Browse
Subjects
Records with Subject: Biosystems
Showing records 1089 to 1113 of 1288. [First] Page: 1 41 42 43 44 45 46 47 48 49 Last
Theoretical and Experimental Approaches Aimed at Drug Design Targeting Neurodegenerative Diseases
Samuel Morales-Navarro, Luis Prent-Peñaloza, Yeray A. Rodríguez Núñez, Laura Sánchez-Aros, Oscar Forero-Doria, Wendy González, Nuria E. Campilllo, Miguel Reyes-Parada, Ana Martínez, David Ramírez
January 19, 2020 (v1)
Subject: Biosystems
Keywords: chemoinformatics, drug design, Green chemistry, medical chemistry, molecular modeling, neurodegenerative diseases
In recent years, green chemistry has been strengthening, showing how basic and applied sciences advance globally, protecting the environment and human health. A clear example of this evolution is the synergy that now exists between theoretical and computational methods to design new drugs in the most efficient possible way, using the minimum of reagents and obtaining the maximum yield. The development of compounds with potential therapeutic activity against multiple targets associated with neurodegenerative diseases/disorders (NDD) such as Alzheimer’s disease is a hot topic in medical chemistry, where different scientists from various disciplines collaborate to find safe, active, and effective drugs. NDD are a public health problem, affecting mainly the population over 60 years old. To generate significant progress in the pharmacological treatment of NDD, it is necessary to employ different experimental strategies of green chemistry, medical chemistry, and molecular biology, coupled wi... [more]
Toxicological Activity of Some Plant Essential Oils Against Tribolium castaneum and Culex pipiens Larvae
Ahmed M. El-Sabrout, Mohamed Z. M. Salem, May Bin-Jumah, Ahmed A. Allam
January 19, 2020 (v1)
Subject: Biosystems
Keywords: Culex mosquitoes, essential oils, physiological effects, red flour beetle
In the present work, essential oils (EOs) from Schinus terebinthifolius (ripe and unripe fruits and leaves), Origanum majorana (air-dried aerial parts), and Psidium guajava (leaves) were assayed for their insecticidal activity against red flour beetle (Tribolium castaneum) and Culex mosquito larvae (Culex pipiens). Several components were identified in the EOs using Gas chromatography−mass spectrometry (GC/MS), of which Δ-3-carene (25.9%), γ-terpinene (19.4), and γ-elemene (7.1%) were the major ones in S. terebinthifolius ripe fruits, α-pinene (48.9%), germacrene D (12.9%), and α-thujene (7.7%) in S. terebinthifolius unripe fruits, γ-elemene (11.7%), spathulenol (10.1%), β-elemene (9.2%), and p-cymene (9.1%) in S. terebinthifolius leaves, α-pinene (25.5%), (E)-caryophyllene (15.7%), (E)-nerolidol (16.7%), and cedran-8-ol (8.8%) in P. guajava leaves, and terpinen-4-ol (21.7%), γ-terpinene (16.5%), and sabinene (10.1%) in O. majorana air-dried aerial parts. The lethal concentration (LC50... [more]
Fluid Flow in Cotton Textile: Effects of Wollastonite Nanosuspension and Aspergillus Niger Fungus
Ayoub Esmailpour, Hamid R. Taghiyari, Reza Majidi Najafabadi, Amin Kalantari, Antonios N. Papadopoulos
January 7, 2020 (v1)
Subject: Biosystems
Keywords: Aspergillus niger, biological resistance, cotton textile, permeability, wollastonite
Aspergillus niger is a common contaminant in food industry, laboratories, and also a potential threat to biological works of art in museums. Cotton textiles have frequently been used in museums for canvas paintings. In the present project, the effect of Aspergillus niger on fluid flow rate of nanowollastonite-impregnated cotton textile specimens was investigated. Cotton specimens were impregnated with nanowollastonite (NW) suspension at four concentrations of 10%, 20%, 30%, and 40% to be further compared with control specimens. Results showed that fluid flow in cotton textile was as high as 361.3 cm3·s−1 due to its high porous structure and very low compactness of fibers (low density). Impregnation with NW did not have a significant effect on fluid flow in cotton textile. Exposure to Aspergillus niger increased fluid flow in control specimens as a result of deterioration of cotton fibers. Exposure of NW-impregnated specimens at concentrations more than 20% to Aspergillus niger did not... [more]
Marine Algae: A Potential Resource of Anti-HSV Molecules
Mohamad Fawzi Mahomoodally, Devina Lobine, Kannan R. R. Rengasamy, Shanmugaraj Gowrishankar, Devesh Tewari, Gokhan Zengin, Doo Hwan Kim, Iyyakkannu Sivanesan
January 2, 2020 (v1)
Subject: Biosystems
Keywords: antiviral, brown algae, green algae, Herpesviridae, human infections, natural product, phytochemicals, red algae, sulfated polysaccharides, virus
Herpes simplex viruses (HSVs) are common human pathogens belonging to the subfamily alpha-herpesvirinae that trigger severe infections in neonates and immunocompromised patients. After primary infection, the HSVs establish a lifelong latent infection in the vegetative neural ganglia of their hosts. HSV infections contribute to substantial disease burden in humans as well as in newborns. Despite a fair number of drugs being available for the treatment of HSV infections, new, effective, and safe antiviral agents, exerting different mechanisms of action, are urgently required, mainly due to the increasing number of resistant strains. Accumulating pieces of evidence have suggested that structurally diverse compounds from marine algae possess promising anti-HSV potentials. Several studies have documented a variety of algal polysaccharides possessing anti-HSV activity, including carrageenan and fucan. This review aimed to compile previous anti-HSV studies on marine algae−derived compounds, e... [more]
Performance and Microbial Community Structure of Anaerobic Membrane Bioreactor for Lipids-Rich Kitchen Waste Slurry Treatment: Mesophilic and Thermophilic Processes
Xiaolan Xiao, Wansheng Shi, Wenquan Ruan
January 2, 2020 (v1)
Subject: Biosystems
Keywords: anaerobic microorganism, digestion performance, high lipids wastewater, long chain fatty acid, membrane filtration
The performance and microbial community structure for treating lipids-rich kitchen waste slurry in mesophilic Anaerobic Membrane Bioreactor (m-AnMBR) and thermophilic AnMBR (t-AnMBR) were compared in this study. Higher Organic Loading Rate (OLR) of 12 kg-COD/(m3·d), better Chemical Oxygen Demand (COD) removal efficiency over 98%, stronger stability with Volatile Fatty Acids (VFAs)/alkalinity below 0.04, higher flux with 18 L/(m2·h) and lower Long Chain Fatty Acids (LCFAs) concentration of 550 mg/L were obtained in the m-AnMBR. Directly increasing temperature from 39 to 55 °C resulted in a collapse of the t-AnMBR. Acclimation via gradually increasing temperature made the t-AnMBR run successfully with lower OLR and COD removal efficiency of 7.5 kg-COD/(m3·d) and 96%. An obvious discrepancy of microbial community structure was presented between the m-AnMBR and t-AnMBR via the 16S rRNA gene sequence analysis. The Methanomethylovorans and Methanoculleus were dominant in the t-AnMBR instead... [more]
Antioxidant Activity and Selenium and Polyphenols Content from Selected Medicinal Plants Natives from Various Areas Abundant in Selenium (Poland, Lithuania, and Western Ukraine)
Zofia Sotek, Bożenna Białecka, Bogumiła Pilarczyk, Radosław Drozd, Renata Pilarczyk, Agnieszka Tomza-Marciniak, Barna Kruzhel, Halyna Lysak, Małgorzata Bąkowska, Stakh Vovk
January 2, 2020 (v1)
Subject: Biosystems
Keywords: ABTS, FRAP, herbs, polyphenols, selenium
The study was performed on Centaurea cyanus, Chamomilla recutita, Majorana hortensis, Ocimum basilicum, Plantago lanceolata, Sinapis alba, and Valeriana officinalis harvested in Lithuania, Poland, and Ukraine. Our aim was to determine the differences in selenium concentrations, total polyphenols, and the antioxidant activity in same-species samples from different regions. Another goal was to assess the correlations between these variables within the species. We found variations in most species, but not in all regions of harvesting. In four of the six species from Ukraine, we observed the highest concentration of Se. The selenium concentrations ranged from 15−182 µg/kg DW, and the greatest variation between the regions occurred in S. alba. The level of polyphenols was 5.52−53.25 mg TAE/100 g DW, and the largest differences between the sampling regions occurred in P. lanceolata and O. basilicum. ABTS radicals scavenging ability ranged from 5.20−59.79 μM AAE/100 g DW, while the FRAP poten... [more]
Application of an In Vitro Psoriatic Skin Model to Study Cutaneous Metabolization of Tazarotene
Alexandre Morin, Mélissa Simard, Geneviève Rioux, Alexe Grenier, Sophie Morin, Roxane Pouliot
January 2, 2020 (v1)
Subject: Biosystems
Keywords: 3D culture, metabolization, psoriasis, skin substitutes, tazarotene, tissue engineering
Psoriasis is an inflammatory skin disease characterized by the presence of whitish and scaly plaques, which can cover up to 90% of the body surface. These plaques result from the hyperproliferation and abnormal differentiation of keratinocytes. Dermopharmaceutical testing of new therapies is limited by healthy and pathological skin models, which are not closely enough mimicking their in vivo counterparts. In this study, we exploited percutaneous absorption and Ultra Performance Liquid Chromatography (UPLC) analyses in order to determine the metabolic capacity of our psoriatic skin model. Skin substitutes were reconstructed according to the self-assembly method and tested regarding their percutaneous absorption of a topical formulation of tazarotene, followed by UPLC analyses. Histological and immunofluorescence analyses confirmed both the healthy and psoriatic phenotypes. Results from percutaneous absorption showed a significant level of tazarotene metabolite (tazarotenic acid) when th... [more]
Assessment of the Toxicity of Natural Oils from Mentha piperita, Pinus roxburghii, and Rosa spp. Against Three Stored Product Insects
Marwa I. Mackled, Mervat EL-Hefny, May Bin-Jumah, Trandil F. Wahba, Ahmed A. Allam
December 16, 2019 (v1)
Subject: Biosystems
Keywords: bioassay, contact film, fumigation, GC-MS analysis, Mentha piperita, natural plant oils, Pinus roxburghii, Rosa spp., stored product insects
Three natural oils extracted from Mentha piperita, Pinus roxburghii, and Rosa spp. were assessed in order to determine their insecticidal activity against the adults of three stored product insects: the rice weevil (Sitophilus oryzae L.), the lesser grain borer (Rhyzopertha dominica, Fabricius), and the red flour beetle (Tribolium castaneum, Herbst.). By Gas chromatography−mass spectrometry (GC/MS) analysis, the main compounds in the n-hexane oil from Rosa spp. were determined to be methyl eugenol (52.17%), phenylethyl alcohol (29.92%), diphenyl ether (7.75%), and geraniol (5.72%); in the essential oil from M. piperita, they were menthone (20.18%), 1,8-cineole (15.48%), menthyl acetate (13.13%), caryophyllene (4.82%), β-pinene (4.37%), and D-limonene (2.81%); and from the foliage of P. roxburghii, they were longifolene (19.52%), caryophyllene (9.45%), Δ-3-carene (7.01%), α-terpineol (6.75%), and γ-elemene (3.88%). S. oryzae and R. dominica were reared using sterilized wheat grains, and... [more]
Green Synthesized Silver Nanoparticles of Myrtus communis L (AgMC) Extract Inhibits Cancer Hallmarks via Targeting Aldose Reductase (AR) and Associated Signaling Network
Abdulwahab Ali Abuderman, Rabbani Syed, Abdullah A. Alyousef, Mohammed S. Alqahtani, Mohammad Shamsul Ola, Abdul Malik
December 16, 2019 (v1)
Subject: Biosystems
Keywords: anti-cancer, green synthesis, Myrtus communis L., silver NPs
In this current study, we demonstrated the green synthesis and characterization of silver nanoparticles using Myrtus communis L. plant extract (Ag-MC) and its evaluation of anticancer and antimicrobial activities. The green synthesis of (Ag-MC), was assessed by numerous characterization techniques such as ultraviolet-visible spectroscopy (UV-VIS), Fourier-transform infrared spectroscopy (FT-IR), X-ray powder diffraction (XRD) transmission electron microscopy (TEM) and energy dispersive x-ray spectroscopy (EDX). The anti-cancer activity of the green synthesized silver nanoparticles was evaluated by the median inhibitory dose (IC50) on human liver carcinoma cell lines (HepG2). These results suggested that SN-NPs can be used as effective anticancer cell lines, as well as antibacterial and antiseptic agents in the medical field. This study showed that overexpression of aldose reductase (AR) in the human liver carcinoma cell line, HepG2, was down regulated by administration of SN-MC. The do... [more]
Inhibition of Key Enzymes Linked to Obesity and Cytotoxic Activities of Whole Plant Extracts of Vernonia mesplilfolia Less
Jeremiah Oshiomame Unuofin, Gloria Aderonke Otunola, Anthony Jide Afolayan
December 16, 2019 (v1)
Subject: Biosystems
Keywords: HeLa, Hoechst 33342/PI staining, lipase, Vernonia mespilifolia, α-amylase, α-glucosidase
The whole plant of Vernonia mespilifolia is widely used as a traditional remedy for obesity in South Africa. The aim of this study was to investigate the anti-obesity and cytotoxic effects of Vernonia mespilifolia extracts in vitro. The α-amylase, α-glucosidase, and lipase inhibitory activities of aqueous and ethanol extracts of Vernonia mespilifolia were investigated, while the cytotoxic effects of these extracts were analyzed using Hoechst 33342 and propidium iodide (PI) dual staining on a human cervical HeLa cell line. The results showed that the LC50 (the concentration of a material will kill 50% of test organisms) values of aqueous and ethanol extracts of Vernonia mespilifolia were >200 and 149 µg/mL, respectively, to HeLa cells. Additionally, the ethanol extract exhibited the strongest inhibitory effect on the pancreatic lipase (Half-maximal inhibitory concentration (IC50) = 331.16 µg/mL) and on α-amylase (IC50 = 781.72 µg/mL), while the aqueous extract has the strongest α-glucos... [more]
Screening and Diversity Analysis of Aerobic Denitrifying Phosphate Accumulating Bacteria Cultivated from A2O Activated Sludge
Yong Li, Siyuan Zhao, Jiejie Zhang, Yang He, Jianqiang Zhang, Rong Ge
December 16, 2019 (v1)
Subject: Biosystems
Keywords: aerobic denitrifying phosphate accumulating bacteria (ADPB), denitrifying phosphorus removal, diversity
The aerobic denitrifying phosphate accumulating bacteria (ADPB) use NO3− as an electron acceptor and remove nitrate by denitrification and concomitant uptake of excessive phosphorus in aerobic conditions. Activated sludge was collected from the A2O aerobic biological pool of the sewage treatment plant at Hezuo Town, Chengdu City. The candidate ADPB strains were obtained by cultivation in the enriched denitrification media, followed by repeated isolation and purification on bromothymol blue (BTB) solid plates. The obtained candidates were further screened for ADPB strains by phosphorus uptake experiment, nitrate reduction test, metachromatic granules staining, and poly-β-hydroxybutyrate (PHB) staining. The 16 sedimentation ribosome deoxyribonucleic acid (16 S rDNA) molecular technique was used to determine their taxonomy. Further, the denitrification and dephosphorization capacities of ADPB strains were ascertained through their growth characteristics in nitrogen-phosphorus-rich liquid... [more]
Drug Leaching Properties of Vancomycin Loaded Mesoporous Hydroxyapatite as Bone Substitutes
Jayasingh Anita Lett, Suresh Sagadevan, Joseph Joyce Prabhakar, Nor Aliya Hamizi, Irfan Anjum Badruddin, Mohd Rafie Johan, Ab Rahman Marlinda, Yasmin Abdul Wahab, Tatagar Mohammad Yunus Khan, Sarfaraz Kamangar
December 16, 2019 (v1)
Subject: Biosystems
Keywords: drug delivery, fatty acid, Hydroxyapatite, Sol-Gel synthesis, Vancomycin
Infections after bone reconstructive surgery become an authentic therapeutic and economic issue when it comes to a modern health care system. In general; infected bone defects are regarded as contraindications for bone grafting. Since the pathogens develop a biofilm on the inner surface of the bone; local delivery of antibiotics becomes more important. The present work focuses on the synthesis of Mesoporous Hydroxyapatite (MPHAP) loaded with drug Vancomycin (Van) and to investigate its loading and leaching ability in phosphate buffer solution (PBS), to be used for post-operative infections. The effect of pore size on MPHAP was analyzed using different fatty acids as organic modifiers. The impacts of various fatty acids chain length on the morphology and pore size were studied. A simple impregnation technique with optimized conditions ensured a high antibiotic loading (up to 0.476 + 0.0135 mg/mL), with a complete in vitro release obtained within 50 h.
Essential and Recovery Oils from Matricaria chamomilla Flowers as Environmentally Friendly Fungicides Against Four Fungi Isolated from Cultural Heritage Objects
Mervat EL-Hefny, Wael A.A. Abo Elgat, Asma A. Al-Huqail, Hayssam M. Ali
December 16, 2019 (v1)
Subject: Biosystems
Keywords: antifungal activity, chamazulene, cultural heritage, flower oils, GC/MS-analysis, Matricaria chamomilla
Recovery oils, obtained from the hydro-distillation of the fresh flowers of Matricaria chamomilla, as well as essential oils, were studied for their environmental purposes in cultural heritage. These oils were assayed for their antifungal activity against the growth of four molds isolated from archaeological manuscripts (Aspergillus niger), museum gypsum board Antique (A. flavus), museum archaeological tissue (A. terreus), and museum organic materials (Fusarium culmorum) of cultural heritage objects. Oils were applied to inhibit the growth of fungi at amounts of 25, 50, 75 and, 100 µL/mL, and compared with negative controls (0 µL/mL) or positive controls (Sertaconazol 3g/L). Using GC/MS analysis, the main chemical compounds identified in the essential oil were (Z)-β-farnesene (27%), D-limonene (15.25%), and α-bisabolol oxide A (14.9%), while the compounds identified in the recovery oil were α-bisabolol oxide A (18.6%), d-limonene (8.82%), and α-bisabolol oxide B (7.13%). A low amount o... [more]
Multivariate Analysis of Plasma Metabolites in Children with Autism Spectrum Disorder and Gastrointestinal Symptoms Before and After Microbiota Transfer Therapy
James B. Adams, Troy Vargason, Dae-Wook Kang, Rosa Krajmalnik-Brown, Juergen Hahn
December 16, 2019 (v1)
Subject: Biosystems
Keywords: autism spectrum disorder, biomarker, co-occurring conditions, fecal microbiota transplant, Fisher discriminant analysis, gastrointestinal symptoms, leave-one-out cross-validation, Multivariate Statistics, plasma metabolites
Current diagnosis of autism spectrum disorder (ASD) is based on assessment of behavioral symptoms, although there is strong evidence that ASD affects multiple organ systems including the gastrointestinal (GI) tract. This study used Fisher discriminant analysis (FDA) to evaluate plasma metabolites from 18 children with ASD and chronic GI problems (ASD + GI cohort) and 20 typically developing (TD) children without GI problems (TD − GI cohort). Using three plasma metabolites that may represent three general groups of metabolic abnormalities, it was possible to distinguish the ASD + GI cohort from the TD − GI cohort with 94% sensitivity and 100% specificity after leave-one-out cross-validation. After the ASD + GI participants underwent Microbiota Transfer Therapy with significant improvement in GI and ASD-related symptoms, their metabolic profiles shifted significantly to become more similar to the TD − GI group, indicating potential utility of this combination of plasma metabolites as a b... [more]
Simultaneous Removal of Calconcarboxylic Acid, NH4+ and PO43− from Pharmaceutical Effluent Using Iron Oxide-Biochar Nanocomposite Loaded with Pseudomonas putida
Saifeldin M. Siddeeg, Mohamed A. Tahoon, Faouzi Ben Rebah
December 16, 2019 (v1)
Subject: Biosystems
Keywords: biochar, calconcarboxylic acid, industrial wastewater, microorganisms, nanocomposites
In the current study, the Fe2O3/biochar nanocomposite was synthesized through a self-assembly method, followed by the immobilization of Pseudomonas putida (P. putida) on its surface to produce the P. putida/Fe2O3/biochar magnetic innovative nanocomposite. The synthesized nanocomposite was characterized using different techniques including X-ray diffraction, transmission electron microscopy (TEM), scanning electron microscopy (SEM), and Fourier-transform infrared spectroscopy (FT-IR). Then, the efficiencies of this material to remove calconcarboxylic acid (CCA) organic dye, ammonium ions (NH4+), and phosphate ions (PO43−) from industrial wastewater were analyzed. The removal rates of up to 82%, 95%, and 85% were achieved for CCA dye, PO43−, NH4+, respectively, by the synthesized composite. Interestingly, even after 5 cycles of reuse, the prepared nanocomposite remains efficient in the removal of pollutants. Therefore, the P. putida/Fe3O4/biochar composite was found to be an actual talen... [more]
Integrated Bioethanol Fermentation/Anaerobic Digestion for Valorization of Sugar Beet Pulp
Joanna Berlowska, Katarzyna Pielech-Przybylska, Maria Balcerek, Weronika Cieciura, Sebastian Borowski, Dorota Kregiel
December 10, 2019 (v1)
Subject: Biosystems
Keywords: bioethanol, Hydrogen, hydrolysis, methane, stillage, sugar beet pulp
Large amounts of waste biomass are generated in sugar factories from the processing of sugar beets. After diffusion with hot water to draw the sugar from the beet pieces, a wet material remains called pulp. In this study, waste sugar beet pulp biomass was enzymatically depolymerized, and the obtained hydrolyzates were subjected to fermentation processes. Bioethanol, biomethane, and biohydrogen were produced directly from the substrate or in combined mode. Stillage, a distillery by-product, was used as a feedstock for anaerobic digestion. During biosynthesis of ethanol, most of the carbohydrates released from the sugar beet pulp were utilized by a co-culture of Saccharomyces cerevisiae Ethanol Red, and Scheffersomyces stipitis LOCK0047 giving 12.6 g/L of ethanol. Stillage containing unfermented sugars (mainly arabinose, galactose and raffinose) was found to be a good substrate for methane production (444 dm³ CH₄/kg volatile solids (VS)). Better results were achieved with this medium tha... [more]
Predicting the Longitudinally and Radially Varying Gut Microbiota Composition using Multi-Scale Microbial Metabolic Modeling
Siu H. J. Chan, Elliot S. Friedman, Gary D. Wu, Costas D. Maranas
December 10, 2019 (v1)
Subject: Biosystems
Keywords: genome-scale metabolic model, gut microbiome, multi-scale modeling, spatial heterogeneity
Background: The gut microbiota is a heterogeneous group of microbes that is spatially distributed along various sections of the intestines and across the mucosa and lumen in each section. Understanding the dynamics between the spatially differential microbial populations and the driving forces for the observed spatial organization will provide valuable insights into important questions such as the nature of colonization of the infant gut and different types of inflammatory bowel disease localized in different regions of the intestines. However, in most studies, the microbiota is sampled only at a single site (often feces) or from a particular anatomical site of the intestines. Differential oxygen availability is putatively a key factor shaping the spatial organization. Results: To test this hypothesis, we constructed a community genome-scale metabolic model consisting of representative organisms for the major phyla present in the human gut microbiome. By solving step-wise optimization... [more]
Detoxification of a Lignocellulosic Waste from a Pulp Mill to Enhance Its Fermentation Prospects
Tamara Llano, Natalia Quijorna, Alberto Coz
December 10, 2019 (v1)
Subject: Biosystems
Keywords: biorefinery, detoxification, Fermentation, inhibitors, spent sulfite liquor, sugars
Detoxification is required for sugar bioconversion and hydrolyzate valorization within the biorefining concept for biofuel or bio-product production. In this work, the spent sulfite liquor, which is the main residue provided from a pulp mill, has been detoxified. Evaporation, overliming, ionic exchange resins, and adsorption with activated carbon or black carbon were considered to separate the sugars from the inhibitors in the lignocellulosic residue. Effectiveness in terms of total and individual inhibitor removals, sugar losses and sugar-to-inhibitor removal ratio was determined. The best results were found using the cation exchange Dowex 50WX2 resin in series with the anion exchange Amberlite IRA-96 resin, which resulted in sugar losses of 24.2% with inhibitor removal of 71.3% of lignosulfonates, 84.8% of phenolics, 82.2% acetic acid, and 100% of furfurals. Apart from exchange resins, the results of evaporation, overliming, adsorption with activated carbon and adsorption with black... [more]
Effects of Biogas Substrate Recirculation on Methane Yield and Efficiency of a Liquid-Manure-Based Biogas Plant
Frauke P. C. Müller, Gerd-Christian Maack, Wolfgang Buescher
December 10, 2019 (v1)
Subject: Biosystems
Keywords: biogas, hydraulic retention time (HRT), methane output, organic loading rate (OLR), recirculation
Biogas plants are the most complex systems and are heavily studied in the field of renewable energy. A biogas system is mainly influenced by biological and technical parameters that strongly interact with each other. One recommended practice when operating a biogas plant is the recirculation of the substrate from the second fermenter into the first fermenter, which extends the recirculation amount (RA) and, in turn, the recirculation rate (RR). This technique should be applied to support and secure the biogas process. In this investigation, the RA was varied, starting with the recommended “best practice” of 10.0 m³/d (RR 40%). Every ten days, the RA was reduced in steps of 1.5 m³/d, with 5.5 m³/d (RR 27%) being the final value. The basic question to be addressed concerns to what extent the RR influences the methane yield and thereby influence the efficiency of a manure-based biogas plant in practice. Diverting the “best practice” to a RR of 27% stabilised the fermentation process and l... [more]
High-Titer Methane from Organosolv-Pretreated Spruce and Birch
Leonidas Matsakas, Christos Nitsos, Dimitrij Vörös, Ulrika Rova, Paul Christakopoulos
December 10, 2019 (v1)
Subject: Biosystems
Keywords: anaerobic digestion, biogas, birch, lignocellulosic biomass, methane, organosolv pretreatment, spruce
The negative impact of fossil fuels and the increased demand for renewable energy sources has led to the use of novel raw material sources. Lignocellulosic biomass could serve as a possible raw material for anaerobic digestion and production of biogas. This work is aimed at using forest biomass, both softwood (spruce) and hardwood (birch), as a raw material for anaerobic digestion. We examined the effect of different operational conditions for the organosolv pretreatment (ethanol content, duration of treatment, and addition of acid catalyst) on the methane yield. In addition, we investigated the effect of addition of cellulolytic enzymes during the digestion. We found that inclusion of an acid catalyst during organosolv pretreatment improved the yields from spruce, but it did not affect the yields from birch. Shorter duration of treatment was advantageous with both materials. Methane yields from spruce were higher with lower ethanol content whereas higher ethanol content was more benef... [more]
LC-ESI-QTOF/MS Profiling of Australian Mango Peel By-Product Polyphenols and Their Potential Antioxidant Activities
Danying Peng, Hafza Fasiha Zahid, Said Ajlouni, Frank R. Dunshea, Hafiz A. R. Suleria
December 10, 2019 (v1)
Subject: Biosystems
Keywords: antioxidant activity, HPLC-PDA, LC-ESI-QTOF/MS, mango peels, polyphenols
Mango (Mangifera indica L.) is one of the most important fruits in the world. Mango peel is an important by-product that is rich in polyphenols and it could have high economic value if it is effectively utilized. Phenolic characterization is an essential step in the commercial utilization of mango peel by-products as food ingredients. Herein, qualitative and quantitative analyses of two Australian mango peel “Keitt” and “Kensington Pride” (K&P) by-products were conducted while using liquid chromatography coupled to electrospray ionisation and quadrupole time of flight mass spectrometry (LC-ESI-QTOF/MS) and high-performance liquid chromatography coupled to photodiode array detector (HPLC-PDA). A total of 98 polyphenols compounds were tentatively identified in both Keitt peel and K&P peel extracts, with greater concentrations of these compounds being detected in Keitt peel. The total phenolic content (TPC), total flavonoid content (TFC), and a total tannin content (TTC) were determined.... [more]
Effect of Enzyme Interaction with Lignin Isolated from Pretreated Miscanthus × giganteus on Cellulolytic Efficiency
Woochul Jung, Ratna Sharma-Shivappa, Praveen Kolar
December 10, 2019 (v1)
Subject: Biosystems
Keywords: hydrolysis, inhibition, lignin, miscanthus, pretreatment
The effect of binding between the lignin isolates from an alkali (NaOH)− and an acid (H2SO4)− pretreated Miscanthus and cellulolytic enzymes in Cellic® CTec2 was investigated. Additonally, cellobiose and Avicel were enzymatically hydrolyzed with and without lignin isolates to study how enzyme binding onto lignin affects its conversion to glucose. Three carbohydrate−lignin loadings (0.5:0.25, 0.5:0.5, and 0.5:1.0% (w/v)) were employed. The results indicated that β-glucosidase (BG) had a strong tendency to bind to all lignin isolates. The overall tendency of enzyme binding onto lignin isolate was similar regardless of pretreatment chemical concentration. Though enzyme binding onto lignin isolates was observed, hydrolysis in the presence of these isolates did not have a significant (p > 0.05) impact on glucose production from cellobiose and Avicel. Cellobiose to glucose conversion of 99% was achieved via hydrolysis at both 5 and 10 FPU/g carbohydrate. Hydrolysis of Avicel with 5 and 10 FP... [more]
Ultrasound-Assisted Phytochemical Extraction Condition Optimization Using Response Surface Methodology from Perlette Grapes (Vitis vinifera)
Muhammad Kaleem, Asif Ahmad, Rai Muhammad Amir, Ghazala Kaukab Raja
December 10, 2019 (v1)
Subject: Biosystems
Keywords: antioxidants, flavonoids, phytochemicals, ultrasound, Vitis vinifera
In the current study, bioactive compounds of Vitis vinifera (Perlette) were extracted using an ultrasound-assisted extraction technique. The central composite design of response surface methodology (RSM) was used to determine the effect of time, temperature, and concentration of acetic acid on response variables that include extract yield, total phenolic content (TPC), total flavonoid content (TFC), and antioxidant activity of Vitis vinifera extracts. The results of the central composite design of RSM revealed that the quadratic polynomial model is best fitted to experimental results, with all the responses having a regression coefficient greater than 0.9. Optimized extraction levels include 26.5 min, an extraction temperature of 59 °C, and an acetic acid concentration of 62.9% with good extraction yield results of 34.95 g/100 g dry weight (DW) of grapes, TPC 34.38 mg gallic acid equivalent per gram (GAE/g) DW, flavonoid content 10.21 mg quercetin equivalents per gram (QEQ/g) DW, and a... [more]
Stimuli-Sensitive Cell Penetrating Peptide-Modified Nanocarriers
Federico Perche
December 10, 2019 (v1)
Subject: Biosystems
Keywords: cellular uptake, peptides, responsive
The integration of drugs into nanocarriers favorably altered their pharmacodynamics and pharmacokinetics compared to free drugs, and increased their therapeutic index. However, selective cellular internalization in diseased tissues rather than normal tissues still presents a formidable challenge. In this chapter I will cover solutions involving environment-responsive cell-penetrating peptides (CPPs). I will discuss properties of CPPs as universal cellular uptake enhancers, and the modifications imparted to CPP-modified nanocarriers to confine CPP activation to diseased tissues.
Production Process and Optimization of Solid Bioethanol from Empty Fruit Bunches of Palm Oil Using Response Surface Methodology
Nurfahmi, M. Mofijur, Hwai Chyuan Ong, Badrul Mohamed Jan, Fitranto Kusumo, Abdi Hanra Sebayang, Hazlina Husin, Arridina Susan Silitonga, Teuku Meurah Indra Mahlia, S. M. Ashrafur Rahman
December 10, 2019 (v1)
Subject: Biosystems
Keywords: bioethanol production, calorific value, enzyme hydrolysis, organosolv pretreatment, response surface methodology, solid bioethanol
This study aimed to observe the potential of solid bioethanol as an alternative fuel with high caloric value. The solid bioethanol was produced from liquid bioethanol, which was obtained from the synthesis of oil palm empty fruit bunches (PEFBs) through the delignification process by using organosolv pretreatment and enzymatic hydrolysis. Enzymatic hydrolysis was conducted using enzyme (60 FPUg−1 of cellulose) at a variety of temperatures (35 °C, 70 °C, and 90 °C) and reaction times (2, 6, 12, 18, and 24 h) in order to obtain a high sugar yield. The highest sugars were yielded at the temperature of 90 °C for 48 h (152.51 mg/L). Furthermore, fermentation was conducted using Saccharomyces cerevisiae. The bioethanol yield after fermentation was 62.29 mg/L. Bioethanol was extracted by distillation process to obtain solid bioethanol. The solid bioethanol was produced by using stearic acid as the additive. In order to get high-quality solid bioethanol, the calorific value was optimized using... [more]
Showing records 1089 to 1113 of 1288. [First] Page: 1 41 42 43 44 45 46 47 48 49 Last
(0.09 seconds)
[Show All Subjects]

[0.11 s]