for the sensitivity against chitosan, and a higher content of polyunsaturated fatty acids makes the fungi more sensitive [182]. From literature studies, as well as from own unpublished work on non-medical use of LMWC as anti-fungals, it is clear that LMWC indeed have a considerable potential in this area. This is a good reason for giving the application of LMWC, to combat fungal infections in humans, more research attention than it has received so far.