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Histamine (HIST) and other biogenic amines found in fish and fishery products accumulated by the action of bacterial amino acid decarboxylase cannot be decomposed and eliminated by heating or other chemical methods. A simple method for HIST elimination is proposed by a coupling reaction of the fungal amine oxidase (FAO) and bacterial aldehyde oxidase (ALOX) of acetic acid bacteria. As a model reaction, FAO oxidized benzylamine to benzaldehyde, which in turn was oxidized spontaneously to benzoic acid with ALOX. Likely, in HIST elimination, FAO coupled well with ALOX to produce imidazole 4-acetic acid from HIST with an apparent yield of 100%. Imidazole 4-acetaldehyde was not detected in the reaction mixture. In the absence of ALOX, the coupling reaction was incomplete given a number of unidentified substances in the reaction mixture. The proposed coupling enzymatic method may be highly effective to eliminate toxic amines from fish and fishery products.

The aim of this study was to propose an alternative route for preparing chiral β- and α-ionols by asymmetric oxidation with a heme acquisition system A (HasA) derived from symbiotic fluorescent bacteria as a biocatalyst. The HasA (6 g) in distilled water (300 mL) was stirred at 1150 rpm for 1 day at 40°C. Subsequently, a secondary alcohol (0.77 mmol) as a substrate in 2% 2-propanol was added to the catalyst solution. After verifying that the oxidation proceeded to ca 50% using gas chromatography (GC), the reaction mixture was filtered, extracted, washed, and dried over. The extract was concentrated in vacuo and purified using silica gel column chromatography to yield the oxidized product and recover the unreacted alcohol. β-Ionol was oxidized into β-ionone in a conversion of ca. 50% in the presence of the HasA for three days, and the remaining alcohol was recovered and analyzed using chiral GC after acetylation. The HasA selectively catalyzed the asymmetric oxidation of β-ionol with a preference for the (R)- form to recover (S)-β-ionol with 96.4 ±1.6% enantiomeric excess (ee). In addition, α-ionol was similarly oxidized into α-ionone in a conversion of ca. 50% for seven days, preferentially remaining (9S)-α-ionol with 97.9 ± 0.2% ee. The characteristic aroma of (S)-β-ionol obtained by the asymmetric oxidation with the HasA showed floral and fruity like, while the aroma of (9S)-α-ionol described as violet and sweet. In this study, we successfully developed a new approach to prepare enantiomerically pure (S)-β- and α-ionols by the asymmetric oxidation with the HasA.

d-Mannose isomerase (EC 5.3.1.7) catalyzing reversible conversion between d-mannose and d-fructose was found in acetic acid bacteria. Cell fractionation confirmed the enzyme to be a typical membrane-bound enzyme, while all sugar isomerases so far reported are cytoplasmic. The optimal enzyme activity was found at pH 5.5, which was clear contrast to the cytoplasmic enzymes having alkaline optimal pH. The enzyme was heat stable, and the optimal reaction temperature was observed at around 40-60 °C. Purified enzyme after solubilization from membrane fraction showed the total molecular mass of 196 kDa composing of identical 4 subunits of 48 kDa. Washed cells or immobilized cells were well functional at nearly 80% of conversion ratio from d-mannose to d-fructose and reversely 20%-25% of d-fructose to d-mannose. Catalytic properties of the enzyme were discussed with respect to the biotechnological applications to high fructose syrup production from konjac taro.

This work aims to propose a pathway for the production of 2(E),4(E)-decadienal from arachidonic acid (ARA) via 11-hydroperoxide eicosanoid (11 hydroperoxyeicosatetraenoic acid, 11-HPETE) through lipoxygenase (LOX) and hydroperoxide lyase (HPL) in the brown alga, Saccharina angustata, by identifying pathway intermediates through three studies. The first study investigated the biogeneration of 2(E),4(E)-decadienal in crude homogenates of fronds (CHF), while the second and third investigated whether ARA is the precursor of the pathway and if 11-HPETE is produced from ARA as an intermediate in 2(E),4(E)-decadienal generation, respectively. The results showed that 2(E),4(E)-decadienal was formed in CHF and its concentration increased after incubation. This finding led to the hypothesis that 2(E),4(E)-decadienal is formed enzymatically via LOX-HPL and consequently its biogeneration was determined. ARA was indicated to be a precursor of the pathway since, after CHF was incubated with ARA as a substrate, the amount of aldehyde increased significantly compared with that produced by CHF without ARA and without incubation. The production of 11-HPETE from ARA was also demonstrated as an intermediate reaction in 2(E),4(E)-decadienal formation via the LOX-HPL pathway. The hydroxy isomer of 11-HPETE was produced, and ARA was incubated with homogenated fronds in combination with glutathione peroxidase and glutathione to control its stability during identification. The compound was identified as 11-HPETE because the purified isomer showed the same retention time when co-injected with the standard using an HPLC technique; moreover, the same indicated mass spectrum was obtained as that of the standard via a GC/GCMS technique. The indicated pathway and the pathway for the production of short chain aldehydes [n-hexanal, 2(E),3(Z)-nonenal and 2(E),4(E)-decadienal] from ARA and linoleic acid through theirs hydroperoxides are proposed.

Due to the indigestibility, utilization of konjac taro, Amorphophallus konjac has been limited only to the Japanese traditional konjac food. Koji preparation with konjac taro was examined to utilize konjac taro as a source of utilizable carbohydrates. Aspergillus luchuensis AKU 3302 was selected as a favorable strain for koji preparation, while Aspergillus oryzae used extensively in sake brewing industry was not so effective. Asp. luchuensis grew well over steamed konjac taro by extending hyphae with least conidia formation. Koji preparation was completed after 3-day incubation at 30°C. D-Mannose and D-glucose were the major monosaccharides found in a hydrolyzate giving the total sugar yield of 50 g from 100 g of dried konjac taro. An apparent extent of konjac taro hydrolysis at 55°C for 24 h seemed to be completed. Since konjac taro is hydrolyzed into monosaccharides, utilization of konjac taro carbohydrates may become possible to various products of biotechnological interest. Fil: Adachi, Osao. Yamaguchi University; Japón Fil: Hours, Roque Alberto. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Centro de Investigación y Desarrollo en Fermentaciones Industriales. Universidad Nacional de La Plata. Facultad de Ciencias Exactas. Centro de Investigación y Desarrollo en Fermentaciones Industriales; Argentina Fil: Akakabe, Yoshihiko. Yamaguchi University; Japón Fil: Arima, Hideyuki. Yamaguchi Prefectural Industrial Technology Institute; Japón Fil: Taneba, Rie. Yamaguchi Prefectural Industrial Technology Institute; Japón Fil: Tanaka, Junya. Yamaguchi Prefectural Industrial Technology Institute; Japón Fil: Kataoka, Naoya. Yamaguchi University; Japón Fil: Matsushita, Kazunobu. Yamaguchi University; Japón Fil: Yakushi, Toshiharu. Yamaguchi University; Japón

Gluconobacter frateurii CHM 43 have D-mannitol dehydrogenase (quinoprotein glycerol dehydrogenase) and flavoprotein D-fructose dehydrogenase in the membranes. When the two enzymes are functional, D-mannitol is converted to 5-keto-D-fructose with 65% yield when cultivated on D-mannitol. 5-Keto-D-fructose production with almost 100% yield was realized with the resting cells. The method proposed here should give a smart strategy for 5-keto-D-fructose production., Centro de Investigación y Desarrollo en Fermentaciones Industriales

Due to the indigestibility, utilization of konjac taro

CHM 43 have D-mannitol dehydrogenase (quinoprotein glycerol dehydrogenase) and flavoprotein D-fructose dehydrogenase in the membranes. When the two enzymes are functional, D-mannitol is converted to 5-keto-D-fructose with 65% yield when cultivated on D-mannitol. 5-Keto-D-fructose production with almost 100% yield was realized with the resting cells. The method proposed here should give a smart strategy for 5-keto-D-fructose production.

The aim of this work was to study the physicochemical and kinetic properties of chlorogenate hydrolase (CHase) (EC 3.1.1.42) of Aspergillus niger AKU 3302 by induction in the presence of yerba mate extract. The data obtained could be applicable directly to mass processing for a plant scale production of quinic acid (QA) and caffeic acid (CA) with koji CHase. It is fundamentally significant to accumulate catalytic properties of CHase as much as possible with crude CHase, when koji CHase is directed to practical industrial processing of breakdown of chlorogenate (CGA). CHase exhibited a high thermal stability without appreciable loss after standing for 6 h at 50 °C and was stable in wide pH ranges from 2.0 to 9.0. The optimum pH and temperature of CHase activity were found at 6.5–7.0 and 45 °C, respectively. The Vmax and Km values for CGA hydrolysis were 1.996 unit mg−1 and 0.72 mM, respectively. The activation energy of CHase was estimated to be 26 kJ mol−1. Thus, CHase induced with CGA revealed successful for the production of CA and QA, fine chemicals of high interest and commercial values, from natural plant resources rich in CGA such as yerba mate. Several advantageous merits obtained with a crude CHase for the practical formation of QA and CA from yerba mate or yerba mate extract are discussed. Fil: Butiuk, Ana Paula. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Centro de Investigación y Desarrollo en Fermentaciones Industriales. Universidad Nacional de La Plata. Facultad de Ciencias Exactas. Centro de Investigación y Desarrollo en Fermentaciones Industriales; Argentina. Universidad Nacional de Misiones. Facultad de Ciencias Exactas, Químicas y Naturales; Argentina Fil: Maidana, Silvana Andrea. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Nordeste; Argentina. Universidad Nacional de Misiones. Facultad de Ciencias Exactas, Químicas y Naturales; Argentina Fil: Martos, María Alicia. Universidad Nacional de Misiones. Facultad de Ciencias Exactas, Químicas y Naturales; Argentina Fil: Akakabe, Yoshihiko. Yamaguchi University; Japón Fil: Adachi, Osao. Yamaguchi University; Japón Fil: Hours, Roque Alberto. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Centro de Investigación y Desarrollo en Fermentaciones Industriales. Universidad Nacional de La Plata. Facultad de Ciencias Exactas. Centro de Investigación y Desarrollo en Fermentaciones Industriales; Argentina

An essential oil from dried "wakame" (Undaria pinnatifida), prepared by a simultaneous distillation extraction method, was analyzed by GC-MS, indicating the presence of one major component of volatiles. The volatile component was identified as (6Z,9Z,12Z,15Z,18Z)-1,6,9,12,15,18-henicosahexaene by comparison with the GC-MS and NMR spectra of synthetic. The henicosahexaene showed a subtly marine aroma. (6Z,9Z,12Z,15Z)-1,6,9,12,15-Henicosapentaene was also detected as a minor polyene in the essential oils. It was suggested that these polyenes contribute to the characteristic aroma of the dried wakame.

An essential oil from the brown alga Sargassum thunbergii, prepared by a simultaneous distillation extraction method, contained in two types of volatile polyenes with a terminal double bond such as (6Z,9Z,12Z,15Z,18Z)-1,6,9,12,15,18-henicosahexaene and (6Z,9Z,12Z,15Z)-1,6,9,12,15-henicosapentaene and with their saturated terminal structures such as (3Z,6Z,9Z,12Z,15Z,18Z)-3,6,9,12,15,18-henicosahexaene and (3Z,6Z,9Z,12Z,15Z)-3,6,9,12,15-henicosapentaene. These volatile polyenes were identified by comparison with the GC-MS and NMR spectra of synthetics. The polyenes with the saturated terminal structures were found in the brown algae for the first time.

Chlorogenic acid (CGA) and its hydrolysis products, quinic and caffeic acids are considered as fine chemicals and have a high commercial value. Yerba mate stems, useless residue from yerba mate processing, contains significant amounts of CGA. The goal of this study was to determine the best conditions for maximizing the CGA aqueous extraction from residues of yerba mate processing and to fit the extraction kinetics to empirical models. The effect of single factors such as solid-liquid ratio, numbers of extraction, temperature and time were studied for two particle sizes, using one factor at a time method and Response Surface Methodology (RSM). The highest and almost instantaneous CGA extraction (1.051 ± 0.015 gCGA L−1) was obtained using O particle size particle size >1 × 5 mm) the optimized conditions were 85 ± 5 °C and 25 ± 5 min, solid-liquid ratio of 1:20 and double stage extraction. For these last particles, the applied models of Pilosof et al. and Spiro and Jago showed a good agreement with the experimental and model calculated data. In the present study, it was possible to optimize the CGA extraction conditions for two particle sizes of yerba mate stems, in order to obtain extracts with high content of CGA that can be used in the production of others fine chemicals of interest in pharmaceutical industries.

Mitochondria, which evolved from a free-living bacterial ancestor, contain their own genomes and genetic systems and are produced from preexisting mitochondria by binary division. The mitochondrion-dividing (MD) ring is the main skeletal structure of the mitochondrial division machinery. However, the assembly mechanism and molecular identity of the MD ring are unknown. Multi-omics analysis of isolated mitochondrial division machinery from the unicellular alga Cyanidioschyzon merolae revealed an uncharacterized glycosyltransferase, MITOCHONDRION-DIVIDING RING1 (MDR1), which is specifically expressed during mitochondrial division and forms a single ring at the mitochondrial division site. Nanoscale imaging using immunoelectron microscopy and componential analysis demonstrated that MDR1 is involved in MD ring formation and that the MD ring filaments are composed of glycosylated MDR1 and polymeric glucose nanofilaments. Down-regulation of MDR1 strongly interrupted mitochondrial division and obstructed MD ring assembly. Taken together, our results suggest that MDR1 mediates the synthesis of polyglucan nanofilaments that assemble to form the MD ring. Given that a homolog of MDR1 performs similar functions in chloroplast division, the establishment of MDR1 family proteins appears to have been a singular, crucial event for the emergence of endosymbiotic organelles.

A novel oxidation of D-pentonates to 4-keto-D-pentonates was analyzed with Gluconobacter Thailandicus NBRC 3258. D-Pentonate 4-dehydrogenase activity in the membrane fraction was readily inactivated by EDTA and it was reactivated by the addition of PQQ and Ca2+. D-Pentonate 4-dehydrogenase was purified to two different subunits, 80 and 14 kDa. The absorption spectrum of the purified enzyme showed no typical absorbance over the visible regions. The enzyme oxidized D-pentonates to 4-keto-D-pentonates at the optimum pH of 4.0. In addition, the enzyme oxidized D-fructose to 5-keto-D-fructose, D-psicose to 5-keto-D-psicose, including the other polyols such as, glycerol, D-ribitol, D-arabitol, and D-sorbitol. Thus, D-pentonate 4-dehydrogenase was found to be identical with glycerol dehydrogenase (GLDH), a major polyol dehydrogenase in Gluconobacter species. The reaction versatility of quinoprotein GLDH was notified in this study., Facultad de Ciencias Exactas, Centro de Investigación y Desarrollo en Fermentaciones Industriales

An essential oil from the brown alga Sargassum thunbergii, prepared by a simultaneous distillation extraction method, contained in two types of volatile polyenes with a terminal double bond such as (6Z,9Z,12Z,15Z,18Z)-1,6,9,12,15,18-henicosahexaene and (6Z,9Z,12Z,15Z)-1,6,9,12,15-henicosapentaene and with their saturated terminal structures such as (3Z,6Z,9Z,12Z,15Z,18Z)-3,6,9,12,15,18-henicosahexaene and (3Z,6Z,9Z,12Z,15Z)-3,6,9,12,15-henicosapentaene. These volatile polyenes were identified by comparison with the GC-MS and NMR spectra of synthetics. The polyenes with the saturated terminal structures were found in the brown algae for the first time.

An essential oil from dried "wakame" (Undaria pinnatifida), prepared by a simultaneous distillation extraction method, was analyzed by GC-MS, indicating the presence of one major component of volatiles. The volatile component was identified as (6Z,9Z,12Z,15Z,18Z)-1,6,9,12,15,18-henicosahexaene by comparison with the GC-MS and NMR spectra of synthetic. The henicosahexaene showed a subtly marine aroma. (6Z,9Z,12Z,15Z)-1,6,9,12,15-Henicosapentaene was also detected as a minor polyene in the essential oils. It was suggested that these polyenes contribute to the characteristic aroma of the dried wakame.

Membrane-bound, pyrroloquinoline quinone (PQQ)-dependent glycerol dehydrogenase (GLDH, or polyol dehydrogenase) of Gluconobacter sp. oxidizes various secondary alcohols to produce the corresponding ketones, such as oxidation of D-sorbitol to L-sorbose in vitamin C production. Substrate specificity of GLDH is considered limited to secondary alcohols in the D-erythro configuration at the next to the last carbon. Here, we suggest that L-ribose, D- and L-lyxoses, and L-tagatose are also substrates of GLDH, but these sugars do not meet the substrate specificity rule of GLDH. The oxygen consumption activity of wild-type Gluconobacter frateurii cell membranes depends on several kinds of sugars as compared with that of the membranes of a GLDH-negative variant. Biotransformation of those sugars with the membranes was examined to determine the reaction products. A time course measuring the pH in the reaction mixture and the increase or decrease in substrates and products on TLC suggested that oxidation products of L-lyxose and L-tagatose were ketones with unknown structures, but those of L-ribose and D-lyxose were acids. The oxidation product of L-ribose was purified and revealed to be L-ribonate by HRMS and NMR analysis. Biotransformation of L-ribose with the membranes and also with the whole cells produced L-ribonate in nearly stoichiometric amounts, indicating that the specific oxidation site in L-ribose is recognized by GLDH. Since purified GLDH produced L-ribonate without any intermediate-like compounds, we propose here a reaction model where the first carbon in the pyranose form of L-ribose is oxidized by GLDH to L-ribonolactone, which is further hydrolyzed spontaneously to produce L-ribonate.