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Records with Subject: Biosystems
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Effects of Alginate and Chitosan on Activated Carbon as Immobilisation Beads in Biohydrogen Production
Nur Farahana Dzul Rashidi, Nur Syakina Jamali, Siti Syazwani Mahamad, Mohamad Faizal Ibrahim, Norhafizah Abdullah, Siti Fatimah Ismail, Shamsul Izhar Siajam
April 27, 2021 (v1)
Subject: Biosystems
Keywords: activated carbon, alginate, biohydrogen production, chitosan, entrapment, immobilised cells
In this study, the effects of alginate and chitosan as entrapped materials in the biofilm formation of microbial attachment on activated carbon was determined for biohydrogen production. Five different batch fermentations, consisting of mixed concentration alginate (Alg), were carried out in a bioreactor at temperature of 60 °C and pH 6.0, using granular activated carbon (GAC) as a primer for cell attachment and colonisation. It was found that the highest hydrogen production rate (HPR) of the GAC−Alg beads was 2.47 ± 0.47 mmol H2/l.h, and the H2 yield of 2.09 ± 0.22 mol H2/mol sugar was obtained at the ratio of 2 g/L of Alg concentration. Next, the effect of chitosan (C) as an external polymer layer of the GAC−Alg beads was investigated as an alternative approach to protecting the microbial population in the biofilm in a robust environment. The formation of GAC with Alg and chitosan (GAC−AlgC) beads gave the highest HPR of 0.93 ± 0.05 mmol H2/l.h, and H2 yield of 1.11 ± 0.35 mol H2/mol... [more]
Recent Development of Microfluidic Technology for Cell Trapping in Single Cell Analysis: A Review
Yilin Deng, Ying Guo, Bin Xu
April 27, 2021 (v1)
Subject: Biosystems
Keywords: cell trapping, microfluidic, review, single cell analysis
Microfluidic technology has emerged from the MEMS (Micro-Electro-Mechanical System)-technology as an important research field. During the last decade, various microfluidic technologies have been developed to open up a new era for biological studies. To understand the function of single cells, it is very important to monitor the dynamic behavior of a single cell in a living environment. Cell trapping in single cell analysis is urgently demanded There have been some review papers focusing on drug screen and cell analysis. However, cell trapping in single cell analysis has rarely been covered in the previous reviews. The present paper focuses on recent developments of cell trapping and highlights the mechanisms, governing equations and key parameters affecting the cell trapping efficiency by contact-based and contactless approach. The applications of the cell trapping method are discussed according to their basic research areas, such as biology and tissue engineering. Finally, the paper h... [more]
Assessment of the Release Profile of Fibroblast Growth Factor-2-Load Mesoporous Calcium Silicate/Poly-ε-caprolactone 3D Scaffold for Regulate Bone Regeneration
Chia-Tze Kao, Yen-Jen Chen, Tsui-Hsien Huang, Yen-Hong Lin, Tuan-Ti Hsu, Chia-Che Ho
April 27, 2021 (v1)
Subject: Biosystems
Keywords: 3D printing, bone tissue engineering, drug delivery, fibroblast growth factor-2, mesoporous calcium silicate nanoparticle
Recent advances in three-dimensional printing technology enable facile and on-demand fabrication of patient-specific bone scaffolds. However, there is still an urgent need for printable biomaterials with osteoinductivity. In the present study, we propose an approach to synthesize fibroblast growth factor-2 loaded-mesoporous calcium silicate nanoparticles. The growth factor loaded-nanoparticles served as fillers of polycaprolactone and then the composite scaffolds with a controlled pore structure were obtained through a fused deposition modeling technique. To evaluate the feasibility of the composite scaffolds in bone tissue engineering, drug release kinetic, bioactivity, cell proliferation, differentiation, and animal study were conducted. Our findings illustrate that utilization of mesoporous calcium silicate allowed the introduction of fibroblast growth factor-2 into the composite scaffolds through a simple soaking process and then gradually released from the scaffold to facilitate p... [more]
Mutational Analysis of the Binding of Alternative Substrates and Inhibitors to the Active Site of Human Glutathione Transferase P1−1
Abeer Shokeer, Aram Ismail, Usama M. Hegazy, Rüdiger H. Kolm, Bengt Mannervik
April 27, 2021 (v1)
Subject: Biosystems
Keywords: alternative thiol substrates, Glutathione transferase P1–1, inhibitor binding energy, Telcyta, Telintra
Glutathione transferases (GSTs) are enzymes that play a critical role in cellular detoxication by catalyzing the nucleophilic attack of glutathione on the electrophilic center of a number of xenobiotic compounds, including many therapeutic drugs. Mutations of amino acid residues in the glutathione-binding site of human glutathione transferase P1−1, namely W39C, K45A, Q52A, Q52K, and Q52E, have been engineered. The recombinant mutant proteins were expressed in Escherichia coli, but only mutants K45A, Q52A, and Q52K showed measurable activity. Steady-state kinetics comparing glutathione with the alternative thiol substrate γ-glutamylcysteine demonstrated the importance of the glycine residue in glutathione for high catalytic efficiency. Inhibition experiments with a set of glutathione analogs structurally related to the therapeutic drugs Telintra and Telcyta enabled determination of binding energies that were contributed by different substituents. The effects of substituting amino acid s... [more]
A New Computational Approach to Evaluating Systemic Gene−Gene Interactions in a Pathway Affected by Drug LY294002
Shinuk Kim
April 27, 2021 (v1)
Subject: Biosystems
Keywords: drug-induced gene networks, inverse problem, systemic gene networks
In this study, we investigate how drugs systemically affect genes via pathways by integrating information from interactions between chemical compounds and molecular expression datasets, and from pathway information such as gene sets using mathematical models. First, we adopt drug-induced gene expression datasets; then, employ gene set enrichment analysis tools for selecting candidate enrichment pathways; and lastly, implement the inverse algorithm package for identifying gene−gene regulatory networks in a pathway. We tested LY294002-induced datasets of the MCF7 breast cancer cell lines, and found a CELL CYCLE pathway with 101 genes, ERBB signaling pathway consisting of 82 genes, and MTOR pathway consisting of 45 genes. We consider two interactions: quantity strength depending on number of interactions, and quality strength depending on weight of interaction as positive (+) and negative (−) interactions. Our methods revealed ANAPC1-CDK6 (−0.412) and ORC2L- CHEK1(0.951) for the CELL CYCL... [more]
Design and Characterization of a Fluidic Device for the Evaluation of SIS-Based Vascular Grafts
Alejandra Riveros, Monica Cuellar, Paolo F. Sánchez, Carolina Muñoz-Camargo, Juan C. Cruz, Néstor Sandoval, Omar D. Lopez Mejia, Juan C. Briceño
April 16, 2021 (v1)
Subject: Biosystems
Keywords: computational fluid dynamics (CFD), fluidic system, human umbilical vein endothelial cells (HUVEC) growth, porcine intestinal submucosa (SIS), vascular graft
Currently available small diameter vascular conduits present several long-term limitations, which has prevented their full clinical implementation. Commercially available vascular grafts show no regenerative capabilities and eventually require surgical replacement; therefore, it is of great interest to develop alternative regenerative vascular grafts (RVG). Decellularized Small Intestinal Submucosa (SIS) is an attractive material for RVG, however, the evaluation of the performance of these grafts is challenging due to the absence of devices that mimic the conditions found in vivo. Thereby, the objective of this study is to design, manufacture and validate in silico and in vitro, a novel fluidic system for the evaluation of human umbilical vein endothelial cells (HUVECs) proliferation on SIS-based RVG under dynamical conditions. Our perfusion and rotational fluidic system was designed in Autodesk Inventor 2018. In silico Computational Fluid Dynamics (CFD) validation of the system was ca... [more]
Curation and Analysis of a Saccharomyces cerevisiae Genome-Scale Metabolic Model for Predicting Production of Sensory Impact Molecules under Enological Conditions
William T. Scott Jr, Eddy J. Smid, Richard A. Notebaart, David E. Block
April 16, 2021 (v1)
Subject: Biosystems
Keywords: aroma, flux balance analysis (FBA), genome-scale metabolic models, Saccharomyces cerevisiae, wine fermentation
One approach for elucidating strain-to-strain metabolic differences is the use of genome-scale metabolic models (GSMMs). To date GSMMs have not focused on the industrially important area of flavor production and, as such; do not cover all the pathways relevant to flavor formation in yeast. Moreover, current models for Saccharomyces cerevisiae generally focus on carbon-limited and/or aerobic systems, which is not pertinent to enological conditions. Here, we curate a GSMM (iWS902) to expand on the existing Ehrlich pathway and ester formation pathways central to aroma formation in industrial winemaking, in addition to the existing sulfur metabolism and medium-chain fatty acid (MCFA) pathways that also contribute to production of sensory impact molecules. After validating the model using experimental data, we predict key differences in metabolism for a strain (EC 1118) in two distinct growth conditions, including differences for aroma impact molecules such as acetic acid, tryptophol, and h... [more]
Analysis and Anticancer Effects of Active Compounds from Spatholobi Caulis in Human Breast Cancer Cells
Hung Manh Phung, Hesol Lee, Sullim Lee, Dongyeop Jang, Chang-Eop Kim, Ki Sung Kang, Chang-Seob Seo, You-Kyung Choi
April 16, 2021 (v1)
Subject: Biosystems
Keywords: apoptosis, breast cancer, gallic acid, MCF-7, network pharmacology, p53, Spatholobi Caulis
Breast cancer is the most common malignancy in both developing and developed countries. In this study, we simultaneously analyzed nine constituent compounds from Spatholobi Caulis (gallic acid, (−)-gallocatechin, 3,4-dihydroxybenzoic acid, procyanidin B1, 3,4-dihydroxybenzaldehyde, catechin, procyanidin B2, epicatechin, and (−)-epicatechin gallate) and examined their anticancer effects on MCF-7 and MDA-MB-231 human breast cancer cells. The experimental results indicated that the gallic acid showed the strongest cytotoxic effect on MCF-7 cells among tested compounds whilst most of samples did not express inhibitory effect on viability of MDA-MB-231 cells, except for 70% ethanol extract of S. Caulis. Thus, gallic acid was chosen to extend anticancer mechanism study on MCF-7 cells. Our data showed that the gallic acid induced apoptotic MCF-7 cell death through both extrinsic and intrinsic pathways, which increased the expression of cleaved caspase-7, -8, and -9, Bax and p53, but reduced t... [more]
Inhibitory Effects of Thymol Isolated from Curcuma longa L. on Adipogenesis in HepG2 Cells
Dam-Hee Kang, Young-Seob Lee, Seon Min Oh, Dahye Yoon, Doo Jin Choi, Dong-Yeul Kwon, Ok-Hwa Kang, Dae Young Lee
April 16, 2021 (v1)
Subject: Biosystems
Keywords: Curcuma longa L., hepatoprotective effect, HepG2, NAFLD, quantification, thymol
Non-alcoholic fatty liver disease (NAFLD) is a disease associated with metabolic syndromes such as diabetes and obesity, regardless of alcohol consumption, and refers to the accumulation of triacylglycerols in the liver. Thymol (THY) is a vegetable essential oil that is naturally contained in the Zingiberaceae and Lamiaceae families. THY was isolated from Curcuma longa L. The rhizomes of Curcuma longa L. were dried, sliced and extracted with 50% ethanol and then isolated through repeated column chromatography. This study was conducted to investigate the inhibitory effect of THY, even in non-alcoholic fatty liver disease, in relation to the inhibiting hyperlipidemia effect of THY, which was demonstrated in previous studies. Hepatocytes were treated with oleate (OA) containing THY to observe lipid accumulation by Oil Red O staining (ORO). We also tested the effect of THY on triacylglycerols (TG) and total cholesterol (TC) in HepG2 cells. Western blot and real-time RT-PCR using sterol reg... [more]
Antibacterial Activity of Chitosan Nanoparticles: A Review
Murugesan Chandrasekaran, Ki Deok Kim, Se Chul Chun
April 16, 2021 (v1)
Subject: Biosystems
Keywords: antibacterial activity, bacteria, chitosan, chitosan nanoparticles, gram negative bacteria, gram positive bacteria
In recent years, nanotechnology has attracted attention in many fields because it has several up-and-coming novel uses. Many researchers have suggested that chitosan nanoparticles (CS-NPs) and their derivatives are one of the best nanomaterials for delivering antibacterial activity. CS-NPs have a broad spectrum of antibacterial activity, but they manifest different inhibitory efficacy against gram-negative (G−) and gram-positive (G+) bacterial species. The mechanism of antibacterial action is an intricate process that varies between G− and G+ bacteria as a result of the differences in cell wall and cell membrane chemistry. In previous studies, greater antibacterial activity was more evident against G− bacteria than G+ bacteria, whereas in some studies G+ bacteria were more sensitive. Researchers predicted that the varied responses of bacteria are caused by the mixed hydrophilicity and negative charge distribution on the bacterial surface. Moreover, its activity depends on a number of v... [more]
Socheongryongtang Modulates Asthma-Related Changes via Modulation of TNF-α and T-bet as well as IFN-γ in an Asthma Murine Model
So-Hyeon Bok, Seung Sik Cho, Chun-Sik Bae, Bossng Kang, Hong-Seok Son, Dae-Hun Park
April 16, 2021 (v1)
Subject: Biosystems
Keywords: asthma, IFN-γ, socheongryongtang, T-bet, TNF-α
In 2017 the World Health Organization (WHO) reported that 235 million people suffered from asthma, and that 383,000 deaths were due to asthma in 2015. Asthma cannot be completely eradicated and the medications for asthma are associated with many adverse effects. Socheongryongtang is one of the prescriptions which has traditionally been used for the treatment of pulmonary disease, but the anti-asthmatic mechanism is unclear. To investigate the anti-asthmatic mechanism of socheongryongtang, BALB/c mice were divided into five groups: control, asthma-induced control, dexamethasone treatment, and 150 mg/kg or 1500 mg/kg socheongryongtang treatment and several biomarkers were analyzed, such as white blood cell (WBC) and differential counts in broncheoalveolar fluid (BALF), immunoglobulin E (IgE) in serum, and morphological changes/helper T cell-related cytokines/transcription factor in the lung. The therapeutic ingredients were also analyzed. Socheongryongtang inhibited the neutrophils diffe... [more]
Review of Natural Compounds for the Management and Prevention of Lymphoma
Yongmin Cho, Moon Nyeo Park, Seungjin Noh, Seog Young Kang, Bonglee Kim
April 16, 2021 (v1)
Subject: Biosystems
Keywords: apoptosis, cancer system biology, cell cycle arrest, lymphoma, natural products
Lymphoma is a type of blood cancer that can be categorized into two types-Hodgkin lymphoma (HL) and Non-Hodgkin lymphoma (NHL). A total of 509,590 and 79,990 cases of NHL and HL were newly diagnosed in 2018, respectively. Although conventional therapy has stridden forward over recent decades, its adverse effects are still a hurdle to be solved. Thus, to help researchers develop better lymphoma treatment, this study aims to review the systematic anticancer data for natural products and their compounds. A variety of natural products showed anticancerous effects on lymphoma by regulation of intracellular mechanisms including apoptosis as well as cell cycle arrest. As these results shed light on the potential to substitute conventional therapy with natural products, it may become a promising strategy for lymphoma treatment in the near future.
Discovering Low Toxicity Ionic Liquids for Saccharomyces cerevisiae by Using the Agar Well Diffusion Test
Fatiha Missoun, Antonia Pérez de los Ríos, Víctor Ortiz-Martínez, María José Salar-García, Jesús Hernández-Fernández, Francisco José Hernández-Fernández
April 16, 2021 (v1)
Subject: Biosystems
Keywords: agar well diffusion test, biocompatibility, ionic liquids, Saccharomyces cerevisiae, toxicity
Ionic liquids (ILs) are new solvents widely used in many technologies due to their unique and advantageous physicochemical properties. In biotechnological applications, ILs can be used along with microorganisms such as Saccharomyces cerevisiae. Due to the enormous number of ILs that can be synthesized through the combination of different anions and cations, it is necessary to have an easy and quick tool for the preliminary screening of their biocompatibility for being used in biotechnological applications. In this work, the agar well diffusion test was successfully applied as a rapid method to identify toxic/nontoxic ILs toward S. cerevisiae. Sixty-three ILs containing a diverse set of cations and anions were used. Through this methodology, nine fully biocompatible ILs toward S. cerevisiae were identified, including: [Bmim+] [NO3−], [HOPmim+] [NO3−], [Bmim+] [NTf2−], [N8,8,8,1+] [NTf2−], [S2,2,2+] [NTf2−], [EMPyr+] [NTf2−], [BMPi+] [NTf2−], [Moxa+] [MeSO4−] and [Chol+] [H2PO4−]. The an... [more]
Functionalized N-Pyridinylmethyl Engrafted Bisarylmethylidenepyridinones as Anticancer Agents
Dhaifallah M. Al-thamili, Abdulrahman I. Almansour, Natarajan Arumugam, Faruq Mohammad, Raju Suresh Kumar
March 24, 2021 (v1)
Subject: Biosystems
Keywords: anticancer studies, apoptosis, caspase-3, functionalized unsaturated ketones, ROS generation
Structurally interesting N-pyridinylmethyl engrafted bisarylmethylidenepyridinones with high functionality have been constructed in good yield. The structural interpretation of these compounds has been done with the aid of spectroscopic analysis and further established by single crystal X-ray diffraction studies. Following physical characterization, the synthesized compounds were tested for their in vitro anticancer activity against HepG2 cancer cells and it was found that all of the compounds exhibited some level of activity. We observed a significant level of cell viability losses to the cancer cells, while only smaller losses to the non-cancer cells were observed. Besides, the mechanistic investigation of toxicology revealed that the cancer cells were undergoing apoptotic pathway, induced by the generation of oxidative stress and the involvement of caspases. The analysis provides preliminary evidence for the successful control of cancer cells with a minimal effect on healthy normal... [more]
Affinity of Fluoroquinolone−Safirinium Dye Hybrids to Phospholipids Estimated by IAM-HPLC
Krzesimir Ciura, Joanna Fedorowicz, Hanna Kapica, Alicja Adamkowska, Wiesław Sawicki, Jarosław Sączewski
March 24, 2021 (v1)
Subject: Biosystems
Keywords: fluoroquinolone–Safirinium dye hybrids, fluoroquinolones, immobilized artificial membrane
Nowadays, fluoroquinolones (FQs) constitute one of the most important classes of antibiotics. FQs are used to treat infections caused by Gram-positive and Gram-negative species. A set of fluoroquinolone−Safirinium dye hybrids has been synthesized in our laboratory as potential new dual-action antibacterial agents. In the present study we have evaluated how such a modification influences the affinity of FQs to phospholipids. The immobilized artificial membrane (IAM) high-performance liquid chromatography (IAM-HPLC) was used as a tool for the determination of phospholipids partitioning. The obtained results indicate that the fluoroquinolone−Safirinium dye hybrids, especially the SafiriniumP conjugates, display significantly lower affinity to phospholipids than the parent FQs. Despite the fact that the hybrid structures comprise a quaternary nitrogen atom and hence are permanently charged, the attractive electrostatic interactions between the solutes and negatively charged phospholipids d... [more]
Coal-Degrading Bacteria Display Characteristics Typical of Plant Growth Promoting Rhizobacteria
Yinka Titilawo, Wiya L. Masudi, Jacob T. Olawale, Lerato M. Sekhohola-Dlamini, A. Keith Cowan
March 14, 2021 (v1)
Subject: Biosystems
Keywords: biodegradation, coal discard, diesel-contaminated soil, discard dumps, phylogeny, plant growth-promoting bacteria
Coal mining produces large quantities of discard that is stockpiled in large dumps. This stockpiled material, termed coal discard, poses an environmental threat emphasising the need for appropriate bioremediation. Here, metagenomic analysis of the 16S rRNA from ten coal-degrading strains previously isolated from coal slurry from discard dumps and from the rhizosphere of diesel-contaminated sites was used to establish genetic relatedness to known plant growth-promoting (PGP) bacteria in the NCBI database. Measurement of indole and ammonium production and solubilisation of P and K were used to screen bacteria for PGP characteristics. BLAST analysis revealed ≥ 99% homology of six isolates with reference PGP strains of Bacillus, Escherichia, Citrobacter, Serratia, Exiguobacterium and Microbacterium, while two strains showed 94% and 91% homology with Proteus. The most competent PGP strains were Proteus strain ECCN 20b, Proteus strain ECCN 23b and Serratia strain ECCN 24b isolated from diese... [more]
Development, Characterization and In Vitro Evaluation of Paclitaxel and Anastrozole Co-Loaded Liposome
Minh Thanh Vu, Dinh Tien Dung Nguyen, Ngoc Hoi Nguyen, Van Thu Le, The Nam Dao, Thi Huong Nguyen, Tien Dung Cong, Truc Le-Buu Pham, Tri Duc Lam, Ngoc Thuy Trang Le
March 14, 2021 (v1)
Subject: Biosystems
Keywords: anastrozole, co-loaded, drug delivery system, paclitaxel, soy lecithin liposome
Paclitaxel (PTX) and anastrozole (ANA) have been frequently applied in breast cancer treatment. PTX is well-known for its anti-proliferative effect meanwhile ANA has just been discovered to act as an estrogen receptor α (ERα) ligand. The combination therapy of PTX and ANA is expected to improve treating efficiency, as ANA would act as a ligand binding with the ERα gene expressed in breast cancer cells and thereafter PTX would inhibit the division and cause death to those cancer cells. In this study, liposome-based nanocarriers (LP) were developed for co-encapsulation of PTX and ANA to improve the efficacy of the combined drugs in an Estrogen receptor-responsive breast cancer study. PTX-ANA co-loaded LP was prepared using thin lipid film hydration method and was characterized for morphology, size, zeta potential, drug encapsulation and in vitro drug release. In addition, cell proliferation (WST assay) and IN Cell Analyzer were used for in vitro cytotoxicity studies on a human breast can... [more]
Single and Binary Equilibrium Studies for Ni2+ and Zn2+ Biosorption onto Lemna gibba from Aqueous Solutions
Liliana Morales-Barrera, César Mateo Flores-Ortiz, Eliseo Cristiani-Urbina
February 22, 2021 (v1)
Subject: Biosystems
Keywords: competitive biosorption, divalent nickel, divalent zinc, Lemna gibba, pH and metal concentration effect, single and binary metal biosorption isotherm
The biosorption ability of Lemna gibba for removing Ni2+ and Zn2+ ions in aqueous batch systems, both individually and simultaneously, was examined. The influences of solution pH and initial single and binary metal concentrations on equilibrium Ni2+ and Zn2+ biosorption was explored. The optimal solution pH for Ni2+ and Zn2+ biosorption was 6.0, for both the single and binary metal systems. Ni2+ and Zn2+ biosorption capacities increased with increasing initial metal concentrations. The presence of Zn2+ ions more adversely affected the biosorption of Ni2+ ions in the binary metal systems than vice versa. The single and binary biosorption isotherms of Ni2+ and Zn2+ revealed that L. gibba’s affinity for Zn2+ ions was higher than that for Ni2+ ions. The Redlich−Peterson and Freundlich isotherm models fit well to the experimental equilibrium data of Ni2+ ions, whereas Redlich−Peterson and Langmuir models better described the equilibrium data of Zn2+ ions in single metal systems. The modifie... [more]
Effect of Heat Treatment and Light Exposure on the Antioxidant Activity of Flavonoids
Irina Ioannou, Leila Chekir, Mohamed Ghoul
February 22, 2021 (v1)
Subject: Biosystems
Keywords: bioactivities, degradation products, flavonoids, heat process, light exposure, TEAC
The application of food processes can lead to a modification of both the structure and the activities of flavonoids. In this article, the effect of heat treatment and exposure to light on the antioxidant activity of 6 model flavonoid solutions (rutin, naringin, eriodictyol, mesquitol, luteolin, and luteolin 7-O-glucoside) was studied. The evolution of the antioxidant activity measured after heat treatment of 130 °C at 2 h and an exposure to visible light for 2 weeks is measured by the ABTS (2,2′-Azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) diammonium salt) method and represented by a new parameter called ΔTEAC. The model solution of Mesquitol showed the highest increase in ΔTEAC after a heat treatment, a value of 200 mM was obtained. The increase in ΔTEAC is always greater with thermal treatment than with light exposure. Thus, temperature and light lead to different degradation pathways of the flavonoid. In vivo measurements were carried out with solutions of naringin, erodictyol,... [more]
Propagation and Molecular Characterization of Fowl Adenovirus Serotype 8b Isolates in Chicken Embryo Liver Cells Adapted on Cytodex™ 1 Microcarrier Using Stirred Tank Bioreactor
Chidozie C. Ugwu, Mohd Hair-Bejo, Mat I. Nurulfiza, Abdul R. Omar, Aini Ideris
February 22, 2021 (v1)
Subject: Biosystems
Keywords: bioreactor, chicken liver cell, Cytodex 1™ microcarrier, fowl adenovirus 8b, PCR
Large volume production of vaccine virus is essential for prevention and control of viral diseases. The objectives of this study were to propagate Fowl adenovirus (FAdV) isolate (UPM08136) in chicken embryo liver (CEL) cells adapted to Cytodex™ 1 microcarriers using stirred tank bioreactor (STB) and molecularly characterize the virus. CEL cells were prepared and seeded onto prepared Cytodex™ 1 microcarriers and incubated first in stationary phase for 3 h and in STB at 37 °C, 5% CO2, and 20 rpm for 24 h. The CEL cells were infected with FAdV isolate (UPM08136) passage 5 (UPM08136CELP5) or passage 20 (UPM08136CELP20) and monitored until cell detachment. Immunofluorescence, TCID50, sequencing, alignment of hexon and fiber genes, and phylogenetic analysis were carried out. CEL cells were adapted well to Cytodex™ 1 microcarriers and successfully propagated the FAdV isolates in STB with virus titer of 107.5 (UPM08136CELP5B1) and 106.5 (UPM08136CELP20B1) TCID50/mL. These isolates clustered wi... [more]
Diospyrin Modulates Inflammation in Poly I:C-Induced Macrophages via ER Stress-Induced Calcium-CHOP Pathway
Hyun-Ju Kim, Inamullah Khan, Adnan Shahidullah, Syed Muhammad Ashhad Halimi, Abdur Rauf, Ji-Young Lee, Young-Jin Kim, Bong-Youn Kim, Wansu Park
February 22, 2021 (v1)
Subject: Biosystems
Keywords: calcium, CHOP, cytokine, diospyrin, ER stress, ERK1/2, p38 MAPK, poly I:C, STAT, viral infection
Diospyrin, plant-derived bisnaphthoquinonoid, is known to have anticancer activity. However, pharmacological activity of diospyrin on viral infection is not well known. We investigated effects of diospyrin on macrophages induced by polyinosinic-polycytidylic acid (poly I:C), a mimic of double-stranded viral RNA. Various cytokines, intracellular calcium, nitric oxide (NO), phosphorylated p38 MAPK, and phosphorylated ERK1/2 as well as mRNA expressions of transcription factors were evaluated. Diospyrin significantly reduced NO production, granulocyte-macrophage colony-stimulating factor production, and intracellular calcium release in poly I:C-induced RAW 264.7. The phosphorylation of p38 MAPK and ERK1/2 was also significantly suppressed. Additionally, diospyrin inhibited mRNA levels of nitric oxide synthase 2, C/EBP homologous protein (CHOP), calcium/calmodulin dependent protein kinase II alpha, signal transducers and activators of transcription 1 (STAT1), STAT3, STAT4, Janus kinase 2, f... [more]
l-Ascorbic Acid and Thymoquinone Dual-Loaded Palmitoyl-Chitosan Nanoparticles: Improved Preparation Method, Encapsulation and Release Efficiency
Nurhanisah Othman, Siti Nurul Ain Md. Jamil, Mas Jaffri Masarudin, Luqman Chuah Abdullah, Rusli Daik, Nor Syazwani Sarman
February 22, 2021 (v1)
Subject: Biosystems
Keywords: chitosan, co-loaded nanoparticles, hydrophobic modification, l-ascorbic acid, thymoquinone
Encapsulation of dual compounds of different characters (hydrophilic and hydrophobic) in single nanoparticles carrier could reach the site of action more accurately with the synergistic effect but it is less investigated. In our previous findings, combined-compounds encapsulation and delivery from chitosan nanoparticles were impaired by the hydrophilicity of chitosan. Therefore, hydrophobic modification on chitosan with palmitic acid was conducted in this study to provide an amphiphilic environment for better encapsulation of antioxidants; hydrophobic thymoquinone (TQ) and hydrophilic l-ascorbic acid (LAA). Palmitoyl chitosan nanoparticles (PCNPs) co-loaded with TQ and LAA (PCNP-TQ-LAA) were synthesized via the ionic gelation method. Few characterizations were conducted involving nanosizer, Fourier-transform infrared spectroscopy (FTIR), field-emission scanning electron microscopy (FESEM) and high-resolution transmission electron microscopy (HRTEM). UV−VIS spectrophotometry was used to... [more]
Morphological Differentiation of Streptomyces clavuligerus Exposed to Diverse Environmental Conditions and Its Relationship with Clavulanic Acid Biosynthesis
Jeferyd Yepes-García, Carlos Caicedo-Montoya, Laura Pinilla, León F. Toro, Rigoberto Ríos-Estepa
February 22, 2021 (v1)
Subject: Biosystems
Keywords: cell morphology, clavulanic acid, shear stress, Streptomyces clavuligerus
Clavulanic acid (CA) is a potent inhibitor of class A β-lactamase enzymes produced by Streptomyces clavuligerus (S. clavuligerus) as a defense mechanism. Due to its industrial interest, the process optimization is under continuous investigation. This work aimed at identifying the potential relationship that might exist between S. clavuligerus ATCC 27064 morphology and CA biosynthesis. For this, modified culture conditions such as source, size, and age of inoculum, culture media, and geometry of fermentation flasks were tested. We observed that high density spore suspensions (1 × 107 spores/mL) represent the best inoculum source for S. clavuligerus cell suspension culture. Further, we studied the life cycle of S. clavuligerus in liquid medium, using optic, confocal, and electron microscopy; results allowed us to observe a potential relationship that might exist between the accumulation of CA and the morphology of disperse hyphae. Reactor geometries that increase shear stress promote sma... [more]
Pharmacological Properties and Chemical Profiles of Passiflora foetida L. Extracts: Novel Insights for Pharmaceuticals and Nutraceuticals
Annalisa Chiavaroli, Simonetta Cristina Di Simone, Kouadio Ibrahime Sinan, Maria Chiara Ciferri, Giancarlo Angeles Flores, Gokhan Zengin, Ouattara Katinan Etienne, Gunes Ak, Mohamad Fawzi Mahomoodally, Sharmeen Jugreet, Zoltán Cziáky, József Jekő, Lucia Recinella, Luigi Brunetti, Sheila Leone, Paola Angelini, Roberto Venanzoni, Luigi Menghini, Claudio Ferrante, Giustino Orlando
February 22, 2021 (v1)
Subject: Biosystems
Keywords: anti-oxidant/anti-inflammatory effects, bioinformatics/network pharmacology, chemical profile, neuroprotection, Passiflora foetida, skin protection
In the present study, Passiflora foetida extracts characterized by different polarities were studied for their phytochemical profile, enzyme inhibitory, and antioxidant potentials. In silico, in vitro and ex vivo studies were also carried out on methanol and water extracts for predicting pharmacokinetics and pharmacodynamics. In this regard, neuronal HypoE22 cells, isolated mouse skin tissues, and pathogen dermatophytes strains were exposed to extracts. Emphasis was given to the preventing effects induced by the extracts on hydrogen peroxide-induced alterations of prostaglandin E2 (PGE2), l-dopa, and serotonin. Chemical analysis revealed the presence of similar compounds in infusion and methanolic extracts. The ex vivo studies also showed protective skin properties by P. foetida water and methanol extracts, as evidenced by the decrease of hydrogen peroxide-induced PGE2 level. Additionally, the blunting effects on hydrogen peroxide-induced l-dopa levels are consistent with the anti-tyro... [more]
Screening and Application of Chitin Synthase Inhibitors
Xiaozai Shi, Shuo Qiu, Yingling Bao, Hanchi Chen, Yuele Lu, Xiaolong Chen
February 3, 2021 (v1)
Subject: Biosystems
Keywords: biological activity research, chitin synthase, inhibitors, maleimides
Chitin is an important part of the fungal cell wall, but is not found in plants and mammals, so chitin synthase (CHS) can be a green fungicide target. In this paper, 35 maleimide compounds were designed and synthesized as CHS inhibitors. All the screened compounds showed different degrees of CHS inhibitory activity and antifungal activity in vitro. In particular, the half−inhibitory concentration (IC50) value of compound 20 on CHS was 0.12 mM, and the inhibitory effect was better than that of the control polyoxin B (IC50 = 0.19 mM). At the same time, this compound also showed good antifungal activity and has further development value.
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