Abstract Species richness in tropical forests is correlated with other dimensions of diversity, including the diversity of plant–herbivore interactions and the phytochemical diversity that influences those interactions. Understanding the complexity of plant chemistry and the importance of phytochemical diversity for plant–insect interactions and overall forest richness has been enhanced significantly by the application of metabolomics to natural systems. The present work used proton nuclear magnetic resonance spectroscopy (1H‐NMR) profiling of crude leaf extracts to study phytochemical similarity and diversity amongPiperplants growing naturally in the Atlantic Rainforest of Brazil. Spectral profile similarity and chemical diversity were quantified to examine the relationship between metrics of phytochemical diversity, specialist and generalist herbivory, and understory plant richness. Herbivory increased with understory species richness, while generalist herbivory increased and specialist herbivory decreased with the diversity ofPiperleaf material available. Specialist herbivory increased when conspecific host plants were more spectroscopically dissimilar. Spectral similarity was lower among individuals of common species, and they were also more spectrally diverse, indicating phytochemical diversity is beneficial to plants. Canopy openness and soil nutrients also influenced chemistry and herbivory. The complex relationships uncovered in this study add information to our growing understanding of the importance of phytochemical diversity for plant–insect interactions and tropical plant species richness.
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Phyllobilins – Bioactive Natural Products Derived from Chlorophyll – Plant Origins, Structures, Absorption Spectra, and Biomedical Properties
Abstract Phyllobilins are open-chain products of the biological degradation of chlorophyll a in higher plants. Recent studies reveal that phyllobilins exert anti-oxidative and anti-inflammatory properties, as well as activities against cancer cells, that contribute to the human health benefits of numerous plants. In general, phyllobilins have been overlooked in phytochemical analyses, and – more importantly – in the analyses of medicinal plant extracts. Nevertheless, over the past three decades, > 70 phyllobilins have been identified upon examination of more than 30 plant species. Eight distinct chromophoric classes of phyllobilins are known: phyllolumibilins (PluBs), phylloleucobilins (PleBs), phylloxanthobilins (PxBs), and phylloroseobilins (PrBs)–each in type-I or type-II groups. Here, we present a database of absorption and fluorescence spectra that has been compiled of 73 phyllobilins to facilitate identification in phytochemical analyses. The spectra are provided in digital form and can be viewed and downloaded at www.photochemcad.com. The present review describes the plant origin, molecular structure, and absorption and fluorescence features of the 73 phyllobilins, along with an overview of key medicinal properties. The review should provide an enabling tool for the community for the straightforward identification of phyllobilins in plant extracts, and the foundation for deeper understanding of these ubiquitous but underexamined plant-derived micronutrients for human health.
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- Award ID(s):
- 2054497
- PAR ID:
- 10520392
- Publisher / Repository:
- Thieme
- Date Published:
- Journal Name:
- Planta Medica
- Volume:
- 89
- Issue:
- 06
- ISSN:
- 0032-0943
- Page Range / eLocation ID:
- 637 to 662
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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