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Journal of Oleo Science 2024The objectives were to optimize the reaction conditions for C10:0 incorporation into grapeseed (GS) oil, characterize the structured lipid (SL) product, and study the...
The objectives were to optimize the reaction conditions for C10:0 incorporation into grapeseed (GS) oil, characterize the structured lipid (SL) product, and study the changes in antioxidant activity of the SL. Taguchi method was used to optimize C10:0 incorporation by combining parameters in a total of 9 experiments. Lipozyme RM IM (Rhizomucor miehei immobilized lipase) and Lipozyme 435 (Candida antarctica recombinant immobilized lipase) were used as biocatalysts for the acidolysis reactions. C10:0 incorporation and triacylglycerol (TAG) species of the SL were analyzed to determine optimal conditions and enzyme type that gave higher incorporation. The optimal conditions were the same for both enzymes as follows: substrate molar ratio 1:3 (GS oil: C10:0), enzyme load 5% (w/w) of substrates, temperature 65℃, and time 12 h. HPLC analysis of SL gave MLM-type TAG species of 11.51±0.11 mol% and 12.68±0.34 mol% for Lipozyme RM IM and Lipozyme 435, respectively. GC analysis indicated that C10:0 incorporated at the sn-1,3 positions of the SL were 46.03±0.55 mol% and 47.28±1.22 mol%, respectively, for Lipozyme RM IM and Lipozyme 435. However, the total C10:0 incorporated into TAG species with Lipozyme RM IM was significantly higher (60.08±0.04 mol%) compared to 50.78±0.44 mol% for Lipozyme 435. Scaled-up (300 g) acidolysis reaction and characterization were done on SL synthesized using Lipozyme RM IM. SL reaction product was purified using short path distillation and fully characterized in terms of lipid classes, tocopherol, thermal behavior, and oxidative stability. The yield of purified scaled-up SL after short path distillation (SPD) was 72.96 wt%. The antioxidant in SL was reduced after SPD due to loss of tocopherols. This MLM-type-SL synthesized within 12 h using Lipozyme RM IM had a high content of C10:0 and may have functional and health benefits.
Topics: Lipase; Enzymes, Immobilized; Rhizomucor; Antioxidants; Decanoic Acids; Triglycerides; Plant Oils; Biocatalysis; Temperature; Time Factors; Basidiomycota
PubMed: 38945926
DOI: 10.5650/jos.ess23212 -
Frontiers in Cellular and Infection... 2024Mucormycosis is an uncommon invasive fungal infection that has a high mortality rate in patients with severe underlying diseases, which leads to immunosuppression. Due...
BACKGROUND
Mucormycosis is an uncommon invasive fungal infection that has a high mortality rate in patients with severe underlying diseases, which leads to immunosuppression. Due to its rarity, determining the incidence and optimal treatment methods for mucormycosis in children is challenging. Metagenomic next-generation sequencing (mNGS) is a rapid, precise and sensitive method for pathogen detection, which helps in the early diagnosis and intervention of mucormycosis in children. In order to increase pediatricians' understanding of this disease, we conducted a study on the clinical features of mucormycosis in children and assessed the role of mNGS in its diagnosis.
METHODS
We retrospectively summarized the clinical data of 14 children with mucormycosis treated at the First Affiliated Hospital of Zhengzhou University from January 2020 to September 2023.
RESULTS
Of the 14 cases, 11 case of mucormycosis were classified as probable, and 3 cases were proven as mucormycosis. Most children (85.71%) had high-risk factors for mucormycosis. All 14 children had lung involvement, with 5 cases of extrapulmonary dissemination. Among the 14 cases, 4 cases underwent histopathological examination of mediastinum, lung tissue or kidney tissue, in which fungal pathogens were identified in 3 patients. Fungal hyphae was identified in 3 cases of mucormycosis, but only 1 case yielded a positive culture result. All patients underwent mNGS testing with samples from blood (8/14), bronchoalveolar lavage fluid (6/14), and tissue (1/14). mNGS detected fungi in all cases: 7 cases had , 4 cases had , 3 cases had , 1 case had , and 1 case had . Coinfections were found with in 3 cases, bacteria in 3 cases, and viruses in 5 cases.
CONCLUSION
Children with mucormycosis commonly exhibit non-specific symptoms like fever and cough during the initial stages. Early diagnosis based on clinical symptoms and imaging is crucial in children suspected of having mucormycosis. mNGS, as a supplementary diagnostic method, offers greater sensitivity and shorter detection time compared to traditional mucormycosis culture or histopathological testing. Additionally, mNGS enables simultaneous detection of bacteria and viruses, facilitating timely and appropriate administration of antibiotics and thereby enhancing patient outcomes.
Topics: Humans; Mucormycosis; High-Throughput Nucleotide Sequencing; Male; Female; Child; Child, Preschool; Metagenomics; Retrospective Studies; Infant; Adolescent; Invasive Fungal Infections; China
PubMed: 38915923
DOI: 10.3389/fcimb.2024.1368165 -
Frontiers in Cellular and Infection... 2024Invasive mold diseases of the central nervous (CNS IMD) system are exceedingly rare disorders, characterized by nonspecific clinical symptoms. This results in...
BACKGROUND
Invasive mold diseases of the central nervous (CNS IMD) system are exceedingly rare disorders, characterized by nonspecific clinical symptoms. This results in significant diagnostic challenges, often leading to delayed diagnosis and the risk of misdiagnosis for patients. Metagenomic Next-Generation Sequencing (mNGS) holds significant importance for the diagnosis of infectious diseases, especially in the rapid and accurate identification of rare and difficult-to-culture pathogens. Therefore, this study aims to explore the clinical characteristics of invasive mold disease of CNS IMD in children and assess the effectiveness of mNGS technology in diagnosing CNS IMD.
METHODS
Three pediatric patients diagnosed with Invasive mold disease brain abscess and treated in the Pediatric Intensive Care Unit (PICU) of the First Affiliated Hospital of Zhengzhou University from January 2020 to December 2023 were selected for this study.
RESULTS
Case 1, a 6-year-old girl, was admitted to the hospital with "acute liver failure." During her hospital stay, she developed fever, irritability, and seizures. CSF mNGS testing resulted in a negative outcome. Multiple brain abscesses were drained, and was detected in pus culture and mNGS. The condition gradually improved after treatment with voriconazole combined with caspofungin. Case 2, a 3-year-old girl, was admitted with "acute B-lymphoblastic leukemia." During induction chemotherapy, she developed fever and seizures. was detected in the intracranial abscess fluid by mNGS, and the condition gradually improved after treatment with voriconazole combined with caspofungin, followed by "right-sided brain abscess drainage surgery." Case 3, a 7-year-old girl, showed lethargy, fever, and right-sided limb weakness during the pending chemotherapy period for acute B-lymphoblastic leukemia. and was detected in the cerebrospinal fluid by mNGS. The condition gradually improved after treatment with amphotericin B combined with posaconazole. After a six-month follow-up post-discharge, the three patients improved without residual neurological sequelae, and the primary diseases were in complete remission.
CONCLUSION
The clinical manifestations of CNS IMD lack specificity. Early mNGS can assist in identifying the pathogen, providing a basis for definitive diagnosis. Combined surgical treatment when necessary can help improve prognosis.
Topics: Humans; Female; High-Throughput Nucleotide Sequencing; Child; Metagenomics; Brain Abscess; Antifungal Agents; Invasive Fungal Infections; Male; Central Nervous System Fungal Infections; Child, Preschool; Aspergillus fumigatus; Caspofungin
PubMed: 38912204
DOI: 10.3389/fcimb.2024.1393242 -
Microbial Cell Factories May 2024Rhizomucor miehei (RM) lipase is a regioselective lipase widely used in food, pharmaceutical and biofuel industries. However, the high cost and low purity of the...
BACKGROUND
Rhizomucor miehei (RM) lipase is a regioselective lipase widely used in food, pharmaceutical and biofuel industries. However, the high cost and low purity of the commercial RM lipase limit its industrial applications. Therefore, it is necessary to develop cost-effective strategies for large-scale preparation of this lipase. The present study explored the high-level expression of RM lipase using superfolder green fluorescent protein (sfGFP)-mediated Escherichia coli secretion system.
RESULTS
The sfGFP mutant was fused to the C-terminus of RM lipase to mediate its secretion expression. The yield of the fusion protein reached approximately 5.1 g/L with high-density fermentation in 5-L fermentors. Unlike conventional secretion expression methods, only a small portion of the target protein was secreted into the cell culture while majority of the fusion protein was still remained in the cytoplasm. However, in contrast to intracellular expression, the target protein in the cytoplasm could be transported efficiently to the supernatant through a simple washing step with equal volume of phosphate saline (PBS), without causing cell disruption. Hence, the approach facilitated the downstream purification step of the recombinant RM lipase. Moreover, contamination or decline of the engineered strain and degradation or deactivation of the target enzyme can be detected efficiently because they exhibited bright green fluorescence. Next, the target protein was immobilized with anion-exchange and macropore resins. Diethylaminoethyl sepharose (DEAE), a weak-basic anion-exchange resin, exhibited the highest bind capacity but inhibited the activity of RM lipase dramatically. On the contrary, RM lipase fixed with macropore resin D101 demonstrated the highest specific activity. Although immobilization with D101 didn't improve the activity of the enzyme, the thermostability of the immobilized enzyme elevated significantly. The immobilized RM lipase retained approximately 90% of its activity after 3-h incubation at 80 °C. Therefore, D101 was chosen as the supporting material of the target protein.
CONCLUSION
The present study established a highly efficient strategy for large-scale preparation of RM lipase. This innovative technique not only provides high-purity RM lipase at a low cost but also has great potential as a platform for the preparation of lipases in the future.
Topics: Lipase; Rhizomucor; Escherichia coli; Enzymes, Immobilized; Green Fluorescent Proteins; Recombinant Fusion Proteins; Fermentation
PubMed: 38802857
DOI: 10.1186/s12934-024-02432-y -
Allergologie Select 2024None.
None.
PubMed: 38756207
DOI: 10.5414/ALX02444E -
Foods (Basel, Switzerland) Apr 2024Strong-flavor Daqu, as a fermentation agent, plays a significant role in shaping the quality of strong-flavor baijius, and fungal species in Daqu are important factors...
Strong-flavor Daqu, as a fermentation agent, plays a significant role in shaping the quality of strong-flavor baijius, and fungal species in Daqu are important factors affecting the quality of Daqu. Therefore, we selected strong-flavor Daqu from seven different origins to study the fungal composition and the effects of the fungal composition on the physicochemical properties and volatile organic compounds (VOCs). It was found that the fungal composition influences the physicochemical properties of Daqu. Specifically, there was a positive link between , , , and liquefying activity and a positive correlation between and fermenting activity. Furthermore, the relationships between esterifying activity and , , , , and were found to be positive. The VOCs in Daqu were affected by , , , and . was significantly positively correlated with benzeneethanol as well as and pentadecanoic acid ethyl ester, ethyl myristate. and were significantly negatively correlated with benzaldehyde and 2-furaldehyde. This study deepens our understanding of the relationship between VOCs, the physicochemical properties with microbial communities, and reference significance for the production of better-quality strong-flavor Daqu.
PubMed: 38672935
DOI: 10.3390/foods13081263 -
Regulatory Toxicology and Pharmacology... Jun 2024The world's hunger for novel food ingredients drives the development of safe, sustainable, and nutritious novel food products. For foods containing novel proteins,...
The world's hunger for novel food ingredients drives the development of safe, sustainable, and nutritious novel food products. For foods containing novel proteins, potential allergenicity of the proteins is a key safety consideration. One such product is a fungal biomass obtained from the fermentation of Rhizomucor pusillus. The annotated whole genome sequence of this strain was subjected to sequence homology searches against the AllergenOnline database (sliding 80-amino acid windows and full sequence searches). In a stepwise manner, proteins were designated as potentially allergenic and were further compared to proteins from commonly consumed foods and from humans. From the sliding 80-mer searches, 356 proteins met the conservative >35% Codex Alimentarius threshold, 72 of which shared ≥50% identity over the full sequence. Although matches were identified between R. pusillus proteins and proteins from allergenic food sources, the matches were limited to minor allergens from these sources, and they shared a greater degree of sequence homology with those from commonly consumed foods and human proteins. Based on the in silico analysis and a literature review for the source organism, the risk of allergenic cross-reactivity of R. pusillus is low.
Topics: Allergens; Rhizomucor; Humans; Biomass; Food Ingredients; Computer Simulation; Food Hypersensitivity; Fungal Proteins
PubMed: 38657894
DOI: 10.1016/j.yrtph.2024.105629 -
Colloids and Surfaces. B, Biointerfaces Jun 2024In this study, the critical importance of designing an appropriate immobilized carrier and method for free lipase to ensure exceptional biological catalytic activity and...
In this study, the critical importance of designing an appropriate immobilized carrier and method for free lipase to ensure exceptional biological catalytic activity and stability was emphasized. Covalent organic frameworks (COF-1) were synthesized as a novel porous carrier with an azine structure (-CN-NC-) through the condensation of hydrazine hydrate and benzene-1,3,5-tricarbaldehyde at room temperature. Simultaneously, Rhizomucor miehei lipase (RML) was immobilized within the COF-1 carrier using an in-situ aqueous phase method. Characterization of the carrier and RML@COF-1 and evaluation of the lipase properties of RML and RML@COF-1 through p-Nitrophenyl palmitate hydrolysis were conducted. Additionally, application in the synthesis of 1, 3-dioleoyl-2-palmitoylglycerol (OPO) was explored. The results showed that RML@COF-1 exhibited a high enzymatic loading of 285.4 mg/g. Under 60℃ conditions, the activity of RML@COF-1 was 2.31 times higher than that of free RML, and RML@COF-1 retained 77.25% of its original activity after 10 cycles of repeated use, indicating its excellent thermal stability and repeatability. Under the optimal conditions (10%, 1:8 PPP/OA, 45℃, 5 h), the yield of OPO reached 47.35%, showcasing the promising application prospects of the novel immobilized enzyme synthesized via in-situ aqueous phase synthesis for OPO preparation.
Topics: Lipase; Enzymes, Immobilized; Rhizomucor; Metal-Organic Frameworks; Hydrolysis; Porosity; Surface Properties; Triglycerides
PubMed: 38552410
DOI: 10.1016/j.colsurfb.2024.113873 -
Marine Drugs Feb 2024Low levels of docosahexaenoic acid (DHA) in the brain have been related to neurological disorders, like Alzheimer's disease (AD). After ingestion, dietary DHA must cross...
Low levels of docosahexaenoic acid (DHA) in the brain have been related to neurological disorders, like Alzheimer's disease (AD). After ingestion, dietary DHA must cross the blood-brain barrier, where it is absorbed as lysophosphatidylcholine (LPC), due to its role as a preferential DHA carrier in the brain. This work aimed at the production of LPC-DHA extracts to be used in supplementation/food fortification intended neural enrichment in DHA. As it is rich in DHA, especially its phospholipids (PL), Atlantic mackerel (, caught in Spring/2022) was used as a raw material. The polar lipids fraction was separated and hydrolysed with lipase, to enzymatically convert phosphatidylcholine (PC) into LPC. The fish (muscle and by-products) lipids fraction was used for total lipids (TL) content, lipid classes (LC) and fatty acid (FA) profile evaluation, whilst polar lipids extracts were studied for LC production and FA analysis. Muscle TL ranged between 1.45 and 4.64 g/100 g (WW), while by-products accounted for 7.56-8.96 g/100 g, with the highest contents being found in March. However, PL were more abundant in muscle (22.46-32.20% of TL). For polar lipids extracts, PL represented 50.79% of TL, among which PC corresponded to 57.76% and phosphatidylethanolamine to 42.24%. After hydrolysis, nearly half of this PC was converted into LPC. When compared to the initial PC, DHA relative content (33.6% of total FA) was significantly higher after hydrolysis: 55.6% in PC and 73.6% in LPC. Such extract, obtained from this undervalued species, may represent a promising strategy to increase DHA uptake into brain cells while allowing this species to upgrade.
Topics: Animals; Phospholipids; Docosahexaenoic Acids; Brain; Blood-Brain Barrier; Phosphatidylcholines; Fatty Acids; Lysophosphatidylcholines
PubMed: 38535457
DOI: 10.3390/md22030116 -
International Journal of Biological... May 2024In this work, the adsorption of Candida antarctica B (CALB) and Rhizomucor miehei (RML) lipases into hydrophobic wrinkled silica nanoparticles (WSNs) is investigated....
In this work, the adsorption of Candida antarctica B (CALB) and Rhizomucor miehei (RML) lipases into hydrophobic wrinkled silica nanoparticles (WSNs) is investigated. WSNs are hydrophobized by chemical vapor deposition. Both proteins are homogeneously distributed inside the pores of the nanoparticles, as confirmed by Transmission Electron Microscopy and Energy Dispersive X-ray measurements. The maximum enzyme load of CALB is twice that obtained for RML. Fourier Transform Infrared Spectroscopy confirms the preservation of the enzyme secondary structure after immobilization for both enzymes. Adsorption isotherms fit to a Langmuir model, resulting in a binding constant (K) for RML 4.5-fold higher than that for CALB, indicating stronger binding for the former. Kinetic analysis reveals a positive correlation between enzyme load and RML activity unlike CALB where activity decreases along the enzyme load increases. Immobilization allows for enhancing the thermal stability of both lipases. Finally, CALB outperforms RML in the hydrolysis of ethyl-3-hydroxybutyrate. However, immobilized CALB yielded 20 % less 3-HBA than free lipase, while immobilized RML increases 3-fold the 3-HBA yield when compared with the free enzyme. The improved performance of immobilized RML can be explained due to the interfacial hyperactivation undergone by this lipase when immobilized on the superhydrophobic surface of WSNs.
Topics: Enzymes, Immobilized; Lipase; Silicon Dioxide; Hydrophobic and Hydrophilic Interactions; Nanoparticles; Enzyme Stability; Adsorption; Kinetics; Rhizomucor; Fungal Proteins; Hydrolysis; Temperature
PubMed: 38522688
DOI: 10.1016/j.ijbiomac.2024.131022