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A Customizable Approach for the Enzymatic Production and Purification of Diterpenoid Natural Products
Published on: October 4, 2019
ent-Kaurene diterpenoids from Blepharispermum hirtum
Majekodunmi O Fatope1, Gouri B Varma, Nasser M Alzri
1Department of Chemistry, College of Science, Sultan Qaboos University, P. O. Box 36, Al-Khod-123, Muscat, Sultanate of Oman. majek@squ.edu.om
Chemistry & Biodiversity
|July 27, 2010
Summary
Blepharispermum hirtum extracts yielded two new ent-kaurene diterpenoids, blepharispins A and B. One compound showed significant larvicidal activity against brine shrimp nauplii, while another exhibited antimicrobial properties against bacteria.
Area of Science:
- Phytochemistry
- Natural Products Chemistry
- Pharmacology
Background:
- Blepharispermum hirtum (Asteraceae) is a plant species with potential medicinal applications.
- Investigation of its chemical constituents can reveal novel bioactive compounds.
Purpose of the Study:
- To isolate and characterize compounds from Blepharispermum hirtum twigs and leaves.
- To evaluate the larvicidal and antimicrobial activities of these compounds.
Main Methods:
- Extraction and fractionation of plant material.
- Structure elucidation using spectral data (NMR, MS).
- Bioassays including brine shrimp lethality assay (BST) and determination of minimum inhibitory concentration (MIC).
Main Results:
- Two new ent-kaurene diterpenoids, blepharispins A and B, were isolated and their structures determined.
- Compound 4 exhibited significant larvicidal activity (BST LC50 = 1.3 µg/mL).
- Blepharispins A and B showed antimicrobial activity against Staphylococcus aureus and Bacillus subtilis (MIC = 62.5 µg/mL).
Conclusions:
- Blepharispermum hirtum is a source of bioactive ent-kaurene diterpenoids.
- The isolated compounds possess notable larvicidal and antimicrobial properties.
- Findings support further research into the biosynthetic pathways and traditional uses of these compounds.
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