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51.
Somayeh Niknam Mohammad Ali Faramarzi Khosrou Abdi Mojtaba Tabatabaei Yazdi Mohsen Amini Hossein Rastegar 《World journal of microbiology & biotechnology》2010,26(1):119-123
Very limited studies have been done to investigate the algal biotransformation of codeine to its opioid derivatives. On the
other hand, microalgae have been recently introduced as potential tools for green synthesis of various organic compounds.
In the present work, the capability of biotransformation of codeine by a locally isolate strain of cyanobacterium, Nostoc muscorum, was evaluated. Incubation of the whole cells of Nostoc muscorum with codeine (I) under continuous light photoregime of 60 μmol photons/m2s at 25°C for 5 days gave rise to four transformation products. The bioproducts were separated by gas chromatography and identified
as 6-acetylcodeine (II), oxycodone (III), norcodeine (IV), morphine (V) and based on their mass spectra. Observed modifications included O-demethylation, N-demethylation, C6-acetylation, C14-hydroxilation,
Δ7-reduction, and C6-oxidation. The ability of N. muscorum to convert codeine to oxycodone (III) represents an uncommon pattern of codeine metabolism in microorganisms that may be of industrial importance. 相似文献
52.
Mohammad Ali Faramarzi Mojtaba Tabatabaei Yazdi Hadi Ghostinroudi Mohsen Amini Younes Ghasemi Hoda Jahandar Homeira Arabi 《Annals of microbiology》2006,56(3):253-256
Nostoc muscorum PTCC 1636 was examined for its ability to convert androst-4-en-3,17-dione (AD) and androst-1,4-dien-3,17-dione (ADD) to their 17-hydroxy related derivatives in BG-11 medium. Bioconversion procedures were carried out at 25 °C without shaking. The metabolites obtained were purified using chromatographic methods and characterized as testosterone and 1-dehydrotestosterone on the basis of their spectroscopic features. In both cases, the bioreaction characteristics observed were 17-carbonyl reduction. 相似文献
53.
54.
Yazdi Mojtaba Tabatabaei Khosravi Amir Abbas Nemati Mahboob Motlagh Niloofar Davoodi Vijeh 《World journal of microbiology & biotechnology》2003,19(1):79-84
Two intracellular -glucosidases (E.C. 3.2.1.21) were purified from the filamentous fungus Neurospora crassa, mutant cell-1 (FGSC no. 4335) and characterized. The extent of purification were 2.55- and 28.89-fold for -glucosidase A and -glucosidase B, respectively. -Glucosidase A was a dimeric protein, and B a monomeric protein, with molecular masses of 178 and 106 kDa, respectively. Both isoenzymes were glycoproteins with relatively high carbohydrate contents (-glucosidase A, 29.2%; -glucosidase B, 34.2%). The isoelectric points determined by IEF were 6.27 and 4.72, respectively. pH optima for activity were determined to be 5.0 and 5.5, and temperature optima to be 55 and 60 °C, for -glucosidases A and B, respectively. Both purified -glucosidases. especially -glucosidase B, showed relatively high stability against pH and temperature. Both enzymes were stable in the pH range of 5.0–9.0. The activities were completely retained up to 48 h at temperatures below 40 °C. At higher temperatures, enzymes were relatively unstable and lost their activities at 60 °C after 24 h. Both -glucosidases were highly activated by CuCl2, and inhibited by SnCl2 and KMnO4. Hg2+ and Ag+ also inhibited severely -glucosidase B. The K
m and V
max values of the isoenzymes against cellobiose as substrate were 1.50 mM and 12.2mol min–1 mg–1 for -glucosidase A and 2.76 mM and 143.5 mol min–1 mg–1 for -glucosidase B. 相似文献
55.
Yazdi MT Arabi H Faramarzi MA Ghasemi Y Amini M Shokravi S Mohseni FA 《Phytochemistry》2004,65(15):2205-2209
Hydrocortisone was converted in the culture of an isolated strain of the cyanobacterium Nostoc muscorum PTCC 1636 into some androstane and pregnane derivatives. The microorganism was, isolated during a screening program from soil samples collected from paddy fields of north of Iran. The bioproducts obtained were purified using chromatographic methods and identified as 11beta-hydroxytestosterone, 11beta-hydroxyandrost-4-en-3,17-dione and 11beta,17alpha,20beta,21-tetrahydroxypregn-4-en-3-one on the basis of their spectroscopic features. 相似文献
56.
Mina Aleemardani Atefeh Solouk Somaye Akbari Mohammad Moeini 《Biotechnology and bioengineering》2023,120(1):297-311
Supplying sufficient oxygen within the scaffolds is one of the essential hindrances in tissue engineering that can be resolved by oxygen-generating biomaterials (OGBs). Two main issues related to OGBs are controlling oxygenation and reactive oxygen species (ROS). To address these concerns, we developed a composite scaffold entailing three layers (hydrogel-electrospun fibers-hydrogel) with antioxidant and antibacterial properties. The fibers, the middle layer, reinforced the composite structure, enhancing the mechanical strength from 4.27 ± 0.15 to 8.27 ± 0.25 kPa; also, this layer is made of calcium peroxide and silk fibroin (SF) through electrospinning, which enables oxygen delivery. The first and third layers are physical SF hydrogels to control oxygen release, containing quercetin (Q), a nonenzymatic antioxidant. This composite scaffold resulted in almost more than 40 mmHg of oxygen release for at least 13 days, and compared with similar studies is in a high range. Here, Q was used for the first time for an OGB to scavenge the possible ROS. Q delivery not only led to antioxidant activity but also stabilized oxygen release and enhanced cell viability. Based on the given results, this composite scaffold can be introduced as a safe and controllable oxygen supplier, which is promising for tissue engineering applications, particularly for bone. 相似文献
57.
Fatemeh Roshani Hossien Delavar Kasmaee Kowsar Falahati Ghazaleh Arabzade Atefeh Sohan Forooshan Moghadam Mohammad Hossein Sanati 《Reports of Biochemistry & Molecular Biology》2021,10(3):396
Background:Etiology of multiple sclerosis is non-clarified. It seems that environmental factors impact epigenetic in this disease. Micro-RNAs (MIR) as epigenetic factors are one of the most important factors in non-genetically neurodegenerative diseases. It has been found MIR-144 plays a main role in the regulation of many processes in the central nervous system. Here, we aimed to investigation of MIR-144 expression alteration in Multiple sclerosis (MS) patients.Methods:In this study 32 healthy and 32 MS patient''s blood sample were analyzed by quantitative Real-Time PCR method and obtained data analyzed by REST 2009 software.Results:Analysis of Real-Time PCR data revealed that miR-144 Increase significantly in MS patients compared to healthy controls.Conclusion:The increase of MIR-144 expression in MS patients is obvious. MIR-144 can be used as a biomarker of MS and help to early diagnosis and treatment of this disease.Key Words: MicroRNA (miRNA), MiRNA-144, Multiple Sclerosis (MS) 相似文献
58.
Karchani Mohsen Kakooei Hossein Yazdi Zohre Zare Mohsen 《Sleep and biological rhythms》2011,9(2):95-102
Sleep and Biological Rhythms - Night work has many harmful effects on the health, efficiency and safety of workers. This study evaluates the effects of bright-light exposure (BL) on subjective... 相似文献
59.
60.
Ghasem Rahimi Kalateh Shah Mohammad Atefeh Ghahremanloo Arash Soltani Esmat Fathi Seyed Isaac Hashemy 《Journal of cellular physiology》2020,235(7-8):5449-5460
Immunotherapy has caused a paradigm shift in the treatment of several malignancies, particularly the blockade of programmed death-1 (PD-1) and its specific receptor/ligand PD-L1 that have revolutionized the treatment of a variety of malignancies, but significant durable responses only occur in a small percentage of patients, and other patients failed to respond to the treatment. Even those who initially respond can ultimately relapse despite maintenance treatment, there is considerable potential for synergistic combinations of immunotherapy and chemotherapy agents with immune checkpoint inhibitors into conventional cancer treatments. The clinical experience in the use of cytokines in the clinical setting indicated the efficiency of cytokine therapy in cancer immunotherapy. Combinational approaches to enhancing PD-L1/PD-1 pathways blockade efficacy with several cytokines such as interleukin (IL)-2, IL-15, IL-21, IL-12, IL-10, and interferon-α (IFN-α) may result in additional benefits. In this review, the current state of knowledge about PD-1/PD-L1 inhibitors, the date in the literature to ascertain the combination of anti-PD-1/PD-L1 antibodies with cytokines is discussed. Finally, it is noteworthy that novel therapeutic approaches based on the efficient combination of recombinant cytokines with the PD-L1/PD-1 blockade therapy can enhance antitumor immune responses against various malignancies. 相似文献