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Nonlinear regression for the characterization of peristaltic pumps, an alternative in the control of biological fluids

Ramírez Carvajal, Luis Eduardo | 2024-02-24

This paper presents a modeling approach to characterize two peristaltic pumps using nonlinear regression. Accuracy tests were performed by varying the height level of the pump with respect to the vessel, and it was found to have no effect on the flow rate. Filling data was recorded for 300 ml considering the voltage applied to the pumps and the filling time. A least squares curve fitting was performed with the recorded data. The exponential model was determined to be the most accurate for the two pumps, and using a simple rule of three, the equation for each desired volume was found. Finally, filling tests were performed to compare the model data with the real data. The coefficient of determination of the model for the first pump was 0.9875 and for the second pump was 0.9956. It can be concluded that the models are accurate, which is also confirmed in the comparative filling tests, where an assertiveness of more than 99% was demonstrated in all the tests performed. It is proposed to extend the studies on the use of this mathematical method as an alternative in the non-invasive control of fluids whose instruments must be handled in a sterile manner.

Influence of Critical Parameters on the Extraction of Concentrated C-PE from Thermotolerant Cyanobacteria

Vergel-Suarez, Ariadna H. | 2024-06-24

This work aimed to identify the influence of pH, molarity, w/v fraction, extraction time, agitation, and either a sodium (Na2HPO4 ·7H2O-NaH2PO4 ·H2O) or potassium buffer (K2HPO4 -KH2PO4 ) used in the extraction of C-phycoerythrin (C-PE) from a thermotolerant strain of Potamosiphon sp. An experimental design (Minimum Run Resolution V Factorial Design) and a Central Composite Design (CCD) were used. According to the statistical results of the first design, the K-PO4 buffer, pH, molarity, and w/v fraction are vital factors that enhance the extractability of C-PE. The construction of a CCD design of the experiments suggests that the potassium phosphate buffer at pH 5.8, longer extraction times (50 min), and minimal extraction speed (1000 rpm) are ideal for maximizing C-PE concentration, while purity is unaffected by the design conditions. This optimization improves extraction yields and maintains the desired bright purple color of the phycobiliprotein

Production of industrial-interest colorants in microalgae and cyanobacteria: leveraging nutrient dynamics and photoperiod optimization

Contreras Ropero, Jefferson Eduardo | 2024-07-15

The exploration of the biodiversity of cyanobacteria and microalgae holds great promise for obtaining pigments of industrial interest. This study focused on the bioprospecting of these organisms to obtain pigments of industrial interest together with enriched biomass. We investigated the impact of photoperiod and concentration of C/N/P nutrient sources in heterotrophic cultures, controlling specific variables such as light intensity, volume, pH, temperature, air flow and time to produce phycobiliproteins in Arthrospira platensis UTEX1926 and total carotenoids in Scenedesmus sp. using a nonfactorial Plackett‒Burman design in STATISTICA 7.0 software. The biomass concentration was determined by dry weight, while the concentrations of phycocyanin and carotenoids were determined spectrophotometrically at specific wavelengths. Heterotrophic cultures demonstrated superior productivity, with phycocyanin and carotenoids achieving percentages of 7% and 0.4% (w/w), respectively, and an R2 value of 0.99. Among the influential parameters, potassium diphosphate and sodium bicarbonate played pivotal roles in the final deposition of carotenoids and phycocyanin, respectively, yielding concentrations of 96.5 mg/L phycocyanin and 6.5 mg/L carotenoids

Use of mining effluents for the production of algal-based colorants

Perez-Roa, Michael Edgardo | 2024-08-11

In this research, a mining effluent was used to produce microalgal and cyanobacterial bio-mass to obtain red (carotenoids) and blue pigments (phycocyanin). Two strains were isolated from a hydrothermal source in Norte de Santander and grown in mining wastewater mixed with 50% BG-11 medium for the Osci_UFPS01 cyanobacterium and 50% with Bold Basal me-dium for the Chlo_UFPS01 microalgae. A carbon, nitrogen, and phosphorus experiment de-sign was developed, and subsequent response surface analysis (RSM) was used to determine the optimal operating conditions for the formation of the products of interest. A notable de-crease in pigment production was observed compared to that in the controls without mining wastewater. Overall, 45% of phycocyanin (C PC) per unit dry weight (DW) and 1,129% (w/w) of carotenoids were obtained in the cultures with a mining wastewater mixture in the final optimization processes

Optimization of phycobiliprotein biosynthesis in thermotolerant cyanobacteria through light parameter adjustment

Contreras Ropero, Jefferson Eduardo | 2024-08-06

This study addressed the optimization of biomass and C-phycocyanin (C-PC) concentration and its purity in the thermotolerant cyanobacterium Potamosiphon sp by adjusting key light quality parameters. Custom design and Central Composite Design experimental designs were employed, using LEDs light intensity, wavelength, and photoperiod. The results demonstrated that these lighting parameters significantly influence biomass and Cphycocyanin production, achieving up to a 100 % increase in phycocyanin accumulation and biomass production and a 50 % improvement in purity index compared to conventional white light under optimal conditions of Red: Blue light (3:1), Intensity (283 μmol m− 2 s− 1 ), and photoperiod (17.8 H light). The findings support the use of specific LEDs wavelengths that optimize the performance of production processes and the quality of products derived from cyanobacteria, such as high-value phycobiliproteins.

Antibacterial and Photocatalytic Applications of Silver Nanoparticles Synthesized from Lacticaseibacillus rhamnosus

LAVECCHIA, Roberto | 2024-11-03

The biosynthesis of silver nanoparticles (AgNPs) presents an innovative and sustainable approach in nanotechnology with promising applications in fields such as medicine, food safety, and pharmacology. In this study, AgNPs were successfully synthesized using the probiotic strain Lacticaseibacillus rhamnosus (BCRC16000), addressing challenges related to stability, biocompatibility, and scalability that are common in conventional nanoparticle production methods. The formation of AgNPs was indicated by a color change from yellow to brown, and UV–visible spectrophotometry confirmed their presence with a characteristic absorption peak at 443 nm. Furthermore, Fourier transform infrared (FTIR) spectroscopy revealed the involvement of biomolecules in reducing silver ions, which suggests their role in stabilizing the nanoparticles. In addition, field emission scanning electron microscopy (FE-SEM) showed significant morphological and structural changes. At the same time, dynamic light scattering (DLS) and zeta potential analyses provided valuable insights such as average size (199.7 nm), distribution, and stability, reporting a polydispersity index of 0.239 and a surface charge of −36.3 mV. Notably, the AgNPs demonstrated strong antibacterial activity and photocatalytic efficiency, underscoring their potential for environmental and biomedical applications. Therefore, this study highlights the effectiveness of Lacticaseibacillus rhamnosus in the biosynthesis of AgNPs, offering valuable antibacterial and photocatalytic properties with significant industrial and scientific implications.

Natural Antimicrobial Agents from Algae: Current Advances and Future Directions

ZUORRO, Antonio | 2024-11-04

Infectious diseases have significantly shaped human history, leading to significant advancements in medical science. The discovery and development of antibiotics represented a critical breakthrough, but the rise of antibiotic-resistant pathogens now presents a serious global health threat. Due to the limitations of current synthetic antimicrobials, such as toxicity and environmental concerns, it is essential to explore alternative solutions. Algae, particularly microalgae and cyanobacteria, have emerged as promising sources of bioactive antimicrobial compounds. This review provides a comprehensive analysis of the antimicrobial properties of algal-derived compounds, including polysaccharides, fatty acids, and phenols, which have shown effectiveness against multi-drug-resistant bacteria. A co-occurrence bibliometric analysis using VOSviewer highlighted five key research clusters: antibiotic resistance, algal extracts, biosynthesis, water treatment, and novel pharmacological compounds. Furthermore, the primary mechanisms of action of these bioactive compounds, such as the inhibition of protein synthesis and cell membrane disruption, were identified, demonstrating their potential against both common and multi-resistant pathogens. Future research should prioritize optimizing algal biomass production, utilizing genetic and metabolic engineering, and creating innovative delivery systems to enhance the efficient production of bioactive compounds.

Impact of colchicine on leaf morphology and stomatics of Kalanchoe tubiflora (Harv.) Raym.- Hamet (Crassulaceae)

SALAZAR MERCADO, SEIR ANTONIO | 2021-09-24

The demand of medicinal plants for consumption is greatly increasing worldwide. The conventional breeding programs are generally dependent on the environment prone to biotic and abiotic stresses. These added to the low content of secondary metabolites at harvest, bring the need for artificial development of polyploid individuals as an alternative to increase productivity. Consequently, the present study evaluated the effect of different colchicine concentrations and exposure time, on Kalanchoe tubiflora leaf morphology and stomata. Initially, K. tubiflora seedlings were harvested and submitted to colchicine concentrations of 0, 0.025, 0.05 and 0.1 % and at two exposure times (24 and 48 hours). Subsequently, morphological measurements such as plant height, leaf width, leaves number, leaf length, leaf thickness and leaf volume every 15 days were made for 16 weeks after planting. Then, the stomata were characterized, taking into account the width, length, stomatal index and the number of chloroplasts per stoma. A significant increase in leaf morphology was found in colchicine treatments of 0.025 % at 48 h and 0.1 % at 24 h. A significant increase in stomatal morphology with the treatment of 0.025 % at 24 h was also recorded. This shows that the correct application of colchicine in term of quantity and time could produce greater growth in a short period and increase the biomass of K. tubiflora medicinal plant

Viability of seeds of two varieties of Coffea arabica L. using different pretreatments in the tetrazolium test

BUENDIA CONTRERAS, JOSE DUVAN | 2023-10-13

This research attempted to determine the efficacy of the tetrazolium test in the evaluation of the seed viability of two varieties of Coffea arabica L. (‘Castillo’ and ‘Cenicafé’). The fruits were obtained from crops located in the municipalities of Salazar de las Palmas and Arboledas (Norte de Santander - Colombia). The test was carried out with embryos manually extracted from the seeds using tweezers. Three pretreatments were established: distilled water, sodium hypochlorite (2.5 %), sucrose (10 %), and a control (no pretreatment). Embryos were placed in a cysteine solution (0.5 %) to prevent oxidation, then immersed in tetrazolium solutions with concentrations of 0.035 %, 0.075 %, and 0.1 % for a period of 6, 9, and 12 hours in darkness. The results of the viability test were validated with seed germination, using the wet paper towel method in darkness. The best viability percentages were found with the application of sodium hypochlorite (NaClO 2.5 %), with a high correlation with the germination percentage. The use of pretreatments improved the efficiency of the viability test and allowed the use of low concentrations of the reagent (0.035 %), giving the farmer a quick and less expensive alternative to determine germination capacity.

A Simulation Analysis of an Influenza Vaccine Production Plant in Areas of High Humanitarian Flow. A Preliminary Study for the Region of Norte de Santander (Colombia)

Contreras Ropero, Jefferson Eduardo | 2021-12-24

The production of vaccines of biological origin presents a tremendous challenge for researchers. In this context, animal cell cultures are an excellent alternative for the isolation and production of biologicals against several viruses, since they have an affinity with viruses and a great capacity for their replicability. Different variables have been studied to know the system’s ideal parameters, allowing it to obtain profitable and competitive products. Consequently, this work focuses its efforts on evaluating an alternative for producing an anti-influenza biological from MDCK cells using SuperPro Designer v8.0 software. The process uses the DMEN culture medium supplemented with nutrients as raw material for cell development; the MDCK cells were obtained from a potential scale-up with a final working volume of 500 L, four days of residence time, inoculum volume of 10%, and continuous working mode with up to a total of 7400 h/Yr of work. The scheme has the necessary equipment for the vaccine’s production, infection, and manufacture with yields of up to 416,698 units/h. In addition, it was estimated to be economically viable to produce recombinant vaccines with competitive prices of up to 0.31 USD/unit.

Integrated cloud computing and cost effective modelling to delineate the ecological corridors for Spectacled bears (Tremarctos ornatus) in the rural territories of the Peruvian Amazon

Cotrina Sanchez, Alexander | 2022-04-19

Spectacled bears (SB) (Tremarctos ornatus) are the only bear species native to South America. This particular bear is the single species of its genus, and it is listed as vulnerable according to the IUCN red list. A critical SB conservation habitat is in the rural territories of the Peruvian Amazon, where anthropogenic land-use changes and landscape fragmentation threaten SB habitats. The following questions arise in this context: How much has land-use changed? How to design the establishment of ecological corridors (ECs) to support the conservation of SB?. We investigated the temporal land use and land cover changes for last 30 years (1990–2020) for a better projection of the ECs and to quantify the temporal landscape metrics. Furthermore, we integrated cloud computing, machine learning models with cost-effective techniques to delineate the ECs for SB within the rural territories. Ensemble Random Forest model associated with Google Earth Engine (GEE) was used to develop four land use and land cover (LULC) maps (for the years 1990, 2000, 2010 and 2020). The least cost path (LCP) model based on Dijkstra’s shortest path algorithm was assembled based on six variables (altitude; slope; distance to roads; distance to population centers; land use map; inventory map of SB). Then, we calculated the ECs based on the multidirectional origin-destination points, we found that forest patches increased by 57%

WaterrelationsandgasexchangeinRuilopezia atropurpurea(Asteraceae),agiantrosettegrowingundercontrastingmicroclimatesinthehightropicalAndes

Rada, Fermin | 2022-10-10

Tropical high andean ecosystems, known as paramos, are unique because they are highly diverse, have a high number of endemic species, and play an essential role in different ecosystem services, but are especially susceptible to climate change. Most of the giant rosettes, a dominant growth-form in the paramos, depend on unique features like stems protected by marcescent leaves, voluminous stem pith, and leaf pubescence. However, Ruilopezia atropurpurea lacks these characteristics and must respond differently to endure the paramo extreme conditions. Additionally, unlike other rosettes, this species is found under contrasting exposed and understory microenvironments so that intraspecific plasticity is also expected. We evaluated the responses of R. atropurpurea in terms of leaf water relations, gas exchange, and morphological characteristics in temporal (seasonal and daily variations) and spatial (microsite differences) scales in a Venezuelan paramo. R. atropurpurea displayed lower leaf water potentials (minimum leaf water potentials of -1.5 MPa and -1.8 MPa at the turgor loss point), higher leaf conductance (620 mmol m-2s-1), transpiration (5 molm-2s-1), and CO2 assimilation (13 mmol m-2s-1) rates compared to other paramo giant rosettes. A reduction in leaf area and specific leaf area occurred from understory to exposed sites. R. atropurpurea diverges from the typical responses of most paramo giant rosettes to the extreme environmental conditions. This species’ morphological and physiological plasticity permits it inhabit under variable microclimatic conditions, but despite its confirmed plasticity, it is not able to reach higher elevations as other giant rosettes successfully have.

The Effect of LEDs on Biomass and Phycobiliproteins Production in Thermotolerant Oscillatoria sp.

Contreras Ropero, Jefferson Eduardo | 2022-11-17

This study evaluates the role of different LED lights (white, blue/red), intensity (µmol m−2 s −1 ), and photoperiod in the production of biomass and phycocyanin-C, allophycocyanin and phycoerythrin (C-PC, APC, and PE respectively) from a novel thermotolerant strain of Oscillatoria sp. Results show that a mixture of white with blue/red LEDs can effectively double the biomass concentration up to 1.3 g/L, while the concentration of the selected phycobiliproteins increased proportionally to biomass. Results also indicate that high light intensities (>120 µmol m−2 s −1 ) can diminish the final concentration of C-PC, APC, and PE, significantly reducing the overall biomass produced. Finally, the photoperiod analysis showed that longer light exposure times (18:6 h) improved both biomass and phycobiliproteins concentration. These results demonstrate that the application of LEDs to produce a novel strain of Oscillatoria sp can double the biomass concentration, and the photoperiod regulation can eventually enhance the final concentration of specific phycobiliproteins such as APC and PE.

Evaluation of microorganisms response to soil physical conditions under different agriculture use systems

Visconti Moreno, Efrain Francisco | 2024-01-01

Soils with appropriate water and air conditions improve microbiological activity, but agriculture frequently deteriorates soil’s physical requirements and impairs microbes’ survival. The main aim of this study was to evaluate the relationship between physical soil conditions and microbiological activity under different agricultural use and management systems in the warm tropical climate of Colombia. To evaluate physical soil conditions, bulk density (Bd), total porosity (Pt), macroporosity (MPt), water content, temperature, and mechanical penetration resistance (MPR) were measured on surface soil (0 to 10 cm) at three different use and management systems: irrigated rice (IR), pasture (P) and native forest with cacao (FC). The measured biological properties were the carbon of microbial biomass (C-MB) and the presence of bacteria and fungi. Soil organic carbon (SOC) was determined to calculate the microbiological quotient (MQ). The C-MB was significantly higher in FC (132.25) and P (148.11) but lower in IR (41.61). No significant differences were observed between the soil use system in the count of bacteria and fungi. The MQ (0.44) was higher in IR (0.22), revealing a significant effect of the soil use system on microbiological activity. Less anthropic intervention and permanent plant covers, such as FC and P, enhance microorganism’s survival, evidenced by higher C-MB content, correlated with soil Bd and MPt. The abundance of bacteria and fungi in the soil is affected by the physical conditions, primarily by Pt and MPt. However, fungi survive better with less water content, existing a differentiated effect of the physical conditions of the soil.

S-curve and landscape maps for the analysis of trends on industrial textile wastewater treatment

Urbina-Suarez, Nestor Andres | 2024-01-18

The textile industry is one of the most important and economically significant industries in the world. China is the largest textile producer, for countries such as India, Pakistan, Bangladesh and Malaysia this sector is of crucial importance and it is also a growing sector in Latin America. This industry is responsible for 10 % of annual global carbon emissions and 20 % of global wastewater. This figure is worrying as this wastewater is highly recalcitrant, which has led to research into different treatment methods that are efficient and can provide a sustainable solution to this problem. The aim of this literature review was to identify the existing methods for the treatment of dry scrubber wastewater (TWWT) and the effects of this wastewater and its composition, focusing on biological, chemical and physicochemical processes from the point of view of advantages and disadvantages. It was analyzed which are the most important scientific areas of TWWT and which countries are the most important in this field, as well as the primary pollutants and TWWT processes. Finally, this analysis provides a context for current trends in TWWT research. In general, coagulation methods have been found to be fast but present difficulties due to the use of toxic coagulants; advanced oxidation processes (AOPs) are positioned as very effective methods that can disinfect and decontaminate these effluents. Currently, biological systems coupled with AOPs are a growing trend. Microalgae and cyanobacteria processes coupled with AOPs have attracted great interest due to the possibility of obtaining high added value products through the biorefining of biomass.

Pores distribution influences the soil microorganism's response to changes in temperature and moisture

Visconti Moreno, Efrain Francisco | 2023-01-01

Microorganisms are an essential fraction of soil organic matter, which presence and activity depend directly on soil physical conditions. This study aimed to address the effect of soil temperature and moisture under contrasting macroporosity conditions on soil biological properties. Soil physical-chemical characterization implicated the collection of composite samples and undisturbed surface soil samples (0 to 10 cm). Also, samples of undisturbed surface soil were extracted in 40 polyvinyl chloride cylinders of 18 cm diameter and 20 cm height for the arrangement of soil mesocosm as the experimental units of a completely randomized experiment with a 2x2x3 factorial arrangement. The experiment duration was 21 days, and the soil biological properties measured were microbial biomass (MB) and soil respiration (SR). Macroporosity showed a significant effect on MB, which indicates that aeration pore influences the number of microorganisms in the soil; for the SR, the macroporosity had a not significant effect. The temperature at the ranges established in the experiment did not significantly affect MB, whereas a highly significant effect of temperature over SR was observed. A highly significant effect of soil moisture was observed on MB and SR. Macroporosity, moisture, and temperature are determining factors in the presence of soil microorganisms, both directly and through the interaction between them. Herein the microorganisms have a wide range of thermal adaptation, and the effect of soil temperature can boost soil microorganisms. In turn, it was observed that the microorganisms present are significantly sensitive to the moisture deficit in soil.

A Technoeconomic Resilience and Exergy Analysis Approach for the Evaluation of a Vaccine Production Plant in North-East Colombia

González-Delgado, Angel Darío | 2022-12-24

Influenza is an acute infection that can cause diabetes and heart and lung disease disorders. This illness affects more than 9 million people around the world. The best way to control the transmission of the virus is vaccination. Studies, performed in Santander, Colombia, have found the existence of this disease. Despite the above, there are no companies dedicated to producing influenza vaccines in Colombia. For the first time, exergetic analysis and technical-economic resilience are being performed as combined decision-making tools for the evaluation of an influenza vaccine production plant. The results of exergetic analysis showed that the global exergy efficiency of the process was estimated at 93%. The exergy of waste that resulted was 61.70 MJ/h. The most critical stage of the process is milling, representing 83% of the total destroyed exergy. On the other hand, the results of technoeconomic resilience showed that the break-even point capacity of the process is 2503.15 t/y, representing only 24% of the installed capacity of the plant. The analysis of the effect of raw materials cost on profits showed that the process only resists a rise of 4% in the cost of raw materials, and higher values show economic losses. A value of 215,500 USD/t establishes a critical point for the normalized variable operating costs because higher values do not provide a return on investment.

Paracetamol ecotoxicological bioassay using the bioindicators Lens culinaris Med. and Pisum sativum L

SALAZAR MERCADO, SEIR ANTONIO | 2023-03-18

Paracetamol is one of the most widely used drugs worldwide, yet its environmental presence and hazardous impact on nontarget organisms could rapidly increase. In this study, the possible cytotoxic efects of paracetamol were evaluated using two bioindicator plants Lens culinaris and Pisum sativum. Concentrations of 500, 400, 300, 200, 100, 50, 25, 5, 1 mg L−1, and a control (distilled water) were used for a total of 10 treatments, which were subsequently applied on seeds of Lens culinaris Med. and Pisum sativum L.; after 72 h of exposure, root growth, mitotic index, percentage of chromosomal abnormalities, and the presence of micronucleus were evaluated. The cytotoxic efect of paracetamol on L. culinaris and P. sativum was demonstrated, reporting the inhibition of root growth, the presence of abnormalities, and a signifcant micronucleus index at all concentrations used, which shows that this drug has a high degree of toxicity.

Genetic control of yield components in green beans (Phaseolus vulgaris L.)

Contreras Rojas, Mayra | 2023-09-04

. For most of the traits, except yield per plant, the additive-dominant model was adequate. Non-additive effects with overdominance controlled the number of pods per plant, pod length, and mean pod weight. Most of the characters presented an unequal proportion of positive and negative genes in the loci (H1 < H2 ). The asymmetric distribution of genes in the parents (H2 /4H1 ) was below the maximum value (0.25), except for the character “number of pods per plant”. The KD/KR ratio confirmed for most of the traits that there was an excess of recessive alleles over dominant alleles. Dominance effects (h2 ) for most characters suggested that the substantial contribution of dominance was not due to heterogeneity of loci in these characters. The narrow-sense heritability was moderate to low. The correlation coefficient r (Yr; Wr + Vr) indicated that dominant genes were responsible for the increased number of pods per plant and recessive genes for increased pod length and mean pod weight. Conclusions. Conventional breeding methods like pedigree selection could be employed to improve the characters “pod length” and “mean pod weight”, and for the number of pods per plant, management of segregating populations should employ the single-seeded descent method.

Bicarbonate-Hydrogen Peroxide System for Treating Dyeing Wastewater: Degradation of Organic Pollutants and Color Removal

Urbina-Suarez, Nestor Andres | 2023-04-11

: The textile industry is a global economic driving force; however, it is also one of the most polluting industries, with highly toxic effluents which are complex to treat due to the recalcitrant nature of some compounds present in these effluents. This research focuses on the removal of Chemical Oxygen Demand (COD), color, Total Organic Carbon (TOC), and Ammoniacal Nitrogen (N-NH3 ) on tannery wastewater treatment through an advanced oxidation process (AOPs) using sodium bicarbonate (NaHCO3 ), hydrogen peroxide (H2O2 ) and temperature using a central composite non-factorial design with a surface response using Statistica 7.0 software. All experiments used a 500 mL reactor with 300 mL of tannery wastewater from a company in Cúcuta, Colombia. The physicochemical characterization was done to determine the significant absorbance peaks about the color in the wavelengths between 297 and 669 nm. Statistical analysis found that the concentration of NaHCO3 affects the removal of color and N-NH3 ; however, it did not affect COD and TOC. The optimal process conditions for removing the different compounds under study were: NaHCO3 1 M, H2O2 2 M, and 60 ◦C, with efficiencies of 92.35%, 31.93%, 68.85%, and 35.5% N-NH3 , COD, color, and TOC respectively. It can be concluded that AOPs using H2O2 and NaHCO3 are recommended to remove color and N-NH3.