In vitro antitumor activities of the lichen compounds olivetoric, physodic and psoromic acid in rat neuron and glioblastoma cells

Figures & data

Table 1. ¹H NMR and ¹³C NMR spectral data of OLA.

Position	δH (ppm)	δC (ppm)
1	–	166.95
2	–	110.52
3	–	150.23
4	7.23	118.48
5	–	156.64
6	6.96	111.92
7	2.65	39.32
8	1.61	33.92
9	1.32	34.48
10	1.35	25.74
11	0.93	17.15
12	–	174.42
13	–	108.93
14	–	168.29
15	6.18	104.92
16	–	166.87
17	6.71	115.71
18	–	144.23
19	3.46	50.19
20	–	211.16
21	2.42	45.26
22	1.55	26.29
23	1.32	34.36
24	1.35	25.41
25	0.93	17.15

Table 2. ¹H NMR and ¹³C NMR spectral data of PHA.

Position	δH (ppm)	δC (ppm)
1	6.94	108.14
2	–	164.42
3	–	110.78
4	–	142.16
5	–	143.91
6	–	150.12
7	–	177.23
8	2.65	30.61
9	1.61	33.28
10	1.32	33.44
11	1.35	24.78
12	0.93	16.22
13	–	162.74
14	–	116.16
15	–	162.58
16	6.66	102.26
17	–	164.19
18	6.86	115.29
19	–	141.59
20	3.46	50.16
21	–	209.32
22	2.42	44.26
23	1.56	25.29
24	1.32	33.35
25	1.35	24.46
26	0.93	16.22

Table 3. ¹H NMR and ¹³C NMR spectral data of PSA.

Position	δH (ppm)	δC (ppm)
1	–	155.35
2	7.05	118.27
3	–	167.12
4	–	113.56
5	–	169.57
6	–	115.15
7	–	195.16
8	2.49	25.12
9	–	163.78
10	–	145.74
11	–	145.32
12	–	132.78
13	7.53	110.74
14	–	157.56
15	–	125.58
16	2.19	9.75
17	–	169.32
18	3.84	58.18

Figure 1. The chemical structures of lichen secondary metabolites: (a) olivetoric acid, (b) physodic acid and (c) psoromic acid.

Figure 2. Viability rate in cells exposed to different lichen secondary metabolites (a) for PRCC cells (b) for U87MG cells. Each value is expressed as mean ± standard deviation (n = 3).

Table 4. IC₅₀ values for PRCC cells exposed to different lichen secondary metabolites (mg/L).

Metabolite	IC50 (limits)	Slope ± standard error (limits)	X^2
Olivetoric acid	125.71^b (67.35–384.96)	0.53 ± 0.08 (0.37–0.69)	7.67
Physodic acid	698.19^c (271.52–3925.03)	0.72 ± 0.11 (0.50–0.94)	3.51
Psoromic acid	79.40^a (54.15–139.73)	0.80 ± 0.09 (0.63–0.97)	8.14

Values followed by different superscript letters in the same column differ significantly at p < 0.05.

Table 5. IC₅₀ values for U87MG cells exposed to different lichen secondary metabolites (mg/L).

Metabolite	IC50 (limits)	Slope ± standard error (limits)	X^2
Olivetoric acid	17.55^a (14.67–21.67)	0.89 ± 0.08 (0.73–1.05)	3.49
Physodic acid	410.72^c (182.89–1704.22)	0.67 ± 0.10 (0.48–0.86)	2.17
Psoromic acid	56.22^b (44.13–77.32)	1.16 ± 0.10 (0.98–1.35)	13.33

Values followed by different superscript letters in the same column differ significantly at p < 0.05.

Figure 3. LDH release level in cells exposed to different lichen secondary metabolites (a) for PRCC cells and (b) for U87MG cells. Each value is expressed as mean ± standard deviation (n=3). Values followed by different small letters differ significantly at p<0.05.

Figure 4. TAC levels of different lichen secondary metabolites on cells (a) for PRCC cells and (b) for U87MG cells. Each value is expressed as mean ± standard deviation (n=3). Values followed by different small letters differ significantly at p<0.05.

Figure 5. TOS levels of different lichen secondary metabolites on cells (a) for PRCC cells and (b) for U87MG cells. Each value is expressed as mean ± standard deviation (n=3). Values followed by different small letters differ significantly at p<0.05.

Figure 6. 8-OH-dG level in cells exposed to different lichen secondary metabolites (a) for PRCC cells and (b) for U87MG cells. Each value is expressed as mean ± standard deviation (n=3). Values followed by different small letters differ significantly at p<0.05.

Table 6. Correlation between different variables for PRCC cells exposed to OLA.

	Cell viability	Concentration	LDH activity	Oxidative DNA damage	TAC	TOS
Cell viability	1.00^a	−0.90**	−0.88**	−0.85**	0.37	−0.78**
Concentration	−0.90**	1.00	0.91**	0.95**	−0.70**	0.94**
LDH activity	−0.88**	0.91**	1.00	0.97**	−0.51	0.85**
Oxidative DNA damage	−0.85**	0.95**	0.97**	1.00	−0.64*	0.92**
TAC	0.37	−0.70**	−0.51	−0.64*	1.00	−0.79**
TOS	−0.78**	0.94**	0.85**	0.92**	−0.79**	1.00

^a Pearson correlation coefficient.

* Correlation is significant at the 0.05 level.

** Correlation is significant at the 0.01 level.

Table 7. Correlation between different variables for U87MG cells exposed to OLA.

	Cell viability	Concentration	LDH activity	Oxidative DNA damage	TAC	TOS
Cell viability	1.00^a	−0.92**	−0.97**	−0.98**	0.48	−0.95**
Concentration	−0.92**	1.00	0.98**	0.85**	−0.59*	0.95**
LDH activity	−0.97**	0.98**	1.00	0.93**	−0.54*	0.97**
Oxidative DNA damage	−0.98**	0.85**	0.93**	1.00	−0.45	0.93**
TAC	0.48	−0.59*	−0.54*	−0.45	1.00	−0.63*
TOS	−0.95**	0.95**	0.97**	0.93**	−0.63*	1.00

^a Pearson correlation coefficient.

* Correlation is significant at the 0.05 level.

** Correlation is significant at the 0.01 level.

Table 8. Correlation between different variables for PRCC cells exposed to PHA.

	Cell viability	Concentration	LDH activity	Oxidative DNA damage	TAC	TOS
Cell viability	1.00^a	−0.97**	−0.98**	−0.96**	−0.90**	−0.40
Concentration	−0.97**	1.00	0.97**	0.95**	0.89**	0.50
LDH activity	−0.98**	0.97**	1.00	0.98**	0.92**	0.32
Oxidative DNA damage	−0.96**	0.95**	0.98**	1.00	0.94**	0.28
TAC	−0.90**	0.89**	0.92**	0.94**	1.00	0.22
TOS	−0.40	0.50	0.32	0.28	0.22	1.00

^a Pearson correlation coefficient.

** Correlation is significant at the 0.01 level.

Table 9. Correlation between different variables for U87MG cells exposed to PHA.

	Cell viability	Concentration	LDH activity	Oxidative DNA damage	TAC	TOS
Cell viability	1.00^a	−0.97**	−0.97**	−0.93**	0.38	0.42
Concentration	−0.97**	1.00	0.95**	0.89**	−0.42	−0.32
LDH activity	−0.97**	0.95**	1.00	0.97**	−0.28	−0.55*
Oxidative DNA damage	−0.93**	0.89**	0.97**	1.00	−0.18	−0.56*
TAC	0.38	−0.42	−0.28	−0.18	1.00	−0.02
TOS	0.42	−0.32	−0.55*	−0.56*	−0.02	1.00

^a Pearson correlation coefficient.

* Correlation is significant at the 0.05 level.

** Correlation is significant at the 0.01 level.

Table 10. Correlation between different variables for PRCC cells exposed to PSA.

	Cell viability	Concentration	LDH activity	Oxidative DNA damage	TAC	TOS
Cell viability	1.00^a	−0.90**	−0.91**	−0.94**	−0.95**	−0.02
Concentration	−0.90**	1.00	0.99**	0.97**	0.94**	0.30
LDH activity	−0.91**	0.99**	1.00	0.97**	0.95**	0.27
Oxidative DNA damage	−0.94**	0.97**	0.97**	1.00	0.97**	0.25
TAC	−0.95**	0.94**	0.95**	0.97**	1.00	0.20
TOS	−0.02	0.30	0.27	0.25	0.20	1.00

^a Pearson correlation coefficient.

** Correlation is significant at the 0.01 level.

Table 11. Correlation between different variables for U87MG cells exposed to PSA.

	Cell viability	Concentration	LDH activity	Oxidative DNA damage	TAC	TOS
Cell viability	1.00^a	−0.94**	−0.96**	−0.93**	−0.93**	0.30
Concentration	−0.94**	1.00	0.99**	0.99**	0.93**	−0.34
LDH activity	−0.96**	0.99**	1.00	0.99**	0.95**	−0.35
Oxidative DNA damage	−0.93**	0.99**	0.99**	1.00	0.92**	−0.33
TAC	−0.93**	0.93**	0.95**	0.92**	1.00	−0.45
TOS	0.30	−0.34	−0.35	−0.33	−0.45	1.00

^a Pearson correlation coefficient.

** Correlation is significant at the 0.01 level.