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Records with Subject: Biosystems
Showing records 1001 to 1025 of 1288. [First] Page: 37 38 39 40 41 42 43 44 45 Last
Activated Sludge Respiration Activity Inhibition Caused by Mobile Toilet Chemicals
Tomáš Vítěz, Monika Vítězová, Markéta Nováčková, Ivan Kushkevych
July 17, 2020 (v1)
Subject: Biosystems
Keywords: activated sludge, biological oxygen demand, bronopol, chemical toilets, formaldehyde
Ensuring high quality drinking water sources is important task nowadays. To reach this task, knowledge about the impact of different chemicals on aerobic wastewater treatment is mandatory. A mixture of different chemicals reaches wastewater treatment plant every day. With the growing discharge volume of mobile toilet chemicals, active substances in these products in the past years have been recorded. The respiratory activity of activated sludge was determined to show how mobile toilet chemicals and their active substances may affect the biological wastewater treatment process. The results show negative effect of formaldehyde and bronopol on respiratory activity of activated sludge. The wastewater treatment plants influent composition and size also play important roles. Results shows that activated sludge microorganisms at a wastewater treatment plant in industrial urban area may be adapted to the higher pollutants concentration. When mobile toilet tanks are directly discharged at small... [more]
Landfill GHG Reduction through Different Microbial Methane Oxidation Biocovers
Isabella Pecorini, Renato Iannelli
July 17, 2020 (v1)
Subject: Biosystems
Keywords: biocovers, biofiltration systems, greenhouse gases emissions mitigation, landfill odor mitigation, microbial methane oxidation
Emissions from daily and final covers of municipal solid waste (MSW) landfills can produce significant impacts on local and global environments. Simplifying, landfills can cause local impacts with odor emissions and global impacts with GHGs. This work focuses on hydrogen sulfide (H2S) and methane (CH4) emissions, with the aim of studying how it is possible to reduce their impacts by means of biofiltration systems. Both field and laboratory investigations have been carried out in Casa Rota Landfill (Tuscany, Italy). In the field trials, four pilot-scale biocovers made of compost from a source-selected organic fraction (SS compost), compost from a mechanical biological treatment plant—the residual fractions of the MSW, a mixed compost (SS-MSW compost) and sand were monitored in the daily cover area of the landfill, where high emissions were detected. Results showed that high CH4 and H2S emissions reductions occurred in the mixed SS-MSW compost plot, given a maximum methane oxidation effi... [more]
Metabolic Regulation Analysis of Ajmalicine Biosynthesis Pathway in Catharanthus roseus (L.) G. Don Suspension Culture Using Nanosensor
Ghazala Ambrin, Hayssam M. Ali, Altaf Ahmad
July 17, 2020 (v1)
Subject: Biosystems
Keywords: ajmalicine, Catharanthus roseus, fluxomics, nanosensor, TIA pathway
Ajmalicine is one of the most popular antihypertensive drugs obtained from the root barks of Cathranthus roseus (L.) G. Don and Rauvolfia serpentine (L.) Benth. ex Kurz. It has also potential antimicrobial, cytotoxic, central depressant and antioxidant activities. As the demand for the alkaloid is significantly high, metabolic engineering approaches are being tried to increase its production in both homologous and heterologous systems. The metabolic engineering approach requires knowledge of the metabolic regulation of the alkaloid. For understanding the metabolic regulation, fluxomic analysis is important as it helps in understanding the flux of the alkaloid through the complicated metabolic pathway. The present study was conducted to analyse the flux analysis of the ajmalicine biosynthesis, using a genetically encoded Fluorescent Resonance Energy Transfer FRET-based nanosensor for ajmalicine (FLIP-Ajn). Here, we have silenced six important genes of terpenoid indole alkaloid (TIA), na... [more]
Ultrasensitive Ti3C2TX MXene/Chitosan Nanocomposite-Based Amperometric Biosensor for Detection of Potential Prostate Cancer Marker in Urine Samples
Stefania Hroncekova, Tomas Bertok, Michal Hires, Eduard Jane, Lenka Lorencova, Alica Vikartovska, Aisha Tanvir, Peter Kasak, Jan Tkac
July 17, 2020 (v1)
Subject: Biosystems
Keywords: biosensor, MXene, nanocomposite, prostate cancer, sarcosine, sarcosine oxidase
Two-dimensional layered nanomaterial Ti3C2TX (a member of the MXene family) was used to immobilise enzyme sarcosine oxidase to fabricate a nanostructured biosensor. The device was applied for detection of sarcosine, a potential prostate cancer biomarker, in urine for the first time. The morphology and structures of MXene have been characterised by atomic force microscopy (AFM) and scanning electron microscopy (SEM). Electrochemical measurements, SEM and AFM analysis revealed that MXene interfaced with chitosan is an excellent support for enzyme immobilisation to fabricate a sensitive biosensor exhibiting a low detection limit of 18 nM and a linear range up to 7.8 µM. The proposed biosensing method also provides a short response time of 2 s and high recovery index of 102.6% for detection of sarcosine spiked into urine sample in a clinically relevant range.
Review of Evidence Available on Hesperidin-Rich Products as Potential Tools against COVID-19 and Hydrodynamic Cavitation-Based Extraction as a Method of Increasing Their Production
Francesco Meneguzzo, Rosaria Ciriminna, Federica Zabini, Mario Pagliaro
July 7, 2020 (v1)
Subject: Biosystems
Keywords: citrus fruits, coronavirus, COVID-19, flavonoids, hesperetin, hesperidin, hydrodynamic cavitation, pectin, SARS-CoV-2
Based on recent computational and experimental studies, hesperidin, a bioactive flavonoid abundant in citrus peel, stands out for its high binding affinity to the main cellular receptors of SARS-CoV-2, outperforming drugs already recommended for clinical trials. Thus, it is very promising for prophylaxis and treatment of COVID-19, along with other coexistent flavonoids such as naringin, which could help restraining the proinflammatory overreaction of the immune system. Controlled hydrodynamic cavitation processes showed the highest speed, effectiveness and efficiency in the integral and green aqueous extraction of flavonoids, essential oils and pectin from citrus peel waste. After freeze-drying, the extracted pectin showed high quality and excellent antioxidant and antibacterial activities, attributed to flavonoids and essential oils adsorbed and concentrated on its surface. This study reviews the recent evidence about hesperidin as a promising molecule, and proposes a feasible and aff... [more]
Controlled Drug Delivery Vehicles in Veterinary Oncology: State-of-the-Art and Future Directions
Patricia de Faria Lainetti, Fernanda Zuliani, Antonio Fernando Leis-Filho, Ricardo Henrique Fonseca Alves, Carlos Eduardo Fonseca-Alves
July 7, 2020 (v1)
Subject: Biosystems
Keywords: dogs, doxorubicin, nanoparticles, nanotechnology
Controlled drug delivery systems can be used to carry several anticancer agents, including classical chemotherapeutic agents such as doxorubicin, paclitaxel or cisplatin, and are also used for the encapsulation of tyrosine kinase inhibitors and monoclonal antibodies. Usually, the controlled systems are used to decrease drug toxicity, increase local drug concentration or target specific organs or systems. In dogs, liposomal doxorubicin is the most known controlled drug delivery vehicle in veterinary medicine. However, several antitumor drugs can be encapsulated within these systems. Since the delivery vehicles are a relatively new topic in veterinary oncology, this review aims to discuss the current knowledge regarding the controlled drug delivery vehicles and discuss the current challenges and future direction of its use in veterinary oncology.
Comprehensive Screening of Drug Encapsulation and Co-Encapsulation into Niosomes Produced Using a Microfluidic Device
Sameer Joshi, Roderica White, Rajnish Sahu, Vida A. Dennis, Shree R. Singh
July 7, 2020 (v1)
Subject: Biosystems
Keywords: cholesterol, encapsulation, microfluidics, niosomes, non-ionic surfactants
Microfluidics is a very facile and fast method of particulate production. Besides, it enables the manufacturing of size tuned particulate systems. Niosomes due to structural similarities have importance as alternative drug delivery systems to liposomes. Niosomes can be encapsulated or co-encapsulated with hydrophilic and lipophilic drugs. The research presented here includes the optimization of method parameters for niosome production as well as evaluation of the efficiency of microfluidics to encapsulate and co-encapsulate the drugs. For this purpose, metformin (MET) and garcinol (GC) were the model drugs. Two different non-ionic surfactants (NIS), namely Tween-20 and Span-60 with significant difference in hydrophilic-lipophilic balance (HLB) value, were chosen to analyze their efficiency to form niosomes and encapsulate one or more drugs.
Controlling the Skin Barrier Quality through the Application of Polymeric Films Containing Microspheres with Encapsulated Plant Extract
Justyna Kozlowska, Bartosz Tylkowski, Natalia Stachowiak, Weronika Prus-Walendziak
July 2, 2020 (v1)
Subject: Biosystems
Keywords: Calendula officinalis flower extract, encapsulation, microspheres, polymer films, skin barrier, sodium alginate, starch, transepidermal water loss
Human skin has protective functions and it is a barrier that protects the interior of the body from harmful environmental factors and pathogen penetration. An important role of the skin is also to prevent the loss of water from the body and if the skin barrier is damaged, the amount of water emitted from the internal environment is increased. Therefore, it is crucial to recovery and maintenance of epidermal barrier integrity. The aim of the current work was to encapsulate Calendula officinalis flower extract in gelatin microspheres and then incorporation microspheres into thin polymeric films made from sodium alginate or mixture of sodium alginate and starch. Such materials may find applications in the cosmetic field for example in the preparation of masks for skin, according to the Calendula officinalis flower extract wide influence on skin condition. Thus, the release profile of this extract from the materials was tested under conditions corresponding to the skin (pH 5.4, 37 °C). The... [more]
Pollen Bee Aqueous Extract-Based Synthesis of Silver Nanoparticles and Evaluation of Their Anti-Cancer and Anti-Bacterial Activities
Hanan M. Al-Yousef, Musarat Amina, Ali S. Alqahtani, Mohammed S. Alqahtani, Abdul Malik, Mohammad Rafe Hatshan, Mohammed Rafiq H. Siddiqui, Mujeeb Khan, Mohammed Rafi Shaik, Mohammad Shamsul Ola, Rabbani Syed
July 2, 2020 (v1)
Subject: Biosystems
Keywords: anti-bacterial, anti-cancer, bee pollen aqueous extract, eco-friendly, silver nanoparticles
Bee pollens are rich source of essential amino acids and are often considered as complete food for human beings. Herein, we exploited the potential reducing abilities of Bee pollens extract for the eco-friendly preparation of silver nanoparticles (AgNPs-G). The resulting NPs were characterized using a combination of microscopic and spectroscopic techniques. The analyses confirm the formation of spherical Ag NPs. AgNPs-G obtained from the aqueous extract of bee pollens was used to study their antibacterial properties against Gram-positive and Gram-negative microbes using the Minimum Inhibitory Concentration 50 (MIC50) method. The antibacterial properties of AgNPs-G were compared to the properties of chemically synthesized Ag NPs (AgNPs-C) using sodium borohydride as a reducing agent. The green synthesized nanoparticles (AgNPs-G) exhibited a better antibacterial activity against most of the studied strains when compared to the chemically synthesized Ag NPs (AgNPs-C). In addition, the ant... [more]
The Cultivation of Lipid-Rich Microalgae Biomass as Anaerobic Digestate Valorization Technology—A Pilot-Scale Study
Marcin Dębowski, Marcin Zieliński, Marta Kisielewska, Joanna Kazimierowicz, Magda Dudek, Izabela Świca, Aleksandra Rudnicka
July 2, 2020 (v1)
Subject: Biosystems
Keywords: anaerobic digestate, bio-oil, microalgae, photobioreactor
The aim of the study was to determine the use of digestate from anaerobic digestion of dairy wastewater as a culture medium for microalgae to obtain bio-oil. The experiments were conducted at a small scale in a closed raceway pond. The efficiency of the microalgae biomass production, the digestate treatment efficiency as well as the content and properties of the bio-oil obtained from the microalgal cells were analyzed. The produced biomass concentration was about 3000 ± 10.5 mg dry biomass/L, with an average growth rate of 160 ± 6.6 mgdm/L·d. The efficiency of organic compound and nutrient removal was above 90%. The bio-oil content in the biomass was about 20%. Based on the results of the study, a concept for technical-scale technology was developed.
Metabolic Efficiency of Sugar Co-Metabolism and Phenol Degradation in Alicyclobacillus acidocaldarius for Improved Lignocellulose Processing
Ashley E. Beck
July 2, 2020 (v1)
Subject: Biosystems
Keywords: co-metabolism, dynamic flux balance analysis, elementary flux mode analysis, resource allocation, thermoacidophile
Substrate availability plays a key role in dictating metabolic strategies. Most microorganisms consume carbon/energy sources in a sequential, preferential order. The presented study investigates metabolic strategies of Alicyclobacillus acidocaldarius, a thermoacidophilic bacterium that has been shown to co-utilize glucose and xylose, as well as degrade phenolic compounds. An existing metabolic model was expanded to include phenol degradation and was analyzed with both metabolic pathway and constraint-based analysis methods. Elementary flux mode analysis was used in conjunction with resource allocation theory to investigate ecologically optimal metabolic pathways for different carbon substrate combinations. Additionally, a dynamic version of flux balance analysis was used to generate time-resolved simulations of growth on phenol and xylose. Results showed that availability of xylose along with glucose did not predict enhanced growth efficiency beyond that of glucose alone, but did predi... [more]
Synthesis and Characterization of New Fluoro/Trifluoromethyl-Substituted Acylthiourea Derivatives with Promising Activity against Planktonic and Biofilm-Embedded Microbial Cells
Carmen Limban, Diana Camelia Nuta, Alexandru Vasile Missir, Roxana Roman, Miron Teodor Caproiu, Florea Dumitrascu, Lucia Pintilie, Amalia Stefaniu, Mariana Carmen Chifiriuc, Marcela Popa, Irina Zarafu, Andreea Letiția Arsene, Cristina Elena Dinu Pirvu, Denisa Ioana Udeanu, Ioana Raluca Papacocea
July 2, 2020 (v1)
Subject: Biosystems
Keywords: 13C-NMR, 1H-NMR, anti-biofilm activity, antimicrobial activity, antioxidant activity, benzamides, IR spectroscopy, thiourea derivatives
The aim of this study was preparation of new derivatives based on 2-((4-chlorophenoxy)methyl)-N-(arylcarbamothioyl)benzamide structure; the new compounds were characterized by IR, NMR (1H, 13C) spectroscopy, and elemental analysis. The obtained compounds were evaluated for their in vitro antimicrobial activity against planktonic and biofilm-embedded microbial cells (Staphylococcus aureus, Enterococcus faecalis, Escherichia coli, Pseudomonas aeruginosa, Candida albicans), by qualitative and quantitative assays. Some of the compounds revealed promising antibacterial and antifungal activities, with low minimum inhibitory concentration values between 0.15 and 2.5 mg/mL and minimal biofilm eradication concentrations of 0.019−2.5 mg/mL. To investigate the potential target of their antibacterial activity, in silico drug-likeness and molecular docking screenings on Staphylococcus aureus DNA gyrase were performed. The compound with the best antibacterial activity (1g) was docked into topoisomer... [more]
Formulation and Functional Properties of Whey Protein-Based Tissue Adhesive Using Totarol as an Antimicrobial Agent
Yifan Hou, Xiaonan Zhang, Cuina Wang, Mingruo Guo
June 23, 2020 (v1)
Subject: Biosystems
Keywords: functional properties, tissue adhesive, totarol, whey protein
Tissue adhesives have been widely used in surgical procedures. Compared to traditional surgical sutures, tissue adhesives provide fast bonding experiences and full closure of wounds. However, current tissue adhesives are mostly fossil-based synthetic products. Therefore, it is of great significance to explore the use of natural materials in tissue adhesives. Whey is a low-end byproduct of cheese manufacturing. Whey protein, a group of small globular proteins, can exhibit adhesive properties if their structures are modified by physical or chemical means. The objectives of this study were to investigate the functional and structural properties of whey protein-based tissue adhesive, along with the antibacterial effect of totarol, a natural antimicrobial agent. Whey protein isolate (WPI) solutions (25%−33% protein) were mixed with different levels (0.1%−0.3% w/w) of totarol. The mixtures were analyzed for total plate count and yeast and mold count. The lap-shear bonding strength was tested... [more]
Effect of Bone Morphogenic Protein-2-Loaded Mesoporous Strontium Substitution Calcium Silicate/Recycled Fish Gelatin 3D Cell-Laden Scaffold for Bone Tissue Engineering
Chun-Ta Yu, Fu-Ming Wang, Yen-Ting Liu, Hooi Yee Ng, Yi-Rong Jhong, Chih-Hung Hung, Yi-Wen Chen
June 23, 2020 (v1)
Subject: Biosystems
Keywords: bioprinting, bone morphogenetic protein, bone regeneration, cell-laden scaffold, mesoporous material, recycling material, strontium-doped calcium silicate
Bone has a complex hierarchical structure with the capability of self-regeneration. In the case of critical-sized defects, the regeneration capabilities of normal bones are severely impaired, thus causing non-union healing of bones. Therefore, bone tissue engineering has since emerged to solve problems relating to critical-sized bone defects. Amongst the many biomaterials available on the market, calcium silicate-based (CS) cements have garnered huge interest due to their versatility and good bioactivity. In the recent decade, scientists have attempted to modify or functionalize CS cement in order to enhance the bioactivity of CS. Reports have been made that the addition of mesoporous nanoparticles onto scaffolds could enhance the bone regenerative capabilities of scaffolds. For this study, the main objective was to reuse gelatin from fish wastes and use it to combine with bone morphogenetic protein (BMP)-2 and Sr-doped CS scaffolds to create a novel BMP-2-loaded, hydrogel-based mesopo... [more]
Holographic Imaging of Insect Cell Cultures: Online Non-Invasive Monitoring of Adeno-Associated Virus Production and Cell Concentration
Daniel A. M. Pais, Paulo R. S. Galrão, Anastasiya Kryzhanska, Jérémie Barbau, Inês A. Isidro, Paula M. Alves
June 23, 2020 (v1)
Subject: Biosystems
Keywords: AAV-adeno-associated virus, cell culture monitoring, digital holographic microscopy, insect cell-baculovirus, process analytical technology
The insect cell-baculovirus vector system has become one of the favorite platforms for the expression of viral vectors for vaccination and gene therapy purposes. As it is a lytic system, it is essential to balance maximum recombinant product expression with harvest time, minimizing product exposure to detrimental proteases. With this purpose, new bioprocess monitoring solutions are needed to accurately estimate culture progression. Herein, we used online digital holographic microscopy (DHM) to monitor bioreactor cultures of Sf9 insect cells. Batches of baculovirus-infected Sf9 cells producing recombinant adeno-associated virus (AAV) and non-infected cells were used to evaluate DHM prediction capabilities for viable cell concentration, culture viability and AAV titer. Over 30 cell-related optical attributes were quantified using DHM, followed by a forward stepwise regression to select the most significant (p < 0.05) parameters for each variable. We then applied multiple linear regres... [more]
Bioactivity of Selected Phenolic Acids and Hexane Extracts from Bougainvilla spectabilis and Citharexylum spinosum on the Growth of Pectobacterium carotovorum and Dickeya solani Bacteria: An Opportunity to Save the Environment
Nader A. Ashmawy, Said I. Behiry, Asma A. Al-Huqail, Hayssam M. Ali, Mohamed Z. M. Salem
June 23, 2020 (v1)
Subject: Biosystems
Keywords: Bougainvilla, Citharexylum extract, Dickeya, ecofriendly environmental agents, Pectobacterium, phenolic acids
Phenolic acids and natural extracts, as ecofriendly environmental agents, can be used as bio bactericides against the growth of plant pathogenic bacteria. In this study, isolation trails from infected potato tubers and stems that showed soft rot symptoms in fields revealed two soft rot bacterial isolates and were initially identified through morphological, physiological, and pathogenicity tests. The molecular characterization of these isolates via PCR, based on the 16S rRNA region, was carried out by an analysis of the DNA sequence via BLAST and Genbank, and showed that the soft rot bacterial isolates belong to Pectobacterium carotovorum subsp. carotovorum (PCC1) and Dickeya solani (Ds1). The in vitro results of the tested phenolic acids against the cultured bacterial isolates proved that concentrations of 800, 1600, and 3200 μg/mL were the most effective. Ferulic acid was the potent suppressive phenolic acid tested against the Ds1 isolate, with an inhibition zone ranging from 6.00 to... [more]
Polyphenol Profile and Antimicrobial and Cytotoxic Activities of Natural Mentha × piperita and Mentha longifolia Populations in Northern Saudi Arabia
Hosam O. Elansary, Agnieszka Szopa, Paweł Kubica, Halina Ekiert, Marta Klimek-Szczykutowicz, Diaa O. El-Ansary, Eman A. Mahmoud
June 23, 2020 (v1)
Subject: Biosystems
Keywords: antibacterial, antifungal, antiproliferative, cytotoxic, flavonoids, horse mint, leaf extract, phenolic acids
New sources of polyphenols with anticancer, antioxidant, and antimicrobial properties in arid environments are critical for the development of alternative medicines and natural remedies. This study explored the polyphenol profiles and biological activities of methanolic leaf extracts from natural Mentha × piperita and Mentha longifolia populations in northern Saudi Arabia. Chromatographic analyses identified several polyphenols in M. × piperita including phenolic acids: rosmarinic acid (1547.6 mg/100 g DW (dry weight)), cryptochlorogenic acid (91.7 mg/100 g DW), and chlorogenic acid (69.4 mg/100 g DW), as well as flavonoids: naringin (328.8 mg/100 g DW) and cynaroside (162.8 mg/100 g DW). The major polyphenols in M. longifolia were: rosmarinic acid (781.6 mg/100 g DW), cryptochlorogenic acid (191.1 mg/100 g DW), p-coumaric acid (113.0 mg/100 g DW), m-coumaric acid (112.2 mg/100 g DW), and chlorogenic acid (63.8 mg/100 g DW). M. × piperita and M. longifolia leaf extracts had high antiox... [more]
Microbial Natural Products in Drug Discovery
Ahmed S. Abdel-Razek, Mehrez E. El-Naggar, Ahmed Allam, Osama M. Morsy, Sarah I. Othman
June 23, 2020 (v1)
Subject: Biosystems
Keywords: drug delivery, microbial products, natural products
Over a long period of time, humans have explored many natural resources looking for remedies of various ailments. Traditional medicines have played an intrinsic role in human life for thousands of years, with people depending on medicinal plants and their products as dietary supplements as well as using them therapeutically for treatment of chronic disorders, such as cancer, malaria, diabetes, arthritis, inflammation, and liver and cardiac disorders. However, plant resources are not sufficient for treatment of recently emerging diseases. In addition, the seasonal availability and other political factors put constrains on some rare plant species. The actual breakthrough in drug discovery came concurrently with the discovery of penicillin from Penicillium notatum in 1929. This discovery dramatically changed the research of natural products and positioned microbial natural products as one of the most important clues in drug discovery due to availability, variability, great biodiversity, u... [more]
Ability of Trichoderma hamatum Isolated from Plastics-Polluted Environments to Attack Petroleum-Based, Synthetic Polymer Films
Kateřina Malachová, Čeněk Novotný, Grażyna Adamus, Nadia Lotti, Zuzana Rybková, Michelina Soccio, Pavlína Šlosarčíková, Vincent Verney, Fabio Fava
June 23, 2020 (v1)
Subject: Biosystems
Keywords: bacteria, fungi, plastic-polymer degradation, screening, Trichoderma hamatum
Microorganisms colonizing plastic waste material collected in composting-, landfill-, and anaerobic digestion plants were isolated to obtain novel strains maximally adapted to the degradation of plastics due to long-term contact with plastic polymers. Twenty-six bacterial strains were isolated and identified by the 16 S rRNA method, and eighteen strains of yeasts and fungi using 18 S rRNA and the internal transcribed spacer ITS sequencing of the 18 S rRNA gene. In selected strains, the ability to degrade linear low-density polyethylene (LLDPE), low-density polyethylene (LDPE), polystyrene (PS), and polyvinyl chloride (PVC) was tested in aerobic liquid-medium cultures. An oxidative, two-step pretreatment of LLDPE and LDPE using γ- or UV-irradiation followed by a high-temperature treatment was carried out, and the pretreated plastics were also included in the degradation experiments. The respective weight losses after biodegradation by Trichoderma hamatum were: virgin and γ/T90-pretreate... [more]
Novel Purification Process for Amyloid Beta Peptide(1-40)
Kenji Usui, Shin-ichiro Yokota, Kazuya Iwata, Yoshio Hamada
June 23, 2020 (v1)
Subject: Biosystems
Keywords: aggregating peptide, amyloid beta peptide, difficult sequence, peptide synthesis, purification, reduction, solid-phase synthesis
Amyloid beta peptide (Aβ)-related studies require an adequate supply of purified Aβ peptide. However, Aβ peptides are “difficult sequences” to synthesize chemically, and low yields are common due to aggregation during purification. Here, we demonstrate an easier synthesis, deprotection, reduction, cleavage, and purification process for Aβ(1-40) using standard 9-fluorenylmethyloxycarbonyl (Fmoc)-protected amino acids and solid-phase peptide synthesis (SPPS) resin [HMBA (4-hydroxymethyl benzamide) resin] that provides higher yields of Aβ(1-40) than previous standard protocols. Furthermore, purification requires a similar amount of time as conventional purification processes, although the peptide must be cleaved from the resin immediately prior to purification. The method described herein is not limited to the production of Aβ(1-40), and can be used to synthesize other easily-oxidized and aggregating sequences. Our proposed methodology will contribute to various fields using “difficult se... [more]
Resveratrol Nanoparticles: A Promising Therapeutic Advancement over Native Resveratrol
Ill-Min Chung, Umadevi Subramanian, Prabhu Thirupathi, Baskar Venkidasamy, Ramkumar Samynathan, Baniekal Hiremath Gangadhar, Govindasamy Rajakumar, Muthu Thiruvengadam
June 23, 2020 (v1)
Subject: Biosystems
Keywords: biomedical activities, nanoparticles, resveratrol
The importance of fruit-derived resveratrol (RES) in the treatment of various diseases has been discussed in various research publications. Those research findings have indicated the ability of the molecule as therapeutic in the context of in vitro and in vivo conditions. Mostly, the application of RES in in vivo conditions, encapsulation processes have been carried out using various nanoparticles that are made of biocompatible biomaterials, which are easily digested or metabolized, and RES is absorbed effectively. These biomaterials are non-toxic and are safe to be used as components in the biotherapeutics. They are made from naturally available by-products of food materials like zein or corn or components of the physiological system as with lipids. The versatility of the RES nanoparticles in their different materials, working range sizes, specificity in their targeting in various human diseases, and the mechanisms associated with them are discussed in this review.
Maximization of Siderophores Production from Biocontrol Agents, Pseudomonas aeruginosa F2 and Pseudomonas fluorescens JY3 Using Batch and Exponential Fed-Batch Fermentation
Gaber Attia Abo-Zaid, Nadia Abdel-Mohsen Soliman, Ahmed Salah Abdullah, Ebaa Ebrahim El-Sharouny, Saleh Mohamed Matar, Soraya Abdel-Fattah Sabry
June 23, 2020 (v1)
Subject: Biosystems
Keywords: antagonism, batch fermentation, bio-friendly formulations, biocontrol, exponential fed-batch fermentation, Pseudomonas, siderophores
Twenty fluorescent Pseudomonas isolates were tested for their ability to produce siderophores on chrome azurol S (CAS) agar plates and their antagonistic activity against six plant pathogenic fungal isolates was assessed. Scaling-up production of siderophores from the promising isolates, P. aeruginosa F2 and P. fluorescens JY3 was performed using batch and exponential fed-batch fermentation. Finally, culture broth of the investigated bacterial isolates was used for the preparation of two economical bioformulations for controlling Fusarium oxysporum and Rhizoctonia solani. The results showed that both isolates yielded high siderophore production and they were more effective in inhibiting the mycelial growth of the tested fungi compared to the other bacterial isolates. Exponential fed-batch fermentation gave higher siderophore concentrations (estimated in 10 µL), which reached 67.05% at 46 h and 45.59% at 48 h for isolates F2 and JY3, respectively, than batch fermentation. Formulated P.... [more]
Techno-Economic Assessment of Cell-Free Synthesis of Monoclonal Antibodies Using CHO Cell Extracts
Vaishali Thaore, Dimitrios Tsourapas, Nilay Shah, Cleo Kontoravdi
June 23, 2020 (v1)
Subject: Biosystems
Keywords: cell extracts, Chinese hamster ovary cells, in vitro expression, monoclonal antibodies, process economics, recombinant proteins, stable gene expression, transient gene expression
Cell-free protein synthesis (CFPS) is an emerging tool for the rapid production of difficult-to-express proteins as well as for identifying protein synthesis bottlenecks. In CFPS, the biotic phase is substituted by extracts of living cells devoid of any of their own genetic material. The main advantage is that these systems delineate cell growth from recombinant protein production, enabling the expression of targets that would otherwise place too big a burden on living cells. We have conducted a techno-economic analysis of a CFPS system to produce monoclonal antibodies (mAbs) using extracts of Chinese hamster ovary (CHO) cells. We compare the performance of the CFPS system with two alternative production strategies: stable and transient gene expression in CHO cells. Our assessment shows that the viability of CFPS for mAb production requires a significant increase in the product yield and the recycling of high-cost components such as DNA. Nevertheless, CFPS shows significant promise for... [more]
Concentration of Lipase from Aspergillus oryzae Expressing Fusarium heterosporum by Nanofiltration to Enhance Transesterification
Hans Wijaya, Kengo Sasaki, Prihardi Kahar, Emmanuel Quayson, Nova Rachmadona, Jerome Amoah, Shinji Hama, Chiaki Ogino, Akihiko Kondo
June 22, 2020 (v1)
Subject: Biosystems
Keywords: fatty acid methyl ester, Fusarium heterosporum, lipase, nanofiltration
Nanofiltration membrane separation is an energy-saving technology that was used in this study to concentrate extracellular lipase and increase its total activity for biodiesel production. Lipase was produced by recombinant Aspergillus oryzae expressing Fusarium heterosporum lipase (FHL). A sulfonated polyethersulfone nanofiltration membrane, NTR-7410, with a molecular weight cut-off of 3 kDa was used for the separation, because recombinant lipase has a molecular weight of approximately 20 kDa, which differs from commercial lipase at around 30 kDa for CalleraTM Trans L (CalT). After concentration via nanofiltration, recombinant lipase achieved a 96.8% yield of fatty acid methyl ester (FAME) from unrefined palm oil, compared to 50.2% for CalT in 24 h. Meanwhile, the initial lipase activity (32.6 U/mL) of recombinant lipase was similar to that of CalT. The composition of FAME produced from recombinant concentrated lipase, i.e., C14:1, C16:0, C18:0, C18:1 cis, and C18:2 cis were 0.79%, 34.... [more]
Saudi Rosmarinus officinalis and Ocimum basilicum L. Polyphenols and Biological Activities
Hosam O. Elansary, Agnieszka Szopa, Paweł Kubica, Halina Ekiert, Diaa O. El-Ansary, Fahed A. Al-Mana, Eman A. Mahmoud
June 22, 2020 (v1)
Subject: Biosystems
Keywords: antibacterial, antifungal, antioxidant, antiproliferative, cytotoxicity, flavonoids, leaf extract, Ocimum basilicum, phenolic acids, Rosmarinus officinalis
Investigating the polyphenolic profile of natural Rosmarinus officinalis and Ocimum basilicum populations may reveal essential compounds that have biological activities. Natural populations of R. officinalis and O. basilicum in Northern Riyadh were investigated by HPLC-DAD analyses. Several polyphenols, including rosmarinic acid, gentisic acid, 3,4-dihydroxyphenylacetic acid, rutoside, and others, out of 38 screened were confirmed. Rosmarinic acid was the major polyphenol in both of R. officinalis and O. basilicum. R. officinalis methanolic leaf extracts contained other phenols such as gentisic acid while O. basilicum contained also 3,4-dihydroxyphenylacetic acid and rutoside as well as others. R. officinalis showed higher antioxidant activities than O. basilicum using 2,2-diphenyl-1-picrylhydrazyl (DPPH), ferric reducing antioxidant power (FRAP), and β-carotene bleaching assays. These higher activities are associated with a higher composition of rosmarinic acid in leaf extracts. The a... [more]
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