M. B. Terenina

Antioxidant properties of essential oils

By the method of capillary gas-liquid chromatography, we studied the antioxidant properties and stability during the storage of hexane solutions of 14 individual essential oils from black and white pepper (Piper nigrum L.), cardamom (Elettaria cardamomum L.), nutmeg (Myristica fragrans Houtt.), mace (Myristica fragrans Houtt), juniper berry (Juniperus communis L.), fennel seed (Foeniculum vulgare Mill., var. dulce Thelling), caraway (Carvum carvi L.), dry cinnamon leaves (Cinnamomum zeylanicum Bl.), marjoram (Origanum majorana L.), laurel (Laurus nobilis L.), ginger (Zingiber officinale L.), garlic (Allium sativum L.), and clove bud (Caryophyllus aromaticus L.). We assessed the antioxidant properties by the oxidation of aliphatic aldehyde (trans-2-hexenal) into the corresponding carbonic acid. We established that essential oils of garlic, clove bud, ginger and leaves of cinnamon have the maximal efficiency of inhibiting hexenal oxidation (80!–93%), while black pepper oil has the minimal (49%). Antioxidant properties of essential oils with a high content of substituted phenols depended poorly on their concentrations in model systems. We studied the changes in the composition of essential oils during the storage of their hexane solutions for 40 days in light and compared it with the stability of essential oils stored for a year in darkness.

The composition of volatile components of cepe (Boletus edulis) and oyster mushrooms (Pleurotus ostreatus)

The composition of aroma compounds in cooked and canned cepe (Boletus edulis) and in cooked oyster mushrooms (Pleurotus ostreatus) is studied using capillary gas chromatography and chromatographymass spectrometry. It is found that unsaturated alcohols and ketones containing eight atoms of carbon determine the aroma of raw mushrooms and take part in the formation of the aroma of cooked mushrooms as well. The content of these compounds was the highest in canned cepes. In oyster mushrooms, the concentration of these alcohols and ketones was lower in comparison with cepes. The content of aliphatic and aromatic aldehydes was much higher in oyster mushrooms. Volatile aliphatic and heterocyclic Maillard reaction products and isomeric octenols and octenones formed the aroma of cooked and canned mushrooms.

Formation of flavor of dry champignons (Agaricus bisporus L.)

The composition of aroma compounds of dry champignons (Agaricus bisporus L.) were identified using capillary gas chromatography and chromatography-mass spectrometry. In total, 56 compounds were identified. It was found that the flavor of dry mushrooms was formed by the volatile compounds produced as a result of enzymatic and oxidative conversion of unsaturated fatty acids as well as in the Maillard reaction. Unsaturated alcohols and ketones containing eight carbon atoms determined the mushroom note of the product. The specific aroma of dry mushrooms was determined by a complex composition of substituted sul- fur-, oxygen-, and nitrogen-containing heterocyclic compounds as well as by aliphatic carbonyl compounds and methional. It was found that the concentrations of volatile carbonylic and heterocyclic compounds increased after the addition of a mixture of amino acids to mushrooms before drying. As a result, the intensity of the aroma of dry mushrooms increased.

GC evaluation of flavour compound sorption from water solutions by corn starch cryotextures obtained by freezing

Sorption of essential oil aroma components, n-alcohols and linalool by starch corn cryotexture was studied. Results show that terpene hydrocarbons of Rosmarinus officinalis L. essential oil are sorbed quantitatively from 0.05% water solution by cryotexture due to hydrophobic interactions with starch polysaccharides. Aroma compounds with oxygen atoms within the molecule are sorbed two times less. A templating effect with glucose, sucrose, maltose and some essential oil components was observed. Sorption of n-alcohols C4, C6, C8, linalool and their mixture with alkyl acetates in concentration 0.5-15 mmol/l was carried out. Individual octanol is sorbed by cryotexture on 88%, hexanol on 20%, linalool on 25%. Butanol is not sorbed at the chosen concentration. Synergism in sorption of hexanol from mixture with octanol and alkyl acetates was observed, while a suppression effect of octanol sorption was found for the same mixture.

Oregano essential oil as an inhibitor of higher fatty acid oxidation

Inhibition of the oxidation of fatty acids methyl esters by oregano essential oil was studied using capillary gas chromatography. A mixture of fatty acids which contained saturated, mono-, di-, and polyunsaturated acids with 16–24 carbon atoms was extracted from mice brain. Changes in the composition of esters in hexane solutions both in the presence of oregano essential oil and without it were examined during their autooxidation in light for 1 year. It was found that the oxidation rate of unsaturated fatty acids increases with increasing degree of their unsaturation. Oregano essential oil inhibited the oxidation process. Antioxidant activity of the oil increased with increase of its concentration. It was shown that carvacrol and thymol are the main antioxidant components of oregano oil.

Formation of Supramolecular Structures of Aroma Compounds with Polysaccharides of Corn Starch Cryotextures

The binding absorption of individual alcohols, ketones, alkyl acetates and their mixtures - used as aroma compounds - from aqueous solutions by corn starch cryotextures was studied by capillary gas chromatography at different starting concentrations of the odourants (1-25 mmol/L). The amount of compound sorbed by the cryotextures increases with concentration of this compound in the initial sol and increasing length of the alkyl chain in the corresponding compound. Linear equations describing the concentration dependence were proposed. The presence of octanol in the mixture increases the binding of hexanol as compared to hexanol alone. The methods of scanning electron microscopy (SEM), X-ray photoelectron spectroscopy, differential scanning microcalorimetry (DSC) and scanning tunneling microscopy (STM) were used for estimation of the microstructure of sols, and cryotextures, and for the determination of supramolecular complex formation in the systems odourant/cryotexture and odourant/ sol. It was shown that waxy corn cryotextures do not form supramolecular complexes with aroma compounds.

[Autooxidation of a mixture of lemon essential oils, methyl linolenoate, and methyl oleinate].

Stability of components of a mixture of methyl linolenoate and methyl oleinate with two lemon (Citrus limon L.) essential oils in hexane during their autooxidation in light was studied by gas chromatography. The essential oils differed by their quantitative ratio of components: the single-fold (1x) oil contained approximately 90% monoterpene hydrocarbons and 1.47% citral, whereas the proportions of hydrocarbons and citral in the tenfold (10x) oil were approximately 60 and 18.32%, respectively. The concentration and composition of essential oils influence the rates of fatty-acid oxidation and fatty-acid peroxide cleavage. The 1x lemon oil inhibited the oxidation of methyl linolenoate and methyl oleinate, whereas the 10x oil accelerated these processes. The distinctions in the resistance of the major components of lemon essential oil to oxidation, which are determined by their composition and antioxidant properties of unsaturated fatty acids, were revealed.

The composition of volatile components of dry cepe and oyster mushroom

The composition of aroma compounds in dry cepe mushroom (Boletis edulis Fr.) and oyster mushroom (Pleurotus ostreatus Fr.) was studied using capillary gas chromatography and chromatography—mass spectrometry. In dry cepe, 53 volatile compounds were identified, and in dry oyster mushroom 41 compounds were identified. Volatile organic substances with various functional groups formed the flavor of dry mushrooms. Unsaturated alcohols and ketones with eight carbon atoms were responsible for the mushroom notes of products. Their content in dry cepe was much higher than in dry oyster mushroom. The specific aroma of dry cepe was formed by the complex mixture of methional, substituted furans, pyrazines, and pyrroles. The content of these compounds was higher in dry cepe than in dry oyster mushroom. The content of aromatic and aliphatic aldehydes with six, nine, and ten carbon atoms was higher in dry oyster mushroom. The differences in the qualitative and quantitative composition of volatile compounds are responsible for more intensive and pleasant aroma of dry cepe in comparison to that of dry oyster mushroom.

Inhibition of mouse aging by using an essential oil composition

167 Due to increasing life expectancy, the proportion of older people in the population increases, and the social importance of cognitive abilities is growing steadily. It is well known that, with age, the vast major ity of older people develop persistent pronounced cog nitive deficits that leads to disability and household independence and is defined as mild cognitive impair ment (MCI) [1]. This syndrome is a transitive condi tion between the physiological decline in cognitive function due to aging and the initial (preclinical) stage of Alzheimer’s disease (AD). The syndrome is charac terized by a borderline disorder of cognitive functions, including memory. In general, the MCI syndrome is extremely widespread. Since AD can be diagnosed in 40% of patients within three years after the diagnosis of MCI, an early diagnosis of the MCI syndrome and the prescription of appropriate drugs can delay the onset of dementia or even promote regression of cog nitive impairment characteristic of the early stages of AD [2].

[Sorption of components from a mixture of odorants by polysaccharides of starch, chitosan, and carrageenan].

Sorption of components from a mixture of odorants in aqueous suspensions of native cornstarch, chitosan, and carrageenan was studied by the method of capillary gas-liquid chromatography. Binding was primarily effected via hydrophobic cooperative interactions. The amount of sorbed odorants depended linearly on their initial concentration in the suspension. The differences in sorption characteristics of starch and chitosan were related to the presence of amino groups in the latter polysaccharide, which contributed to an increased binding of aldehydes via polar interactions. Sorption of odorants by the sulfated polysaccharide carrageenan largely depended on the structure of odorants and properties of their functional groups. Carrageenan was potent in binding aldehydes, ketones, and esters. Alcohols were less strongly bound to this polysaccharide. Sorption of lactones and guaiacol by carrageenan was the least significant.