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Records with Subject: Biosystems
Showing records 51 to 75 of 1278. [First] Page: 1 2 3 4 5 6 7 Last
Optimizing the Salt-Processing Parameters of Achyranthes bidentata and Their Correlation with Anti-Osteoarthritis Effect
Jieqiang Zhu, Lisha Shen, Guofang Shen, Yi Tao
June 6, 2024 (v1)
Subject: Biosystems
Keywords: Achyranthes bidentata, anti-inflammatory, cyclooxygenase-2, salt-processing
is always salt-processed before being prescribed for treating osteoarthritis. Yet the salt-processing parameters have not been optimized, and the specific bioactive constituents responsible for the osteoarthritis effect of salt-processed A. bidentata have not been fully elucidated. In this study, a Box−Behnken experimental design was chosen for the optimization of the salt-processing parameters of A. bidentata, including stir-frying time, concentration of brine, and soak time. Meanwhile, HPLC−Q-TOF-MS was utilized to analyze the chemical profiles of various batches of raw and salt-processed A. bidentata. The anti-inflammatory potential of nine batches of both raw and salt-processed A. bidentata was assessed via a cyclooxygenase-2 (COX-2) inhibitory assay. A gray correlation analysis was conducted to correlate the peak areas of the compounds in raw and salt-processed A. bidentata with their COX-2 inhibitory effects. Finally, the optimal salt-processing conditions are as follows: soak ti... [more]
Comparison between Conventional Ageing Process in Barrels and a New Rapid Aging Process Based on RSLDE: Analysis of Bioactive Compounds in Spirit Drinks
Daniele Naviglio, Paolo Trucillo, Angela Perrone, Domenico Montesano, Monica Gallo
June 6, 2024 (v1)
Subject: Biosystems
Keywords: aged beverages, alcoholic beverages, bioactive compounds, chips, distillates, grappa, maceration, RSLDE
“Aging” is a practice that allows alcoholic beverages to mature and gives them particular flavors and colors. In this context, oak or durmast wooden barrels are used in this process, thus providing different types of aging. This conventional process produces a slow enrichment of organic compounds in the spirit inside the barrels. Organic substances present in the internal part of the barrels slowly undergo the phenomenon of extraction by the liquid phase (solid−liquid extraction). In this work, a new procedure based on rapid solid−liquid dynamic extraction (RSLDE) was used to evaluate the potential of obtaining the effects of aging in spirits in shorter times than conventional methods. For this purpose, a comparison between two solid−liquid extraction techniques, RSLDE and conventional maceration, was made. Four water/ethanol 60:40 (v/v) model solutions were prepared and put in contact with medium-toasted chips using the two extraction procedures (conventional and non-conventional) and... [more]
Scaling Fed-Batch and Perfusion Antibody Production Processes in Geometrically Dissimilar Stirred Bioreactors
Vivian Ott, Jan Ott, Dieter Eibl, Regine Eibl
June 6, 2024 (v1)
Subject: Biosystems
Keywords: automation, Chinese hamster ovary cells, monoclonal antibodies, perfusion, Process Intensification, upstream process
Modern production processes for biopharmaceuticals often work with very high cell densities. Moreover, there is a trend towards moving from fed-batch to continuous perfusion processes; a development that is influencing the requirements for bioreactor design and process control. In this study, the transfer of fed-batch and perfusion experiments between different cylindrical stirred lab-scale bioreactors and Thermo Scientific’sTM (Waltham, MA, USA) cubical HyPerformaTM DynaDriveTM Single-Use Bioreactor was investigated. Different scaling parameters were used, which were selected based on the requirements of the respective processes. Peak cell densities of up to 49 × 106 cells mL−1 and antibody titers of up to 5.2 g L−1 were achieved in 15- to 16-day fed-batch experiments. In 50-day perfusion cultivations, a viable cell volume of >100 mm3 mL−1 was maintained and more than 1 g L−1 d−1 of antibodies were harvested. The perfusion processes were automated with both cell bleed control and gluc... [more]
Antifungal Capacity of Microcapsules Containing Lactiplantibacillus plantarum TEP15 or Lactiplantibacillus pentosus TEJ4
Yeni Pérez-Ruiz, David Mejía-Reyes, Raymundo Rosas-Quijano, Didiana Gálvez-López, Miguel Salvador-Figueroa, Alfredo Vázquez-Ovando
June 5, 2024 (v1)
Subject: Biosystems
Keywords: biocontrol, extrusion, gum arabic, lactic acid bacteria, phytopathogenic fungi, sodium alginate, whey protein
The use of lactic acid bacteria (LAB) for the biocontrol of fungi that cause fruit and vegetable deterioration is a highly promising strategy. However, one of the main challenges lies in maintaining both viability and antifungal activity even in conditions that are unfavorable for LAB. The microencapsulation of LAB can minimize the impact of environmental conditions, helping to maintain viability, but there is still little information on what occurs with respect to antifungal activity. Therefore, the objective of this study was to evaluate the effect of microencapsulation with several polymer blends on the viability and antifungal activity of Lactiplantibacillus plantarum TEP15 and L. pentosus TEJ4. Sodium alginate (2%), sodium alginate−gum arabic (2%:1%), sodium alginate−k-carrageenan (2%:0.05%), and sodium alginate−whey protein (0.75%:1.5%) were used as encapsulating polymers. After processing (day 0), as well as after 14 and 28 days of storage, the encapsulation efficiency, moisture... [more]
Pyrene-Modified Cyclic Peptides Detect Cu2+ Ions by Fluorescence in Water
Yuhi Maekawa, Sora Sakura, Yuji Furutani, Rento Fujihara, Hisashi Sugime, Takashi Ohtsuki, Mizuki Kitamatsu
June 5, 2024 (v1)
Subject: Biosystems
Keywords: fluorescence, metal ion, peptide, pyrene
The detection of metal ions is an option for maintaining water quality and diagnosing metal ion-related diseases. In this study, we successfully detected metal ions using fluorescent peptides in water. First, we prepared seven linear (L1−L7) and seven cyclic (C1−C7) peptides containing two pyrenyl (Pyr) units and assessed the response to various metal ions by fluorescence. The results indicated that C1, which contains a hexameric cyclic peptide moiety consisting of Pyr and Gly units, did not show a fluorescent response to metal ions, while the linear L1 corresponding to C1 showed a response to Cu2+, but its selectivity was found to be poor through a competition assay for each metal ion. We then assessed C2−C7 and L2−L7, in which Gly was replaced by His units at various positions in the same manner. The results showed that C2−C7 responded to Cu2+ in a manner dependent on the His position. Additionally, superior selectivity was observed in C7 through a competition assay. These results de... [more]
Studies on Reactive Extraction of Itaconic Acid from Fermentation Broths
Alexandra Cristina Blaga, Lenuta Kloetzer, Dan Cascaval, Anca-Irina Galaction, Alexandra Tucaliuc
June 5, 2024 (v1)
Subject: Biosystems
Keywords: Aspergillus terreus, fermentation broths, itaconic acid, reactive extraction, tri-n-octylamine
Itaconic acid is a high-value organic acid that serves as a platform molecule in different industries. This research focuses on the separation of itaconic acid using reactive extraction as a sustainable and efficient method for acid recovery from fermentation broth. Itaconic acid was produced through fungal fermentation processes involving Aspergillus terreus ATCC® 32588™, obtaining a concentration of 47 g/L in the final broths. For the reactive extraction system, the organic phase included tri-n-octylamine as an extractant dissolved in dichloromethane or n-heptane and 1-octanol as a phase modifier. The effect of the main influencing factors (pH of the aqueous phase, extractant concentrations in the organic phase, and the addition of 1-octanol) on extraction efficiency was investigated. The highest extraction degree (97%) was achieved using an organic phase with tri-n-octylamine dissolved in dichloromethane and with 20% 1-octanol. Conversely, in the reactive extraction system with tri-... [more]
Sustainable Electricity Production Using Avocado Waste
Segundo Rojas-Flores, Juan Vives-Garnique, Félix Díaz, Magaly De La Cruz-Noriega
June 5, 2024 (v1)
Subject: Biosystems
Keywords: avocado, bioenergy, microbial fuel cell, organic waste
Agroindustry waste has exponentially increased in recent years, generating economic losses and environmental problems. In addition, new ways to generate sustainable alternative electrical energy are currently being sought to satisfy energy demand. This investigation proposes using avocado waste as fuel for electricity generation in single-chamber MFCs. The avocado waste initially operated with an ambient temperature (22.4 ± 0.01 °C), DO of 2.54 ± 0.01 mg/L, TDS of 1358 ± 1 mg/L and COD of 1487.25 ± 0.01 mg/L. This research managed to generate its maximum voltage (0.861 ± 0.241 V) and current (3.781 ± 0.667 mA) on the fourteenth day, operating at an optimal pH of 7.386 ± 0.147, all with 126.032 ± 8.888 mS/cm of electrical conductivity in the substrate. An internal resistance of 67.683 ± 2.456 Ω was found on day 14 with a PD of 365.16 ± 9.88 mW/cm2 for a CD of 5.744 A/cm2. Micrographs show the formation of porous biofilms on both the anodic and cathodic electrodes. This study gives preli... [more]
Sodium Alginate−Soy Protein Isolate−Chitosan−Capsaicin−Nanosilver Multifunctional Antibacterial Composite Gel
Zhichao Zhang, Meizi Huang, Kejian Shen, Yucai He, Youyan Liu
June 5, 2024 (v1)
Subject: Biosystems
Keywords: antibacterial ability, dye adsorption, microbial pollution, milk preservation, nanosilver antibacterial composite
We constructed a sodium alginate/soy protein isolate/chitosan gel system and incorporated silver nanoparticles reduced by capsaicin into the system, forming a sodium alginate−soy protein isolate−chitosan−capsaicin−silver nanoparticle composite gel (SA/SPI/CTS/CAP/Ag). In tests, the SA/SPI/CTS/CAP/Ag gel exhibited excellent antimicrobial properties. Using the agar diffusion method, the inhibition zone diameter for Staphylococcus aureus was determined to be 29.5 mm. Soy protein isolate (SPI), containing a large number of hydrophobic amino acid residues, effectively enhanced the moisture retention capability of the gel and improved its stability to a certain extent at an appropriate addition concentration. In a milk preservation experiment, the SA/SPI/CTS/CAP/Ag gel significantly extended the shelf-life of the milk. In dye adsorption experiments, the adsorption curve of the SA/SPI/CTS/CAP/Ag gel well fitted a pseudo-second-order kinetic model. It showed a degree of adsorption capacity for... [more]
Analyzing the Effect of Extraction Parameters on Phenolic Composition and Selected Compounds in Clove Buds Using Choline Chloride and Lactic Acid as Extraction Agents
Petra Strižincová, Igor Šurina, Michal Jablonský, Veronika Majová, Aleš Ház, Katarína Hroboňová, Andrea Špačková
June 5, 2024 (v1)
Subject: Biosystems
Keywords: choline chloride, clove buds, design of experiment, eugenol, Extraction, lactic acid
Utilizing a deep eutectic solvent-like mixture such as choline chloride and lactic acid in a 1:2 molar ratio, clove buds underwent extraction. Furthermore, the determination of the primary components in the clove extracts, namely eugenol, eugenol acetate, and β-caryophyllene, was conducted using the HPLC-DAD method. The total phenolic content (TPC) was also established. Extraction conditions using choline chloride and lactic acid encompassed variables such as extraction temperature (within the range of 40 to 80 °C), water addition (ranging from 5.6 to 40%), and extraction time (ranging from 30 to 90 min). Optimal operational conditions for TPC were pinpointed at 77 °C, 30 min, and a water addition of 40%. The findings showed that clove extracts obtained at 60 °C, 22.8%, and 30 min had the highest amount of eugenol (307.26 ± 8.44 mg/g dry raw material).
The Use of Immobilised Enzymes for Lipid and Dairy Processing and Their Waste Products: A Review of Current Progress
Fawzih Alzahrani, Taiwo O. Akanbi, Christopher J. Scarlett, Alberta N. A. Aryee
June 5, 2024 (v1)
Subject: Biosystems
Keywords: activity, applications, enzymes, immobilisation, processing
The use of edible oils and fats in dairy products is becoming increasingly important in the food industry because of their complementary functional properties. Most of these products are produced using food-grade enzymes as processing aids because processes involving enzymes are considered mild and environmentally friendly for regulatory purposes. The poor stability and recovery of enzymes in their native state limit their performance, and to enhance their activity, stability, and reusability, enzymes are often immobilised—a process that involves attaching them to a solid support. Additionally, immobilisation enables enzymes to selectively target specific substrates or products, making them highly efficient. These features have led to the increased use of immobilised enzymes in dairy and lipid processing and enzymes have been used to produce a broad range of products such as whey protein concentrates and isolates, peptide−lipid conjugates, lipid concentrates, structured lipids, and hum... [more]
Chemical Modification of Birch Bark (Betula L.) for the Improved Bioprocessing of Cadmium(II), Chromium(VI), and Manganese(II) from Aqueous Solutions
Jarosław Chwastowski, Paweł Staroń
June 5, 2024 (v1)
Subject: Biosystems
Keywords: bioprocessing, green chemistry, heavy metal ions, kinetics, natural sorbents
This study aimed to assess the sorption capacity of a natural sorbent, specifically birch bark (BB), and its modification using chemical reagents, including nitric and hydrochloric acid, sodium hydroxide, and chloride. The objective of the chemical modification was to enhance the sorption capacity of the heavy metals cadmium(II), chromium(VI), and manganese(II). The most effective modification for adsorbing cadmium and manganese from aqueous solutions was achieved by treating the sorbent with a 0.1 M sodium hydroxide solution (BBNa). Conversely, in the case of chromium, each modification adversely affected its adsorption by the sorbent. Concentrations of the solutions were analyzed using atomic absorption spectrometry at appropriate time intervals. The adsorption process was described using Langmuir, Freundlich, and Temkin isotherms. The Freundlich isotherm provided the best fit for cadmium and chromium (R2 = 0.988 and 0.986, respectively), while the Langmuir isotherm was most suitable... [more]
Supercritical CO2-Based Extraction and Detection of Phenolic Compounds and Saponins from the Leaves of Three Medicago varia Mart. Varieties by Tandem Mass Spectrometry
Mayya P. Razgonova, Muhammad Amjad Nawaz, Elena P. Ivanova, Elena I. Cherevach, Kirill S. Golokhvast
June 5, 2024 (v1)
Subject: Biosystems
Keywords: alfalfa changeable, Medicago varia Mart., metabolome, polyphenols, SC-CO2 extraction, tandem mass spectrometry
A comparative metabolomic study of three varieties of alfalfa (Medicago varia Mart.) was performed via extraction with supercritical carbon dioxide modified with ethanol (EtOH) and the detection of bioactive compounds via tandem mass spectrometry. Several experimental conditions were investigated in the pressure range of 50−250 bar, with ethanol used as a co-solvent in an amount of 1% of the total volume in the liquid phase at a temperature in the range of 31−70 °C. The most effective extraction conditions were as follows: a pressure of 250 Bar and a temperature of 60 °C for M. varia. M. varia contains various phenolic compounds and sulfated polyphenols with valuable biological activity. Tandem mass spectrometry (HPLC-ESI−ion trap) was applied to detect the target analytes. A total of 103 bioactive compounds (59 polyphenols and 44 compounds belonging to other chemical groups) were tentatively identified in extracts from aerial parts of alfalfa. For the first time, twenty-one chemical c... [more]
Comparative Study of the Stilbenes and Other Phenolic Compounds in Cabernet Sauvignon Wines Obtained from Two Different Vinifications: Traditional and Co-Inoculation
Aleksandar Petrović, Nikolina Živković, Ljilja Torović, Ana Bukarica, Vladan Nikolić, Jelena Cvejić, Ljiljana Gojković-Bukarica
June 5, 2024 (v1)
Subject: Biosystems
Keywords: co-inoculation, non-Saccharomyces yeast, phenolic compounds, quercetin, Torulaspora delbrueckii, trans-resveratrol
From grape cultivation to ripening and harvest timing to processing, each step of the winemaking process can be a critical point when it comes to wine quality and phenolic composition. In this study, the influence of winemaking technology on resveratrol and quercetin content, as well as other polyphenolic compounds, was investigated. Resveratrol is a non-flavonoid polyphenolic stilbene synthesized by grape skin when damaged by infectious diseases or ionizing radiation. Quercetin is a phenol found in grape skins and stems and is produced to protect grapes from UV light damage. Trans-resveratrol and quercetin are known to act as antioxidants, reduce the risk of atherosclerosis and type 2 diabetes, inhibit the growth of cancer cells, and prevent the release of allergic and inflammatory molecules. However, the question was whether red wine could be enriched with these phenols using a co-inoculation winemaking technology. The main new idea was to completely replace the cold maceration proce... [more]
Fungal Isolation, Detection, and Quantification of Aflatoxins in Nuts Sold in the Lebanese Market
Heba Hellany, Jean Claude Assaf, Joseph Matta, Mahmoud I. Khalil
June 5, 2024 (v1)
Subject: Biosystems
Keywords: aflatoxins, ELISA, HPLC, Lebanese nuts, toxigenic fungi
This study examines the prevalence of aflatoxin contamination in 160 nut samples, both shelled and unshelled (including pistachios, peanuts, and walnuts), from the Lebanese market, focusing on their fungal contamination and specific toxigenic strains. Aflatoxin B1 (AFB1), known for its potent carcinogenic and immunosuppressive properties, was detected in various samples. Moisture content analysis showed that unshelled nuts often exceeded maximum moisture limits more frequently than shelled nuts, with levels ranging from 1.9 to 9.5%. The predominant fungal genus identified through cultivation on potato dextrose agar (PDA) plates was Aspergillus. In total, 55% of samples were contaminated with A. flavus and 45% with A. niger. All toxigenic strains isolated were identified as Aspergillus flavus. The aflatoxins, particularly AFB1, were quantified using the enzyme-linked immunosorbent assay (ELISA) and reversed-phase high-performance liquid chromatography (HPLC), revealing contamination in... [more]
Physico-Chemical Aspects of Metal−Fulvic Complexation
Martina Klučáková, Jitka Krouská, Michal Kalina
June 5, 2024 (v1)
Subject: Biosystems
Keywords: charge, fulvic acid, interaction, metal ion, particle size, thermodynamics
The interactions of metal ions with fulvic acids were investigated from the point of view of the thermodynamic aspects of complexation as well as the size and charge of the formed complexes. Thermodynamic aspects were studied by means of isothermal titration calorimetry. Particle size distribution was determined by the method of dynamic light scattering and charge by the measurement of zeta potential. Complexation resulted in changes in particle size and charge. The particle size distribution was trimodal for fulvic acids and bimodal for fulvic complexes with calcium and magnesium, while copper−fulvic complexes had only one size fraction. The compensation of the negative charge of carboxylic and phenolic functional groups by positively charged metal ions resulted in an increase in zeta potential which became closer to zero in the case of copper−fulvic complexes. However, all metal−humic complexes behaved as colloidally unstable, which resulted in visually observable sedimentation. Calo... [more]
Comparative Analysis of Enzyme-, Ultrasound-, Mechanical-, and Chemical-Assisted Extraction of Biflavonoids from Ginkgo Leaves
Anita Šalić, Lina Šepić, Iva Turkalj, Bruno Zelić, Dunja Šamec
June 5, 2024 (v1)
Subject: Biosystems
Keywords: amentoflavone, assisted extraction, biflavonoids, bilobetin, ginkgetin, ginkgo, isoginkgetin, sciadopitysin
The biflavonoid extraction from ginkgo (Ginkgo biloba L.) leaves using solvent-based extraction with 70% ethanol, alone and in combination with enzyme-assisted, ultrasound-assisted, mechanical-assisted, and chemically assisted methods was investigated and the influence of extraction duration was explored. The total content of polyphenols, flavonoids, and phenolic acids in the extracts was determined spectrophotometrically, while individual biflavonoids were identified and quantified using HPLC-DAD. Amentoflavone, bilobetin, ginkgetin, isoginkgetin, and sciadopitysin were identified in all our extracts. Among these, sciadopitysin emerged as the most prevalent biflavonoid with an amount above 1 mg g−1 dw, followed by isoginkgetin. Comparative analysis of the extraction methods revealed that, except for chemically assisted extraction, similar levels of compounds were obtained after 45 min of extraction. However, enzymatic (EAE) and mechanical-assisted extraction (MAE) exhibited significan... [more]
Enhanced Production of Clean Fermentable Sugars by Acid Pretreatment and Enzymatic Saccharification of Sugarcane Bagasse
Mario Alberto Yaverino-Gutierrez, Lucas Ramos, Jesús Jiménez Ascencio, Anuj Kumar Chandel
June 5, 2024 (v1)
Subject: Biosystems
Keywords: detoxification, reducing sugars, saccharification, sugarcane bagasse, sugarcane hydrolysate
Sugarcane bagasse (SCB), an agro-industrial byproduct generated by a sugar mill, holds a substantial carbohydrate content of around 70 wt.%, comprising cellulose and hemicellulose. Saccharification plays a pivotal role in the conversion of SCB into second-generation (2G)-ethanol and valuable compounds, which is significantly aided by thermochemical pretreatments. In this study, SCB underwent diluted sulfuric acid pretreatment (2% H2SO4, 80 rpm, 200 °C, 20 min), resulting in the removal of 77.3% of the xylan. The hemicellulosic hydrolysate was analyzed to identify the sugars and degraded products acting as microbial inhibitors. The acid hydrolysate showed a xylose yield of 68.0% (16.4 g/L) and a yield of 3.8 g/L of acetic acid. Afterward, the hemicellulosic hydrolysate was concentrated 2.37 times to obtain a xylose-rich stream (39.87 g/L). The sequential detoxification, employing calcium oxide and activated carbon, removed the inhibitory compounds, including acetic acid, while preservin... [more]
Recent Advances in Drying Processing Technologies for Aquatic Products
Weibin Wu, Haoxin Li, Yingmei Chen, Yuanqiang Luo, Jinbin Zeng, Jingkai Huang, Ting Gao
June 5, 2024 (v1)
Subject: Biosystems
Keywords: aquatic product, drying pretreatment technology, drying quality, drying technology, non-destructive monitoring techniques
Fresh aquatic products, due to their high water activity, are susceptible to microbial contamination and spoilage, resulting in a short shelf life. Drying is a commonly used method to extend the shelf life of these products by reducing the moisture content, inhibiting microbial growth, and slowing down enzymatic and chemical reactions. However, the drying process of aquatic products involves chemical reactions such as oxidation and hydrolysis, which pose challenges in obtaining high-quality dried products. This paper provides a comprehensive review of drying processing techniques for aquatic products, including drying preprocessing, drying technologies, and non-destructive monitoring techniques, and discusses their advantages and challenges. Furthermore, the impact of the drying process on the quality attributes of dried products, including sensory quality, nutritional components, and microbial aspects, is analyzed. Finally, the challenges faced by drying processing techniques for aqua... [more]
Special Issue Entitled “Immune Regulatory Properties of Natural Products”
Jai-Eun Kim, Wansu Park
June 5, 2024 (v1)
Subject: Biosystems
Although the immunomodulatory effects of natural products have not yet been completely elucidated, attempts to use natural products in the treatment of immune-mediated inflammatory diseases such as autoimmune diseases, chronic inflammatory diseases, mutant viral infections, and even immunosenescence-related cancers are ongoing [...]
The Influence of Polyphenolic Compounds on Anaerobic Digestion of Pepper Processing Waste during Biogas and Biomethane Production
Gregor Drago Zupančič, Anamarija Lončar, Jasmina Ranilović, Drago Šubarić, Mario Panjičko
June 5, 2024 (v1)
Subject: Biosystems
Keywords: anaerobic digestion, Capsicum annuum, epicatechin, ferulic acid, myricetin, polyphenols, procyanidins, quercetin
Pepper processing waste has the potential to be used as a substrate in the process of anaerobic digestion, but because of its high polyphenol content, certain limitations are expected. During the determination of the biodegradability of pepper samples, a biogas potential of 687 L/kg DM was observed, as well as a biomethane potential of 401 L/kg DM. While both the testing of biodegradability and the process in the pilot scale progressed, it was observed that total polyphenol content in both cases decreased. Also, as far as individual polyphenols during the process in the pilot scale are concerned, it can be observed that at the end of the process no procyanidin A2, epicatechin, myricetin, and quercetin were detected. The observed concentration of the ferulic acid on the last day of the process was 0.09 µg/g. Finally, it can be concluded that the presence of polyphenols did not significantly affect the biogas potential of pepper waste. Due to its relatively stable biogas production, as f... [more]
The Impact of Cr(III) and Cr(VI) on Lipid Accumulation in Chlorella pyrenoidosa
Tianji Liu, Huawei Guo, Qing Yu, Yajun Wang, Huan Liu, Yanan Zeng, Yitong Wang, Chunyu Liu, Junguo Li
June 5, 2024 (v1)
Subject: Biosystems
Keywords: Chlorella pyrenoidosa, chromium, enzyme activity, lipid, mechanism of lipid synthesis
In this study, Chlorella pyrenoidosa was cultured with different concentrations of Cr(III) and Cr(VI), and the changes in biomass, lipid content, protein content and total sugar content of Chlorella pyrenoidosa under different culture conditions were detected. The effects of Cr(III) and Cr(VI) on the intracellular antioxidant system and related key enzymes of lipid synthesis were analyzed. The results showed that appropriate Cr(III) and Cr(VI) concentrations could make Chlorella pyrenoidosa regulate the contents of SOD, POD, ASA, CAT and GSH in cells, improve the enzyme activity of ACC and promote lipid synthesis. The aim was to investigate the mechanism of lipid synthesis by analyzing the distribution of Cr(III) and Cr(VI) in algal cells. The lipid content of Chlorella pyrenoidosa reached its highest level at 50.43 wt% and 38.00 wt% when both Cr(III) and Cr(VI) concentrations in the culture environment were 0.5 mg/L. These values were 1.37 and 1.03 times higher than the control group,... [more]
Computational Insights into the Interaction between Neprilysin and α-Bisabolol: Proteolytic Activity against Beta-Amyloid Aggregates in Alzheimer’s Disease
Jonathan Elias Rodrigues Martins, José Ednésio da Cruz Freire, Francisco Sérgio Lopes Vasconcelos-Filho, Diego da Silva de Almeida, Vânia Marilande Ceccatto, Bruno Lopes de Sousa
June 5, 2024 (v1)
Subject: Biosystems
Keywords: amyloidogenic pathway, anti-amyloidogenic, levomenol
(1) Background: Alzheimer’s disease (AD) is an irreversible disorder of the central nervous system associated with beta-amyloid protein (Aβ) deposition and accumulation. Current treatments can only act on symptoms and not the etiologic agent. Neprilysin and α-bisabolol have been shown to reduce the aggregation of Aβ, suggesting a potential interaction between both molecules, leading to increased proteolytic activity on Aβ aggregates. (2) Methods: Computational simulations were conducted to explore the interaction between murine neprilysin [NEP(m)] and α-bisabolol and their effects on enzymatic activity. NEP(m) structure was predicted using comparative modeling, and the binding pattern to α-bisabolol and its effects on leu-enkephalin binding were explored through docking calculations and molecular dynamics simulations, respectively. (3) Results: The findings suggest that α-bisabolol stabilizes the Val481-Pro488 segment of NEP2(m), which directly interacts with the peptide substrate, ena... [more]
Special Issue on “Secondary Metabolites: Extraction, Optimization, Identification and Applications in Food, Nutraceutical, and Pharmaceutical Industries”
Ibrahim M. Abu-Reidah
February 19, 2024 (v1)
Subject: Biosystems
There is a growing interest in utilizing natural plant extracts in the food and beverage industries [...]
New Alternatives in the Fight against Tuberculosis: Possible Targets for Resistant Mycobacteria
Eduardo Rodríguez-Bustamante, Saúl Gómez-Manzo, Alvaro De Obeso Fernández del Valle, Roberto Arreguín-Espinosa, Clara Espitia-Pinzón, Eden Rodríguez-Flores
February 19, 2024 (v1)
Subject: Biosystems
Keywords: diarylquinolines, drug resistant TB strains, Mycobacterium tuberculosis, natural products, novel vaccine generation, repurposing drugs, treatment
Tuberculosis (TB) is a bacterial disease that remains a global health threat due to the millions of deaths attributed to it each year. The emergence of drug resistance has exacerbated and further increased the challenges in the fight against this illness. Despite the preventive measures using the application of the Bacillus Calmette-Guérin vaccine, the desired immunization outcome is not as high as expected. Conventional TB treatments exhibit serious limitations, such as adverse effects and prolonged duration, leading to a pressing need for alternative and more effective treatment options. Despite significant efforts, it took nearly four decades for diarylquinoline to become the most recently approved medicine for this disease. In addition, various possibilities, such as the usage of medications used for many other conditions (repurposed drugs), have been explored in order to speed up the process of achieving faster outcomes. Natural compounds derived from various sources (microorganis... [more]
Antimicrobial Resistance of Heterotrophic Bacteria and Enterobacteriaceae Inhabiting an Anthropogenic-Affected River Stretch in Bulgaria
Zvezdimira Tsvetanova, Hristo Najdenski
February 19, 2024 (v1)
Subject: Biosystems
Keywords: antibiotics, antimicrobial resistance, E. coli, Enterobacteriaceae, heterotrophic bacteria, surface water, waste water
The increasing antimicrobial resistance (AMR) of pathogens is a significant threat to human and animal health, but it is also an environmental challenge for water resources. The present study aimed to quantify heterotrophic bacteria resistant to five groups of antibiotics (ABs) in a selected Yantra River stretch (including its tributary, the Belitsa River); to assess AMR prevalence among Enterobacteriaceae; and to assess the impact of urban effluents or rural runoff on AMR prevalence along the river course at eight sampling points. Culture-dependent methods were used in a population-based study of total AMR and for AB susceptibility testing of Enterobacteriaceae isolates. The data reveal significant differences in AMR dissemination and a lower (up to 10%) proportion of different types of antibiotic-resistant bacteria (ARB) in the Yantra River water compared to the Belitsa River (up to 20%). The incidence of resistant Enterobacteriaceae isolates was in the range of 1% to gentamicin to 3... [more]
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