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Hokkaido-specific malting barley varieties have been developed to improve the grain yield, disease resistance, malting quality, and brewing quality. In this report we describe the breeding and evaluation of brewing quality of a hulled two-row malting barley (Hordeum vulgare L.) variety 'Satuiku 5 go' lacking lipoxygenase-1 (LOX-1-less). 'Satuiku 5 go' was evaluated in the joint field trials for malting barley in Hokkaido from 2016 to 2018. 'Satuiku 5 go' exhibited 11% higher grain yield and 7.6 cm shorter plant height than the control variety, 'Ryohfu'. However, the disease severity of Fusarium head blight (FHB) in 'Satuiku 5 go' was higher than in 'Ryohfu'. For malting quality, 'Satuiku 5 go' exhibited higher diastatic power, soluble nitrogen content, and fine extract content, and lower wort ß-glucan content than 'Ryohfu'. 100-litter pilot scale brewing trials were conducted with 'Satuiku 5 go' and 'Satuiku 2 go' as a control variety, also a LOX-1-less variety, and no clear differences were observed. [ABSTRACT FROM AUTHOR]

AIM: To investigate the regulation of lipoxygenase (LOX)-1 and Dectin-1 on interleukin-10 (IL-10) production in mice with Aspergillus fumigatus (A. fumigatus) keratitis. METHODS: The corneas of C57BL/6 mice were pretreated with LOX-1 inhibitor Poly(I) or Dectin-1 siRNA separately before the infection of A. fumigatus. Polymerase chain reaction (PCR) and Western blot were used to detect the expression of IL-10. RESULTS: The mRNA and protein expressions of IL-10 were significantly increased in mice with A. fumigatus keratitis. Compared with the group pretreated with sterile water before infection, Poly(I) pretreatment suppressed IL-10 expression significantly. Compared with the group pretreated with scrambled siRNA before infection, Dectin-1 siRNA pretreatment significantly reduced IL-10 expression in response to A. fumigatus infection. CONCLUSION: LOX-1 and Dectin-1 regulate IL-10 production in mouse A. fumigatus keratitis.

Various types of malt quality profiles have been investigated to benefit the North American brewing industry. Herein, we report the development and brewing quality of the hulled, two-row malting barley (Hordeum vulgare L.) variety 'CDC Goldstar' lacking lipoxygenase-1 (LOX-1-less). This new variety offers a novel malt type for the improvement of beer flavor stability. The agronomic performance of 'CDC Goldstar' was tested in the Western Cooperative Two Row Barley Registration Trials during 2013-2014. In addition to high lodging tolerance, the new variety showed 6% higher yield than the current leading variety 'CDC Copeland'. The malt quality of 'CDC Goldstar' showed higher diastatic power and lower wort ß-glucan content than 'CDC Copeland' and controllable proteolytic modification (soluble nitrogen and Kolbach Index). Pilot- (100 L) and commercial-scale (5,000 L) brewing trials were conducted using 'CDC PlatinumStar', another LOX-1-less variety with a low enzymatic profile, as the control variety. Absence of the LOX-1 trait from 'CDC Goldstar' maintained trans-2-nonenal levels in aged beers as low as those in other LOX-1-less varieties without affecting major beer parameters, such as ester and aldehyde content or foam stability. The newly developed 'CDC Goldstar' malting barley provides added value for the beer industry and consumers. [ABSTRACT FROM AUTHOR]

Abstract 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. Highlights • A new lipoxygenase-1-less (LOX-less) malting barley variety 'SouthernStar' developed by backcrossing. • Similar agricultural characteristics and malting quality as a recurrent parent 'Flagship'. • Reduction of trihydroxyoctadecenoic acid (THOD) and trans -2-nonenal (T2N) contents in beer by LOX-less trait introduced. • Improvement of flavor stability evaluated by sensory analysis for stale beer. [ABSTRACT FROM AUTHOR]

The lipoxygenase‐1‐less (LOX‐less) trait has positive effects on beer quality, in particular, improvement of flavour stability related to the reduction of beer‐deteriorating substances such as trans‐2‐nonenal. ‘Ryohfu’ is the only spring‐sown malting barley variety grown in Hokkaido, located in the northern part of Japan, and has been used in the Japanese brewing industry for over 20 years. ‘Satuiku 2 go’ was developed as the first LOX‐less malting barley variety in Japan by successive back‐crossing with molecular marker‐assisted selection to introduce the LOX‐less trait into the recurrent parent ‘Ryohfu’. The agronomic performance and general malt quality of ‘Satuiku 2 go’ were almost equivalent to those of ‘Ryohfu’. Wort and beer analyses at the pilot‐scale brewing trial indicated that the LOX‐less trait had little effect on the general characteristics. In contrast, the beers made from ‘Satuiku 2 go’ malt exhibited reduced levels of trans‐2‐nonenal and trihydroxyoctadecenoic acid. The sensory evaluation demonstrated the superiority of ‘Satuiku 2 go’ beers stored under differing conditions in terms of staleness. It can be concluded that the LOX‐less trait was effective in different genetic backgrounds of the recurrent parents used for the development of LOX‐less malting barley varieties. Copyright © 2018 The Institute of Brewing & Distilling [ABSTRACT FROM AUTHOR]

Lipoxygenase-1 (LOX-1) null 'New Sachiho Golden' is a two-row malting barley (Hordeum vulgare L.) cultivar released in 2015 that was developed at the Tochigi Prefectural Agricultural Experimental Station by backcross breeding using the high-yield leading cultivar 'Sachiho Golden' as a recurrent parent and the LOX-1 null mutant 'Daikei LM1' as a non-recurrent parent. To develop 'New Sachiho Golden' we used a simple LOX activity assay and marker-assisted selection. This is the first LOX-1 null malting barley cultivar in Japan that is resistant to barley yellow mosaic virus (types I-III). Agronomic characteristics and malting qualities of 'New Sachiho Golden' were similar to those of 'Sachiho Golden', except that 'New Sachiho Golden' had no LOX activity in ungerminated grains and had clearly lower LOX activity during malting than 'Sachiho Golden'. The concentrations of a trans-2-nonenal (T2N) precursor in wort and beer made from 'New Sachiho Golden' were significantly lower than in those made from 'Sachiho Golden', both before and after storage. [ABSTRACT FROM AUTHOR]

Background Lipoxygenases are a family of enzymes which catalyse the hydroperoxidation of polyunsaturated fatty acids with a cis, cis-1,4-pentadiene to form conjugated hydroperoxydienes. Lipoxygenase-1 (LOX-1) in barley worsens the flavour and foam stability of beer. It has become a major selection criteria for malting quality in the last few years. Results Lipoxygenase activity was investigated in 41 Australian barley cultivars and advanced breeding lines released since the 1950s; the cultivars differed markedly, ranging from 22.3 to 46.5 U/g. The structural gene and its promoter of lipoxygenase-1 were sequenced from the barley varieties representing different levels of LOX. Based on the analysis of nucleotide and deduced amino acid sequences, two major haplotypes were identified. Barley varieties with lower LOX were classified into three categories based on their pedigrees and sequence variations in the structural gene: (1) barley varieties derived from Canadian varieties with the pre-harvest sprouting susceptible allele, (2) Skiff and Hindmarsh with unique haplotype in the structural gene, and (3) Gairdner and Onslow with an unknown mechanism. Conclusion Lipoxygenase activity has been reduced in the malting barley cultivars in the last 60 years although it is only recognized as a malting quality trait recently. There are clear haplotypes of the lipoxygenase structual gene. The polymorphisms detected in the structural gene can be used to design molecular markers for selection of low LOX haplotype. Other mechanisms also existed for controlling lipoxygenase activity. The results suggest that it is possible to develop barley varieties with lower LOX by combination of low LOX-1 haplotype and other trans-regulation factors. [ABSTRACT FROM AUTHOR]

This work was aimed at allelic status identification of the barley genes Bmy1 and LOX-1 in the collection, consisted of 103 domestic and foreign cultivars, and also selection lines. Research of the collection was held using polymerase chain reaction (PCR) with a subsequent analysis of gene LOX-1 allelic polymorphism via restriction of amplification products. Results of the PCR and restriction were visualized using gel-electrophoresis method. It was defined that 63 barley cultivars would be promising for brewing because of their middle activity and thermostability of β-amylase in malt. There was not a single cultivar or selection line with allele loxA, which was responsible for non-active type of lipoxygenase enzyme in beer, in the barley collection. Obtained results indicate low frequency of brewing alleles' occurrence. Further searching with the help of the newest molecular markers for allelic diversity identification of genes Bmy1 and LOX-1, and, additionally, expansion of the general collection of barley cultivars and selection lines, will allow better differentiation of cultivars and choose among them the most advantageous ones that will become raw material for quality beer. [ABSTRACT FROM AUTHOR]

Off-flavour generated in soy products is ascribed to soybean seed lipoxygenase-1, lipoxygenase-2 and lipoxygenase-3, controlled by single dominant genes Lox1, Lox2 and Lox3, respectively. Lox2 locus has already been mapped and reported to be tightly linked with Lox1 locus. The objective of the present study was to map Lox1 locus by investigating the SSR markers reported to be linked with Lox2 locus and the neighbouring SSR markers in two mapping populations of 116 and 91 plants developed from LSb1 × PI408251 and JS335 × PI408251, respectively. Parental polymorphism was surveyed using SSR markers Sat_074, Satt522 reported to be linked with Lox2 locus and the SSR markers in its proximity. F seeds were used for assaying lipoxygenase-1 to identify the genotype of the F individuals. SSR marker Satt656 was found to be tightly linked with Lox1 locus at distance of 3.6 and 4.8 cM in the mapping population of LSb1 × PI408251 and JS335 × PI408251, respectively. SSR marker Satt656 can be useful for marker assisted selection for transferring recessive allele of lipoxygenase-1 in the background of high yielding soybean genotypes. [ABSTRACT FROM AUTHOR]

Abstract: Durum wheat (Triticum turgidum) is the cereal of preference for semolina and pasta production. Bright yellow color, which is desirable for pasta making, depends on the amount of carotenoid pigments present in the grain. Lipoxygenases (LPXs) account for most of the carotenoid degradation activity. Although B genome Lpx genes have been extensively described, little information about the A genome has been reported. Here, we demonstrate that the Lpx-A1 locus is represented by a single gene in the diploid Triticum urartu, the tetraploid T. turgidum and the hexaploid Triticum aestivum wheats in contrast to the multiple copies reported in the B genome. The Lpx-A1_like pseudogene previously identified in T. turgidum genome A was also identified in the T. aestivum cv Chinese Spring wheat, whereas T. urartu possesses a complete copy, suggesting that pseudogenization occurred after the formation of the tetraploid and then passes to the hexaploid wheat. The nucleotide sequence of T. urartu Lpx is more closely related to genome B Lpx-1 than to Lpx genes of genome A from T. turgidum and T. aestivum, probably due to the deletions and insertions that occur. Thus, the present paper extends our knowledge of lipoxygenase gene organization and evolution in the wheat A genome. [Copyright &y& Elsevier]

Luteolin, isolated from the seeds of Perilla frutescens (perilla seeds), inhibited the peroxidation of linoleic acid catalyzed by soybean lipoxygenase-1 (EC 1.13.11.12, Type 1) with an IC of 5.0 M (1.43 μg/mL) noncompetitively. The progress curves for an enzyme reaction indicate that luteolin shows slow binding kinetics. Both the initial velocity and steady-state rate in the progress curve were decreased with increasing the concentration of luteolin. The kinetic parameters, which described the inhibition by luteolin, were evaluated by nonlinear regression fits. [ABSTRACT FROM AUTHOR]

To understand the diversity in the thermostability of the seed lipoxygenase-1 (LOX-1), 1040 cultivars of worldwide barley ( Hordeum vulgare ssp. vulgare) genetic resources were investigated. The relative thermostability of LOX-1 (LOX-RTS) in these lines showed a bimodal frequency distribution and these lines were categorized into the high and low thermostability types (H-type and L-type, respectively). The H-type lines predominated in the wild progenitor, ssp. spontaneum. The geographical distribution of these types in the cultivars was surveyed. The frequencies of the H- and L-types were almost equal to one another in southwestern Asia. The occurrence of the H-type predominated in eastern Asia and Africa, whereas in Europe and Turkey, the L-type did. The predominance of the L-type in Europe and Turkey can be understood through the hypothesis that the Fertile Crescent domestication contributed the majority of diversity in Europe. The uneven geographical distribution of the LOX-1 thermostability types in the cultivars may reflect a polyphyletic origin of barley. [ABSTRACT FROM AUTHOR]

Barley lipoxygenase (LOX)-1 is believed to affect the stability of flavour and the foam of beer. The purpose of this study was to investigate the genetic variation of the LOX-1 thermostability, and to analyse the mode of inheritance of this trait. A simple method was established to evaluate the LOX-1 relative thermostability (LOX-RTS). With this method, 153 barley cultivars were screened for LOX-RTS. The frequency of the LOX-RTS values was distributed in a bimodal manner. Based on these values, the barley lines were categorized into two groups: an H-type with relatively thermostable LOX-1 and an L-type with relatively thermolabile LOX-1. Using a ‘Steptoe’/‘Morex’ doubled haploid population, a major quantitative trait locus (QTL) associated with LOX-RTS was identified on chromosome 4H of barley, explaining 82% of the variance. Mapping of a CAPS marker specific for the LoxA locus revealed co-segregation with this QTL. In this study, the existence of the thermostability types of barley seed LOX-1 and the locus controlling the thermostability were made clearer. [ABSTRACT FROM AUTHOR]

This study describes the discovery and characterization of lipoxygenase-1 (LOX-1) null mutants in barley. Six lines did not exhibit any significant LOX activity in the silenced seed extract. Immunological analysis showed that these lines lacked the authentic LOX-1 protein. Genetic analysis of the F2 population revealed that this trait was governed by a single recessive gene located at the LoxA locus on chromosome 4H. The six LOX-1 null mutants shared similar features and the same unique polymorphism in a structural gene region, implying that these mutants might be derived from the same ancestral origin. [ABSTRACT FROM AUTHOR]

The subcellular localization of lipoxygenase-1 and-2 in the cytoledons of germinating soybean seeds [ Glycine max (L.) Merr. AmSoy] and seedlings was investigaed by direct labeling with immnogold complexes. Both lipoxygenase-1 and-2 were localized in the cytoplasm of all cotyledon cells. No gold labeling was observed on mitochondria, glyoxysomes, protein bodies, lipid bodies, or other organelles. [ABSTRACT FROM AUTHOR]

The linoleic acids embedded in the SUVs of soy-PC, DMPC, and DPPC served as substrate for soybean lipoxygenase-1 (L-1). The initial velocity of the catalytic reaction and the concentration of the substrate showed a hyperbolic relation. The Km values of L-1 for the linoleic acids in soy-PC, DMPC, and DPPC vesicles were 0.07, 0.09, and 0.11 mM, respectively, being comparable with that for Tween-20 micellar linoleic acid. Soy-PC and DMPC competitively inhibited the enzyme with K1 values of 0.20 and 0.13 mM, respectively, whereas DPPC had no effect. DSC analysis revealed the phase separation of linoleic acid and DPPC in vesicles in the temperature range in which the enzyme reaction was carried out. This may account for the lack of inhibitory effect of DPPC on the enzyme. From the temperature dependence of the specific activity of the enzyme, the Ea values of the catalytic reaction were estimated to be 26.7 and 35.3 kJ.mol−1 for soy-PC and DPPC vesicles, respectively. For linoleic acid-DMPC vesicles, a two-phase temperature dependence of the activity across the transition temperature of the mixed vesicles was suggested. [ABSTRACT FROM AUTHOR]