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EFSA Journal. European Food Safety... Mar 2024The food enzyme mucorpepsin (EC 3.4.23.23) is produced with the non-genetically modified strain LP-N836 by Meito Sangyo Co., Ltd. The native enzyme can be chemically...
The food enzyme mucorpepsin (EC 3.4.23.23) is produced with the non-genetically modified strain LP-N836 by Meito Sangyo Co., Ltd. The native enzyme can be chemically modified to produce a more thermolabile form. The food enzyme is free from viable cells of the production organism. It is intended to be used in the processing of dairy products for the production of cheese and fermented dairy products. Dietary exposure to the food enzyme-total organic solids (TOS) was estimated to be up to 0.108 mg TOS/kg body weight (bw) per day in European populations. Genotoxicity tests did not indicate a safety concern. The systemic toxicity was assessed by means of a repeated dose 90-day oral toxicity study in rats. The Panel identified a no observed adverse effect level of 95 mg TOS/kg bw per day, the mid-dose tested, which when compared with the estimated dietary exposure, resulted in a margin of exposure of at least 880. A search for the similarity of the amino acid sequence of the food enzyme to known allergens was made and four matches with respiratory allergens and one with a food allergen (mustard) were found. The Panel considered that the risk of allergic reactions upon dietary exposure to this food enzyme, particularly in individuals sensitised to mustard proteins, cannot be excluded. Based on the data provided, the Panel concluded that both the native and thermolabile forms of this food enzyme do not give rise to safety concerns under the intended conditions of use.
PubMed: 38450083
DOI: 10.2903/j.efsa.2024.8631 -
EFSA Journal. European Food Safety... Feb 2024The food enzyme mucorpepsin (EC 3.4.23.23) is produced with the non-genetically modified strain M19-21 by Meito Sangyo Co., Ltd. The enzyme is chemically modified to...
The food enzyme mucorpepsin (EC 3.4.23.23) is produced with the non-genetically modified strain M19-21 by Meito Sangyo Co., Ltd. The enzyme is chemically modified to produce a thermolabile form. The food enzyme was considered free from viable cells of the production organism. It is intended to be used in the processing of dairy products for the production of cheese and fermented dairy products. Based on the maximum use levels, dietary exposure was estimated to be up to 0.108 mg TOS/kg body weight (bw) per day in European populations. Genotoxicity tests did not indicate a safety concern. The systemic toxicity was assessed by means of a repeated dose 90-day oral toxicity study in rats. The Panel identified a no observed adverse effect level of 226 mg TOS/kg bw per day, the highest dose tested, which, when compared with the estimated dietary exposure, results in a margin of exposure of at least 2093. A search for the similarity of the amino acid sequence of the food enzyme to known allergens was made and four matches to respiratory allergens and one match to a food allergen (mustard) were found. The Panel considered that the risk of allergic reactions upon dietary exposure to this food enzyme, particularly in individuals sensitised to mustard proteins, cannot be excluded. Based on the data provided, the Panel concluded that this food enzyme does not give rise to safety concerns, under the intended conditions of use.
PubMed: 38410150
DOI: 10.2903/j.efsa.2024.8633 -
Frontiers in Microbiology 2024This study investigated the microbial community in three-color sauce-flavor (black, yellow, and white) throughout their maturation processes, together with their...
This study investigated the microbial community in three-color sauce-flavor (black, yellow, and white) throughout their maturation processes, together with their physicochemical factors, culturable microbes, flavor components, and fermenting vitalities. Results from high-throughput sequencing revealed distinct microbial diversity, with more pronounced variations in bacterial community than in fungal community. Firmicutes and Ascomycota emerged as the most dominant bacterial and fungal phyla, respectively, during maturation. Genus-level analysis identified , , and as dominant bacteria in black , yellow , and white , severally, while was shared as the core dominant fungi for these . Physicochemical factors, particularly acidity, were found to exert a significant impact on microbial community. was the key bacteria influencing the color formation of these . Furthermore, correlations between dominant microbes and flavor compounds highlighted their role in quality. Molds (, , and ), excepting , played a crucial role in the formation of pyrazine compounds. Consequently, this study offers innovative insights into the microbial perspectives on color and pyrazine formation, establishing a groundwork for future mechanized production and quality control of sauce-flavor baijiu.
PubMed: 38328433
DOI: 10.3389/fmicb.2024.1345772 -
Frontiers in Microbiology 2024Proso millet, a high-quality fermentation material used for Chinese yellow wine production, can produce special flavored substances; however, its role in improving the...
INTRODUCTION
Proso millet, a high-quality fermentation material used for Chinese yellow wine production, can produce special flavored substances; however, its role in improving the flavor and altering microbial communities of light-flavored Baijiu during fermentation remain unknown. Thus, we aimed to investigate the effect of proso millet on improving the flavor of light-flavored Baijiu and altering microbial communities during different fermentation stages.
METHODS
The dynamic changes in the microbial communities and flavor of proso millet (50%) + sorghum (50%) mixed fermentation samples were analyzed through intermittent sampling on days 7, 14, 21, and 28 of the fermentation process. Microbial high-throughput sequencing and the analysis of flavor characteristics were conducted through 16S DNA/ ITS amplicon sequencing and gas chromatography (multi-capillary column)-ion mobility spectrometry, respectively.
RESULTS
Proso millet significantly changed the core flavor compound composition of traditional light-flavored Baijiu from ethyl acetate, ethyl hexanoate, ethyl hexanoate dimer, ethyl butanoate, ethyl lactate, and butyl acetate to oct-2-ene, 2-butanol, propyl propanoate, 2-pentenal, and 4-methylpentanal. The amplicon sequencing analysis revealed that the alpha diversity parameters of bacterial and fungal communities, including the Chao1, Pielou_e, Shannon, and Simpson indices, for proso millet-sorghum mixed fermentation samples were significantly higher than those for sorghum fermentation samples ( < 0.05). Of the 40 most significant microbial genera in two treatments, proso millet significantly increased the abundance of 12 bacterial and 18 fungal genera. Among the 40 most significant bacterial and fungal species, 23 bacterial species belonged to the genus, whereas the 30 primary fungal species belonged to 28 different genera. The analysis of the relationship between microbial changes and the main flavor compounds of light-flavored Baijiu showed that bacteria from the , , , , , , , , , , , genera and fungi from the , , , , , , and genera significantly inhibited the synthesis of ethyl hexanoate, ethyl butanoate, ethyl lactate ethyl lactate, and butyl acetate but increased the synthesis of ethyl acetate ( < 0.05). Moreover, these microbes exhibited a significantly greater abundance in proso millet-sorghum mixed fermentation samples than in sorghum samples. The synthesis of special flavored compounds in proso millet Baijiu was significantly positively correlated with the presence of fungi from the , , , , and genera but negative correlated with the presence of bacteria from the , , , , , and genera. Regarding ethanol content, the low alcohol content of Fenjiu may be due to the significantly high abundance of fungi from the genus and bacteria from the , , , and genera during fermentation. In summary, proso millet significantly altered the flavor of light-flavored Baijiu by inducing the formation of a special microbial community; however, it did not increase alcohol concentration.
DISCUSSION
This study lays the foundation for future research on Baijiu fermentation. Additionally, the study findings may help improve the production efficiency and elevate the quality and flavor of the final product.
PubMed: 38318340
DOI: 10.3389/fmicb.2024.1333466 -
Open Forum Infectious Diseases Jan 2024Mucormycosis is a potentially lethal mycosis. We reviewed peer-reviewed publications on mucormycosis to assess therapeutic outcomes. (Review)
Review
BACKGROUND
Mucormycosis is a potentially lethal mycosis. We reviewed peer-reviewed publications on mucormycosis to assess therapeutic outcomes.
METHODS
A systematic literature search using the Ovid MEDLINE and EMBASE databases identified manuscripts describing human mucormycosis diagnosed according to European Organization for Research and Treatment of Cancer and the Mycoses Study Group criteria with therapeutic outcomes published from 2000 to 2022.
RESULTS
In 126 articles, 10 335 patients were described, most from Asia (n = 6632, 66%). Diabetes was the most frequent underlying disease (n = 6188, 60%); 222 (2.1%) patients had no underlying diseases. The dominant clinical form was rhino-orbitocerebral (n = 7159, 69.3%), followed by pulmonary (n = 1062, 10.3%). Of 5364 patients with outcome data, amphotericin B monotherapy (n = 3749, mortality 31.5%) was most frequent, followed by amphotericin B + azole (n = 843, mortality 6.6%; < .0001), amphotericin B followed by azole (n = 357, mortality 13.7%; < .0001), posaconazole only (n = 250, mortality 17.2%; < .0001), and isavuconazole only (n = 65, mortality 24.6%; = .24). Duration and dose of antifungals varied widely. Documented outcomes from surgical resections in 149 patients found that 47 of 125 died (37.6%), compared with 16 of 24 (66.7%) patients who did not undergo surgery ( = .008).
CONCLUSIONS
Mucormycosis is more frequently reported in Asia than in Europe and is often linked to diabetes. Antifungal therapy, usually with surgery, is frequently effective for mucormycosis.
PubMed: 38288347
DOI: 10.1093/ofid/ofad704 -
International Journal of Biological... Mar 2024The incorporation of a non-specific lipase and a sn-1,3 specific one in a single immobilized system can be a promising approach for the exploitation of both lipases. A...
The incorporation of a non-specific lipase and a sn-1,3 specific one in a single immobilized system can be a promising approach for the exploitation of both lipases. A one-step immobilization platform mediated by an isocyanide-based multi-component reaction was applied to create co-cross-linked enzymes (co-CLEs) of lipases from Rhizomucor miehei (sn-1,3 specific) and Candida antarctica (non-specific). Glutaraldehyde was found to be effective cross-linker by producing specific activity of 16.9 U/mg and immobilization yield of 99 %. High activity recovery of up to 404 % was obtained for immobilized derivatives. Leaking experiment showed covalent nature of the cross-linking processes. BSA had considerable effect on the immobilization process, providing 87-100 % immobilization yields and up to 10 times improvement in the specific activity of the immobilized derivatives. Scanning electron microscopy images showed flower-like and rod-like structures for the CLEs prepared by glutaraldehyde and undecanedicarboxylic acid, respectively. The prepared co-CLEs were examined in non-selective enrichment of eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) from fish oil, showing capability of releasing up to 100 % of both omega-3 fatty acids within 8 h of the reaction. The reusability of co-CLEs in five successive cycles presented retaining 63-72 % of their initial activities after the fifth reuse cycle in the hydrolysis reaction.
Topics: Fatty Acids, Omega-3; Fish Oils; Glutaral; Enzymes, Immobilized; Lipase; Rhizomucor; Fungal Proteins
PubMed: 38272408
DOI: 10.1016/j.ijbiomac.2024.129362 -
Glycobiology Apr 2024The marine environment, contains plentiful renewable resources, e.g. macroalgae with unique polysaccharides, motivating search for enzymes from marine microorganisms to...
The marine environment, contains plentiful renewable resources, e.g. macroalgae with unique polysaccharides, motivating search for enzymes from marine microorganisms to explore conversion possibilities of the polysaccharides. In this study, the first GH17 glucanosyltransglycosylase, MlGH17B, from a marine bacterium (Muricauda lutaonensis), was characterized. The enzyme was moderately thermostable with Tm at 64.4 °C and 73.2 °C, but an activity optimum at 20 °C, indicating temperature sensitive active site interactions. MlGH17B uses β-1,3 laminari-oligosaccharides with a degree of polymerization (DP) of 4 or higher as donors. Two glucose moieties (bound in the aglycone +1 and +2 subsites) are cleaved off from the reducing end of the donor while the remaining part (bound in the glycone subsites) is transferred to an incoming β-1,3 glucan acceptor, making a β-1,6-linkage, thereby synthesizing branched or kinked oligosaccharides. Synthesized oligosaccharides up to DP26 were detected by mass spectrometry analysis, showing that repeated transfer reactions occurred, resulting in several β-1,6-linked branches. The modeled structure revealed an active site comprising five subsites: three glycone (-3, -2 and -1) and two aglycone (+1 and +2) subsites, with significant conservation of substrate interactions compared to the only crystallized 1,3-β-glucanosyltransferase from GH17 (RmBgt17A from the compost thriving fungus Rhizomucor miehei), suggesting a common catalytic mechanism, despite different phylogenetic origin, growth environment, and natural substrate. Both enzymes lacked the subdomain extending the aglycone subsites, found in GH17 endo-β-glucanases from plants, but this extension was also missing in bacterial endoglucanases (modeled here), showing that this feature does not distinguish transglycosylation from hydrolysis, but may rather relate to phylogeny.
Topics: Phylogeny; Oligosaccharides; Flavobacteriaceae; Polysaccharides; Substrate Specificity
PubMed: 38271624
DOI: 10.1093/glycob/cwae007 -
EFSA Journal. European Food Safety... Jan 2024The food enzyme mucorpepsin (EC 3.4.23.23) is produced with the non-genetically modified strain FRO by DSM Food Specialties B.V. The enzyme can be chemically modified...
The food enzyme mucorpepsin (EC 3.4.23.23) is produced with the non-genetically modified strain FRO by DSM Food Specialties B.V. The enzyme can be chemically modified to produce a thermolabile form. The food enzyme is free from viable cells of the production organism. It is intended to be used in three food manufacturing processes: processing of dairy products for the production of (1) cheese, (2) edible rennet casein, (3) fermented dairy products. Dietary exposure to the food enzyme-total organic solids (TOS) was estimated to be up to about 0.072 mg TOS/kg body weight (bw) per day in European populations. Genotoxicity tests did not indicate a safety concern. The systemic toxicity was assessed by means of a repeated dose 90-day oral toxicity study in rats. The Panel identified a no observed adverse effect level of 2000 mg TOS/kg bw per day, the highest dose tested, which, when compared with the estimated dietary exposure, results in a margin of exposure of at least 27,778. A search for the similarity of the amino acid sequence of the food enzyme to known allergens was made and five matches were found. The Panel considered that a risk of allergic reactions upon dietary exposure to this food enzyme cannot be excluded, but is considered low, except for individuals sensitised to mustard proteins, for whom the risk will not exceed that of mustard consumption. Based on the data provided, the Panel concluded that this food enzyme does not give rise to safety concerns under the intended conditions of use.
PubMed: 38250500
DOI: 10.2903/j.efsa.2024.8512 -
Journal of Microbiology and... Mar 2024To investigate the effect of the predominant fungal species from Korean traditional meju and doenjang on soybean fermentation, the enzymatic activity and amino acid...
To investigate the effect of the predominant fungal species from Korean traditional meju and doenjang on soybean fermentation, the enzymatic activity and amino acid production of twenty-two fungal strains were assessed through solid- and liquid-state soybean fermentation. Enzymatic activity analyses of solid-state fermented soybeans revealed different enzyme activities involving protease, leucine aminopeptidase (LAP), carboxypeptidase (CaP), glutaminase, γ-glutamyl transferase (GGT), and amylase, depending on the fungal species. These enzymatic activities significantly affected the amino acid profile throughout liquid-state fermentation. Strains belonging to , including , and , produced smaller amounts of total amino acids and umami-producing amino acids, such as glutamic acid and aspartic acid, than strains belonging to subgenus . The genera and produced large amounts of total amino acids and glutamic acid, suggesting that these genera play an essential role in producing umami and kokumi tastes in fermented soybean products. Strains belonging to subgenus , including , showed the highest amino acid content, including glutamic acid, suggesting the potential benefits of as a starter for soybean fermentation. This study showed the potential of traditional meju strains as starters for soybean fermentation. However, further analysis of processes such as the production of G-peptide for kokumi taste and volatile compounds for flavor and safety is needed.
Topics: Amino Acids; Soy Foods; Glycine max; Fermentation; Fungi; Aspergillus; Glutamic Acid; Peptide Hydrolases
PubMed: 38213301
DOI: 10.4014/jmb.2309.09008 -
Histopathology Mar 2024Mucormycosis is a fast-progressing disease with a high mortality rate. The most important factor determining survival of patients is early and accurate diagnosis....
AIMS
Mucormycosis is a fast-progressing disease with a high mortality rate. The most important factor determining survival of patients is early and accurate diagnosis. Although histopathology often recognises invasive mould infections at first, histomorphology alone is insufficient in providing an accurate diagnosis. Unbiased molecular methods to detect and identify fungi are promising, yet their role in complementing routine histopathological workflows has not been studied sufficiently.
METHODS AND RESULTS
We performed a retrospective single-centre study examining the clinical value of complementing histopathology with internal transcribed spacer (ITS) sequencing of fungal DNA in the routine diagnosis of mucormycosis. At our academic centre, we identified 14 consecutive mucormycosis cases diagnosed by histopathology and subsequent ITS sequencing. Using histomorphological examination, fungal hyphae could be detected in all cases; however, morphological features were unreliable regarding specifying the taxa. Subsequent ITS sequencing identified a remarkable phylogenetic diversity among Mucorales: the most common species was Rhizopus microsporus (six of 14; 42.9%), followed by Lichtheimia corymbifera (three of 14, 21.4%) and single detections of Rhizopus oryzae, Actinomucor elegans, Mucor circinelloides, Rhizomucor pusillus and Rhizomucor miehei (one of 14; 7.1%, respectively). In one case, we additionally detected Pneumocystis jirovecii in the same lung tissue specimen, suggesting a clinically relevant co-infection. Fungal culture was performed in 10 cases but yielded positive results in only two of 10 (20%), revealing its limited value in the diagnosis of mucormycosis.
CONCLUSIONS
Our study demonstrates that a combination of histopathology and ITS sequencing is a practically feasible approach that outperforms fungal culture in detecting Mucorales in tissue-associated infections. Therefore, pathologists might adapt diagnostic workflows accordingly when mucormycosis is suspected.
Topics: Humans; Mucormycosis; Retrospective Studies; Phylogeny
PubMed: 38192085
DOI: 10.1111/his.15131