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Free enzymes often face economic problems because of their non-repeatability and variability, which limit their application in industrial production. In this study, KDN lipase was immobilized with the macroporous resin LXTE-1000 and glutaraldehyde. The optimal conditions of enzyme immobilization were defined by a single factor experiment and response surface methodology (RSM). The concentration of the cross-linking agent glutaraldehyde was 0.46% (v/v), the cross-linking temperature was 25.0 °C, and the cross-linking time was 157 min. The enzyme activity of the immobilized KDN lipase after adsorption/cross-linking was 291.36 U/g, and the recovery of the enzyme activity was 9.90%. The optimal conditions for the synthesis of isopropyl myristate were catalyzed by the immobilized KDN lipase in a solvent-free system: immobilized enzyme 53 mg, reaction temperature 36.1 °C, myristic acid 228.4 mg, isopropanol 114 µL, and reaction time 18 h. The yield of isopropyl myristate was 66.62%. After ten cycles, the activity of the immobilized KDN lipase preserved more than 46.87% of its initial enzyme activity, and it demonstrated high tolerance to solvents compared to free KDN lipase.

To explore the potential metabolites from rabeprazole sulfide, seven strains of filamentous fungi were screened for their biotransformation abilities. Among these strains, Cunninghamella blakesleeana 3.970 exhibited the best result. Four different culture media were screened in order to identify the most optimal for subsequent research. Single factors such as the initial pH of culture media, culture time, inoculation volume, and media volume were individually investigated to provide the optimum biotransformation conditions. Then, an orthogonal optimization process using a five-factor, four-level L16(45) experiment was designed and performed. Finally, when the substrate concentration is 3 g/L, one major metabolite was detected with a transformation rate of 72.4%. Isolated by semipreparative HPLC, this metabolite was further detected by ESI-MS and NMR. The final data analysis indicated that the metabolite is O-demethylation rabeprazole sulfide.

Trans-cinnamic acid and p-coumaric acid are valuable intermediates in the synthesis of flavonoids and are widely employed in food, flavor and pharmaceutical industries. These products can be produced by the deamination of L-phenylalanine and L-tyrosine catalyzed by phenylalanine ammonia lyase or tyrosine ammonia lyase. Phenylalanine ammonia-lyase (PAL, EC 4.3.1.5) from Rhodotorula glutinis do not exhibit strong substrate specificity and can convert both L-phenylalanine and L-tyrosine. In this study, the PAL was utilized as the whole-cell biocatalyst, and the reaction conditions were optimized, and the production of trans-cinnamic acid and p-coumaric acid of 597 mg/L and 525 mg/L were achieved with high purity (>98%).

The hydroxylation of dehydroepiandrosterone (DHEA) to 7α -hydroxy-5-androstene-17-one (7α-OH-DHEA) and 7β-hydroxy-5-androstene-17-one (7β-OH-DHEA) by Gibberella sp. CICC 2498 and Absidia coerulea CICC 41050 was investigated. The media ingredients were optimized. Single factors such as the DHEA concentration, culture time, medium volume, and inoculum rate were individually investigated to generate optimum biotransformation conditions. An orthogonal optimization process using a four-factor, three- level L9 (33) experiment was designed and performed. Finally, the maximum production of 7β-OH-DHEA from DHEA biotransformation by Absidia coerulea is 69.61%. This strategy would provide a possible way to enhance the 7β-OH-DHEA yield in the pharmaceutical industry.

Streptomyces noursei D-3-14 was taken as a starting strain and treated with UV (15 W, 30 cm) mutagenesis for 40 s for three consecutive rounds. High yielding strains were screened using chemical and biological potency determination, and the components of the fermentation products were detected using HPLC. Finally, the mutant strain Streptomyces noursei 72-22-1 with a chemical potency of 8912 (U/mL) and a biological potency of 5557 (U/mL) was obtained after the genetic stability evaluation. After optimization of the fermentation conditions, the chemical potency and biological potency of Streptomyces noursei 72-22-1 reached 14,082 U/mL and 10579 U/mL, respectively, which is 1.58 and 1.91 times those before optimization. HPLC analysis indicated that the mutant strain 72-22-1 displayed a higher content of polyfungin B. When equimolar nystatin A1, A3, and polyfungin B were tested for their fungicidal activities towards Saccharomyces cerevisiae ATCC 2061, polyfungin B exhibited a better efficacy than nystatin A1 and A3.

Mycoplasma pneumoniae(MP) is a leading pathogen of respiratory infection, especially community-acquired pneumonia (CAP), in children worldwide. However, its diagnosis is frequently ineffective because bacterial culture and serology test are usually positive 1–2 weeks or more after the disease onset. To achieve a better detection efficiency, the single-walled carbon nanotubes(SWCNT) were coupled with the colloidal gold-monoclonal antibody immunochromatographic strips(CGIC). Interestingly, the SWCNT/CGIC assay allowed MP identification, with a detection limit of 1 × 102 copies/ml. Using referenced throat swabs of 97 MP and 40 non-MP cases, the assay yielded 72.2% sensitivity, 100.0% specificity, 100.0% positive predictive value (PPV), 59.7% negative predictive value (NPV). In summary, our assay was far more effective than any conventional methods for the diagnosis of acute MP. The ease of use, rapid and stability further enhance its feasibility for clinical use on-site.

We used 2D-PAGE to isolate a light-induced protein (AL-A) that is expressed abundantly in light-growth alfalfa sprouts. The seven amino acids of the N-terminal region of the protein were identified, and we searched for the protein in GenBank using the BLAST program. The results of the homology analysis showed that the amino acid sequence of the isolated protein is most similar to one from a pea plastocyanin. To identify the protein, we amplified and sequenced the DNA fragment encoding AL-A from genomic alfalfa DNA. We found that the AL-A gene was highly homologous (90%) to the sequences from the pea plastocyanin via multiple alignments, and the deduced protein precursor was predicted to be chloroplast-specific via the ChloroP computer program. The protein was named alfalfa-plastocyanin (AL-P). It was characterized as being a light-inducible protein, and RT-PCR analysis showed that AL-P mRNA transcription only occurred in the leaves of the alfalfa plant and the alfalfa seedlings growth in lighted conditions. PCR was also used to amplify the DNA fragment encoding the AL-P promoter (AL-Pp) from genomic alfalfa DNA. PlantCARE analysis of the promoter sequence indicated that both a typical TATA box and a CAAT box were located in the promoter sequence, and some of the cis-elements that are responsible for light responsiveness were also identified within this promoter region. The AL-P gene promoter fused to the β-glucuronidase (GUS) reporter gene has been examined for expression in transgenic alfalfa seedlings. Our findings have a potential application in plant genetic engineering; the AL-Pp may be used to drive the expression of heterologous genes in transgenic alfalfa plants.

Sesquiterpenes such as curcumol ( 1 ) and curdione ( 2 ) are the major ingredients of Rhizoma curcumae . Compounds ( 1 ) and ( 2 ) are isomers of one another and play important roles in Chinese Traditional Medicine. Microbial transformations of naturally occurring curcumol and curdione by Cunninghamella elegans AS 3.2028 were studied. In this research, stereoselective epoxidation at the double bond of curcumol led to 10 S ,14-epoxycurcumol ( 3 ) as the major metabolite, with no detectable 10 R ,14-epoxycurcumol ( 4 ). Epoxidation also occurred at the double bond of curdione, generating both (1 S ,10 S )- and (1 R ,10 R )-1,10-epoxycurdione ( 5 ) and ( 6 ). The diastereomeric excess ( de ) of the S diastereomer was 27%. The selectivity of the biotransformation is discussed.

Lmbr1 is regarded as a key gene that controls the digital model formation in early developmental stages of the chicken. However, there are few reports of lmbr1 expression levels and tendencies in 4-toe and 5-toe chicken species. Therefore, the objective of this study was to compare the lmbr1 expression in White Leghorn (4-toe) and Chinese Silky (5-toe). Firstly, total RNA was extracted from 14 different embryonic development stages (HH3 to HH31) in White Leghorn and Chinese Silky. Secondly, dramatic gene expression changes of lmbr1 were monitored by RT-PCR, which indicated a general up-down-up tendency with subtle differences between these two species. Moreover, Q-PCR reactions were performed to quantitate the expression level of lmbr1 in the 14 selected developmental stages. These data demonstrated a first lmbr1 expression peak of 18.68 and 15.32, a lmbr1 expression trough of 6.61 and 1.80, and a second lmbr1 expression peak of 22.33 and 12.48 in White Leghorn and Chinese Silky, respectively. Finally, embryonic in situ hybridization analysis identified that lmbr1 expressed in the ectoderm in HH21, HH23 and HH24 developmental stages in both species.

The aim of this study was to investigate the therapeutic effects of the combination of paeoniflorin and albiflorin (CPA) extracted from Paeonia radix on radiation and chemotherapy induced myelosuppression in two animal models: mice and rabbits. Mice were exposed to X-ray radiation (400 Roentgen), and both mice and rabbits were intraperitoneally injected with cyclophosphamide (100.0 mg/kg) and cytarabine chloride (92.7 mg/kg), respectively, for 3 days to induce myelosuppression. CPA was subsequently administrated intravenously at low (15.0 mg/kg for mice, 6.00 mg/kg for rabbits), intermediate (30.0 mg/kg for mice, 12.0 mg/kg for rabbits) and high (60.0 mg/kg for mice, 24.0 mg/kg for rabbits) doses, as well as orally (60.0 mg/kg for mice, 24.0 mg/kg for rabbits) for 7 days. Shenqi tablets were used as positive controls (oral administration of 936.0 mg/kg for mice, 336.0 mg/kg for rabbits). The administration of CPA significantly ameliorated myelosuppression in all cases. For the X-ray irradiated mice and the chemotherapy treated mice and rabbits, high dosages of CPA resulted in the recovery of, respectively, 94.4%, 95.3% and 97.7% of hemoglobin content; 67.7%, 92.0% and 94.3% of platelet numbers; 26.8%, 137.1% and 107.3% of white blood cell counts; as well as a reversal in the reduction of peripheral differential white blood cell counts. There was also a recovery of 50.9%, 146.1% and 92.3%, respectively, in the animals' relative spleen weight. Additionally, a recovery of 35.7% and 87.2% in the number of bone marrow nucleated cells was observed in the radio- and chemotherapy treated mice, respectively. Bone marrow white blood cell counts also resumed to normal levels. These results substantiate the marked therapeutic effects of CPA to ameliorate myelosuppression induced by radio and chemotherapy.