Phytotoxicity of alkaloids, coumarins and flavonoids isolated from 11 species belonging to the Rutaceae and Meliaceae families

Abstract

Meliaceae and Rutaceae families are known for the high diversity of their secondary metabolites, which include many groups that represent a rich source of structural diversity, and are good candidates as sources of allelochemicals that could be useful in agriculture. In the work described here the bioactivity profiles were evaluated for 3 alkaloids (1-3), 12 coumarins (4-15), 2 phenylpropanoic acid derivatives (16 and 17) and 14 flavonoids (18-31) from 11 species belonging to the Meliaceae and Rutaceae families. All compounds were tested in the wheat coleoptile bioassay and those that showed the highest activities were tested on the STS (Standard Target Species) Lepidium sativum (cress), Lactuca sativa (lettuce), Lycopersicon esculentum (tomato), and Allium cepa (onion). Most of the isolated compounds showed phytotoxic activity and graveoline (3), psoralen (8), and flavone (18) were the most active, with bioactivity levels similar to that of the commercial herbicide Logran 1. The results indicate that these compounds could be involved as semiochemicals in the allelopathic interactions of these plant species.

Recent advances in allelopathy for weed control: from knowledge to applications

“…) have been isolated from Ruta graveolens and Hortia oreadica by applying the aforementioned extraction method but with HPLC. The obtained furanocoumarins inhibited the growth of Lepidium sativum , Lycopersicon esculentum and Allium cepa , and this effect was even stronger than that of a commercial herbicide . Apiaceae species also produce furanocoumarins.…”

“…In all cases where isolation techniques have been applied to furanocoumarins, compounds were obtained from the aerial parts of plants, including fruits. Furanocoumarins are phytotoxic, antiproliferative and insecticidal …”

Alkaloid profiling of herbal drugs using high resolution mass spectrometry

“…As regards this, some alks are considered to be responsible for the beneficial effects of traditional medicines and their intake is often associated with widespread consumption of herbal infusions, used worldwide as “natural” home medical treatments. In contrast, some alks may have the harmful effects of poisons . In particular, pyrrolizidine (Pyz) alks have hepatotoxic, mutagenic, and carcinogenic effects.…”

Targeted and untargeted profiling of alkaloids in herbal extracts using online solid‐phase extraction and high‐resolution mass spectrometry (Q‐Orbitrap)

“…Moreover, in addition to fulfilling these specific functions in plants, ALKs often manifest a marked physiological action on humans and animals, acting very quickly on specific areas of their nervous system. Some of them are regarded as responsible for the beneficial effects of traditional medicines, but some may instead have the harmful effects of poisons . In particular, pyrrolizidine ALKs have hepatotoxic, mutagenic and carcinogenic effects, and in accordance with the German Federal Institute for Risk Assessment (BfR), a daily intake limit of 0.007 µg kg −1 body weight (0.42 µg for a 60‐kg adult) was established for 1,2‐unsaturated pyrrolizidine ALKs…”