13 ফলাফল
Pyrethrin I, pyrethrin II, cinerin I, cinerin II, jasmolin I and jasmolin II are six closely related insecticidal active esters, known as pyrethrins, found in the pyrethrum extract from the dry flowers of Tanacetum cinerariifolium. The chemical structures of the six compounds differ only in the
Pyrethrum is a natural insecticide extracted from Tanacetum cinerariifolium. Six esters, the pyrethrins, are responsible for the extract's insecticidal activity. The oxidative degradation of pyrethrins through contact with aerial oxygen is a potential cause of pyrethrin losses during pyrethrum
Pyrethrum (Tanacetum cinerariifolium) produces insecticidal compounds known as pyrethrins. Pyrethrins are esters; the acid moiety is either trans-chrysanthemic acid or pyrethric acid and the alcohol moiety of pyrethrins is either pyrethrolone, cinerolone, or jasmolone. It was generally accepted that
Dalmatian pyrethrum (Tanacetum cinerariifolium (TREVIR.) SCH.BIP.) is a plant species endemic to the east Adriatic coast. The bioactive substance of Dalmatian pyrethrum is a natural insecticide, pyrethrin, a mixture of six active components (pyrethrins I and II, cinerins I and II, and jasmolins I
A preparative supercritical fluid extraction system is described and was used with supercritical carbon dioxide to extract the active insecticide components pyrethrin I (PI) and pyrethrin II (PII) successfully from pyrethrum flower. A high-performance liquid chromatography method was developed and
A robust analytical methodology is developed for the quantitative determination of all six insecticidal components of pyrethrum extract: jasmolin I, cinerin I, pyrethrin I, jasmolin II, cinerin II, and pyrethrin II. This method, based on the separation technique normal-phase high-performance liquid
Prolonged storage of harvested Tasmanian pyrethrum crop from Tanacetum cinerariaefolium has resulted in substantial losses of the pyrethrin esters due to the environmental conditions in the storage shed. The generation of heat, the presence of moisture and oxygen, and the microbial activity were
Bioassay-directed fractionation of the organic extract of the Kenyan pyrethrum flowers (Chrysanthemum cinerariaefolium Vissiani) resulted in the isolation of two natural pyrethrin esters, pyrethrin I (PI) and pyrethrin II (PII) as the major constituents. These esters elicited inhibition of the
Residues of pyrethrin-I (Py-I) and pyrethrin-II (Py-II), the major insecticidal components of the pyrethrum daisy (Tanacetum cinerariifolium) as well as residues of piperonyl butoxide (PBO, a pyrethrum synergist) were determined in soil and on potato foliage grown under field conditions. A pyrethrum
Pyrethrum extract is a natural insecticide that has been used worldwide for centuries, with pyrethrins being considered active ingredients. Their purification is difficult due to their chemical structural similarity and instability to light. In the present study, a coordination complex high-speed
Chiral total syntheses of all six insecticidal natural pyrethrins (three pyrethrin-I and three pyrethrin-II compounds) contained in the chrysanthemum (pyrethrum) flower were performed. Three common alcohol components [(S)-cinerolone, (S)-jasmololone, (S)-pyrethrolone] were
Pyrethrins are effective food-grade bio-pesticides obtained from the flowers of Chrysanthemum cinerariaefolium and this crop cannot be cultivated widely in India due to its specific agro-climatic requirement. Hence pyrethrins are mostly imported from Kenya. Therefore, the present study aims to