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Indian Journal of Dermatology 2021Mucormycosis is an invasive fungal infection that has been increasing in incidence over the years. Increase in the number of diabetics, malignancy patients, and use of... (Review)
Review
Mucormycosis is an invasive fungal infection that has been increasing in incidence over the years. Increase in the number of diabetics, malignancy patients, and use of immunosuppressants has mainly led to this gradual upward surge. Mucormycosis has various clinical forms, including rhino-orbito-cerebral, pulmonary, gastrointestinal, and cutaneous. Fungi belonging to Mucorales are thermotolerant and ubiquitous, found growing on organic substrates such as bread, decaying fruits and vegetables, crop debris in soil, compost, and animal excreta. During this second wave of the COVID-19 pandemic, the number of cases of mucormycosis has increased manifold in a short span of time. Associated comorbidity of diabetes mellitus, increased use of higher doses and prolonged duration of systemic corticosteroids, the glucogenic and prothrombotic propensity of the virus, hypoxic environment, COVID pneumonia, increased hospitalization, ICU admissions, and mechanical ventilation have all contributed toward this high rise in numbers. The rhin-orbito-cerebral form is the commonest manifestation of mucormycosis in COVID. , the main species causing mucormycosis, is identified by hyaline, sparsely-septate, broad, ribbon-like hyphae with irregular right-angle branching ribbon-like hyphae with rhizoids. For the early diagnosis of this infection, 10% KOH mount is very important. These fungi are very rapidly growing and thus can be differentiated from their main ally, Aspergillus. Treatment is mainly in the form of extensive surgical debridement along with liposomal amphotericin B. Posaconazole and isavuconazole are second-line agents, which can also be used for maintenance. Control of diabetes and COVID-19, along with judicious use of antibiotics and systemic corticosteroids, are equally important as management strategies in these pandemic times.
PubMed: 34759398
DOI: 10.4103/ijd.ijd_477_21 -
Clinical Infectious Diseases : An... Feb 2012Mucormycosis is a life-threatening infection that occurs in patients who are immunocompromised because of diabetic ketoacidosis, neutropenia, organ transplantation,... (Review)
Review
Mucormycosis is a life-threatening infection that occurs in patients who are immunocompromised because of diabetic ketoacidosis, neutropenia, organ transplantation, and/or increased serum levels of available iron. Because of the increasing prevalence of diabetes mellitus, cancer, and organ transplantation, the number of patients at risk for this deadly infection is increasing. Despite aggressive therapy, which includes disfiguring surgical debridement and frequently adjunctive toxic antifungal therapy, the overall mortality rate is high. New strategies to prevent and treat mucormycosis are urgently needed. Understanding the pathogenesis of mucormycosis and the host response to invading hyphae ultimately will provide targets for novel therapeutic interventions. In this supplement, we review the current knowledge about the virulence traits used by the most common etiologic agent of mucormycosis, Rhizopus oryzae. Because patients with elevated serum levels of available iron are uniquely susceptible to mucormycosis and these infections are highly angioinvasive, emphasis is placed on the ability of the organism to acquire iron from the host and on its interactions with endothelial cells lining blood vessels. Several promising therapeutic strategies in preclinical stages are identified.
Topics: Diabetic Ketoacidosis; Endothelial Cells; Genes, Fungal; Host-Pathogen Interactions; Humans; Immunocompromised Host; Iron; Mucormycosis; Phagocytes; Rhizopus; Risk Factors; Virulence Factors
PubMed: 22247441
DOI: 10.1093/cid/cir865 -
Journal, Genetic Engineering &... Jan 2021Rhizopus species is among the most well-known lipase producers, and its enzyme is suitable for use in many industrial applications. Our research focuses on the...
BACKGROUND
Rhizopus species is among the most well-known lipase producers, and its enzyme is suitable for use in many industrial applications. Our research focuses on the production of lipase utilizing waste besides evaluating its applications.
RESULTS
An extracellular lipase was partially purified from the culture broth of Rhizopus oryzae R1 isolate to apparent homogeneity using ammonium sulfate precipitation followed by desalting via dialysis. The partially purified enzyme was non-specific lipase and the utmost activity was recorded at pH 6, 40 °C with high stability for 30 min. The constants K and V, calculated from the Lineweaver-Burk plot, are 0.3 mg/mL and 208.3 U/mL, respectively. Monovalent metal ions such as Na (1 and 5 mM) and K (5 mM) were promoters of the lipase to enhance its activity with 110, 105.5, and 106.5%, respectively. Chitosan was used as a perfect support for immobilization via both adsorption and cross-linking in which the latter method attained immobilization efficiency of 99.1% and reusability of 12 cycles. The partially purified enzyme proved its ability in forming methyl oleate (biodiesel) through the esterification of oleic acid and transesterification of olive oil.
CONCLUSION
The partially purified and immobilized lipase from Rhizopus oryzae R1 approved excellent efficiency, reusability, and a remarkable role in detergents and biodiesel production.
PubMed: 33400043
DOI: 10.1186/s43141-020-00094-y -
Journal of Food Protection May 2023Electron beam irradiation is a physical fungicidal technique that has emerged as a potential application in China. However, its antifungal activity and mechanism against...
Electron beam irradiation is a physical fungicidal technique that has emerged as a potential application in China. However, its antifungal activity and mechanism against Rhizopus oryzae have not been reported. Thus, this study aimed to investigate the antifungal activity and mechanism of electron beam irradiation of R. oryzae. The antifungal activity analysis showed that the D value and complete elimination dose of R. oryzae irradiated by electron beam were 1.73 kGy and 8.08 kGy, respectively. Electron beam irradiation has a strong inhibitory effect on the filamentous biomass of R. oryzae. To reveal the antifungal mechanism of electron beam against R. oryzae, this study analyzed the dynamic changes in the cell wall, cell membrane, and oxidative stress induced by different irradiation doses. The results showed that electron beam irradiation destroyed the cell wall structure of R. oryzae, increasing chitinase activity and decreasing chitin content. Cell membrane integrity is disrupted, increasing relative conductivity, decreasing pH values, and decreasing soluble protein content. Electron beam irradiation causes oxidative stress in cells, increasing HO content, decreasing antisuperoxide anion activity, decreasing DPPH free radical scavenging activity, and inhibiting defense enzyme (CAT and SOD) activity. This phenomenon indicates that electron beams can cause structural damage to and metabolic dysfunction of cells and disorders of redox homeostasis, which may be the main cause of growth inhibition and cell death in R. oryzae.
Topics: Antifungal Agents; Rhizopus oryzae; Hydrogen Peroxide; Electrons; Rhizopus
PubMed: 36989859
DOI: 10.1016/j.jfp.2023.100070 -
3 Biotech Nov 2020Industrial strains of is known for its strong ability to produce L-( +)-lactic acid, ethanol, and fumaric acid at high yields. To better understand the underlying...
Industrial strains of is known for its strong ability to produce L-( +)-lactic acid, ethanol, and fumaric acid at high yields. To better understand the underlying mechanism behind the physiology of , we conducted the proteome changes between two different morphologies using two-dimensional polyacrylamide gel electrophoresis and mass spectrometry. exhibited pellet morphology and filamentous morphology when the initial pH of the culture medium was 3.0 and 5.0, respectively. The concentration of lactic acid reached 63.5 g L in the samples containing the pellet morphology, compared to 41.5 g L produced by filamentous . Proteomic analysis indicated that expression levels of 128 proteins changed significantly. Of these, 17 protein spots were successfully identified by mass spectrometry and were deemed to be mainly involved in carbohydrate metabolism, genetic information processing, chitin metabolism, protein catabolism, protein folding, and antioxidative pathway. L-lactate dehydrogenase (RO3G_06188), enolase (RO3G_05466) and 2, 3-bisphosphoglycerate-independent phosphoglycerate mutase (RO3G_02462) were found to be upregulated, while isocitrate dehydrogenase (RO3G_13820) was downregulated in the samples with pellet morphology compared to the filamentous hyphae. These results suggested that more carbon flow was directed towards lactic acid biosynthesis in hyphae with pellet morphology.
PubMed: 33088665
DOI: 10.1007/s13205-020-02458-0 -
Scientific Reports Jan 2020We aimed to develop a consortium of starter culture of effective microorganisms to prepare doenjang, a traditional Korean fermented food. Different ratios of Bacillus...
Effect of Rhizopus nigricans (Rhizopus stolonifera)-based novel starter culture on quality and safety attributes of doenjang, a traditional Korean soybean fermented food product.
We aimed to develop a consortium of starter culture of effective microorganisms to prepare doenjang, a traditional Korean fermented food. Different ratios of Bacillus subtilis TKSP 24 (B), Aspergillus oryzae complex (A), Rhizopus nigricans (also named as Rhizopus stolonifera) (R), and Mucor racemosus 15 (M15) were selected as meju starter cultures to produce doenjang with improved quality. Microbial strain combinations (B: A: R and B: M15: R) were mixed separately at three different ratios [1:1:1 (w/w), 1:0.5:1.5 (w/w), and 1:1.5:0.5 (w/w)] to prepare BAR-1, BAR-2, BAR-3, BM15R-1, BM15R-2, and BM15R-3 doenjang samples. Quantitative analyses included free amino acids, free sugar, volatile and non-volatile organic acids, cellular antioxidant activity along with the presence of biogenic amines and aflatoxins, and microbial counts. Total free amino acids responsible for the sweet taste of doenjang were highest in BAR-2 (322.50 mg/100 g) and BM15R-3 (320.07 mg/100 g). Total volatile organic acid was highest in BAR-1 compared to other preparations. All doenjang samples had biogenic amines, especially histamine, below the toxicity level (500 mg/kg). Also, the aflatoxin and hazardous microbial count in the tested doenjang samples were below the level of toxicity. The findings suggest that use of multiple microbial strains in combination with R. nigricans as a starter culture could be a novel and effective approach to improve the nutrition and safety of fermented soybean food products of doenjang.
Topics: Aflatoxins; Amino Acids; Biogenic Amines; Fermentation; Food Microbiology; Food Safety; Quality Control; Republic of Korea; Rhizopus; Soy Foods; Glycine max
PubMed: 31974506
DOI: 10.1038/s41598-019-57382-y -
Microbiology and Immunology Feb 2019Silkworm, Bombyx mori, has various advantages as an experimental animal, such as the low cost for rearing and fewer ethical problems. Models utilizing silkworms of... (Review)
Review
Silkworm, Bombyx mori, has various advantages as an experimental animal, such as the low cost for rearing and fewer ethical problems. Models utilizing silkworms of infection with pathogenic bacteria have been established for identification of genes encoding virulence factors by large-scale in vivo screening. In this review, we describe recent progress in the study of silkworm infection models for elucidating the mechanisms of fungi infection. Silkworm infection models have been established for Candida albicans, Candida tropicalis, Candida glabrata and Cryptococcus neoformans, which are yeast type fungi, and Aspergillus fumigatus, Arthroderma vanbreuseghemii, Arthroderma benhamiae, Microsporum canis, Trichophyton rubrum, and Rhizopus oryzae, which are filamentous fungi. Novel genes encoding virulence factors in C. albicans and C. glabrata have been identified by using the silkworm infection models. We here outline the benefits of using silkworm infection models and a strategy for identifying the genes responsible for pathogenicity of microorganisms such as fungi. © 2019 The Authors. Microbiology and Immunology Published by The Societies and John Wiley & Sons Australia, Ltd.
Topics: Animals; Bacteria; Bombyx; Candida; Candidiasis; Cryptococcosis; Cryptococcus neoformans; Disease Models, Animal; Fungi; Mycoses; Virulence; Virulence Factors
PubMed: 30666711
DOI: 10.1111/1348-0421.12668 -
Biotechnology For Biofuels Dec 2021Rhizopus oryzae (R. oryzae) can effectively produce organic acids, and its pellet formation in seed cultures has been shown to significantly enhance subsequent...
Rhizopus oryzae (R. oryzae) can effectively produce organic acids, and its pellet formation in seed cultures has been shown to significantly enhance subsequent fermentation processes. Despite advances in strain development, simple and effective methods for inducing pellet morphology and a basic understanding of the mechanisms controlling this process could facilitate substantial increases in efficiency and product output. Here, we report that 1.5% triethanolamine (TEOA) in seed culture medium can activate the growth of R. oryzae spores in compact and uniform pellets which is optimal for fermentation conditions. Analysis of fermentation kinetics showed that the production of fumaric and L-malic acid increases 293% and 177%, respectively. Transcriptomic analysis revealed that exposure of R. oryzae to 1.5% TEOA during the seed culture activated the phosphatidylinositol and mitogen-activated protein kinase signaling pathways. Theses pathways subsequently stimulated the downstream carbohydrate-active synthases and hydrolases that required for cell wall component synthesis and reconstruction. Our results thus provide insight into the regulatory pathways controlling pellet morphology germane to the viability of seed cultures, and provide valuable reference data for subsequent optimization of organic acid fermentation by R. oryzae.
PubMed: 34863259
DOI: 10.1186/s13068-021-02081-y -
Food Science & Nutrition Oct 2023Potato peel waste (PPW), a zero-value by-product generated from potato processing, is a promising fermentation substrate due to its large quantity of starch, nonstarch...
Potato peel waste (PPW), a zero-value by-product generated from potato processing, is a promising fermentation substrate due to its large quantity of starch, nonstarch polysaccharides, lignin, protein, and lipid. is a filamentous fungus that is mainly known as a lactic acid producer and can ferment various agro-wastes. This study aimed to use for the fermentation of PPW. A series of batch fermentations were conducted to investigate the effects of different PPW loading rates (2%-8%) and particle sizes (0-4 mm). Under an initial PPW loading rate of 8% and particle size of 1-2 mm, the maximum ethanol (18.83 g/L) and lactic acid (3.14 g/L) concentrations, the highest ethanol (9.41 g/L·day) and lactic acid (1.89 g/L·day) average production rates were obtained. Under these conditions, the yield of ethanol and lactic acid was 0.235 g/gPPW and 0.039 g/gPPW, respectively. was shown to utilize PPW as a substrate to produce value-added bioproducts such as ethanol (major product) and lactic acid.
PubMed: 37823114
DOI: 10.1002/fsn3.3670 -
Infection due to Aspergillus flavus and Rhizopus oryzae complex in a patient with diabetes mellitus.Biomedica : Revista Del Instituto... Mar 2023Fungal sinusitis is a pathology that can occur in patients with diabetes mellitus and be associated with a hyperglycemic crisis. It is an aggressive entity with local...
Fungal sinusitis is a pathology that can occur in patients with diabetes mellitus and be associated with a hyperglycemic crisis. It is an aggressive entity with local complications that include involvement of the orbit or the central nervous system, and vascular involvement. Despite surgical and antifungal treatment, mortality raises up to 75%. We report the case of a female patient with a diagnosis of diabetic ketoacidosis and signs of unilateral ophthalmoplegia, which led to the study with magnetic resonance imaging of the central nervous system, finding signs of sinusitis, meningitis, and cerebritis. Initial microbiological studies were negative, and biomarkers such as serum galactomannan and Cryptococcus antigen were also negative. After surgical management and the identification of Aspergillus flavus and Rhizopus spp. in sinus tissue, the patient received treatment with posaconazole and after two months of follow-up she presented clinical improvement. Dual fungal infection and infection by A. flavus are uncommon and clinically relevant entities, with no cases previously reported in our country, therefore this corresponds to a case of clinical interest.
Topics: Humans; Rhizopus oryzae; Aspergillus flavus; Diabetes Mellitus; Retrospective Studies
PubMed: 37167471
DOI: 10.7705/biomedica.6358