Trihydroxyoctadecenoic Acids Research Articles

Mass spectrometry unveils heat-induced changes in yolk oxylipins and key lipid molecules during home cooking

IntroductionOxylipins, as a widespread class of metabolic markers following oxidative stress, and several studies have reported dietary regulation of lipid metabolism. However, there is a lack of investigation of dietary oxylipins, especially cooking-induced changes in food lipid oxidation. ObjectivesInvestigated the effects of cooking methods and lipid profiles on polyunsaturated fatty acids derived oxylipins generation within egg yolks. MethodsThe lipid profile of egg yolk was determined by UPLC-QTOF-MS/MS, oxylipins were detected by HPLC-QTRAP-MS/MS, while the total fatty acid content was quantified by GC-FID. Random Forest (RF) and Partial Least Squares (PLS) regression models were employed to explore the association between oxidized lipids and key lipid species. ResultsHeating reduced egg yolk docosahexaenoic acid (DHA) content, and no consistent trends for arachidonic acid (AA), linoleic acid (LA), and linolenic acid (ALA). Yolk lipid composition affected triacylglycerol (TG), phosphatidylethanolamine (PE), and LA-monoepoxide contents after cooking. 9- and 13-HODE (hydroxyoctadecadienoic acid), 9,10,13-TriHOME (trihydroxyoctadecenoic acid), 9,10- and 12,13-EpOME (epoxyoctadecenoic acid), 9,10- and 12,13-DiHOME (dihydroxyoctadecenoic acid), 5-HETE (hydroxyeicosatetraenoic acid), and 4-HDHA (hydroxydocosahexaenoic acid) were the prevalent oxylipins with high concentrations, accounting for 1.08 %–29.58 % of the total content of 29 oxylipins. Steaming resulted in a 1.9-fold increase in oxylipin concentrations in yolks compared to raw yolks, and boiling with or without shells (poaching) resulted in a 1.30- to 1.76-fold increase in oxylipin concentrations. In contrast, pan-fried yolks exhibited the lowest and least variable levels of total oxylipins, while still retaining some epoxides, including epoxyeicosatrienoic acid (EET) and EpOME. Utilizing big data analysis, we mapped the oxylipin network in both ordinary and DHA-enriched egg yolks, revealing a strong correlation between cooking-induced oxylipin production and variations in 24 lipid species. ConclusionRevealed the potential mechanisms and key lipid molecules for heating-induced oxylipin production of yolk through lipidomics and big data analysis.

Effect of fermentation on color characteristics and metabolite profiles of purple potato flour

The effect of fermentation on color characteristics and metabolite profiles of purple potato flour (PPF) were evaluated. The results showed that fermentation had a significant effect on the color attributes of samples. The bioactive compounds in PPF were identified using untargeted ultra-performance liquid chromatography with quadrupole time-of-flight mass spectrometry (UPLC-QTOF/MS). There were 63 compounds found in unfermented PPF (UF), while fermented samples showed more abundant compounds, including 69 compounds in naturally fermented PPF and 73 compounds in lactobacillus fermented PPF. The quantitative results showed that bioactive compounds with larger molecular weight decreased, but small molecules with high bioavailability increased after fermentation. The levels of caffeic acid, ferulic acid, and kaempferol in amylolytic L. plantarum CGMCC 14177 fermented PPF (ALF) were more than 3 times higher than those in UF. Foodomics analysis indicated that natural fermentation and lactobacillus fermentation had obvious differences in the conversion effect of metabolites in PPF. Based on orthogonal partial least squares discriminant analysis, 17 key bioactive compounds affected by fermentation were screened. L. plantarum CGMCC 15358 and CGMCC 14177 showed similar conversion effects on bioactive compounds, and their marker metabolites were trihydroxyoctadecenoic acid isomer 2, caffeic acid, 12,15-octadecadienoic acid methyl ester, and lactic acid.

Lipopolysaccharides from Ralstonia solanacearum induce a broad metabolomic response in Solanum lycopersicum.

Ralstonia solanacearum, one of the most destructive crop pathogens worldwide, causes bacterial wilt disease in a wide range of host plants. The major component of the outer membrane of Gram-negative bacteria, lipopolysaccharides (LPS), has been shown to function as elicitors of plant defense leading to the activation of signaling and defense pathways in several plant species. LPS from a R. solanacearum strain virulent on tomato (LPSR. sol.), were purified, chemically characterized, and structurally elucidated. The lipid A moiety consisted of tetra- to hexa-acylated bis-phosphorylated disaccharide backbone, also decorated by aminoarabinose residues in minor species, while the O-polysaccharide chain consisted of either linear tetrasaccharide or branched pentasaccharide repeating units containing α-L-rhamnose, N-acetyl-β-D-glucosamine, and β-L-xylose. These properties might be associated with the evasion of host surveillance, aiding the establishment of the infection. Using untargeted metabolomics, the effect of LPSR. sol. elicitation on the metabolome of Solanum lycopersicum leaves was investigated across three incubation time intervals with the application of UHPLC-MS for metabolic profiling. The results revealed the production of oxylipins, e.g., trihydroxy octadecenoic acid and trihydroxy octadecadienoic acid, as well as several hydroxycinnamic acid amide derivatives, e.g., coumaroyl tyramine and feruloyl tyramine, as phytochemicals that exhibit a positive correlation to LPSR. sol. treatment. Although the chemical properties of these metabolite classes have been studied, the functional roles of these compounds have not been fully elucidated. Overall, the results suggest that the features of the LPSR. sol. chemotype aid in limiting or attenuating the full deployment of small molecular host defenses and contribute to the understanding of the perturbation and reprogramming of host metabolism during biotic immune responses.

Phytochemical study of Stachys sylvatica (Lamiaceae) aerial parts

In this article, the first complete phytochemical study of Stachys sylvatica (Lamiaceae) aerial parts, collected in Tuscan-Emilian Apennine, is reported. Twenty-three known compounds were isolated from the chloroform, chloroform-methanol 9:1 and methanol extracts; they were subsequently characterized by means of one- and two-dimensional nuclear magnetic resonance spectroscopy (1D- and 2D-NMR) and mass spectrometry as six simple phenolic derivatives (chlorogenic acid (1), caffeic acid (2), p-coumaric acid methyl ester (3), niduloic acid (4), hydroxytyrosol (5), tyrosol (6)), one glycosylated aliphatic alcohol (ebracteatoside B (7)), six glycosylated phenylpropanoids (decaffeoyl verbascoside (8), lavandulifolioside (9), betanyoside F (10), verbascoside (11), isoacteoside (12), cystanoside D (13)), four flavonoids (stachyspinoside (14), chrysoeriol 7-O-β-D-glucopyranoside (15), naringenin 7-O-(6’’-E + Z-p-coumaroyl)-β-D-glucopyranoside (16), apigenin 7-O-(6’’-E + Z-p-coumaroyl)-β-D-glucopyranoside (17)), three lignans (syringaresinol 4’-O-β-D-glucopyranoside (18), pinoresinol 4-O-β-D-glucopyranoside (19), 2-episesaminol 2-O-β-D-glucopyranoside (20)) and three ionones (loliolide (21), vomifoliol (22), (3S,5R,6R,7E,9R)-3,5,6,9-tetrahydroxy-7-megastigmene (23)). In addition, a further phenolic derivative (ethyl caffeate (b)) and four carboxylic acids (azelaic acid (a), trihydroxyoctadecadienoic acid (c), trihydroxyoctadecenoic acid (d) and dihydroxydodecadienoic acid (e)) have been tentatively identified by ultra-high performance liquid chromatography coupled to an electrospray ionization source high-resolution Orbitrap mass spectrometer (UHPLC-ESI-HR-Orbitrap/MS). Chemosystematic relationships between S. sylvatica and other related species were highlighted.

Limoniastrum monopetalum-Mediated Nanoparticles and Biomedicines: In Silico Study and Molecular Prediction of Biomolecules.

An in silico approach applying computer-simulated models helps enhance biomedicines by sightseeing the pharmacology of potential therapeutics. Currently, an in silico study combined with in vitro assays investigated the antimicrobial ability of Limoniastrum monopetalum and silver nanoparticles (AgNPs) fabricated by its aid. AgNPs mediated by L. monopetalum were characterized using FTIR, TEM, SEM, and DLS. L. monopetalum metabolites were detected by QTOF-LCMS and assessed using an in silico study for pharmacological properties. The antibacterial ability of an L. monopetalum extract and AgNPs was investigated. PASS Online predictions and the swissADME web server were used for antibacterial activity and potential molecular target metabolites, respectively. Spherical AgNPs with a 68.79 nm average size diameter were obtained. Twelve biomolecules (ferulic acid, trihydroxy-octadecenoic acid, catechin, pinoresinol, gallic acid, myricetin, 6-hydroxyluteolin, 6,7-dihydroxy-5-methoxy 7-O-β-d-glucopyranoside, methyl gallate, isorhamnetin, chlorogenic acid, 2-(3,4-dihydroxyphenyl)-5,7-dihydroxy-4-oxo-4H-chromen-3-yl 6-O-(6-deoxy-β-l-mannopyranosyl)-β-d-glucopyranoside) were identified. The L. monopetalum extract and AgNPs displayed antibacterial effects. The computational study suggested that L. Monopetalum metabolites could hold promising antibacterial activity with minimal toxicity and an acceptable pharmaceutical profile. The in silico approach indicated that metabolites 8 and 12 have the highest antibacterial activity, and swissADME web server results suggested the CA II enzyme as a potential molecular target for both metabolites. Novel therapeutic agents could be discovered using in silico molecular target prediction combined with in vitro studies. Among L. Monopetalum metabolites, metabolite 12 could serve as a starting point for potential antibacterial treatment for several human bacterial infections.

Anti-inflammatory activity and metabolites profiling of aqueous stem bark extract of Ficus vogelii (Moraceae) in rats

IntroductionFicus vogelii is a terrestrial tree, used in Cameroonian pharmacopeia to treat various inflammatory diseases such as rheumatism. Accordingly, the present work aimed at evaluating anti-inflammatory potential of Ficus vogelii aqueous extract and identified phytochemicals of interest. MethodsThe characterization of the phytochemicals was carried out by HPLC-ESI-MSn. The anti-inflammatory potential of the aqueous extract of Ficus vogelii (100, 200, 400 and 600 mg/kg) was investigated using acute inflammatory models induced by chemicals, and chronic inflammatory models induced by formalin and Complete Freund Adjuvant (CFA) in rats. ResultsFicus vogelii significantly (p < 0.001) inhibited carrageenan-induced rat paw edema with maximum inhibitions of 75.86% (0.5 h), 82.41% (3 h) and 90.18% (6 h) at 100 mg/kg. This extract significantly (p < 0.001) reduced paw edema induced by histamine (54.10%), serotonin (54.06%), dextran (38.90%) and arachidonic acid (56.95%) respectively up to 1 h. Similarly, the extract significantly (p < 0.001) inhibited edema formation on the left paws of rats from day 2 up to 7 days post formalin injection, and significantly (p < 0.001) decreased paw edema of CFA-treated rats with the highest effect of 67.85% and 77.07% obtained on day 13 and day 21. Furthermore, the extract showed an antioxidant potential by improving the tissue levels of malondialdehyde, nitrites, superoxide dismutase and catalase. Phytochemicals analysis showed several compounds with isocitric acid (19%), trihydroxy-octadecenoic acid (18%), followed by dihydroxybenzoic acid, chlorogenic acid and vicenin-2 (8–9%). Oxylipins represented approximately 25% of the extract, thus being some of the compounds responsible for the observed activity. ConclusionThese results suggest that Ficus vogelii have anti-inflammatory effects on acute and chronic inflammation conditions.

Plasma Metabolomics Analysis of Aspirin Treatment and Risk of Colorectal Adenomas.

This research used metabolomics, an innovative discovery-based approach, to identify molecular changes in human blood that may help to explain how aspirin use reduces the risk of colorectal neoplasia in some individuals. Ultimately, this work could have important implications for optimizing aspirin use in the prevention of colorectal cancer.

Quantification and Bitter Taste Contribution of Lipids and Their Oxidation Products in Pea-Protein Isolates (Pisum sativum L.).

An ultra-high-performance liquid chromatography-differential ion mobility (DMS)-tandem mass spectrometry method was developed to quantify 14 bitter-tasting lipids in 17 commercial pea-protein isolates (Pisum sativum L.). The DMS technology enabled the simultaneous quantification of four hydroxyoctadecadienoic acid isomers, namely, (10E,12Z)-9-hydroxyoctadeca-10,12-dienoic acid (5), (10E,12E)-9-hydroxyoctadeca-10,12-dienoic acid (6), (9Z,11E)-13-hydroxyoctadeca-9,11-dienoic acid (7), and (9E,11E)-13-hydroxyoctadeca-9,11-dienoic acid (8). Based on quantitative data and human bitter taste recognition thresholds, dose-over-threshold factors were determined to evaluate the individual lipids' bitter impact and compound classes. The free fatty acids α-linolenic acid (10) and linoleic acid (13), as well as the trihydroxyoctadecenoic acids, especially 9,10,11-trihydroxyoctadec-12-enoic (3), and 11,12,13-trihydroxyoctadec-9-enoic acids (4), were shown to be key inducers to bitterness in the isolates. Additionally, the impact of 1-linoleoyl glycerol (9) on the bitter taste could be shown for 14 of the 17 tested pea-protein isolates.

Phytochemical Analysis, Network Pharmacology and in Silico Investigations on Anacamptis pyramidalis Tuber Extracts.

Anacamptis pyramidalis (L.) Rich. forms part of the Orchidaceae family that is highly valued for its horticultural as well as therapeutic benefits. The present study set out to investigate the inhibitory activity of A. pyramidalis tubers against key biological targets for the management of type 2 diabetes, Alzheimer disease, and skin hyperpigmentation. In addition, the antioxidant potential of the extracts was also assessed using multiple methods. The detailed phytochemical profiles of the extracts were determined using high-performance liquid chromatography. Based on qualitative phytochemical fingerprint, a network pharmacology analysis was conducted as well. Parishin was identified from the water extract only, whereas gastrodin and caffeic acid derivatives were present in the methanol extract. The methanol extract exhibited high inhibitory activity against tyrosinase (69.69 mg kojic acid equivalent/g extract), α-amylase (15.76 mg acarbose equivalent/g extract), and α-glucosidase (20.07 mg acarbose equivalent/g extract). Similarly, the methanol extract showed highest antioxidant potential (22.12, 44.23, 45.56, and 29.38 mg Trolox equivalent/g extract, for 2,2-diphenyl-1-picrylhydrazyl (DPPH), 2,2′-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS), CUPric Reducing Antioxidant Capacity (CUPRAC), and Ferric Reducing Antioxidant Power (FRAP) assays, respectively). Finally, the results of network pharmacology analysis, besides corroborating traditional uses of plant extracts in the management of cold and flu, confirmed a direct involvement of identified phytochemicals in the observed enzyme inhibitory effects, especially against tyrosinase, α-amylase, and α-glucosidase. Furthermore, based on the results of both colorimetric assays and network pharmacology analysis related to the activity of A. pyramidalis extracts and identified phytocompounds on enzymes involved in type 2 diabetes, a docking study was conducted in order to investigate the putative interactions of oxo-dihydroxy octadecenoic acid trihydroxy octadecenoic acid against aldose reductase, peroxisome proliferator-activated receptor (PPAR)-α, dipeptidyl peptidase (DPP)-IV, and α-glucosidase. Docking analysis suggested the inhibitory activity of these compounds against the aforementioned enzymes, with a better inhibitory profile shown by oxo-dihydroxy octadecenoic acid. Overall, the present findings supported the rationale for the use of A. pyramidalis as source of bioactive metabolites and highlight, today more than ever, for the strong necessity of linkage strategy between wild resource valorization and conservation policy.

Chemical composition of thermally processed coconut water evaluated by GC–MS, UPLC-HRMS, and NMR

Thermally-processed coconut water often develop a commercially-undesirable pink color, thus, NMR, UPLC-HRMS, GC–MS analyses combined with chemometrics approach were applied to evaluate chemical variations in comparison to tender water (control) that could explain such color change. Chemometrics on negative ionization mode dataset showed trimeric and A-type dimeric procyanidins, and caffeoylshikimic acid as main identified secondary metabolites induced by processing, while, control water presented mainly cytokinin trans-zeatin riboside, procyanidin dimer, caffeoylshikimic acid and trihydroxy-octadecenoic acid. Processing increased long-chain saturated palmitic and stearic fatty acids contents, meanwhile NMR analysis showed a decline in primary metabolites content as sugars fructose and glucose, and short-chain organic acids. Among the results observed for thermally processed coconut water, the increase in oligomeric procyanidins as A-type dimer and trimer may be associated with pink color development as these are precursors of anthocyanin pigment and/or by enhancing color stability of anthocyanin solutions.

Chemical characterization of small-molecule inhibitors of monoamine oxidase B synthesized from the Acanthopanax senticosus root with affinity ultrafiltration mass spectrometry.

Discovering and identifying new small-molecule inhibitors of monoamine oxidase B (MAO-B) could provide the potential to treat many neurodegenerative diseases. We employed affinity ultrafiltration liquid chromatography/tandem mass spectrometry (AUF-LC/MSn ) to identify and characterize small-molecule inhibitors of MAO-B from a 30% ethanolic extract of Acanthopanax senticosus root (ASR). In vitro tests were performed in stimulated BV2 microglia to evaluate the anti-inflammatory effects of the ASR preparation. An in vitro enzyme activity assay, measuring half-maximal inhibitory concentrations (IC50 ) against MAO-B, determined the inhibitory activity of the potential MAO-B ligands. ASR treatment significantly inhibited NO release (p <0.01) and attenuated tumor necrosis factor (TNF)-α expression in stimulated BV2 microglia. Nine compounds were isolated from the ASR preparation as potential MAO-B inhibitors, identified as quinic acid, chlorogenic acid, isofraxidin, dicaffeoylquinic acid, pinoresinol diglucoside, medioresinol 4'-O-β-D-glucopyranoside, eletutheroside E, syringaresinol O-β-D-glucoside, and trihydroxyoctadecenoic acid, based on their tandem mass spectra. Our study provides critical data on compounds from ASR extracts which are suitable for the development of new MAO-B inhibitors as potential therapeutics for neurodegenerative diseases.

Eosinophils synthesize trihydroxyoctadecenoic acids (TriHOMEs) via a 15-lipoxygenase dependent process

Trihydroxyoctadecenoic acids (TriHOMEs) are linoleic acid-derived lipid mediators reported to be dysregulated in obstructive lung disease. In contrast to many other oxylipins, TriHOME biosynthesis in humans is still poorly understood. The association of TriHOMEs with inflammation prompted the current investigation into the ability of human granulocytes to synthesize the 16 different 9,10,13-TriHOME and 9,12,13-TriHOME isomers and of the TriHOME biosynthetic pathway. Following incubation with linoleic acid, eosinophils and (to a lesser extent) the mast cell line LAD2, but not neutrophils, formed TriHOMEs. Stereochemical analysis revealed that TriHOMEs produced by eosinophils predominantly evidenced the 13(S) configuration, suggesting 15-lipoxygenase (15-LOX)-mediated synthesis. TriHOME formation was blocked following incubation with the 15-LOX inhibitor BLX-3887 and was shown to be largely independent of soluble epoxide hydrolase and cytochrome P450 activities. TriHOME synthesis was abolished when linoleic acid was replaced with 13-HODE, but increased in incubations with 13-HpODE, indicating the intermediary role of epoxy alcohols in TriHOME formation. In contrast to eosinophils, LAD2 cells formed TriHOMEs having predominantly the 13(R) configuration, demonstrating that there are multiple synthetic routes for TriHOME formation. These findings provide for the first-time insight into the synthetic route of TriHOMEs in humans and expand our understanding of their formation in inflammatory diseases.

Characterization of Bitter-Tasting Oxylipins in Poppy Seeds (Papaver somniferum L.).

Activity-guided fractionation of poppy seed (Papaver somniferum L.) extracts and analysis of fatty acid oxidation model experiments, followed by liquid chromatography time-of-flight mass spectrometry, tandem mass spectrometry, and one-/two-dimensional nuclear magnetic resonance experiments, revealed the chemical structures of five bitter-tasting fatty acids (1-5), three monoglycerides (6-8), six C18-lipidoxidation products (9-14), and four lipid oxidation degradation products (15 and 17-19) as well as two previously unreported monoglyceride oxidation degradation products, namely, 9-(2',3'-dihydroxypropyloxy)-9-oxononaic acid (1-azeloyl-rac-glycerol, 16) and 1-(2',3'-dihydroxypropyl)-8-(5″-oxo-2″,5″-dihydrofruan-2″-yl)-octonoate (1-ODFO-rac-glycerol, 20). Sensory studies exhibited low bitter taste threshold concentrations between 0.08 and 0.29 mmol/L, particularly for the higher oxidated C18-fatty acids trihydroxyoctadecenoic acid (THOE, 12), 12,13-dihydroxy-9-oxo-10-octadecenoic acid (12,13-diOH-9-oxo, 13), and 9,10-dihydroxy-13-oxo-11-octadecenoic acid (9,10-diOH-13-oxo, 14) as well as for the lipidoxidation degradation products 4-hydroxy-2-noneic acid (4-HNA, 17), 4-hydroxy-2-docecendienoic acid (HDdiA, 18), and 8-(5'-oxo-2',5'-dihydrofuran-2'-yl)-octanoic acid (ODFO, 20).

An LC-MS/MS workflow to characterize 16 regio- and stereoisomeric trihydroxyoctadecenoic acids[S

Trihydroxyoctadecenoic acids (TriHOMEs) are linoleic acid-derived oxylipins with potential physiological relevance in inflammatory processes as well as in maintaining an intact skin barrier. Due to the high number of possible TriHOME isomers with only subtle differences in their physicochemical properties, the stereochemical analysis is challenging and usually involves a series of laborious analytical procedures. We herein report a straightforward analytical workflow that includes reversed-phase ultra-HPLC-MS/MS for rapid quantification of 9,10,13- and 9,12,13-TriHOME diastereomers and a chiral LC-MS method capable of resolving all sixteen 9,10,13-TriHOME and 9,12,13-TriHOME regio- and stereoisomers. We characterized the workflow (accuracy, 98-120%; precision, coefficient of variation ≤6.1%; limit of detection, 90-98 fg on column; linearity, R2 = 0.998) and used it for stereochemical profiling of TriHOMEs in bronchoalveolar lavage fluid (BALF) of individuals with chronic obstructive pulmonary disease (COPD). All TriHOME isomers were increased in the BALF of COPD patients relative to that of smokers (P ≤ 0.06). In both COPD patients and smokers with normal lung function, TriHOMEs with the 13(S) configuration were enantiomerically enriched relative to the corresponding 13(R) isomers, suggesting at least partial enzymatic control of TriHOME synthesis. This method will be useful for understanding the synthetic sources of these compounds and for elucidating disease mechanisms.

Breeding of lipoxygenase-1-less malting barley variety ‘SouthernStar’ and evaluation of malting and brewing quality

The lipoxygenase-1-null (LOX-less) trait has positive effects on beer quality, and in particular, improvement of flavor stability by reduction of beer deteriorating substances such as trans-2-nonenal (T2N). ’SouthernStar’ was successfully developed as the first LOX-less malting barley variety in Australia by introducing LOX-less trait into ‘Flagship’ by successive backcross and molecular marker assisted selection (MMAS). ‘Flagship’ is a two-rowed malting barley variety in Australia and it was used as the recurrent parent for the successive backcrossing. The yield potential, agronomic performance, disease resistance and the general malting quality were almost identical between ‘SouthernStar’ and ‘Flagship’. To evaluate effects of LOX-less trait on beer quality, the brewing trials were conducted using a pilot-scale brewing apparatus. The wort and beer quality were similar between ‘SouthernStar’ and ‘Flagship’. The effect of the LOX-less trait on the reduction of beer deteriorating substances such as T2N and trihydroxyoctadecenoic acid (THOD) contents was clearly verified in this study. The scores for total staleness of the test beers were significantly lower than those of the control beers under several storage conditions in one trial.

Utilization of the ethyl acetate fraction of Zanthoxylum rhetsa bark extract as an active ingredient in natural sunscreen formulations

Sunburn, premature skin aging, skin cancers and suppression of the immune system are linked to exposure of the skin to UV light. In recent years, plant extracts are becoming a popular active ingredient in natural sunscreen formulations. In the present study, the ethyl acetate fraction of Zanthoxylum rhetsa bark (commonly called as Indian prickly Ash) was used as an active ingredient in two sunscreen cream formulations (F1 and F2). Primarily, the constituents present in the active fraction were identified using LC–MS/MS analysis. Coumaric acid, benzoic acid, p-hydroxybenzoic acid and its isomers, hesperitin, trihydroxyoctadecenoic acid and columbamine were identified in the ethyl acetate fraction of Z. rhetsa bark extract. The UV protection properties of the formulated creams were evaluated by assessment of parameters such as their SPF values (F1: 3.60±0.28, F2: 6.90±0.57), UVA effectiveness (moderate for both test formulations) and critical wavelengths (F1: 365.4, F2: 360.3). Moreover, the physicochemical and microbial count of the formulated creams was also assessed based on various parameters such as colour, pH, centrifugation, viscosity and microbial load over a storage period of 28 days. Both formulations showed pseudo plastic behaviour and were stable at all conditions except for samples kept at 40°C. Altogether, these results suggested that the ethyl acetate fraction of Z. rhetsa bark has great potential to reduce exposure to harmful UVA/UVB radiations and may be utilized as an active ingredient in natural sunscreen formulation.

Antiamnesic Effect of Broccoli (Brassica oleracea var. italica) Leaves on Amyloid Beta (Aβ)1-42-Induced Learning and Memory Impairment.

To examine the antiamnesic effects of broccoli (Brassica oleracea var. italica) leaves, we performed in vitro and in vivo tests on amyloid beta (Aβ)-induced neurotoxicity. The chloroform fraction from broccoli leaves (CBL) showed a remarkable neuronal cell-protective effect and an inhibition against acetylcholinesterase (AChE). The ameliorating effect of CBL on Aβ1-42-induced learning and memory impairment was evaluated by Y-maze, passive avoidance, and Morris water maze tests. The results indicated improving cognitive function in the CBL group. After the behavioral tests, antioxidant effects were detected by superoxide dismutase (SOD), oxidized glutathione (GSH)/total GSH, and malondialdehyde (MDA) assays, and inhibition against AChE was also presented in the brain. Finally, oxo-dihydroxy-octadecenoic acid (oxo-DHODE) and trihydroxy-octadecenoic acid (THODE) as main compounds were identified by quadrupole time-of-flight ultraperformance liquid chromatography (Q-TOF UPLC-MS) analysis. Therefore, our studies suggest that CBL could be used as a natural resource for ameliorating Aβ1-42-induced learning and memory impairment.

Overexpression of hydroperoxide lyase, peroxygenase and epoxide hydrolase in tobacco for the biotechnological production of flavours and polymer precursors

Plants produce short-chain aldehydes and hydroxy fatty acids, which are important industrial materials, through the lipoxygenase pathway. Based on the information that lipoxygenase activity is up-regulated in tobacco leaves upon infection with tobacco mosaic virus (TMV), we introduced a melon hydroperoxide lyase (CmHPL) gene, a tomato peroxygenase (SlPXG) gene and a potato epoxide hydrolase (StEH) into tobacco leaves using a TMV-based viral vector system to afford aldehyde and hydroxy fatty acid production. Ten days after infiltration, tobacco leaves infiltrated with CmHPL displayed high enzyme activities of 9-LOX and 9-HPL, which could efficiently transform linoleic acid into C(9) aldehydes. Protein extracts prepared from 1 g of CmHPL-infiltrated tobacco leaves (fresh weight) in combination with protein extracts prepared from 1 g of control vector-infiltrated tobacco leaves (as an additional 9-LOX source) produced 758 ± 75 μg total C(9) aldehydes in 30 min. The yield of C(9) aldehydes from linoleic acid was 60%. Besides, leaves infiltrated with SlPXG and StEH showed considerable enzyme activities of 9-LOX/PXG and 9-LOX/EH, respectively, enabling the production of 9,12,13-trihydroxy-10(E)-octadecenoic acid from linoleic acid. Protein extracts prepared from 1 g of SlPXG-infiltrated tobacco leaves (fresh weight) in combination with protein extracts prepared from 1 g of StEH-infiltrated tobacco leaves produced 1738 ± 27 μg total 9,12,13-trihydroxy-10(E)-octadecenoic acid isomers in 30 min. The yield of trihydroxyoctadecenoic acids from linoleic acid was 58%. C(9) aldehydes and trihydroxy fatty acids could likely be produced on a larger scale using this expression system with many advantages including easy handling, time-saving and low production cost.

Thermostable lipoxygenase is a key enzyme in the conversion of linoleic acid to trihydroxy-octadecenoic acid by Pseudomonas aeruginosa PR3

Lipoxygenases (LOXs) constitute a family of lipid-peroxidizing enzymes that catalyze the oxidation of unsaturated fatty acid containing a (1Z,4Z)-pentadiene structural unit, leading to formation of conjugated (Z,E)-hydroperoxydienoic acid. LOXs are known to be widely distributed in plants and animals. Recently, several microbial LOXs were reported to be involved in the production of hydroperoxy fatty acids. Among the microorganisms that produce hydroxy fatty acids, Pseudomonas aeruginosa PR3 is known to convert linoleic acid to trihydroxy fatty acid, which suggests the involvement of a LOX enzyme. Based on these reports, we identified a novel thermostable LOX from P. aeruginosa PR3 strain. The protein was purified 34.3-fold with a recovery rate of 5.14%. The Km and Vmax values of the purified enzyme were 3.57 mM and 0.73 μmol/min//mg, respectively. Heat stability of the purified enzyme was unexpectedly high with an LD50 of 90 min at 80°C, although P. aeruginosa PR3 is known as a mesophilic bacterium. Substrate specificity of the purified enzyme was restricted only to unsaturated fatty acids carrying a (1Z,4Z)-pentadiene unit.

Brewing Performance of Malted Lipoxygenase‐1 Null Barley and Effect on the Flavor Stability of Beer

ABSTRACTWe examined the malting and brewing performances of a lipoxygenase‐1 (LOX‐1) null line of barley (Hordeum vulgare L.). The LOX‐normal malt and the LOX‐null malt were prepared from F4 populations derived from a single cross. We could not observe any major differences in the general malt characteristics between the two malts. A brewing trial was performed using these malts. The analysis of the wort and beer revealed that the absence of LOX‐1 had little effect on the general characteristics of the wort and beer. In contrast, beer made from the LOX‐null malt showed reduced levels of beer‐deteriorating substances, trans‐2‐nonenal (T2N), and trihydroxyoctadecenoic acid (THOD). In the sensory evaluation, well‐trained panel members recognized the significant superiority of the aged LOX‐null beer in terms of staleness. These results show that the LOX‐1 null barley line can be effectively used to improve the flavor stability of beer without changing the other important beer qualities.