Enhanced production of natural yellow pigments from Monascus purpureus by liquid culture: The relationship between fermentation conditions and mycelial morphology

To define the relationship between renal epidermal growth factor (EGF) expression and thyroid hormones in acute renal failure, we performed an analysis of the renal thyroid hormone-EGF axis following acute ischemic renal injury in rats. Levels of mature EGF extractable from kidney were elevated 24 h postinjury, and levels of membrane-associated EGF precursor were reduced. Administration of triodothyronine (T3) to rats, either prior to or immediately following the induction of injury, did not further increase levels of extractable EGF. Levels of EGF mRNA in kidneys were reduced 24 h following acute ischemic damage and not affected by administration of T3. Enhanced production of mature EGF from EGF precursor occurred in membranes isolated from kidneys of rats 24 h postinjury compared with production in membranes from kidneys of normal rats. In addition, levels of thyroxine 5'-deiodinase activity in renal membranes were increased 24 h following injury. Levels of circulating total thyroxine (T4), free T4, and free T3 were reduced postischemic injury. Total T3 was unchanged. The administration of T3 to normal rats increased renal 5'-deiodinase activity and EGF precursor cleavage. Administration of propylthiouracil to rats inhibited renal 5'-deiodinase activity and prevented the increase in extractable EGF postischemic injury. We conclude that the increase in levels of mature EGF extractable from kidneys of rats postischemic injury results from enhanced activity of the serine protease that cleaves the EGF precursor. This activity may be stimulated by T3 produced in kidney. These alterations in renal T4 metabolism and EGF expression could serve to facilitate recovery of renal function following ischemia.

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Model-Based Relationship between the Molecular Bacterial Load Assay and Time to Positivity in Liquid Culture

Antimicrobial Agents and Chemotherapy ◽

10.1128/aac.00652-19 ◽

2019 ◽

Vol 63 (10) ◽

Cited By ~ 1

Author(s):

Robin J. Svensson ◽

Wilber Sabiiti ◽

Gibson S. Kibiki ◽

Nyanda E. Ntinginya ◽

Nilesh Bhatt ◽

...

Keyword(s):

Liquid Culture ◽

Good Description ◽

Bacterial Load ◽

Total Sample ◽

Bacterial Killing ◽

Indicator Tube ◽

Time To Positivity ◽

Biomarker Response ◽

Mycobacterial Growth ◽

The Relationship

ABSTRACT The molecular bacterial load (MBL) assay is a new tuberculosis biomarker which provides results in ∼4 hours. The relationship between MBL and time-to-positivity (TTP) has not been thoroughly studied, and predictive models do not exist. We aimed to develop a model for MBL and identify the MBL-TTP relationship in patients. The model was developed on data from 105 tuberculosis patients from Malawi, Mozambique, and Tanzania with joint MBL and TTP observations quantified from patient sputum collected for 12 weeks. MBL was quantified using PCR of mycobacterial RNA and TTP using the mycobacterial growth indicator tube (MGIT) 960 system. Treatment consisted of isoniazid, pyrazinamide, and ethambutol in standard doses together with rifampin 10 or 35 mg/kg of body weight. The developed MBL-TTP model included several linked submodels, a component describing decline of bacterial load in sputum, another component describing growth in liquid culture, and a hazard model translating bacterial growth into a TTP signal. Additional components for contaminated and negative TTP samples were included. Visual predictive checks performed using the developed model gave good description of the observed data. The model predicted greater total sample loss for TTP than MBL due to contamination and negative samples. The model detected an increase in bacterial killing for 35 versus 10 mg/kg rifampin (P = 0.002). In conclusion, a combined model for MBL and TTP was developed that described the MBL-TTP relationship. The full MBL-TTP model or each submodel was used separately. Second, the model can be used to predict biomarker response for MBL given TTP data or vice versa in historical or future trials.

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Enhanced production of Fumigaclavine C in liquid culture of Aspergillus fumigatus under a two-stage process

Bioresource Technology ◽

10.1016/j.biortech.2013.10.089 ◽

2014 ◽

Vol 152 ◽

pp. 162-168 ◽

Cited By ~ 13

Author(s):

Yi-Xiang Zhu ◽

Ling-Yun Yao ◽

Rui-Hua Jiao ◽

Yan-Hua Lu ◽

Ren-Xiang Tan

Keyword(s):

Aspergillus Fumigatus ◽

Liquid Culture ◽

Two Stage ◽

Enhanced Production ◽

Stage Process

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Ammonium nitrate regulated the color characteristic changes of pigments in Monascus purpureus M9

AMB Express ◽

10.1186/s13568-020-01165-6 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Di Chen ◽

Yurong Wang ◽

Mianhua Chen ◽

Pei Fan ◽

Guiling Li ◽

...

Keyword(s):

Ammonium Nitrate ◽

Food Industry ◽

Ph Value ◽

Extracellular Polysaccharide ◽

Monascus Purpureus ◽

Polysaccharide Biosynthesis ◽

Real Time Quantitative Pcr ◽

Color Characteristics ◽

Different Color ◽

Yellow Pigments

AbstractMonascus pigments (MPs) with different color characteristics, produced by submerged fermentation of Monascus purpureus M9, have potential application in food industry. In the present study, the effects and regulatory mechanisms of ammonium nitrate (AN) on the color characteristics of MPs were investigated. The concentration of intracellular pigments was significantly decreased when subjected to AN. The hue and lightness value indicated AN altered the total pigments appearance from original red to orange. The HPLC analysis for six major components of MPs showed that the production of rubropunctatin or monascorubrin, was significantly reduced to the undetectable level, whereas the yields of monascin, ankaflavin, rubropunctamine and monascorubramine, were apparently increased with AN supplement. To be noted, via real-time quantitative PCR strategy, the expression level of mppG, closely relative to orange pigments biosynthesis, was significantly down-regulated. However, the expression of mppE, involved in yellow pigments pathway, was up-regulated. Moreover, the broth pH value was dropped to 2.5–3.5 in the fermentation process resulted from AN treatment, along with the increased extracellular polysaccharide biosynthesis. Taken together, the change of MPs categories and amounts by AN might be the driving force for the color characteristics variation in M. purpureus M9. The present study provided useful data for producing MPs with different compositions and modified color characteristics.

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