Antibiofilm Activity of Essential Fatty Acids Against Candida albicans from Vulvovaginal Candidiasis and Bloodstream Infections

Figures & data

Figure 1 Chemical structure of EFAs. (A) ALA, α-linolenic acid. (B) EPA, eicosapentaenoic acid. (C) DHA, docosahexaenoic acid. (D) LOA, linoleic acid. (E) GLA, γ-linolenic acid. (F) AA, arachidonic acid.

Figure 2 The biofilm formation ability of C. albicans strains from vulvovaginal candidiasis (VVC) and candidemia.

Figure 3 Distribution of the minimum inhibitory concentrations (MICs) of fluconazole among C. albicans strains from vulvovaginal candidiasis (VVC) and candidemia.

Table 1 The MICs, MBICs, and MBECs of Fluconazole Against C. albicans Strains

C. albicans Strains	Source	MIC (μg/mL)	MBIC (μg/mL)	MBEC (μg/mL)
Y02	Vaginal specimen	0.25	1	128
Y20	Vaginal specimen	2	2	128
Y26	Vaginal specimen	1	4	256
Y37	Vaginal specimen	0.25	1	256
Y38	Vaginal specimen	0.5	0.5	> 256
Y65	Vaginal specimen	8	8	> 256
Y70	Vaginal specimen	1	1	> 256
X06	Blood culture	0.5	0.5	128
X09	Blood culture	0.25	0.25	64
X52	Blood culture	1	1	> 256
X54	Blood culture	2	2	256
X55	Blood culture	0.25	0.25	256

Abbreviations: MIC, minimum inhibitory concentration; MBIC, minimum biofilm inhibitory concentration; MBEC, minimum biofilm eradication concentration.

Figure 4 Inhibitory effect of essential fatty acids (EFAs) on biofilm formation of C. albicans. (A) 0.01 mM EFAs. (B) 0.1 mM EFAs. (C) 1 mM EFAs. The values shown are means ± standard deviations. An asterisk denotes a statistically significant difference compared to the untreated control (P < 0.05).

Figure 5 Eradication effect of essential fatty acids (EFAs) on mature biofilm of C. albicans. (A) 0.01 mM EFAs. (B) 0.1 mM EFAs. (C) 1 mM EFAs. The values shown are means ± standard deviations. An asterisk denotes a statistically significant difference compared to the untreated control (P < 0.05).

Table 2 The MICs of Fluconazole in Combination with EFAs Against C. albicans Strains

Strains	MIC (μg/mL)
	FLU	FLU+ALA	FLU+EPA	FLU+DHA	FLU+LOA	FLU+GLA	FLU+AA
Y02	0.25	0.5	1	1	1	0.25	1
Y20	2	8	8	8	16	8	8
Y26	1	1	1	1	1	1	1
Y37	0.25	0.5	0.5	0.5	0.5	0.5	1
Y38	0.5	2	2	2	2	1	2
Y65	8	8	8	8	8	8	8
Y70	1	2	4	4	2	2	4
X06	0.5	2	2	2	4	1	2
X09	0.25	1	1	1	1	0.5	1
X52	1	4	4	4	4	2	4
X54	2	8	8	8	8	4	8
X55	0.25	1	1	1	1	0.5	1
P-value	-	0.005	0.005	0.005	0.005	0.007	0.005

Abbreviations: MIC, minimum inhibitory concentration; FLU, fluconazole; ALA, α-linolenic acid; EPA, eicosapentaenoic acid; DHA, docosahexaenoic acid; LOA, linoleic acid; GLA, γ-linolenic acid; AA, arachidonic acid.

Table 3 The MBICs of Fluconazole in Combination with EFAs Against C. albicans Strains

Strains	MBIC (μg/mL)
	FLU	FLU+ALA	FLU+EPA	FLU+DHA	FLU+LOA	FLU+GLA	FLU+AA
Y02	1	2	4	4	4	2	4
Y20	2	2	2	2	1	2	4
Y26	4	2	<0.125	<0.125	<0.125	4	<0.125
Y37	1	2	2	2	0.5	1	2
Y38	0.5	0.5	<0.125	<0.125	<0.125	0.5	<0.125
Y65	8	8	<0.125	<0.125	<0.125	8	<0.125
Y70	1	2	2	<0.125	0.125	1	2
X06	0.5	2	<0.125	<0.125	<0.125	1	0.125
X09	0.25	0.5	0.5	0.5	0.25	0.5	1
X52	1	2	<0.125	<0.125	<0.125	1	0.125
X54	2	4	<0.125	<0.125	0.125	2	0.125
X55	1	2	4	4	4	2	4
P-value	-	0.094	0.533	0.247	0.075	0.066	1.000

Abbreviations: MBIC, minimum biofilm inhibitory concentration; FLU, fluconazole; ALA, α-linolenic acid; EPA, eicosapentaenoic acid; DHA, docosahexaenoic acid; LOA, linoleic acid; GLA, γ-linolenic acid; AA, arachidonic acid.

Table 4 The MBECs of Fluconazole in Combination with EFAs Against C. albicans Strains

Strains	MBEC (μg/mL)
	FLU	FLU+ALA	FLU+EPA	FLU+DHA	FLU+LOA	FLU+GLA	FLU+AA
Y02	128	64	16	8	8	8	8
Y20	128	128	128	128	128	128	128
Y26	256	256	256	256	256	256	256
Y37	256	64	128	256	128	64	64
Y38	> 256	> 256	> 256	> 256	> 256	> 256	> 256
Y65	> 256	> 256	> 256	> 256	> 256	> 256	> 256
Y70	> 256	> 256	> 256	256	> 256	> 256	> 256
X06	128	128	128	128	128	128	128
X09	64	8	32	64	8	8	8
X52	> 256	> 256	> 256	> 256	> 256	> 256	> 256
X54	256	256	256	256	256	256	256
X55	256	256	256	64	32	256	256
P-value	-	0.109	0.109	0.109	0.068	0.109	0.109

Abbreviations: MBEC, minimum biofilm eradication concentration; FLU, fluconazole; ALA, α-linolenic acid; EPA, eicosapentaenoic acid; DHA, docosahexaenoic acid; LOA, linoleic acid; GLA, γ-linolenic acid; AA, arachidonic acid.

Figure 6 Growth curves of C. albicans strains in the absence (control) or the presence of different concentrations of essential fatty acids (EFAs). (A–C) C. albicans Y26, (D–F) C. albicans Y38, (G–I) C. albicans Y65, and (J–L) C. albicans X52. The McF values were determined every hour during 14 h.