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1.
São Paulo; s.n; s.n; 2020. 236 p. tab, graf.
Thesis in Portuguese | LILACS | ID: biblio-1290815

ABSTRACT

Os aminoácidos tipo micosporinas (MAAs) são compostos, produzidos por algumas espécies de cianobactérias e outros microorganismos, principalmente quando são expostos a radiação ultravioleta (UVR). Estes compostos, que vêm demonstrando funções fotoprotetoras e antioxidantes, têm sido pesquisados para aplicação em protetores solares e em produtos antienvelhecimento. O presente estudo focou na caracterização de cianobactérias e outros organismos quanto à produção de MAAs com potencial aplicação em cosméticos. Neste estudo foram desenvolvidos diversos métodos para identificação (via HPLC-DAD-MS/HRMS), purificação (via HPLC-DAD) e quantificação de MAAs (via LC-MS/MS). Pelo método de identificação de MAAs verificou-se que, das 75 cianobactérias estudadas, 27 cepas (38%) sintetizam MAAs. A cepa Oscilatoria sp. CMMA 1600 produziu a maior diversidade de MAAs. 10 MAAs diferentes foram identificados incluindo um MAA de massa molecular 316 Da. Através de dados espectroscópicos obtidos via HPLC-DAD-HRMS e RMN 1D e 2D confirmou-se que se tratava da micosporina-glicina-alanina. A biossíntese natural deste composto por cianobactérias foi relatada pela primeira vez neste estudo. Quanto à quantificação de MAAs, o protocolo de extração otimizado possibilitou uma excelente recuperação dos compostos de interesse, além de ser bastante simples e não utilizar solventes poluentes. As análises via LC-MS/MS foram realizadas através de experimentos de MRM em modo positivo usando uma coluna de fase reversa. O método validado permitiu determinar e quantificar com precisão os MAAs porphyra-334, shinorina e micosporina-glicina-alanina em corridas de apenas 6 minutos, com limites de deteção inferiores a 0,005 µg.mg -1. Aplicando o método de LC-MS/MS realizaram experimentos de indução de MAAs através de exposição à UVR tendo-se observado um aumento da concentração de MAAs nas cepas que já sintetizam estes compostos e, outras cepas começaram a produzir pelo menos um MAA. As cepas de S. torques-reginae (ITEP-024 e ITEP-026) produziram a maior concentração de MAAs. A cepa ITEP-024 foi ainda exposta a diferentes radiações tendo-se observado que a UVB é que mais influencia a produção de MAAs. Neste estudo foi demonstrado o potencial das cianobactérias como produtores de MAAs que podem ser utilizados como fotoprotores em protetores solares


Mycosporines and mycosporine-like amino acids (MAAs) are UV-absorbing compounds produced by cyanobacteria and other organisms, especially upon exposer to solar ultraviolet radiation (UVR). These compounds are photoprotective and some have additional antioxidant functíons useful to the natural cosmetics market. This study aims to identify MAAs-producing cyanobacteria with potential applicatíons in cosmetics. A HPLC-DAD-MS/HRMS method for the identification of MAAs was developed. Out of the 75 cyanobacteria studied, 27 strains (38%) synthesized MAAs. Oscilatoria sp. CMMA 1600, from homocyte type, produced the greatest diversity of MAAs. 10 different MAAs were identified including a MAA with molecular weight of 316 Da. The chemical structure of mycosporine-glycine-alanine was confirmed by 1D/2D NMR and HRMS analyses. This compound has never been reported from a natural source. In this study, a validated LC-MS/MS quantification method for MAAs is also presented. An easy-to-handle and rapid extraction procedure was developed which uses only water and volatile additives as the extractor solvents. The LC-MS/MS method was performed using multiple reaction monitoring in positive mode with a reverse-phase column. The method enabled the accurate determination and quantification of the MAAs porphyra-334, shinorine and mycosporine-glycine-alanine in a 6 minutes running time, with limits of detection < 0.005 µg.mg-1. MAAs induction experiments were performed through UVR exposure. MAAs are constitutively produced by some cyanobacteria and production was further enhanced following UVirradiance. Other strains start to produce at least one MAA after UV-irradiance. Sphaerospermopsis torques-reginae strain (ITEP-024 and ITEP-026) produced the highest concentration of these photoprotective compounds. S. torques-reginae ITEP 024 strain was further exposed to different radiation compositíons. MAAs were significantly influenced by UVB. In this study, the potential of cyanobacteria as MAA producers, that can be used as photoprotectors in sunscreens, has been demonstrated


Subject(s)
Health Strategies , Cyanobacteria/classification , Cosmetics/classification , Amino Acids/analysis , Ultraviolet Rays , Pharmaceutical Preparations , Validation Study
2.
Rev. bras. farmacogn ; 21(2): 202-208, mar.-abr. 2011. ilus, graf, tab
Article in English | LILACS | ID: lil-590179

ABSTRACT

Qualitative and quantitative studies of mycosporine-like amino acids (MAAs) in three species of the genus Gracilaria Greville (G. birdiae, G. domingensis and G. tenuistipitata) were performed. A simple and efficient extraction procedure based on ethanol was described. HPLC, UV and mass spectrometry experiments revealed different profiles between extracts obtained from one species cultivated in the laboratory (G. tenuistipitata) and two species collected in their natural environment (G. birdiae and G. domingensis). The levels detected in the latter two species were approximately 150 times higher than in the species cultivated in vitro. This study revealed that G. birdiae and G. domingensis present a potential source for economical exploration of MAAs.

3.
Article in Chinese | WPRIM | ID: wpr-589593

ABSTRACT

Objective To study on bioactive chemical compounds against ultraviolet irradiation in antarctic ice microalgae.Methods Four kinds of Antarctic ice microalgae were cultured under the conditions of low temperature,illumination,UV-A and UV-B irradiation.The chemical compounds were extracted by methanol and analyzed by spectrophotometer and HPLC/MS.The molecular structures were elucidated according to these data.The chemical compounds were irradated by sunshine to observe the speed of degradation and to estimate the bioactivity.Results There were five active compounds in Chlorophyceae L-4 and 7 active compounds in Diatom HF-9,in which 6 compounds belong to MAAs(mycosporine-like amino acids) and were of more bioactivity against ultraviolet irradiation.Conclusion MAAs from of Antarctic ice microalgae play an important role in resisting ultraviolet irradiation.

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