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11.
A new strain of the fungusMorchella nov. ES-1 (ATCC 20951) that produces blue pigment in submerged culture has been isolated. The blue pigment was extracted by chloroform or ethyl acetate treatment. The crude extract when chromatographed yielded three fractions; a blue one has been identified by mass spectrometry as indigotin. Fermentation studies using enriched media revealed that maximum accumulation of indigotin in culture was approx 24 mg/L in 168 h. 相似文献
12.
Tabassum Jannat Md. Jamal Hossain Ahmed M. El-Shehawi Md. Ruhul Kuddus Mohammad A. Rashid Sarah Albogami Ibrahim Jafri Mohamed El-Shazly Mohammad Rashedul Haque 《Molecules (Basel, Switzerland)》2022,27(13)
The aim of the study was to conduct phytochemical and pharmacological investigations of Wrightia coccinea (Roxb. ex Hornem.) Sims via several in vitro, in vivo, and in silico models. A total of four compounds were identified and isolated from the methanol extract of the bark and the methanol extract of the seed pulp of W. coccinea through successive chromatographic techniques and were characterized as 3β-acetyloxy-olean-12-en-28-ol (1), wrightiadione (2), 22β-hydroxylupeol (3), and β-sitosterol (4) by spectroscopic analysis. The aqueous fraction of the bark and chloroform fraction of the fruits provided the most potent antioxidant capacity (IC50 = 7.22 and 4.5 µg/mL, respectively) in DPPH free radical scavenging assay compared with the standard ascorbic acid (IC50 = 17.45 µg/mL). The methanol bark extract and the methanol fruit coat extract exerted anti-diarrheal activity by inhibiting 74.55 ± 0.67% and 77.78 ± 1.5% (mean ± SEM) of the diarrheal episode in mice, respectively, after four hours of loading the samples. In the hypoglycemic test, the methanol bark extract and the methanol fruit coat extract (400 mg/kg) produced a significant (p < 0.05) reduction in the blood glucose level in mice. Both doses of the plant extracts (200 mg/kg and 400 mg/kg) used in the study induced a significant (p < 0.05) increase in pain reaction time. The in vitro and in vivo findings were supported by the computational studies. The isolated compounds exhibited higher binding affinity compared with the standard drugs towards the active binding sites of glutathione reductase, epidermal growth factor receptor (EGFR), kappa opioid receptor, glucose transporter 3 (GLUT 3), Mu opioid receptor, and cyclooxygenase 2 (COX-2) proteins due to their potent antioxidant, cytotoxic, anti-diarrheal, hypoglycemic, and central and peripheral analgesic properties, respectively. The current findings concluded that W. coccinea might be a potential natural source for managing oxidative stress, diarrhea, hyperglycemia, and pain. Further studies are warranted for extensively phytochemical screening and establishing exact mechanisms of action. 相似文献
13.
Mufarreh Asmari Muhammad Waqas Adel Ehab Ibrahim Sobia Ahsan Halim Ajmal Khan Ahmed Al-Harrasi Hermann Wtzig Sami El Deeb 《Molecules (Basel, Switzerland)》2022,27(14)
The microscale thermophoresis (MST) technique was utilized to investigate lactoferrin–drug interaction with the iron chelator, deferiprone, using label-free system. MST depends on the intrinsic fluorescence of one interacting partner. The results indicated a significant interaction between lactoferrin and deferiprone. The estimated binding constant for the lactoferrin–deferiprone interaction was 8.9 × 10−6 ± 1.6, SD, which is to be reported for the first time. Such significant binding between lactoferrin and deferiprone may indicate the potentiation of the drug secretion into a lactating mother’s milk. The technique showed a fast and simple approach to study protein–drug interaction while avoiding complicated labeling procedures. Moreover, the binding behavior of deferiprone within the binding sites of lactoferrin was investigated through molecular docking which reflected that deferiprone mediates strong hydrogen bonding with ARG121 and ASP297 in pocket 1 and forms H-bond and ionic interaction with ASN640 and ASP395, respectively, in pocket 2 of lactoferrin. Meanwhile, iron ions provide ionic interaction with deferiprone in both of the pockets. The molecular dynamic simulation further confirmed that the binding of deferiprone with lactoferrin brings conformational changes in lactoferrin that is more energetically stable. It also confirmed that deferiprone causes positive correlation motion in the interacting residues of both pockets, with strong negative correlation motion in the loop regions, and thus changes the dynamics of lactoferrin. The MM-GBSA based binding free energy calculation revealed that deferiprone exhibits ∆G TOTAL of −63,163 kcal/mol in pocket 1 and −63,073 kcal/mol in pocket 2 with complex receptor–ligand difference in pocket 1 and pocket 2 of −117.38 kcal/mol and −111.54 kcal/mol, respectively, which in turn suggests that deferiprone binds more strongly in the pocket 1. The free energy landscape of the lactoferrin–deferiprone complex also showed that this complex remains in a high energy state that confirms the strong binding of deferiprone with the lactoferrin. The current research concluded that iron-chelating drugs (deferiprone) can be transported from the mother to the infant in the milk because of the strong attachment with the lactoferrin active pockets. 相似文献
14.
15.
Shofiul Azam Md. Ezazul Haque Duk-Yeon Cho Joon-Soo Kim Md. Jakaria In-Su Kim Dong-Kug Choi 《Molecules (Basel, Switzerland)》2022,27(9)
Autophagy is a cellular homeostatic process by which cells degrade and recycle their malfunctioned contents, and impairment in this process could lead to Parkinson’s disease (PD) pathogenesis. Dioscin, a steroidal saponin, has induced autophagy in several cell lines and animal models. The role of dioscin-mediated autophagy in PD remains to be investigated. Therefore, this study aims to investigate the hypothesis that dioscin-regulated autophagy and autophagy-related (ATG) proteins could protect neuronal cells in PD via reducing apoptosis and enhancing neurogenesis. In this study, the 1-methyl-4-phenylpyridinium ion (MPP+) was used to induce neurotoxicity and impair autophagic flux in a human neuroblastoma cell line (SH-SY5Y). The result showed that dioscin pre-treatment counters MPP+-mediated autophagic flux impairment and alleviates MPP+-induced apoptosis by downregulating activated caspase-3 and BCL2 associated X, apoptosis regulator (Bax) expression while increasing B-cell lymphoma 2 (Bcl-2) expression. In addition, dioscin pre-treatment was found to increase neurotrophic factors and tyrosine hydroxylase expression, suggesting that dioscin could ameliorate MPP+-induced degeneration in dopaminergic neurons and benefit the PD model. To conclude, we showed dioscin’s neuroprotective activity in neuronal SH-SY5Y cells might be partly related to its autophagy induction and suppression of the mitochondrial apoptosis pathway. 相似文献
16.
Lee Chuin Chen Md. Matiur Rahman Kenzo Hiraoka 《Journal of mass spectrometry : JMS》2012,47(8):1083-1089
Standard field desorption (FD) ionization is implemented under high vacuum condition. In this paper, non‐vacuum FD is performed under a super‐atmospheric pressure environment using untreated tungsten wires as FD emitter, and the ion source was coupled to a commercial linear ion trap mass spectrometer. The operating pressure of the ion source was 6 bars which was high enough to provide sufficient dielectric strength to the working gas so that the high voltage that was required for FD could be applied to the emitter without occurrence of electrical discharge. Non‐volatile sample deposited on the bare tungsten wire FD emitter was heated by flowing direct current through the emitter. Similar to vacuum FD, the formation of conical protrusion of the liquefied sample layer under the strong electric field was also observed. Using the present ion source, high pressure field‐desorption of polar neutral compounds, organic salts and ionic liquids is demonstrated. Copyright © 2012 John Wiley & Sons, Ltd. 相似文献
17.
Dr. Matthieu Autillo Md. Ashraful Islam Julie Héron Laetitia Guérin Dr. Eleonor Acher Dr. Christelle Tamain Dr. Marie-Claire Illy Dr. Philippe Moisy Dr. Eric Colineau Dr. Jean-Christophe Griveau Dr. Claude Berthon Dr. Hélène Bolvin 《Chemistry (Weinheim an der Bergstrasse, Germany)》2021,27(24):7138-7153
Actinide +VI complexes ( = , and ) with dipicolinic acid derivatives were synthesized and characterized by powder XRD, SQUID magnetometry and NMR spectroscopy. In addition, and complexes were described by first principles CAS based and two-component spin-restricted DFT methods. The analysis of the 1H paramagnetic NMR chemical shifts for all protons of the ligands according to the X-rays structures shows that the Fermi contact contribution is negligible in agreement with spin density determined by unrestricted DFT. The magnetic susceptibility tensor is determined by combining SQUID, pNMR shifts and Evans’ method. The SO-RASPT2 results fit well the experimental magnetic susceptibility and pNMR chemical shifts. The role of the counterions in the solid phase is pointed out; their presence impacts the magnetic properties of the complex. The temperature dependence of the pNMR chemical shifts has a strong contribution, contrarily to Bleaney's theory for lanthanide complexes. The fitting of the temperature dependence of the pNMR chemical shifts and SQUID magnetic susceptibility by a two-Kramers-doublet model for the complex and a non-Kramers-doublet model for the complex allows for the experimental evaluation of energy gaps and magnetic moments of the paramagnetic center. 相似文献
18.
19.
Various types of trimethylsilyl and tert-butyldimethylsilyl ethers of primary and secondary benzylic alcohols could be selectively converted to their corresponding carbonyl compounds with MnO2 in the presence of AlCl3 in good to excellent yields. 相似文献
20.
Sanjoy Pal Trinath Chowdhury Kishalay Paria Sounik Manna Sana Parveen Manjeet Singh Pralay Sharma Sk Saruk Islam Sk Md Abu Imam Saadi Santi M. Mandal 《印度化学会志》2022,99(1):100244
BackgroundThe recent pandemic by COVID-19 is a global threat to human health. The disease is caused by SARS-CoV-2 and the infection rate is increased more quickly than MERS and SARS as their rapid adaptation to varied climatic conditions through rapid mutations. It becomes more severe due to the lack of proper therapeutic drugs, insufficient diagnostic tool, scarcity of appropriate drug, life supporting medical facility and mostly lack of awareness. Therefore, preventive measure is one of the important strategies to control. In this context, herbal medicinal plants received a noticeable attention to treat COVID-19 in Indian subcontinent. Here, 44 Indian traditional plants have been discussed with their novel phytochemicals that prevent the novel corona virus. The basic of SARS-CoV-2, their common way of transmission including their effect on immune and nervous system have been discussed. We have analysed their mechanism of action against COVID-19 following in-silico analysis. Their probable mechanism and therapeutic approaches behind the activity of phytochemicals to stimulate immune response as well as inhibition of viral multiplication discussed rationally. Thus, mixtures of active secondary metabolites/phytochemicals are the only choice to prevent the disease in countries where vaccination will take long time due to overcrowded population density. 相似文献