E cytotoxicity (EC50 = 250 /mL) independent from irradiation was observed for the Mdivi-1 supplier extracts of C. callisteus, C. venetus, C. traganus, and C. trivialis. An extract from the root of Berberis ilicifolia containing the all-natural photosensitizer berberine was utilized as a good handle. This extract showed an activity in the low /mL variety (e.g., EC50,A549,irr = 17 /mL) [7] against cells of the chosen cell line. In the next step, the extracts of C. xanthophyllus and C. rubrophyllus have been selected for any extra Orexin A MedChemExpress Detailed photobiological evaluation. As shown in Figure 3B, the C. xanthophyllus extract was characterized by quite higher photocytotoxicity on all 3 cancer cell lines (EC50,A549,irr = 3.7 5.3 /mL (S.I.A549 = ten.two), EC50,AGS,irr = four.six 4.five /mL (S.I.AGS = 8.1), EC50,T24,irr = 1.5 1.four /mL (S.I.T24 = 25.three)) with excellent selectivity indices. Therefore, the concentration with the extract capable of killing 50 of T24 cancer cells in the presence of blue light was more than 25 occasions decrease (i.e., additional efficient) than the concentration displaying exactly the same effect inside the dark. The C. rubrophyllus extract exhibited a light-induced amplification of cytotoxicity around the tested cell lines (EC50,A549,irr = 11.1 six.eight /mL (S.I.A549 = two.6), EC50,AGS,irr = ten.1 six.three /mL (S.I.AGS = 2.9), EC50,T24,irr = 6.1 two.1 /mL (S.I.T24 = three.7)), but additionally showed a cytotoxic effect in the absence of light. Microscopical investigations (SI Figures S4 6) recommended cell death via apoptotic processes as cells treated using the extracts of C. rubrophyllus or C. xanthophyllus in combination with blue light irradiation had been shrunken, nuclei have been condensed, and apoptotic bodies have been present [34]. Inspired by the promising green light activity of C. xanthophyllus and C. rubrophyllus in the DMA assay, the decision was created to test the photocytotoxic effect of these two extracts below green light irradiation ( = 519 33 nm). Green light, as in comparison to blue light, makes it possible for for deeper tissue penetration and lower photocytotoxic side-effects (i.e., side-effects induced by the photoactivation of riboflavin-like pigments occurring in the skin) [35]. In a preliminary experiment with the C. xanthophyllus extract, two irradiation instances (i.e., tirr = 7.0 and 15.0 min) have been compared. As anticipated, an irradiation time of tirr = 15.0 min (20.1 J cm-2) resulted in reduced EC50 values paired with larger selectivity indices (refer to SI Section two.2.1 for detailed information).Metabolites 2021, 11, 791 Metabolites 2021, 11, x FOR PEER REVIEW6 of 20 7 ofFigure 3. (Photo)cytotoxic activity of of the fungal extracts against the cancer cell lines A549, AGS, and T24 thethe presence Figure three. (Photo)cytotoxic activity the fungal extracts against the cancer cell lines A549, AGS, and T24 in in presence (BL/blue light, = 468 nm, 9.three J cm-2) and inside the absence of of blue light (D/dark). Bars: 50 50 value in /mL with (BL/blue light, = 468 2727 nm, 9.3 J cm-2) and in the absence blue light (D/dark). Bars: ECECvalue in /mL with thethe respective self-confidence interval (95). (A) Results of six extracts measured as as biological duplicates given as EC50 ranges respective self-confidence interval (95). (A) Outcomes of all all six extracts measured biological duplicates provided as EC50 ranges ( 0.01 /mL, ( . . …. 0.01 /mL,. … 55 /mL, o … .250 /mL). (B) Detailed investigation ofof probably the most promising extracts . . 55 /mL, o . . 250 /mL). (B) Detailed investigation one of the most promising extracts (i.e., C.C. xanthophyllus and C. rubrophyllus) measured.