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Compuestos degradados de lignina identificados en madera silicificada de hace 200 millones de años
Science (New York, N.Y.)
|June 2, 1978
Resumen
Compuestos antiguos de lignina, degradados durante 200 millones de años, fueron encontrados en madera silicificada del Triásico. La pirólisis reveló que estas antiguas moléculas orgánicas son similares a los productos modernos de descomposición de la lignina.
Área de la Ciencia:
- La paleobotánica es la paleobotánica.
- La geoquímica orgánica es la geoquímica orgánica.
- Geocronología Geocronología.
Sus antecedentes:
- La madera silicificada del período Triásico ofrece una visión de los ecosistemas antiguos.
- La lignina es un polímero complejo que se encuentra en las paredes celulares de las plantas, crucial para comprender la evolución y la descomposición de las plantas.
Objetivo del estudio:
- Para identificar compuestos de lignina degradados en la madera silicificada del Triásico.
- Para comparar los productos de pirólisis de la lignina antigua con los de la lignina moderna.
Principales métodos:
- Análisis de muestras de carbono negro de madera silicificada mediante pirólisis.
- Cromatografía de gases y espectrometría de masas (GC-MS) para identificar los productos de pirólisis.
Principales resultados:
- Se identificaron compuestos degradados de lignina en madera silicificada de 200 millones de años de antigüedad.
- La pirólisis produjo dióxido de carbono, alcanos, alquenos, derivados del benceno, fenoles, indenes, benzofuranos y naftalenos.
- Estos pirolizados coinciden con los de la lignina moderna cuando se calientan por encima de 500 ° C.
Conclusiones:
- La lignina puede conservar su firma química durante escalas de tiempo geológicas.
- El estudio proporciona evidencia de la estabilidad a largo plazo de la materia orgánica derivada de la lignina en la madera silicificada.
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