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Frontiers in Microbiology 2024Lanzhou lily ( var. ) is an exclusive sweet lily variety indigenous to China, which is susceptible to bulbous rot caused by fungal infection during storage. This...
Lanzhou lily ( var. ) is an exclusive sweet lily variety indigenous to China, which is susceptible to bulbous rot caused by fungal infection during storage. This experiment tests the pathogenicity of the pure culture isolated from the diseased tissue was confirmed in accordance with Koch's postulates, and the pathomycetes were identified based on their morphological and molecular characteristics. Furthermore, the biological characteristics of the pathogens were investigated, followed by an evaluation of the antifungal effects of three plant essential oils against them. The results showed that two strains of fungi were isolated from Lanzhou lily rot, which were identified as Schl. and (Bain. Et sart.). In addition, the pathogenicity of these two strains of fungi was demonstrated that only induced rot with similar symptoms during the post-harvest storage period. The biological characteristics of indicated the potato maltose agar and lily dextrose agar were identified as the most suitable media. Sucrose was determined to be the optimal carbon source, while ammonium nitrate was found to be the best nitrogen source for the growth of . Mycelial growth and sporulation of occurred at an optimum pH value of 6. Total darkness facilitated mycelial growth and conidial germination. The ideal temperature for growth was found to be 28°C, while relative humidity did not significantly impact mycelial growth; however, a relative humidity of 55% was most favorable for spore production. Among the three essential oils tested, cinnamon essential oil displayed superior antifungal efficacy against , whereas angelica essential oil and tea tree essential oil also exhibited moderate inhibitory effects against this pathogen. This research provides valuable theoretical insights for disease control during the storage and transportation of Lanzhou lily.
PubMed: 38666262
DOI: 10.3389/fmicb.2024.1307966 -
Bioresources and Bioprocessing Jan 2024The bioconversion of 4-hydroxy-2-keto acid derivatives via aldol condensation of formaldehyde and pyruvate has received substantial attention as potential source of...
The bioconversion of 4-hydroxy-2-keto acid derivatives via aldol condensation of formaldehyde and pyruvate has received substantial attention as potential source of chemicals for production of amino acids, hydroxy carboxylic acids, and chiral aldehydes. We developed an environmentally friendly biocatalyst consisting of a novel thermostable class II pyruvate aldolase from Deinococcus radiodurans with maltose-binding protein (MBP-DrADL), which has specific activity of 46.3 µmol min mg. Surprisingly, MBP-DrADL maintained over 60% of enzyme activity for 4 days at 50 to 65 °C, we used MBP-DrADL as the best candidate enzyme to produce 2-keto-4-hydroxybutyrate (2-KHB) from formaldehyde and pyruvate via aldol condensation. The optimum reaction conditions for 2-KHB production were 50 °C, pH 8.0, 5 mM Mg, 100 mM formaldehyde, and 200 mM pyruvate. Under these optimized conditions, MBP-DrADL produced 76.5 mM (8.94 g L) 2-KHB over 60 min with a volumetric productivity of 8.94 g L h and a specific productivity of 357.6 mg mg-enzyme h. Furthermore, 2-KHB production was improved by continuous addition of substrates, which produced approximately 124.8 mM (14.6 g L) of 2-KHB over 60 min with a volumetric productivity and specific productivity of 14.6 g L h and 583.4 mg mg-enzyme h, respectively. MBP-DrADL showed the highest specific productivity for 2-KHB production yet reported. Our study provides a highly efficient biocatalyst for the synthesis of 2-KHB and lays the foundation for large-scale production and application of high-value compounds from formaldehyde.
PubMed: 38647973
DOI: 10.1186/s40643-024-00727-x -
Bioresources and Bioprocessing Sep 2023Trehalose is a functional sugar that has numerous applications in food, cosmetic, and pharmaceutical products. Production of trehalose from maltose via a single-step...
Trehalose is a functional sugar that has numerous applications in food, cosmetic, and pharmaceutical products. Production of trehalose from maltose via a single-step enzymatic catalysis using trehalose synthase (TreS) is a promising method compared with the conventional two-step process due to its simplicity with lower formation of byproducts. In this study, a cold-active trehalose synthase (PaTreS) from Pseudarthrobacter sp. TBRC 2005 was heterologously expressed and characterized. PaTreS showed the maximum activity at 20 °C and maintained 87% and 59% of its activity at 10 °C and 4 °C, respectively. The enzyme had remarkable stability over a board pH range of 7.0-9.0 with the highest activity at pH 7.0. The activity was enhanced by divalent metal ions (Mg, Mn and Ca). Conversion of high-concentration maltose syrup (100-300 g/L) using PaTreS yielded 71.7-225.5 g/L trehalose, with 4.5-16.4 g/L glucose as a byproduct within 16 h. The work demonstrated the potential of PaTreS as a promising biocatalyst for the development of low-temperature trehalose production, with the advantages of reduced risk of microbial contamination with low generation of byproduct.
PubMed: 38647947
DOI: 10.1186/s40643-023-00681-0 -
Molecular Metabolism Jun 2024Hepatic glucose metabolism is profoundly perturbed by excessive alcohol intake. miR-141/200c expression is significantly induced by chronic ethanol feeding. This study...
OBJECTIVE
Hepatic glucose metabolism is profoundly perturbed by excessive alcohol intake. miR-141/200c expression is significantly induced by chronic ethanol feeding. This study aimed at identifying the role of miR-141/200c in glucose homeostasis during chronic ethanol exposure.
METHODS
WT and miR-141/200c KO mice were fed a control or an ethanol diet for 30 days, followed by a single binge of maltose dextrin or ethanol, respectively. Untargeted metabolomics analysis of hepatic primary metabolites was performed along with analyses for liver histology, gene expression, intracellular signaling pathways, and physiological relevance. Primary hepatocytes were used for mechanistic studies.
RESULTS
miR-141/200c deficiency rewires hepatic glucose metabolism during chronic ethanol feeding, increasing the abundance of glucose intermediates including G6P, an allosteric activator for GS. miR-141/200c deficiency replenished glycogen depletion during chronic ethanol feeding accompanied by reduced GS phosphorylation in parallel with increased expression of PP1 glycogen targeting subunits. Moreover, miR-141/200c deficiency prevented ethanol-mediated increases in AMPK and CaMKK2 activity. Ethanol treatment reduced glycogen content in WT-hepatocytes, which was reversed by dorsomorphin, a selective AMPK inhibitor, while KO-hepatocytes displayed higher glycogen content than WT-hepatocytes in response to ethanol treatment. Furthermore, treatment of hepatocytes with A23187, a calcium ionophore activating CaMKK2, lowered glycogen content in WT-hepatocytes. Notably, the suppressive effect of A23187 on glycogen deposition was reversed by dorsomorphin, demonstrating that the glycogen depletion by A23187 is mediated by AMPK. KO-hepatocytes exhibited higher glycogen content than WT-hepatocytes in response to A23187. Finally, miR-141/200c deficiency led to improved glucose tolerance and insulin sensitivity during chronic ethanol feeding.
CONCLUSIONS
miR-141/200c deficiency replenishes ethanol-mediated hepatic glycogen depletion through the regulation of GS activity and calcium signaling coupled with the AMPK pathway, improving glucose homeostasis and insulin sensitivity. These results underscore miR-141/200c as a potential therapeutic target for the management of alcohol intoxication.
Topics: Animals; Ethanol; Mice; MicroRNAs; Hepatocytes; Liver; Mice, Knockout; Liver Glycogen; Male; Mice, Inbred C57BL; Glucose
PubMed: 38642890
DOI: 10.1016/j.molmet.2024.101942 -
International Journal of Biological... May 2024The subfamily GH13_16 trehalose synthase (TreS) converts maltose to trehalose and vice versa. Typically, it consists of three domains, but it may contain a C-terminal...
The subfamily GH13_16 trehalose synthase (TreS) converts maltose to trehalose and vice versa. Typically, it consists of three domains, but it may contain a C-terminal extension exhibiting clear sequence features of a maltokinase (MaK). The present in silico study was focused on collection of naturally fused TreS-MaKs and their subsequent detailed bioinformatics analysis. Hence a set of total 3354 unique sequences was compared consisting of 1900 single TreSs, 1426 fused TreS-MaKs and 28 single MaKs. Fused TreS-MaKs were divided into five groups, namely with a standard MaK, with mutations in the maltose-binding site, of the catalytic nucleophile, of the general acid/base and of both catalytic residues. Sequence logos bearing the best conserved sequence regions were prepared for both TreSs and MaKs in an effort to find unique sequence features. In addition, linkers connecting the TreS and MaK parts in the fused enzymes were analysed. This analysis revealed that MaKs in fused enzymes have an extended N-terminal regions compared to single MaKs. Finally, the evolutionary relationships were demonstrated by phylogenetic trees of TreS parts from single TreSs and fused TreS-MaKs from the same organism as well as of single TreSs existing in multiple isoforms in the same organism.
Topics: Glucosyltransferases; Phylogeny; Glucans; Protein Domains; Amino Acid Sequence
PubMed: 38641282
DOI: 10.1016/j.ijbiomac.2024.131680 -
Food Chemistry Aug 2024Street foods are often of poor nutritional quality with high sugar content, in which the overconsumption of sugar is associated with obesity. However, sugar content...
Street foods are often of poor nutritional quality with high sugar content, in which the overconsumption of sugar is associated with obesity. However, sugar content information on local street foods is scarce. Thus, the individual and total sugar contents of 94 types of street foods in Malaysia were analysed. Compared to snacks and main meals, desserts contained the highest amounts of sugar, sucrose, fructose, glucose, and maltose. Sucrose was predominant in 90% desserts, 79.3% snacks, and 68.6% main meals. Most desserts (93.3%) contained medium to high sugar content (≥5 g to >15 g/100 g), while 82.9% main meals and 65.5% snacks had low sugar content. When comparing the sugar contents of 39 foods with other local databases, 58.3% main meals, 55.6% desserts, and 33.3% snacks contained either significantly (p < 0.05) higher or lower sugar contents. Consumers can identify low and high-sugar foods, and policymakers can review health priorities to combat obesity.
Topics: Malaysia; Humans; Snacks; Sugars; Nutritive Value; Food Analysis; Obesity; Dietary Sugars
PubMed: 38631211
DOI: 10.1016/j.foodchem.2024.139288 -
Plants (Basel, Switzerland) Mar 2024and are wild edible Mediterranean plants used in the human diet. This study presents the initial findings on the phytochemical characterization of Tunisian and...
and are wild edible Mediterranean plants used in the human diet. This study presents the initial findings on the phytochemical characterization of Tunisian and organs. It examined their mineral, sugar, organic acid, polyphenolic, and seed storage protein contents, as well as their antioxidant potential. In , stems had high sodium and potassium contents, while the immature and mature seeds were rich in calcium and magnesium. However, had high potassium levels in stems and high sodium and calcium levels in the flowers. showed substantial fructose variation among its organs. Conversely, exhibited significant heterogeneity in glucose, sucrose, and maltose levels across its organs, with maltose exclusively detected in the immature seeds. A notable organ-dependent distribution of organic acids was observed among the two species. Higher levels of phenolic contents were detected in both mature and immature seeds in both species compared to the other plant parts. The seeds possessed higher antioxidant activities than other plant organs. In both and seeds, albumins and globulins were the predominant protein fractions. This study brings evidence supporting the important potential of organs as sources of nutrients with antioxidant properties for producing functional food.
PubMed: 38611518
DOI: 10.3390/plants13070989 -
Foods (Basel, Switzerland) Mar 2024In this study, the effect of different heating temperatures (80, 90, 100, and 121 °C) on the physicochemical and volatile flavor properties of fried mantles...
In this study, the effect of different heating temperatures (80, 90, 100, and 121 °C) on the physicochemical and volatile flavor properties of fried mantles (Argentinian shortfin) was investigated. The squid mantles were soaked in a maltose syrup solution (20% /) for 10 s and fried in soybean oil for 10 s (160 °C), vacuum-packed, and processed at different temperatures for 10 min. Then, the squid mantles were subjected to colorimetric analysis, sensory evaluation, free amino acid analysis, and texture profile analysis. In addition, the volatile organic compounds (VOCs) in the squid mantles were analyzed. The results revealed that lower treating temperatures (80 and 90 °C) improved the chromatic and textural properties, along with organoleptic perception. Additionally, the content of amino acid in the squid mantles treated at 121 °C was significantly lower than that of the samples treated at other temperatures ( < 0.05). Headspace-gas chromatography-ion mobility spectrometry (HS-GC-IMS) was used to detect 41 VOCs, including their monomers and dimers. Among these detected VOCs, the contents of alcohols, ketones, and pyrazines were positively correlated with temperature. However, the content of aldehydes in the squid mantles gradually decreased as the heating temperature increased ( < 0.05). The combined HS-GC-IMS and E-nose results revealed that the lower temperatures (80 and 90 °C) were more suitable for flavor development and practical processing. This study provides valuable information for properly controlling the heating process of squid products, as well as flavor and practical applications for the aquatic industry.
PubMed: 38611331
DOI: 10.3390/foods13071025 -
Chemical Reviews Apr 2024Bacteria have acquired sophisticated mechanisms for assembling and disassembling polysaccharides of different chemistry. α-d-Glucose homopolysaccharides, so-called... (Review)
Review
Bacteria have acquired sophisticated mechanisms for assembling and disassembling polysaccharides of different chemistry. α-d-Glucose homopolysaccharides, so-called α-glucans, are the most widespread polymers in nature being key components of microorganisms. Glycogen functions as an intracellular energy storage while some bacteria also produce extracellular assorted α-glucans. The classical bacterial glycogen metabolic pathway comprises the action of ADP-glucose pyrophosphorylase and glycogen synthase, whereas extracellular α-glucans are mostly related to peripheral enzymes dependent on sucrose. An alternative pathway of glycogen biosynthesis, operating via a maltose 1-phosphate polymerizing enzyme, displays an essential wiring with the trehalose metabolism to interconvert disaccharides into polysaccharides. Furthermore, some bacteria show a connection of intracellular glycogen metabolism with the genesis of extracellular capsular α-glucans, revealing a relationship between the storage and structural function of these compounds. Altogether, the current picture shows that bacteria have evolved an intricate α-glucan metabolism that ultimately relies on the evolution of a specific enzymatic machinery. The structural landscape of these enzymes exposes a limited number of core catalytic folds handling many different chemical reactions. In this Review, we present a rationale to explain how the chemical diversity of α-glucans emerged from these systems, highlighting the underlying structural evolution of the enzymes driving α-glucan bacterial metabolism.
Topics: Glucans; Bacteria; Evolution, Molecular
PubMed: 38606812
DOI: 10.1021/acs.chemrev.3c00811 -
American Journal of Veterinary Research Jun 2024To investigate associations between hepatic fat accumulation, fibrosis, and plasma values of primary metabolites, biochemical measurands, insulin, and lipoproteins in...
Hepatic lipid accumulation is associated with multiple metabolic pathway alterations but not dyslipidemia and insulin resistance in central bearded dragons (Pogona vitticeps).
OBJECTIVE
To investigate associations between hepatic fat accumulation, fibrosis, and plasma values of primary metabolites, biochemical measurands, insulin, and lipoproteins in bearded dragons.
ANIMALS
48 adult central bearded dragons (Pogona vitticeps).
METHODS
Dragons were sedated with alfaxalone, and a blood sample was collected. Plasma was submitted for untargeted primary metabolomics using gas chromatography time-of-flight mass spectrometry, a biochemistry panel, and a lipoprotein panel determined by PAGE. Hepatic lipid content was quantified by liver attenuation measurements from CT images and digital image analysis of standardized histologic sections of the liver. Fibrosis was quantified by digital image analysis on Masson's trichrome-stained histologic sections. Severity was determined from pathologic review of liver sections according to a standardized grading system. Statistical associations were investigated using serial linear models adjusted for false discovery rate and multivariate statistics.
RESULTS
Both hepatic fat and fibrosis had a significant effect on CT liver attenuation values. Several oligosaccharides (maltotriose, maltose, ribose, trehalose) and alkaline phosphatase were significantly and linearly increased with hepatic lipid content (all q < .05). On partial least square-discriminant analysis, β-hydroxybutyric acid was the most important discriminatory variable between fatty liver severity grades on histology. No significant associations were found with insulin, lipoproteins, and succinic acid.
CLINICAL RELEVANCE
Bearded dragons with hepatic lipid accumulation experienced multiple metabolic pathway disruptions, some being compatible with mitochondrial dysfunction. No evidence of insulin resistance or dyslipidemia was found. Hepatic biopsy and histopathology remain recommended for reliably diagnosing and staging fatty liver disease in bearded dragons.
Topics: Animals; Insulin Resistance; Male; Liver; Female; Dyslipidemias; Lizards; Lipid Metabolism; Fatty Liver
PubMed: 38593838
DOI: 10.2460/ajvr.23.12.0285