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1.
Phytother Res ; 33(10): 2749-2764, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31328343

RESUMO

Guava (Psidium guajava) is a widely consumed fruit and has been commercialized in markets. The seeds are by-products of the processing procedures performed by the commercial guava juice industry. They are considered a nutritional resource that has been poorly utilized as they contain essential fatty acids such as linoleic acid (LA) and phenolics in abundance. In the study, guava seed oil (GSO) was used, which was obtained by hexane extraction of guava seeds to determine composition and test toxicity, cell migration, cancer cell viability, and plasmodium growth. GSO was found to be relatively nontoxic to normal hepatocytes and peripheral blood mononuclear cells, with mice for 14 days showing median lethal dose (LD50 ) > 10 mg/kg and rats for up to 90 days. Surprisingly, the oil inhibited the proliferation of the human erythroleukemic cells in a dose-dependent manner with the half maximal inhibitory concentration values of 155 and 137 µg/ml at 24 and 48 hr, respectively. Importantly, GSO at 500 µg/ml was found to increase the degree of migration of keratinocytes (HaCaT). These observations suggest that edible P. guajava seed oil, which is abundant with linoleic acid and antioxidants, can promote skin wound healing and inhibit the proliferation of leukemic cells.


Assuntos
Ácido Linoleico/análise , Óleos Vegetais/farmacologia , Psidium , Animais , Antioxidantes/farmacologia , Células Hep G2 , Humanos , Masculino , Camundongos , Óleos Vegetais/toxicidade , Psidium/química , Ratos , Ratos Wistar , Sementes/química
2.
J Food Sci ; 84(8): 2121-2127, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31269247

RESUMO

The effects of thermal oxidation at 65 °C for 24 days on oxidation indices, fatty acid positional distribution, thermal properties, vitamin E composition and sterol composition of kenaf seed oil are investigated. The results showed that total oxidation value (TOTOX) of the oil increased from initial 8.83 to 130.74 at the end of 24 days storage. Linoleic acid at sn-1, 3 positon of kenaf seed oil was less stable than the one at sn-2 positon. Oxidative degradation changed the melting profile of kenaf seed oil, the value of endothermic enthalpy reduced from 58.17 to 20.25 J/g after 24 days of storage. Moreover, the content of vitamin E and total sterol decreased by 84.26% and 38.47%, respectively. Tocotrienols were more stable than tocopherols during the accelerated storage. Correlation analysis indicated vitamin E content was significantly related to p-anisidine value, while sterol content was significantly related to peroxide value. PRACTICAL APPLICATION: Kenaf seed oil is rich in polyunsaturated fatty acids and bioactive compounds. Heating process and long-term storage cause oil oxidation and bioactive compounds degradation. The oxidation process of kenaf seed oil is simulated with accelerated storage. The study evaluates fatty acid composition and distribution, vitamin E and sterol content, melting thermal characteristics of kenaf seed oil at different oxidation levels. The research shows the stability of fatty acid is related with its type and position in backbone of triacylglycerol molecule. There are good correlation among oxidation level, vitamin E and sterol content, and melting enthalpy value of kenaf seed oil.


Assuntos
Ácidos Graxos/química , Hibiscus/química , Óleos Vegetais/química , Armazenamento de Alimentos , Temperatura Alta , Ácido Linoleico/análise , Oxirredução , Sementes/química , Tocoferóis/análise , Tocotrienóis/análise , Triglicerídeos/análise , Vitamina E/análise
3.
J Oleo Sci ; 68(7): 649-658, 2019 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-31178460

RESUMO

Camellia oleifera, C. japonica and C. sinensis are three representative crops of the genus Camellia. In this work, we systematically investigated the lipid characteristics of these seed oils collected from different regions. The results indicated significant differences in acid value (AV), peroxide value (PV), iodine value (IV), saponification value (SV) and relative density of the above-mentioned camellia seed oils (p < 0.05). The C. japonica seed oils showed the highest AV (1.7 mg/g), and the C. sinensis seed oils showed the highest PV (17.4 meq/kg). The C. japonica seed oils showed the lowest IV (79.9 g/100 g), SV (192.7 mg/g) and refractive index (1.4633) of all the oils, while the C. sinensis seed oils showed the lowest relative density (0.911 g/cm3). The major fatty acids in the camellia seed oils were palmitic acid (16:0), oleic acid (18:1) and linoleic acid (18:2); the oleic acid in C. oleifera and C. japonica seed oils accounted for more than 80% of the total fatty acids. The oleic acid levels in the C. oleifera and C. japonica oils were higher than those in the C. sinensis seed oils, while the linoleic acid levels in the former were lower than those in the latter one. Differences also exist in the triacylglycerol (TAG) composition, although the most abundant TAG molecular species in the camellia seed oils was trioleoylglycerol (OOO). Seven sterol species, squalene and α-tocopherol were detected in the camellia seed oils, however, the contents of tocopherol and unsaponifiable molecules in the C. oleifera and C. japonica seed oils were significantly lower than those in the C. sinensis seed oil. These results demonstrated that the varieties of Camellia affected the seed oil lipid characteristics.


Assuntos
Camellia/química , Ácido Linoleico/análise , Ácido Oleico/análise , Ácido Palmítico/análise , Óleos Vegetais/química , Sementes/química , Camellia/classificação , Fenômenos Químicos , Ácido Linoleico/isolamento & purificação , Ácido Oleico/isolamento & purificação , Ácido Palmítico/isolamento & purificação , Fitosteróis/análise , Fitosteróis/isolamento & purificação , Esqualeno/análise , Esqualeno/isolamento & purificação , Triglicerídeos/análise , Triglicerídeos/isolamento & purificação , Trioleína/análise , Trioleína/isolamento & purificação , alfa-Tocoferol/análise , alfa-Tocoferol/isolamento & purificação
4.
J Food Sci ; 84(7): 1937-1942, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31206672

RESUMO

Pistachio is an economically important nut crop in California. Since temperature variations among geographical locations can influence biochemical processes during fruit development, it is of great relevance to understand the impact of growing area over the components that define the nutritional and sensory characteristics of pistachio nuts. Changes in moisture, fat content, fatty acid composition and volatile terpenes were studied during kernel development for "Kerman" and "Golden Hills" varieties in two different California Central Valley microclimates, Lost Hills and Parlier. Moisture content decreased from July to September for both cultivars at both locations. Kerman had a higher moisture content at both locations compared with Golden Hills. Harvest time affected fat content only for Kerman, where the values increased drastically from 21-July to 4-Aug, then remained constant. Golden Hills' fat content remained constant during the period of the study. The main fatty acid in pistachio oil is oleic acid (46% to 59%), followed by linoleic acid (26% to 36%) and palmitic acid (11% to 16%). C16:0, C16:1, C18:2, and C18:3 decreased with harvest time, while C18:1 increased. α-Pinene was the most concentrated volatile among the cultivars and locations. It decreased with harvest time for both cultivars at both locations, ranging from 105 to 2464 mg/kg. At harvest, Golden Hills and Kerman at Parlier both had higher concentrations of α-pinene than the two cultivars at Lost Hills. Our results demonstrate that microclimate affects biosynthesis of fatty acids and terpenes in pistachio kernels, the main compounds responsible for pistachio nutritional and sensory characteristics.


Assuntos
Ácidos Graxos/química , Pistacia/química , Extratos Vegetais/química , Terpenos/química , California , Ácido Linoleico/análise , Microclima , Ácido Oleico/análise , Sementes/química
5.
Phytochemistry ; 160: 40-47, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30690343

RESUMO

The genus Pistacia (Anacardiaceae family) is represented by several species, of which only P. vera L. produces edible seeds (pistachio). Despite the different flavor and taste, a correct identification of pistachio varieties based on the sole phenotypic character is sometimes hard to achieve. Here we used a combination of chemical partitioning and molecular fingerprinting for the unequivocal identification of commercial pistachio seed varieties (Bronte, Kern, Kerman, Larnaka, Mateur and Mawardi) of different geographical origin. The total phenolic content was higher in the variety Bronte followed by Larnaka and Mawardi cultivars. The total anthocyanin content was higher in Bronte and Larnaka varieties, whereas the total proanthocyanidin content was higher in Bronte, followed by Mawardi and Larnaka varieties. HPLC-DAD-ESI-MS/MS analyses revealed significant (P < 0.05) higher amounts of cyanidin-3-glucoside, idein, eryodictol-7-galactoside, quercetin-3-glucoside, luteolin-glucoside and marein in the variety Bronte, whereas higher amounts of peonidin-3-glucoside, okanin 4'-galactoside, hyperoside and quercetin-4'-glucoside were found in the variety Larnaka. The highest content of catechin was found in the Mawardi variety. A significantly (P < 0.05) higher total amount of fatty acids was found in the varieties Mateur, Kern and Bronte, followed by the varieties Larnaka and Mawardi, whereas the variety Kerman showed the lowest total fatty acid content. GC-FID and GC-MS analyses revealed the presence of several polyunsaturated fatty acids. Kern and Mateur varieties showed a significantly (P < 0.05) higher amount of linoleic acid, whereas the variety Bronte showed the highest amount of oleic acid. Molecular fingerprinting was achieved by ITS DNA PCR-RFLP analysis. Three different restriction enzymes (RsaI, TaqαI and PstI) were used to selectively cleave the resulting amplicons. A TaqαI site could be selectively found in the varieties Kerman, Larnaka and Mateur, whereas the digestion of the PCR products by RsaI gave specific patters exclusively on Bronte and Mawardi. Digestion by PstI gave specific patters exclusively on the Kern variety. The results showed that the Mediterranean varieties (Mateur, Bronte and Larnaka) show similar chemical patterns and (particularly for Mateur and Larnaka) a close phylogenetic relationship, allowing a chemical and molecular partitioning with respect to the other varieties.


Assuntos
Impressões Digitais de DNA , Geografia , Pistacia/química , Pistacia/classificação , Antocianinas/análise , Ácido Linoleico/análise , Ácido Oleico/análise , Filogenia , Sementes/química
6.
Food Chem ; 279: 216-222, 2019 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-30611483

RESUMO

The effects of amphiphilic compounds on the dielectric constant of bulk oils were determined and the utility of the dielectric constant as a reliable parameter for predicting the oxidative stability of edible oils was evaluated. As the content of monoacylglycerols (MAGs), lecithin, and moisture increased, the dielectric constant of modified corn oil increased at different rates, whereas the addition of free fatty acids, including oleic and linoleic acid, decreased the dielectric constant of modified corn oil. Unoxidized fresh bulk oils showed a wide range of dielectric constants, from 8 for canola oils to 33 for flaxseed oils. The dielectric constant showed a strong correlation with the percentage of unsaturated fatty acids in the bulk oils. Oils with low oxidative stability had a high dielectric constant. Overall, the dielectric constant of bulk oils is strongly correlated with the content of amphiphilic compounds, moisture content, and degree of unsaturation of fatty acids.


Assuntos
Ácidos Graxos não Esterificados/análise , Óleos Vegetais/química , Antioxidantes/química , Óleo de Milho/química , Ácidos Graxos não Esterificados/química , Lecitinas/análise , Lecitinas/química , Ácido Linoleico/análise , Ácido Linoleico/química , Óleo de Semente do Linho/química , Monoglicerídeos/análise , Monoglicerídeos/química , Oxirredução
7.
J Sci Food Agric ; 99(7): 3635-3643, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30629293

RESUMO

BACKGROUND: The aim of the study was to evaluate the nutritional properties of milk and cheese obtained from Friesian cows fed with a diet supplemented with dried grape pomace, a by-product of the oenological industry, which is very rich in polyphenols. This approach is inspired by the increasing interest in foods containing functional ingredients that may have beneficial effects on human health. During the testing period, analyses of the chemical and nutritional properties of milk and dairy products derived from it were performed; particular attention was given to the effect of cheese ripening on the oxidative stability and fermentation process, evaluating respectively the presence of malondialdehyde and γ-aminobutyric acid. RESULTS: Dietary enrichment with grape pomace did not affect the milk composition but induced modifications in the fatty acid profiles in both milk and cheese with an increase in concentration of linoleic acid, trans-vaccenic acid, rumenic acid and total n-6 fatty acids. Moreover, after 30 days of cheese ripening, an increased oxidative stability and an increased concentration of γ-aminobutyric acid were found. CONCLUSIONS: Our results indicated a general improvement in nutritional parameters of milk and related cheese obtained from Friesian cows that received the feeding enrichment with dried grape pomace. Further analysis should be performed to improve knowledge of the chemical and microbiological mechanisms at the source of these findings. © 2019 Society of Chemical Industry.


Assuntos
Ração Animal/análise , Bovinos/metabolismo , Queijo/análise , Leite/química , Vitis/metabolismo , Resíduos/análise , Animais , Suplementos Nutricionais/análise , Feminino , Fermentação , Ácido Linoleico/análise , Ácido Linoleico/metabolismo , Leite/metabolismo , Valor Nutritivo , Oxirredução , Polifenóis/análise , Polifenóis/metabolismo , Vitis/química
8.
Food Res Int ; 115: 209-218, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-30599933

RESUMO

Lactococcus lactis subsp. lactis 68, Streptococcus thermophilus 93 and Lactobacillus rhamnosus BT68, previously isolated from Traditional Mountain (TM) cheese, were tested for the production of four experimental mountain cheeses, with the aim to assess their effectiveness in leading the TM-cheese-making process. Lactococcus lactis subsp. lactis 68 and Streptococcus thermophilus 93 were used as starter cultures, whereas Lactobacillus rhamnosus BT68 was used as non-starter culture. Three control (CTRL) cheeses were manufactured without adding any starter, according to the traditional cheese-making process; nine, cheeses were produced inoculating the vat milk with the starters (ST), starter and low concentration of non-starter culture (STLC), starter and high concentration of non-starter culture (STHC). Samples of vat milk, cheese after 24 h and 7 months ripening were processed for microbiological counts. Mesophilic cocci were dominant in all 24 h-cheese samples, while a dominance of both cocci and lactobacilli was observed after 7 months ripening. The total genomic DNA was extracted, and a fragment of V1-V3 region was amplified and pyrosequenced. Lactococci and streptococci were the most abundant species, and Lc. lactis ssp. lactis 68 affected the proliferation of milk-resident Lc. lactis ssp. cremoris, during the early fermentation. Lb. rhamnosus BT68 showed to be responsible in reducing the abundance of other Lactobacillus species. Moreover, it likely competed against Sc. thermophilus 93 for the same energetic sources, when added in concentration higher than 5 × 103 CFU/mL milk. The sensorial and fatty acid (FA) composition analysis were performed on cheese samples at the end of ripening, demonstrating that the inoculated cheeses had better sensorial characteristics (aspect, smell, taste, texture) than CTRL cheeses, and that Lb. rhamnosus BT68 at high concentration is related to the increase of short chain fatty acids and conjugated linoleic acid in cheese after 7 months ripening.


Assuntos
Queijo/microbiologia , Lactobacillales/isolamento & purificação , Lactobacillales/metabolismo , Animais , Biodiversidade , Evolução Biológica , Contagem de Colônia Microbiana , Cultura , DNA Bacteriano/isolamento & purificação , Ácidos Graxos/análise , Fermentação , Microbiologia de Alimentos , Lactobacillales/genética , Lactobacillus rhamnosus/metabolismo , Lactococcus lactis/metabolismo , Ácido Linoleico/análise , Leite/microbiologia , Streptococcus thermophilus/metabolismo , Paladar
9.
Meat Sci ; 149: 141-148, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30528718

RESUMO

Bologna-type sausages were made with 25, 50, 75 and 100% replacement of pork back fat by oleogel made with pork skin, water, and high oleic sunflower oil (HOSO) (1.5, 1.5: 1). The technological, nutritional, oxidative, and sensory properties were evaluated. Emulsion stability increased and cooking loss decreased with increasing the pork back fat replacement by oleogel. The reformulation increased the proportion of oleic acid within the lipid fraction by up to 20% and decreased the proportion of linoleic acid by up to 10%, with no changes in the oxidative stability. The acceptance and the sensory profile of the samples were not affected by the substitution of up to 50% of pork back fat by oleogel. Thus, the results showed that it is possible to produce Bologna-type sausages with reduced fat (~16% fat, ~29% reduction), cholesterol (40 mg, ~10% reduction), and energy value (~210 kcal/100 g, ~21% reduction) and with healthier lipid profile using oleogel from HOSO.


Assuntos
Produtos da Carne/análise , Ácido Oleico/análise , Adolescente , Adulto , Idoso , Animais , Comportamento do Consumidor , Culinária , Substitutos da Gordura/análise , Feminino , Humanos , Ácido Linoleico/análise , Masculino , Pessoa de Meia-Idade , Compostos Orgânicos , Óleo de Girassol , Suínos , Paladar
10.
Plant Physiol Biochem ; 135: 127-131, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30529978

RESUMO

The compositions of the seed oils obtained by hexane extraction of three members of the Ficus genus of the Moraceae plant family was determined, namely Ficus nota, Ficus septica, Ficus ulmifolia. Linolenic acid is the most prominent fatty acid in the seed oils followed by linoleic acid, with these two fatty acid comprising about 75% of the fatty acids in the oils. The high level of polyunsaturated fatty acids coincides with high levels of these acids predominating among the fatty acids observed in various plant parts of other Ficus species. Besides the fatty acids, a variety of phytochemicals also found in other plant parts of Ficus species were observed in the seed oils, including squalene, pentacyclic triterpenes such as α-amyrin, ß-amyrin and lupeol, as well as sterols such as cholesterol and γ-sitosterol, the former at unusually elevated levels. The levels of these phytochemicals vary from species to species and location of harvest, with F. ulmifolia showing by far the highest level of these materials and with α-amyrin, ß-amyrin and lupeol being the most common, their amounts exceeding those of fatty acids for samples from one specific location. Surprisingly, low levels of macrocyclic alkanes in the range of C24-C30 were identified.


Assuntos
Cicloparafinas/análise , Ácidos Graxos/análise , Ficus/metabolismo , Óleos Vegetais/química , Sementes/química , Triterpenos/análise , Ficus/química , Ácido Linoleico/análise , Ácido alfa-Linoleico/análise
11.
Food Chem ; 274: 808-815, 2019 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-30373014

RESUMO

Rambutan seed is usually discarded during fruit processing. However, the seed contains a considerable amount of crude fat. Hence, the objective of this study was to investigate the fat properties and antinutrient content of the seed during fermentation of rambutan fruit. Results showed that the crude fat content of the seed reduced by 22% while its free fatty acid content increased by 4.3 folds after 10 days of fermentation. Arachidic acid was selectively reduced and was replaced by linoleic acid from the seventh day of fermentation onwards. Only 14.5% of triacylglycerol remained in the seed fat at the end of fermentation. The complete melting temperature, crystallization onset temperature and solid fat index at 37 °C of the fermented seed fat were higher than that of non-fermented seed fat. The saponin and tannin contents of the seed were reduced by 67% and 47%, respectively, after fermentation.


Assuntos
Ácidos Graxos/análise , Manipulação de Alimentos/métodos , Sapindaceae/química , Sementes/química , Cristalização , Ácidos Eicosanoicos/análise , Ácidos Eicosanoicos/metabolismo , Ácidos Graxos/metabolismo , Ácidos Graxos não Esterificados/metabolismo , Fermentação , Frutas/química , Frutas/metabolismo , Ácido Linoleico/análise , Ácido Linoleico/metabolismo , Sapindaceae/metabolismo , Saponinas/análise , Sementes/metabolismo , Taninos/análise , Temperatura Ambiente , Triglicerídeos/análise , Triglicerídeos/metabolismo
12.
Br J Nutr ; 121(1): 65-73, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-30378505

RESUMO

This study quantified the fatty acid profile with emphasis on the stereo-specifically numbered (sn) 2 positional distribution in TAG and the composition of main phospholipids at different lactation stages. Colostrum milk (n 70), transitional milk (n 96) and mature milk (n 82) were obtained longitudinally from healthy lactating women in Shanghai. During lactation, total fatty acid content increased, with SFA dominating in fatty acid profile. A high ratio of n-6:n-3 PUFA was observed as 11:1 over lactation due to the abundance of linoleic acid in Chinese human milk. As the main SFA, palmitic acid showed absolute sn-2 selectivity, while oleic acid, linoleic acid and α-linolenic acid, the main unsaturated fatty acids, were primarily esterified at the sn-1 and sn-3 positions. Nervonic acid and C22 PUFA including DHA were more enriched in colostrum with an sn-2 positional preference. A total of three dominant phospholipids (phosphatidylethanolamine (PE), phosphatidylcholine (PC) and sphingomyelin (SM)) were analysed in the collected samples, and each showed a decline in amount over lactation. PC was the dominant compound followed by SM and PE. With prolonged breast-feeding time, percentage of PE in total phospholipids remained constant, but PC decreased, and SM increased. Results from this study indicated a lipid profile different from Western reports and may aid the development of future infant formula more suitable for Chinese babies.


Assuntos
Colostro/química , Ácidos Graxos/análise , Leite Humano/química , Fosfolipídeos/análise , Adulto , Grupo com Ancestrais do Continente Asiático , China , Ácidos Docosa-Hexaenoicos/análise , Ácidos Graxos Ômega-3/análise , Ácidos Graxos Ômega-6/análise , Feminino , Humanos , Lactação/fisiologia , Ácido Linoleico/análise , Ácido Oleico/análise , Ácido Palmítico/análise , Fatores de Tempo , Ácido alfa-Linoleico/análise
13.
J Dairy Sci ; 102(2): 1025-1032, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30580937

RESUMO

The aim of the present work was to explore the chemical-sensorial characteristics and aromatic profile of caciotta cheese obtained from Friesian cows fed a diet enriched with grape pomace obtained from red grape (Vitis vinifera L.). Dietary enrichment with grape pomace influenced the production of caciotta cheeses in interesting ways from a compositional point of view, as cheese samples were rich in polyphenols, giving a high antioxidant potential. From a biochemical standpoint, we noted a slight decrease of proteolysis during ripening, whereas, according to the analysis of volatile compounds, lipolysis was the most relevant phenomenon in samples. The presence of bioactive compounds also modified the fatty acid profile of milk and cheese, leading to an increase in concentration of linoleic, vaccenic, and rumenic acids. No significant variations were found in the sensory profile. These results showed the potential of dietary grape pomace intake to influence the chemical-nutritional and nutraceutical properties of cow milk and cheeses, whose introduction to the market could be attractive to consumers, providing interesting implications for the dairy industry. Finally, our results identified of a valid use of an agro-industrial by-product, grape pomace, whose disposal generally presents economic and environmental problems.


Assuntos
Queijo/análise , Dieta/veterinária , Frutas/química , Vitis , Compostos Orgânicos Voláteis/análise , Animais , Antioxidantes/análise , Bovinos , Indústria de Laticínios , Suplementos Nutricionais/análise , Ácidos Graxos/análise , Feminino , Resíduos Industriais/análise , Ácido Linoleico/análise , Lipólise , Leite/química , Polifenóis/análise
14.
PLoS One ; 13(10): e0204212, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30303988

RESUMO

During industrial wood drying, extractives migrate towards the wood surfaces and make the material more susceptible to photo/biodegradation. The present work provides information about the distribution, quantity and nature of lipophilic substances beneath the surface in air- and kiln-dried Scots pine (Pinus sylvestris L.) sapwood boards. Samples were taken from knot-free sapwood surfaces and the composition of lipophilic extractives, phenols and low-molecular fatty/resin acids layers at different nominal depths below the surface was studied gravimetrically, by UV-spectrometry and by gas chromatography-mass spectrometry (GC-MS). The concentration of total extractives was significantly higher in kiln-dried than in air-dried samples and was higher close to the surface than in the layers beneath. The scatter in the values for the lipophilic extractives was high in both drying types, being highest for linoleic acid and slightly lower for palmitic, oleic and stearic acids. The amount of fatty acids was low in kiln-dried boards, probably due to a stronger degradation due to the high temperature employed. The most abundant resin acid was dehydroabietic acid followed by pimaric, isopimaric, and abietic acids in both drying types. It is concluded that during kiln-drying a migration front is created at a depth of 0.25 mm with a thickness of about 0.5 mm.


Assuntos
Lipídeos/análise , Pinus sylvestris/química , Madeira/análise , Cromatografia Gasosa-Espectrometria de Massas , Indústrias , Ácido Linoleico/análise , Ácidos Oleicos/análise , Ácidos Palmíticos/análise , Extratos Vegetais/análise
15.
Food Res Int ; 114: 214-222, 2018 12.
Artigo em Inglês | MEDLINE | ID: mdl-30361019

RESUMO

The effect of adding amino acids on wine aroma is largely influenced by nutritional status of grape must. In this study, the effects of linoleic acid (LA) content on the aromatic function of branched-chain amino acids (BCAAs) addition were investigated in alcoholic fermentation of Cabernet Sauvignon wine. The results showed that initial LA content in must significantly influenced the effect of BCAAs addition on volatiles in final wine. Adding BCAAs (140 mg/L of l-leucine, 117 mg/L of l-isoleucine and 118 mg/L of l-valine) in must with low LA content (12 mg/L) promoted the production of most volatiles, including higher alcohols (isobutanol, 2-phenylethanol), fatty acids (hexanoic acid, octanoic acid, decanoic acid) and esters (ethyl acetate, isoamyl acetate, 2-phenethyl acetate and ethyl octanoate), which were well consistent with previous literatures. However, this function disappeared or even became inhibition with increasing LA content in must, especially in 120 mg/L LA must, the total contents of higher alcohol, acetate esters and ethyl esters were 33.9%, 18.1% and 54.2% lower than those in the control without BCAAs addition, respectively. The transcriptional data revealed that several major genes including GAP1, ADH1, ATF1, ACC1, FAS1 and OLE1 were marked repressed by high LA content. Our data indicated that LA can regulate the expressions of related functional genes to efficiently influence the formations of volatiles in BCAAs supplemented wines. Therefore, it is essential to consider initial content of unsaturated fatty acids (LA) in must when using the strategy that supplying amino acids (BCAAs) to modulate aromatic quality of wines.


Assuntos
Aminoácidos de Cadeia Ramificada/análise , Ácido Linoleico/análise , Odorantes/análise , Vitis/química , Vinho/análise , Aminoácidos de Cadeia Ramificada/metabolismo , Fermentação , Saccharomyces cerevisiae/metabolismo , Compostos Orgânicos Voláteis/análise
16.
Appl Microbiol Biotechnol ; 102(23): 10017-10026, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30284011

RESUMO

Okara (soybean residue), a by-product from soymilk and tofu production, has a green, grassy off odour as it contains a large amount of aldehydes. This work investigated the rate-limiting enzyme(s) in the formation of aldehydes in okara and the pathways leading to their bioconversion into fruity, pleasant-smelling esters by the yeast Lindnera saturnus. Lipase and hydroperoxide lyase were shown to be rate-limiting enzymes while endogenous soy lipoxygenase was also crucial for the production of aldehydes in okara. Subsequent fermentation of okara by L. saturnus increased the amount of esters by about 70 times to 165-277 µg/g dried okara. The generation of C7 esters followed our hypothesised pathway, while that for C6 esters was mainly affected by L. saturnus. This study presents a simple and inexpensive one-pot setup for the natural bio-production of esters from okara.


Assuntos
Ésteres/metabolismo , Proteínas de Plantas/química , Polissacarídeos/química , Saccharomycetales/metabolismo , Alimentos de Soja/microbiologia , Compostos Orgânicos Voláteis/metabolismo , Aldeído Liases/metabolismo , Catálise , Sistema Enzimático do Citocromo P-450/metabolismo , Fermentação , Manipulação de Alimentos , Microbiologia Industrial , Ácido Linoleico/análise , Lipase/metabolismo , Lipoxigenase/metabolismo , Ácido alfa-Linoleico/análise
17.
J Oleo Sci ; 67(10): 1299-1306, 2018 Oct 11.
Artigo em Inglês | MEDLINE | ID: mdl-30210074

RESUMO

This study used a rice bran oil solid fat fraction (RBOSF) to produce cocoa butter alternatives via interesterification reaction catalyzed by immobilized lipase (Lipozyme® RM IM) in hexane. Effects of reaction time (6, 12, and 18 h), temperature (55, 60, and 65°C), mole ratios of 3 substrates [RBOSF:palm olein:C18:0 donors (1:1:2, 1:2:3, and 1:2:6)] were determined. The substrate system was dissolved in 3 mL of hexane and 10% of lipase was added. Two sources of C18:0 donors, stearic acid (SAd) and ethyl stearate (ESd) were used. Pancreatic lipase - catalyzed sn-2 positional analysis was also performed on both substrates and structured lipids (interesterification products). Structured lipids (SL) were analyzed by gas - liquid chromatography (G40.35LC) for fatty acid composition. Major fatty acids of RBOSF were C18:1, oleic acid (OA, 41.15±0.01%), C18:2, linoleic acid (LA, 30.05±0.01%) and C16:0, palmitic acid (PA, 22.64±0.01%), respectively. A commercial raw cocoa butter (CB) contained C18:0, stearic acid (SA, 33.13±0.04%), OA (32.52±0.03%), and PA (28.90±0.01%), respectively. Fatty acids at sn-2 position of RBOSF were OA (46.52±0.63%) and LA (42.98±1.1%), while major fatty acid at sn-2 position of CB was OA (85.24±1.22%). The RBOSF had low SA (2.40±0.01%) compared to CB (33.13±0.04%). The content of OA (46.52±0.63%) at sn-2 position in RBOSF was half of that found in CB (85.24±1.22%). Optimal reaction was 1:2:6 mole ratio of the substrate (RBOSF:PO:SAd), at 65°C for 12 h. Fatty acid compositions of the SL were 31.72±0.99% SA, 30.91±0.53% LA, 23.18±0.32% OA, and 13.26±0.34% PA, respectively. Fatty acids at sn-2 position of the SL were 53.72±4.21% OA, 25.11±3.69% LA, 14.18±1.58% PA, and 6.99±0.02% SA, respectively. DSC curves showed the melting point of CB at 20.94°C, while those of the SL were 14.15 and 40.35°C, respectively. The melting completion temperature (Tmc) of CB was 25.5°C while that of SL was 43.9°C, respectively.


Assuntos
Lipase/química , Óleo de Farelo de Arroz/química , Catálise , Esterificação , Hexanos/química , Ácido Linoleico/análise , Lipídeos/química , Ácido Oleico/análise , Ácido Palmítico/análise , Estearatos/química , Ácidos Esteáricos/química , Temperatura Ambiente , Fatores de Tempo , Temperatura de Transição
18.
Food Funct ; 9(9): 4742-4754, 2018 Sep 19.
Artigo em Inglês | MEDLINE | ID: mdl-30101962

RESUMO

There is a debate about the optimal dietary ratio of the parent n6 fatty acid linoleic acid (LA) and n3 fatty acid alpha-linolenic acid (ALA) to promote an efficient conversion of ALA to EPA and DHA, which have implications for human health. The aim of the present study was to compare the effects of a low-LA/high-ALA (loLA/hiALA) diet with a high-LA/low-ALA (hiLA/loALA) diet on fatty acid concentrations in red blood cells (RBCs). Fifteen omnivore healthy men (mean age 26.1 ± 4.5 years) with a low initial EPA/DHA status (sum (∑) EPA + DHA% of total fatty acids in RBC at baseline: 4.03 ± 0.17) received both diets for two weeks with a nine-week wash-out phase in between. Fatty acid intake of the subjects was tightly controlled. Concentrations [µg mL-1] and relative amounts [% of total fatty acids] of fatty acids in RBCs were analyzed at baseline (day 0), day 7 and 14 by means of GC-FID. The dietary LA/ALA ratios were 0.56 ± 0.27 : 1 and 25.6 ± 2.41 : 1 and led to significantly different changes of ALA, LA, EPA and ∑EPA + DHA concentrations in RBCs. In the course of the loLA/hiALA diet ALA and EPA concentrations and relative amounts of ∑EPA + DHA increased, whereas LA concentrations decreased. The DHA concentration was unaffected. The hiLA/loALA diet led to slightly decreased EPA concentrations, while all other fatty acid concentrations remained constant. Compared to our previous study, where we simply increased the ALA intake, our results show that ALA supplementation combined with a reduced LA intake (loLA/hiALA diet) more efficiently enhanced EPA blood concentrations. The absence of changes in the PUFA pattern in consequence of a LA/ALA ratio of 25.6 ± 2.41 : 1 suggests that the high LA/ALA ratio of the Western diet already leads to a saturation and a further increase of the ratio does not affect the PUFA pattern.


Assuntos
Ácidos Docosa-Hexaenoicos/análise , Ácido Eicosapentaenoico/análise , Eritrócitos/química , Eritrócitos/metabolismo , Ácido Linoleico/metabolismo , Ácido alfa-Linoleico/metabolismo , Adulto , Ácidos Docosa-Hexaenoicos/metabolismo , Ácido Eicosapentaenoico/metabolismo , Ácidos Graxos/química , Ácidos Graxos/metabolismo , Feminino , Humanos , Ácido Linoleico/análise , Masculino , Adulto Jovem , Ácido alfa-Linoleico/análise
19.
Artigo em Inglês | MEDLINE | ID: mdl-30103921

RESUMO

Based on the premise that the fatty acid composition of human milk can be substantially altered by diet, the current study investigated the fatty acid profile (fattyacidome) of breast milk in Galicia, a small region located in the north-west of Spain and characterized by the Southern European Atlantic Diet (SEAD). A cross-country comparison was also performed to assess worldwide variety and diet impact, reviewing the profiles reported various European, North and South American, Asian and African countries and Australia. Galician human milk appeared similar to the rest of Europe, with some particular features related to the SEAD (dairy, pork, beef and sunflower and olive oils), such as relatively high levels of linoleic acid and lower α-linolenic acid. The results also showed the existence of woman-specific profiles and significant changes over lactation in some fatty acids. Worldwide, the fatty acid profiles were similar, with the clear exception of Asiatic breast milk. The impact of fatty acids on infant health warrants further investigation.


Assuntos
Ácidos Graxos/análise , Comportamento Alimentar/classificação , Leite Humano/química , Adulto , Feminino , Humanos , Ácido Linoleico/análise , Fatores Sexuais , Espanha , Ácido alfa-Linoleico/análise
20.
Plant Physiol Biochem ; 130: 511-516, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-30092560

RESUMO

Suaeda salsa is an annual euhalophytic herb that produces dimorphic seeds, such as small black seeds and big brown seeds. In the present study, the fatty acid composition, content of total phenols, flavonoids, carotenoid and inorganic ions in dimorphic seeds of the species collected in the field were measured. There was no significant difference in total oil content between black and brown seeds. Seed total oil content was approximately 19% based on dry weight. The most abundant fatty acid was linoleic acid, and the content was 76.3 and 70.5% of total fatty acids in black and brown seeds, respectively. Furthermore, the contents of total phenols, flavonoids, carotenoids and inorganic ions in brown seeds were higher than those in black seeds, which might be the mechanism of higher salt tolerance of brown seeds than black seeds. The ecological, physiological and genetic mechanisms of the different abilities of nutrition accumulation in black and brown seeds of S. salsa are also discussed and worthy to be investigated in the future.


Assuntos
Chenopodiaceae/química , Sementes/química , Carotenoides/análise , Chenopodiaceae/metabolismo , Ácidos Graxos/análise , Flavonoides/análise , Compostos Inorgânicos/análise , Ácido Linoleico/análise , Fenóis/análise , Óleos Vegetais/análise , Sementes/metabolismo
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