http://dzumenvis.nic.in/Physiology/pdf/Bioactive%20polyacetylenes%20in%20food%20plants.pdf

Bioactive polyacetylenes in food plants of the Apiaceae family: Occurrence, bioactivity and analysis

Biosynthesis and Function of Polyacetylenes and Allied Natural Products

https://digitalcommons.unl.edu/cgi/viewcontent.cgi?article=1377&context=usdaarsfacpub

Inoculation of coffee plants with the fungal entomopathogen Beauveria bassiana (Ascomycota: Hypocreales).

This paper presents an approach to simultaneously analyze polyacetylenes, carotenoids, and polysaccharides in carrot (Daucus carota L.) roots by means of Raman spectroscopy. The components were measured in situ in the plant tissue without any preliminary sample preparation. The analysis is based on the intensive and characteristic key bands observed in the Raman spectrum of carrot root. The molecular structures of the main carrot polyacetylenes, falcarinol and falcarindiol, are similar, but their Raman spectra exhibit specific differences demonstrated by the shift of their −C⋮C− mode from 2258 to 2252 cm-1, respectively. Carotenoids can be identified by −CC− stretching vibrations (about 1520 and 1155 cm-1) of the conjugated system of their polyene chain, whereas the characteristic Raman band at 478 cm-1 indicates the skeletal vibration mode of starch molecule. The other polysaccharide, pectin, can be identified by the characteristic band at 854 cm-1, which is due to the −C−O−C− skeletal mode of α-anomer c...

/pdf/in-situ-simultaneous-analysis-of-polyacetylenes-carotenoids-1w5ccwwf97.pdf

In situ simultaneous analysis of polyacetylenes, carotenoids and polysaccharides in carrot roots.

Propenylbenzenes, coumarins, and a polyacetylene, identified in the surface wax of carrot leaves, stimulate oviposition in the carrot fly. These compounds are known to be powerful inhibitors of the growth of bacteria, fungi, plants, and nonadapted herbivores. Their co-occurence appears to be unique to the Umbelliferae, the host plant family of the carrot fly. An artificial mixture of these compounds proved to be synergistic and as stimulatory as the crude carrot leaf extract.

Defense chemicals in leaf surface wax synergistically stimulate oviposition by a phytophagous insect

A compound isolated from root tissue extracts of Daucus carota L. showed antifungal activity towards Mycocentrospora acerina and Cladosporium cladosporioides . It was identified with the aid of u.v. and infrared spectroscopy, nuclear magnetic resonance and mass spectrometry as cis -heptadeca-1,9-diene-4,6-diyne-3,8-diol with the trivial name of falcarindiol. A concentration gradient in carrot roots varying from 93 μg/g fresh wt in periderm and pericyclic parenchyma to 2 μg/g in xylem parenchyma was demostrated. The ED 50 for inhibition of germination of chlamydospores of M. acerina was 31·8 μg/ml. The role of this compound in disease resistance is discussed.

Cis-heptadeca-1,9-diene-4,6-diyne-3,8-diol, an antifungal polyacetylene from carrot root tissue

On potato tuber surfaces at 12° and 20 °C indirect germination of sporangia of Phytophthora infestans was stimulated to levels above those in distilled water. Following indirect sporangial germination, zoospores accumulated preferentially on the lenticels. As the tuber developed and lenticels became more resistant, the number of zoospores accumulating and the proportion subsequently germinating decreased. Differences in the proportion of zoospores germinating on different cultivars were related to cultivar resistance at 20 °C but not at 12 °C. Accumulation of zoospores involved a response to a diffusible stimulus produced by the lenticels.

Behaviour of Phytophthora infestans (Mont.) de Bary on potato tubers in relation to lenticel resistance

In a range of Coffea genotypes, resistance at the SH1 and SH2 loci was associated with accumulation of antifungal substances in leaf diffusates in response to incompatible races of Hemileia vastatrix. Spore germination and germ-tube extension were suppressed. However, with compatible combinations of host and pathogen, the diffusates did not suppress germination and stimulated germ-tube extension. Inoculation of leaves with an incompatible race of the fungus decreased the subsequent proportion of each leaf infected by a compatible one.

B.G. Lewis

Papers

Cis-heptadeca-1,9-diene-4,6-diyne-3,8-diol, an antifungal polyacetylene from carrot root tissue

Behaviour of Phytophthora infestans (Mont.) de Bary on potato tubers in relation to lenticel resistance

Relationship between a phytoalexin-like response in coffee leaves (Coffea arabica L.) and compatibility with Hemileia vastatrix Berk. & Br