Fluorescence quantum yield of natural dye extracted from Tradescantia pallida purpurea as a function of the seasons: Preliminary bioapplication as a fungicide probe for necrotrophic fungi

• Published in: Journal of photochemistry and photobiology. B, Biology Vol. 200; p. 111631
• Main Authors: De Lima, Sthanley R., Felisbino, Douglas G., Lima, Manuela R.S., Chang, Roberto, Martins, Mário M., Goulart, Luiz Ricardo, Andrade, Acácio A., Messias, Djalmir N., Dos Santos, Roberto R., Juliatti, Fernando C., Pilla, Viviane
• Format: Journal Article
• Language: English
• Published: Lausanne Elsevier B.V 01.11.2019; Elsevier BV
• Subjects: Aqueous solutions; Diffraction patterns; Dyes; Fluorescence; Fluorescence quantum yield; Fungi; Fungicide; Fungicides; Leaves; Natural dye; Pesticides; Phase modulation; Quantum efficiency; Seasons; Spectroscopy; Thermal analysis; Thermal effects; Tradescantia; Tradescantia pallida; Spectroscopy; Fluorescence quantum yield; Natural dye; Fungicide; Thermal effects
• ISSN: 1011-1344; 1873-2682
• DOI: 10.1016/j.jphotobiol.2019.111631

In this work, over the course of four seasons (12 months), we have monitored the fluorescence quantum efficiency (η) from two sets (S1 and S2) of fresh natural dye extracts from the leaves of Tradescantia pallida purpurea. The natural dye was extracted in aqueous solutions from leaves collected from regions with a predominance of shade (S1) and sun (S2) during the day. The thermo-optical parameter fractional thermal load (φ) was measured using conical diffraction (CD) patterns caused by thermally driven self-phase modulation, for η determination in both sets of solutions. Fluorescence measurements corroborate the CD results, and the η values are, on average, slightly higher (~ 11%) in the summer than in the other seasons for both sets of samples (S1 and S2). In addition, the experimental results are presented using natural dye extracted from Tradescantia pallida purpurea as a fungicide probe in Fusarium solani, Sclerotinia sclerotiorum, and Colletotrichum gloeosporioides fungi. The promising fungicide results obtained for the aqueous natural dye extract were compared with those obtained for other natural dyes and fungi. The fungi tested are of the necrotrophic group and constitute important pathosystems in Brazil, causing diseases in several crops that synthetic fungicides often cannot control or do so with low efficiency. [Display omitted] •Natural dyes were extracted from the leaves of Tradescantia pallida purpurea.•The extraction was performed from leaves collected from regions with shade and sun.•The fluorescence quantum efficiency (η) was evaluated as a function of the seasons.•Fluorescence measurements corroborate the η results.•Anthocyanin extract was tested as a fungicide probe in fungi.