Volatile Chemical Compounds in Dry-Cured Hamsb

ABSTRACT Several species of entomopathogenic nematodes have different host-seeking methods, and could be considered as "ambusher" or "cruiser". These differences may depend on how the nematodes detect the volatile signals used as cues for foraging. This study aimed to evaluate the locomotor response of Heterorhabditis amazonensis RSC5 to the compounds from root exudates of different plants, as well as to stimulants produced by the presence of insects or to the feeding activity of insects on plants. Arenas with agar-water substrates, containing root exudates from corn, bean, soybean, cucumber, garlic and tomato seedlings, were assembled to determine the substrates possibly preferred by H. amazonensis.Arenas with sand were also constructed to include, besides the seedling root exudates, treatments containing Spodoptera frugiperda, garlic seedlings and S. frugiperda feeding on garlic seedlings. The H. amazonensis species was attracted to the volatile chemicals emitted by all the root exudates tested, especially the exudate from garlic seedlings. However, it showed the greatest attraction to the combination of garlic seedlings and S. frugiperda, indicating that the search of H. amazonensis for its host is enhanced by the association between the insect and the volatile chemical compounds produced by plants, when attacked by insects.

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Antifungal efficacy of Moringa oleifera leaf and seed extracts against Botrytis cinerea causing gray mold disease of tomato (Solanum lycopersicum L.)

Brazilian Journal of Biology ◽

10.1590/1519-6984.233173 ◽

2020 ◽

Author(s):

T. Ahmadu ◽

K. Ahmad ◽

S. I. Ismail ◽

O. Rashed ◽

N. Asib ◽

...

Keyword(s):

Electron Microscopy ◽

Mass Spectrometry ◽

Growth Inhibition ◽

Botrytis Cinerea ◽

Mycelial Growth ◽

Leaf Extract ◽

Moringa Oleifera ◽

Chemical Compounds ◽

Volatile Chemical Compounds ◽

Chemical Fungicides

Abstract Drawbacks associated with the use of chemical fungicides to control plant pathogenic fungi such as Botrytis cinerea stimulate the need for alternatives. Therefore, the present study was carried out to determine the antifungal potentials of Moringa oleifera extracts against B. cinerea. Phytochemical analysis using qualitative chemical tests revealed the presence of huge amount of crucial phytochemicals compounds like phenolic compounds, alkaloids and saponins in the M. oleifera leaf extract. Antifungal bioassay of the crude extracts indicated better mycelial growth inhibition by methanol leaf extract (99%). The minimum inhibitory concentration (MIC) was 5 mg/ml with 100% spore germination inhibition and minimum fungicidal concentration (MFC) was 10 mg/ml with 98.10% mycelial growth inhibition using broth micro dilution and poisoned food techniques. Gas chromatography–mass spectrometry (GC-MS) analysis led to the identification of 67 volatile chemical compounds in the leaf extract with 6-decenoic acid (Z)- (19.87%) was the predominant compound. Further chemical elucidation of the crude extracts performed by liquid chromatography with tandem mass spectrometry (LC-MS/MS) showed the presence of non-volatile chemical compounds, mostly flavones, flavonoids and phenolic acids (i.e. quercetin and kaempferol). Scanning electron microscopy and transmission electron microscopy analysis showed positive effect of M. oleifera leaf extract on the treated conidia and mycelium of B. cinerea. Findings revealed that irreversible surface and ultra-structural changes with severe detrimental effects on conidia and mycelium morphology compared to control treatment. Overall findings suggested that M. oleifera leaf extract is a promising candidate for biological control of fungal pathogens, thus limiting overdependence on chemical fungicides.

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Major Volatile Chemical Compounds of Agarwood Oils from Malaysia Based on Z-Score Technique

Chemistry of Natural Compounds ◽

10.1007/s10600-015-1409-2 ◽

2015 ◽

Vol 51 (4) ◽

pp. 776-779 ◽

Cited By ~ 1

Author(s):

Nurlaila Ismail ◽

Nor Azah Mohd Ali ◽

Mailina Jamil ◽

Mohd Hezri Fazalul Rahiman ◽

Mohd Nasir Taib ◽

...

Keyword(s):

Chemical Compounds ◽

Z Score ◽

Volatile Chemical Compounds

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Cytochemical analysis of mast cell granules after poly-dl-lysine action

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s042482010008225x ◽

1978 ◽

Vol 36 (2) ◽

pp. 278-279

Author(s):

R. Courtoy ◽

L.J. Simar ◽

J. Christophe

Keyword(s):

Mast Cell ◽

Mast Cells ◽

Chemical Compounds ◽

Cellular Membrane ◽

Thin Sections ◽

Organic Bases ◽

Ferric Thiocyanate ◽

Cytochemical Analysis ◽

Mast Cell Granule ◽

Amine Liberation

Several chemical compounds induce amine liberation from mast cells but do not necessarily provoque the granule expulsion. For example, poly-dl-lysine induces modifications of the cellular membrane permeability which promotes ion exchange at the level of mast cell granules. Few of them are expulsed but the majority remains in the cytoplasm and appears less dense to the electrons. A cytochemical analysis has been performed to determine the composition of these granules after the polylysine action.We have previously reported that it was possible to demonstrate polyanions on epon thin sections using a cetylpyridinium ferric thiocyanate method. Organic bases are selectively stained with cobalt thiocyanate and the sulfhydryle groups are characterized with a silver methenamine reaction. These techniques permit to reveal the mast cell granule constituents, i.e. heparin, biogenic amines and basic proteins.

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Growth of near noble metal Pd and Pt thin film silicides morphology and structure

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100112464 ◽

1984 ◽

Vol 42 ◽

pp. 498-499

Author(s):

E. I. Alessandrini ◽

M. O. Aboelfotoh

Keyword(s):

Noble Metals ◽

Annealing Temperature ◽

Chemical Compounds ◽

Barrier Properties ◽

Solid State Reactions ◽

Transmission Electron ◽

Stable Chemical ◽

Metal Thickness ◽

Amorphous Si ◽

Si Films

Considerable interest has been generated in solid state reactions between thin films of near noble metals and silicon. These metals deposited on Si form numerous stable chemical compounds at low temperatures and have found applications as Schottky barrier contacts to silicon in VLSI devices. Since the very first phase that nucleates in contact with Si determines the barrier properties, the purpose of our study was to investigate the silicide formation of the near noble metals, Pd and Pt, at very thin thickness of the metal films on amorphous silicon.Films of Pd and Pt in the thickness range of 0.5nm to 20nm were made by room temperature evaporation on 40nm thick amorphous Si films, which were first deposited on 30nm thick amorphous Si3N4 membranes in a window configuration. The deposition rate was 0.1 to 0.5nm/sec and the pressure during deposition was 3 x 10 -7 Torr. The samples were annealed at temperatures in the range from 200° to 650°C in a furnace with helium purified by hot (950°C) Ti particles. Transmission electron microscopy and diffraction techniques were used to evaluate changes in structure and morphology of the phases formed as a function of metal thickness and annealing temperature.

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