42 research outputs found
Improved 11α-hydroxycanrenone production by modification of cytochrome P450 monooxygenase gene in Aspergillus ochraceus
Eplerenone is a drug that protects the cardiovascular system. 11α-Hydroxycanrenone is a key intermediate in eplerenone synthesis. We found that although the cytochrome P450 (CYP) enzyme system in Aspergillus ochraceus strain MF018 could catalyse the conversion of canrenone to 11α-hydroxycanrenone, its biocatalytic efficiency is low. To improve the efficiency of 11α-hydroxycanrenone production, the CYP monooxygenase-coding gene of MF018 was predicted and cloned based on whole-genome sequencing results. A recombinant A. ochraceus strain MF010 with the high expression of CYP monooxygenase was then obtained through homologous recombination. The biocatalytic rate of this recombinant strain reached 93 % at 60 h without the addition of organic solvents or surfactants and was 17–18 % higher than that of the MF018 strain. Moreover, the biocatalytic time of the MF010 strain was reduced by more than 30 h compared with that of the MF018 strain. These results show that the recombinant A. ochraceus strain MF010 can overcome the limitation of substrate biocatalytic efficiency and thus holds a high potential for application in the industrial production of eplerenone
Effects of aroma quality on the biotransformation of natural 2-phenylethanol produced using ascorbic acid
Background: Natural 2-phenylethanol (2-PE) is an important flavoring
that emits the aroma of roses. During biotransformation, the aroma
quality of natural 2-PE is affected by its main by-products, which
include butanol, isobutyric acid, butyric acid, and isovaleric acid.
Thus, controlling undesirable by-product formation can reduce the
effect of odor on 2-PE aroma quality. Results: 2-PE was produced
through biotransformation using L-phenylalanine as a substrate and
glucose as a carbon source. Ascorbic acid was added to the system to
improve the redox reaction and suppress the generation of by-products.
Principal component analysis of the aroma quality of 2-PE was performed
using an electronic nose. Similarity analysis revealed that the effects
of four by-products on 2-PE aroma quality may be ranked in the
following order: isovaleric acid < butyric acid < isobutyric acid
< butanol. The sample that exhibited the best similarity to the
standard 2-PE sample (99.19%) was the sample to which ascorbic acid had
been added during glucose metabolism. Conclusions: 2-PE produced
through the addition of ascorbic acid exhibited the closest aroma
similarity to the standard 2-PE sample
Percutaneous retrieval of a dislodged watchman left atrial appendage closure device
A 46-year-old female underwent left atrial appendage closure (LAAC) with a Watchman LAAC device. During the procedure, the device embolized into the descending aorta. A new device was implanted to the left atrial appendage complete the closure. The displaced device was successfully snared and removed by Amplatz Goose Neck™ Snare Kit. The patient recovered well and suffered from no clinical sequelae
Biotransformation and Production from Hansenula Anomala to Natural Ethyl Phenylacetate
Ethyl phenylacetate can be widely applied in many industries, such as food, medicines, cosmetics and medicinal herbs. At the moment, the production of natural ethyl phenylacetate is very limited. However, the biotransformation production of natural ethyl phenylacetate has an very extensive application prospect. This paper is written by taking the phenylacetic acid tolerance and the esterifying enzyme activity as the two indexes for screening the HA14 strain of hansenula anomala mutagenic which is regarded as the microorganism of ethyl phenylacetate production through biotransformation. By optimizing the production condition of phenylacetic acid and the esterification condition of ethyl phenylacetate, the production of ethyl phenylacetate accomplished through biotransformation within 72 hours can reach 864mg/L which is 171% of that of the initial bacterial strain
Biotransformation and Production from
Ethyl phenylacetate can be widely applied in many industries, such as food, medicines, cosmetics and medicinal herbs. At the moment, the production of natural ethyl phenylacetate is very limited. However, the biotransformation production of natural ethyl phenylacetate has an very extensive application prospect. This paper is written by taking the phenylacetic acid tolerance and the esterifying enzyme activity as the two indexes for screening the HA14 strain of hansenula anomala mutagenic which is regarded as the microorganism of ethyl phenylacetate production through biotransformation. By optimizing the production condition of phenylacetic acid and the esterification condition of ethyl phenylacetate, the production of ethyl phenylacetate accomplished through biotransformation within 72 hours can reach 864mg/L which is 171% of that of the initial bacterial strain
Chemical renal denervation-induced upregulation of the ACE2/Ang (1-7)/Mas axis attenuates blood pressure elevation in spontaneously hypertensive rats
Objective Evidence has shown that the ACE2/Ang (1–7)/Mas axis plays an important role in the control of hypertension. Thus, we hypothesized that chemical renal denervation (RDN) could reduce blood pressure by regulating the ACE2/Ang (1–7)/Mas axis in spontaneously hypertensive rats. Methods Twelve rats were randomly divided into sham group and chemical RDN group. All the rats were sacrificed 4 weeks later. Plasma samples were collected to measure the renin-angiotensin system (RAS) activities and reactive oxygen species levels by radioimmunoassay, chromatometry and ELISA. Paraventricular nucleus (PVN) tissues were collected to examine the expression of the components of the ACE2/Ang (1–7)/Mas axis by western bolt and immunofluorescence. Results The systolic blood pressure (169.33 ± 7.50 vs 182.67 ± 7.00 mmHg, p < .05) and the diastolic blood pressure (97.50 ± 4.68 vs 109.33 ± 4.41 mmHg, p < .05) in the RDN group were obviously lower than the baseline levels, whereas the opposite results were observed in the sham group. The RDN group exhibited a significant reduction in the plasma ROS (91.59 ± 13.12 vs 72.34 ± 11.76 U/ml, p < .05) and NADPH oxidase (171.86 ± 1.14 vs 175.75 ± 1.74 nmol/ml, p < .001) compared with the sham group, while the plasma eNOS (3.47 ± 0.42 vs 2.49 ± 0.51 U/ml, p < .05) and NO (55.92 ± 8.10 vs 43.53 ± 4.58 μmol/L, p < .05) were increased. The expression of the components of the ACE2/Ang (1–7)/Mas axis was upregulated while the expression of the components of the ACE/Ang II/AT1 R axis was downregulated in the plasma and PVN in the RDN group. Conclusion Our findings suggested that the reduction in blood pressure was regulated by chemical RDN-induced upregulation of the components of the ACE2/Ang (1–7)/Mas axis
Improved 11α-hydroxycanrenone production by modification of cytochrome P450 monooxygenase gene in Aspergillus ochraceus
Eplerenone is a drug that protects the cardiovascular system. 11α-Hydroxycanrenone is a key intermediate in eplerenone synthesis. We found that although the cytochrome P450 (CYP) enzyme system in Aspergillus ochraceus strain MF018 could catalyse the conversion of canrenone to 11α-hydroxycanrenone, its biocatalytic efficiency is low. To improve the efficiency of 11α-hydroxycanrenone production, the CYP monooxygenase-coding gene of MF018 was predicted and cloned based on whole-genome sequencing results. A recombinant A. ochraceus strain MF010 with the high expression of CYP monooxygenase was then obtained through homologous recombination. The biocatalytic rate of this recombinant strain reached 93 % at 60 h without the addition of organic solvents or surfactants and was 17–18 % higher than that of the MF018 strain. Moreover, the biocatalytic time of the MF010 strain was reduced by more than 30 h compared with that of the MF018 strain. These results show that the recombinant A. ochraceus strain MF010 can overcome the limitation of substrate biocatalytic efficiency and thus holds a high poten tial for application in the industrial production of eplerenone
Effects of aroma quality on the biotransformation of natural 2-phenylethanol produced using ascorbic acid
Background: Natural 2-phenylethanol (2-PE) is an important flavoring that emits the aroma of roses. During biotransformation, the aroma quality of natural 2-PE is affected by its main by-products, which include butanol, isobutyric acid, butyric acid, and isovaleric acid. Thus, controlling undesirable by-product formation can reduce the effect of odor on 2-PE aroma quality.
Results: 2-PE was produced through biotransformation using l-phenylalanine as a substrate and glucose as a carbon source. Ascorbic acid was added to the system to improve the redox reaction and suppress the generation of by-products. Principal component analysis of the aroma quality of 2-PE was performed using an electronic nose. Similarity analysis revealed that the effects of four by-products on 2-PE aroma quality may be ranked in the following order: isovaleric acid > butyric acid > isobutyric acid > butanol. The sample that exhibited the best similarity to the standard 2-PE sample (99.19%) was the sample to which ascorbic acid had been added during glucose metabolism.
Conclusions: 2-PE produced through the addition of ascorbic acid exhibited the closest aroma similarity to the standard 2-PE sample