Occurrence of pyridines and other bases in orange oil

Geranium (Pelargonium sp.) Essential Oil from Reunion. Minor Compounds: Acids, Phenols, Pyridines

“…Besides the usual alkanoic acids (C 1 to C 10 ), they reported the presence of some monoterpenic (neric, geranic, citronellic) and aromatic (benzoic, salicyclic and phenylacetic) acids. In addition to the acids, some pyridines have been identified in natural products (7)(8)(9)(10)(11)(12)(13). Our previous works on geranium oil (14,15) led us to undertake a further study on the minor compounds (acids, phenols and pyridines) of a geranium Bourbon oil.…”

The kinetic analysis of the N -methylation of 4-phenylpyridine by nicotinamide N -methyltransferase: Evidence for a novel mechanism of substrate inhibition

“…4-Phenylpyridine (4-PP) is of interest because its N-methylated derivative is MPP+. 4-PP is an exogenously-derived compound found in, amongst others, oranges (Thomas and Bassols, 1992) and mint (Snyder and D'Amato, 1985). 4-PP N-methylation by NNMT provides a direct metabolic pathway for the endogenous production of MPP+ ( Fig.…”

High‐impact odorants in essential oils

“…The high price or scarcity of the natural oil is often the driver behind this work, but it can also simply be the search for new aroma compounds that impart the recognizable character of the natural oil. This applies equally in both fl avour and fragrance research and over time has led to the discovery of some important materials used in the fl avour and fragrance industry, such as the thio-esters in galbanum, [1] oxane from passion fruit, [2] grapefruit thiol [3] and 3-hexylpyridine from orange, [4] and continues to date with the discovery of Yuzuol [(6Z,8E)-undeca-6,8,10-trien-4-ol] [5] and (Z)-4-hepten-2-yl salicylate ( Figure 1). [6,7] The principal analytical technique used in the determination of odorants in essential oils is gas chromatography-olfactometry (GC-O), which is as old as the science of gas chromatography (GC) itself, since early experiments in GC involved smelling the effl uent from the column to detect the analytes.…”

“…[23,11] Other sulphur compounds occurring in foods have been reviewed by Boelens. [24] In addition to the extremely powerful 2-sec-butyl-3-methoxy pyrazine, other nitrogenous compounds, notably pyrazines and pyridines, also have low threshold values and have been identifi ed as trace components in a range of essential oils, including orange, [4] black pepper, [25] vetiver [26] and ambrette seed, [27] where they contribute subtly but importantly to the odour of the natural oil.…”