Medium optimization and downstream process design for the augmented yield of β-Carotene using fungi Blakeslea trispora

2021 ◽  
Vol ahead-of-print (ahead-of-print) ◽  
Author(s):  
Umesh Luthra ◽  
Prabhakar Babu ◽  
Remya R.R. ◽  
Angeline Julius ◽  
Yogesh Patel ◽  
...  
Keyword(s):  
Process Design ◽  
Medium Optimization ◽  
Corn Starch ◽  
Uv Spectroscopy ◽  
Maximum Activity ◽  
Blakeslea Trispora ◽  
Content Type ◽  
Natural Oils ◽  
Lower Temperature ◽  
Β Carotene

Purpose β-Carotene is the most appropriate and significant precursor of vitamin A. Synthetic carotene supplements have been known to pose a threat to human health, making natural sources such as the indefensible choice for the production and extraction of carotene. Design/methodology/approach This study considers Blakeslea trispora, a filamentous fungus, as a source of production of carotenoids by fermentation and wet and dry mycelium were used to analyse and obtain better extraction results. Findings In this study, natural oils such as soy oil and cottonseed oil were incorporated into fermentation media to increase the production of carotene. For the optimization process, Plackett–Burman and one-factor-at-a-time (OVAT) models were identified as being of great value. Originality/value OVAT was carried out for corn starch because it plays a major role in the production of carotene and the corn starch at 30 g/L concentration has shown the maximum activity of 3.48 mg/gm. After optimizing process variables, submerged fermentation was eventually carried out under highly controlled media conditions. The resulting product was quantified using UV spectroscopy and extraction of carotene has been observed in the presence of various solvents. Among a range of solvents used, the methylene Di chloride produced-carotene at 86% recovery at a significantly lower temperature of 35°C.

Optimizing β-carotene production by Blakeslea trispora using bug damaged wheat

2018 ◽  
Vol 47 (3) ◽  
pp. 189-195
Author(s):  
Serap Durakli Velioglu ◽  
Goksel Tirpanci Sivri
Keyword(s):  
Response Surface Methodology ◽  
Industrial Waste ◽  
Design Methodology ◽  
Model Fit ◽  
Quadratic Model ◽  
Blakeslea Trispora ◽  
Natural Food ◽  
Control Medium ◽  
Content Type ◽  
Β Carotene

Purpose β-carotene, found naturally in many foods, has been widely used as a colourant in various products. The aim of this study is to optimize the production of β-carotene by Blakeslea trispora using bug-damaged wheat as the main nitrogen and carbon source. Design/methodology/approach Response surface methodology (RSM) has been used to determine the optimum concentrations of media components for the maximum β-carotene production. β-carotene concentration was determined quantitively using a spectrophotometric method. Findings A full quadratic model fit the data best for β-carotene production with a high R2 value (0.999). Using optimized media increased the production of β-carotene by B. trispora DSM-2387 and B. trispora DSM-2388 to a higher level (250.407 mg/l) than the control medium (72.195 mg/l). Originality/value This study showed that bug-damaged wheat, an agro-industrial waste having low economical value, may be used as a valuable substrate for microbial production of β-carotene, a natural food colourant possessing high economical value.

scholarly journals Early and Late Trisporoids Differentially Regulate β-Carotene Production and Gene Transcript Levels in the Mucoralean Fungi Blakeslea trispora and Mucor mucedo

2013 ◽  
Vol 79 (23) ◽  
pp. 7466-7475 ◽  
Author(s):  
Yamuna Sahadevan ◽  
Mareike Richter-Fecken ◽  
Kerstin Kaerger ◽  
Kerstin Voigt ◽  
Wilhelm Boland
Keyword(s):  
Life Cycles ◽  
Regulatory Function ◽  
Blakeslea Trispora ◽  
Gene Transcript ◽  
Carotenoid Cleavage Dioxygenase ◽  
Developmental Phase ◽  
Acid Biosynthesis ◽  
Content Type ◽  
Mucor Mucedo ◽  
Β Carotene

ABSTRACTThe multistep cleavage of carotenoids inMucoralesduring the sexual phase results in a cocktail of trisporic acid (C18) sex pheromones. We hypothesized that the C18trisporoid intermediates have a specific regulatory function for sex pheromone production and carotenogenesis that varies with genus/species and vegetative and sexual phases of their life cycles. Real-time quantitative PCR kinetics determined forBlakeslea trisporadisplayed a very high transcript turnover in the gene for carotenoid cleavage dioxygenase,tsp3, during the sexual phase. Anin vivoenzyme assay and chromatographic analysis led to the identification of β-apo-12′-carotenal as the first apocarotenoid involved in trisporic acid biosynthesis inB. trispora. Supplementation of C18trisporoids, namely D'orenone, methyl trisporate C, and trisporin C, increasedtsp3transcripts in the plus compared to minus partners. Interestingly, thetsp1gene, which is involved in trisporic acid biosynthesis, was downregulated compared totsp3irrespective of asexual or sexual phase. Only the minus partners of bothB. trisporaandMucor mucedohad enhanced β-carotene production after treatment with C20apocarotenoids, 15 different trisporoids, and their analogues. We conclude that the apocarotenoids and trisporoids influence gene transcription and metabolite production, depending upon the fungal strain, corresponding genus, and developmental phase, representing a “chemical dialect” during sexual communication.

Numerical treatment for Darcy–Forchheimer flow of nanofluid due to a rotating disk with convective heat and mass conditions

2018 ◽  
Vol 28 (11) ◽  
pp. 2531-2550 ◽  
Author(s):  
T. Hayat ◽  
Arsalan Aziz ◽  
Taseer Muhammad ◽  
A. Alsaedi
Keyword(s):  
Biot Number ◽  
Design Methodology ◽  
Rotating Disk ◽  
Random Motion ◽  
Shooting Technique ◽  
Content Type ◽  
Forchheimer Number ◽  
Opposite Trend ◽  
Lower Temperature ◽  
Forchheimer Flow

Purpose The purpose of this study is to examine the Darcy–Forchheimer flow of viscous nanoliquid because of a rotating disk. Thermophoretic diffusion and random motion aspects are retained. Heat and mass transfer features are analyzed through convective conditions. Design/methodology/approach The governing systems are solved numerically by the shooting technique. Findings Higher porosity parameter and Forchheimer number Fr depict similar trend for both velocity profiles f' and g. Both temperature and concentration profiles show increasing behavior for higher Forchheimer number Fr. An increase in Prandtl number Pr corresponds to lower temperature profile, while opposite trend is noticed for thermal Biot number. Larger concentration Biot number exhibits increasing behavior for both concentration and its associated layer thickness. Originality/value To the best of the author’s knowledge, no such consideration has been given in the literature yet.

scholarly journals Blakeslea trispora Photoreceptors: Identification and Functional Analysis

2020 ◽  
Vol 86 (8) ◽  
Author(s):  
Wei Luo ◽  
Chao Xue ◽  
Yuzheng Zhao ◽  
Huili Zhang ◽  
Zhiming Rao ◽  
...  
Keyword(s):  
Large Scale ◽  
Binding Domain ◽  
Site Directed Mutagenesis ◽  
Flavin Mononucleotide ◽  
Blakeslea Trispora ◽  
Scale Production ◽  
Bioinformatics Analyses ◽  
Content Type ◽  
Flavin Binding

ABSTRACT Blakeslea trispora is an industrial fungal species used for large-scale production of carotenoids. However, B. trispora light-regulated physiological processes, such as carotenoid biosynthesis and phototropism, are not fully understood. In this study, we isolated and characterized three photoreceptor genes, btwc-1a, btwc-1b, and btwc-1c, in B. trispora. Bioinformatics analyses of these genes and their protein sequences revealed that the functional domains (PAS/LOV [Per-ARNT-Sim/light-oxygen-voltage] domain and zinc finger structure) of the proteins have significant homology to those of other fungal blue-light regulator proteins expressed by Mucor circinelloides and Neurospora crassa. The photoreceptor proteins were synthesized by heterologous expression in Escherichia coli. The chromogenic groups consisting of flavin adenine dinucleotide (FAD) and flavin mononucleotide (FMN) were detected to accompany BTWC-1 proteins by using high-performance liquid chromatography (HPLC) and fluorescence spectrometry, demonstrating that the proteins may be photosensitive. The absorbance changes of the purified BTWC-1 proteins seen under dark and light conditions indicated that they were light responsive and underwent a characteristic photocycle by light induction. Site-directed mutagenesis of the cysteine residual (Cys) in BTWC-1 did not affect the normal expression of the protein in E. coli but did lead to the loss of photocycle response, indicating that Cys represents a flavin-binding domain for photon detection. We then analyzed the functions of BTWC-1 proteins by complementing btwc-1a, btwc-1b, and btwc-1c into the counterpart knockout strains of M. circinelloides for each mcwc-1 gene. Transformation of the btwc-1a complement into mcwc-1a knockout strains restored the positive phototropism, while the addition of btwc-1c complement remedied the deficiency of carotene biosynthesis in the mcwc-1c knockout strains under conditions of illumination. These results indicate that btwc-1a and btwc-1c are involved in phototropism and light-inducible carotenogenesis. Thus, btwc-1 genes share a conserved flavin-binding domain and act as photoreceptors for control of different light transduction pathways in B. trispora. IMPORTANCE Studies have confirmed that light-regulated carotenogenesis is prevalent in filamentous fungi, especially in mucorales. However, few investigations have been done to understand photoinduced synthesis of carotenoids and related mechanisms in B. trispora, a well-known industrial microbial strains. In the present study, three photoreceptor genes in B. trispora were cloned, expressed, and characterized by bioinformatics and photoreception analyses, and then in vivo functional analyses of these genes were constructed in M. circinelloides. The results of this study will lead to a better understanding of photoreception and light-regulated carotenoid synthesis and other physiological responses in B. trispora.

scholarly journals Role of the Phenylalanine-Hydroxylating System in Aromatic Substance Degradation and Lipid Metabolism in the Oleaginous Fungus Mortierella alpina

2013 ◽  
Vol 79 (10) ◽  
pp. 3225-3233 ◽  
Author(s):  
Hongchao Wang ◽  
Haiqin Chen ◽  
Guangfei Hao ◽  
Bo Yang ◽  
Yun Feng ◽  
...  
Keyword(s):  
Lipid Metabolism ◽  
High Performance ◽  
Phenylalanine Hydroxylase ◽  
Uv Spectroscopy ◽  
Dry Weight ◽  
Life Forms ◽  
Mortierella Alpina ◽  
Content Type ◽  
Gene Copies ◽  
Aromatic Substance

ABSTRACTMortierella alpinais a filamentous fungus commonly found in soil that is able to produce lipids in the form of triacylglycerols that account for up to 50% of its dry weight. Analysis of theM. alpinagenome suggests that there is a phenylalanine-hydroxylating system for the catabolism of phenylalanine, which has never been found in fungi before. We characterized the phenylalanine-hydroxylating system inM. alpinato explore its role in phenylalanine metabolism and its relationship to lipid biosynthesis. Significant changes were found in the profile of fatty acids inM. alpinagrown on medium containing an inhibitor of the phenylalanine-hydroxylating system compared toM. alpinagrown on medium without inhibitor. Genes encoding enzymes involved in the phenylalanine-hydroxylating system (phenylalanine hydroxylase [PAH], pterin-4α-carbinolamine dehydratase, and dihydropteridine reductase) were expressed heterologously inEscherichia coli, and the resulting proteins were purified to homogeneity. Their enzymatic activity was investigated by high-performance liquid chromatography (HPLC) or visible (Vis)-UV spectroscopy. Two functional PAH enzymes were observed, encoded by distinct gene copies. A novel role for tetrahydrobiopterin in fungi as a cofactor for PAH, which is similar to its function in higher life forms, is suggested. This study establishes a novel scheme for the fungal degradation of an aromatic substance (phenylalanine) and suggests that the phenylalanine-hydroxylating system is functionally significant in lipid metabolism.

scholarly journals Draft Genome Sequence of the Green Alga Scenedesmus acuminatus SAG 38.81

2020 ◽  
Vol 9 (24) ◽  
Author(s):  
Yekaterina Astafyeva ◽  
Malik Alawi ◽  
Daniela Indenbirken ◽  
Dominik Danso ◽  
Adam Grundhoff ◽  
...  
Keyword(s):  
Fatty Acids ◽  
Genome Sequence ◽  
Draft Genome ◽  
Whole Genome Sequence ◽  
Whole Genome ◽  
Content Type ◽  
Green Microalga ◽  
Scenedesmus Acuminatus ◽  
Valuable Compounds ◽  
Β Carotene

ABSTRACT Scenedesmus acuminatus, also known as Tetradesmus acuminatus, is a promising green microalga for sustainable production of microalga products, including valuable compounds such as astaxanthin, β-carotene, and lutein, polysaccharides such as β-glucan, and polyunsaturated fatty acids. Here, we report the draft whole-genome sequence of Scenedesmus acuminatus SAG 38.81.

Comparative analysis of back-to-back subcontracts in the construction and telecommunications industries

2015 ◽  
Vol 5 (4) ◽  
pp. 446-460 ◽  
Author(s):  
Lars-Henrik Kvist Nielsen ◽  
Abiola Akanmu ◽  
Chimay J. Anumba
Keyword(s):  
Comparative Analysis ◽  
Process Design ◽  
Business Strategy ◽  
Supplier Management ◽  
Content Type ◽  
Corporate Strategies ◽  
Project Construction ◽  
Telecommunications Industries ◽  
Common Understanding ◽  
Typical Model

Purpose – “Back-to-back” contracts are widely used in the engineering and construction industry and are recently spreading into the telecommunication industry. In back-to-back contracts, the principals require the main contractors to assume majority of the liability in delivering a project and in turn, the main contractors try to allocate most of that liability to their subcontractors. The successful delivery of the projects hinges on how the contracts are drafted and risks are allocated between the parties involved. The purpose of this paper is to undertake a comparative analysis of “back-to-back” subcontracts in the telecommunication and construction industries. Design/methodology/approach – By examining contracting practices and texts from contract documents for the telecommunication and construction industries, this paper reveals how certain aspects of “back-to-back” contracts lose their meaning when seen out of context. Using comparative research method, this paper discusses reasons why the adoption of “back-to-back” contracts should be a matter of degree, based on the business strategy and relevance to the intended transactions rather than on the typical model of “back-to-back” contracts. Findings – Good contracting practices should be such as to enable parties negotiate the contract terms to ensure clarity and common understanding before commencing the project. Construction universally adopts back-to-back even for minor straightforward works, an approach supported by readily available industry model contracts as well as the traditional tender process (design before construction). In telecoms, back-to-back is mainly desired where the subcontractor has a major part of the scope, whereas minor subcontractor scope is considered “leverage commodity” where suppliers are engaged using in-house contract templates, often in a frame contract arrangement, to satisfy corporate strategies for supplier management and pricing. Originality/value – This paper provides value by presenting an insightful review of the nature of back-to-back contracting practices in the telecommunication and construction industries. The paper outlines advantages, disadvantages and opportunities for improving “back-to-back” contracting practices in the telecommunication and construction industries.

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