Walter Murillo Arango

Prof. Walter Murillo Arango

Universidad del Tolima, Ibagué, Colombia
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orcid

Research Focus & Metrics

Academic Career Length

58Years (1969-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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9 March 2021 in Molecules
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Journal Article
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LHLicelander Hennessey
Licelander Hennessey
WAWalter Murillo Arango
Walter Murillo Arango
Juliana Vasco-CorreaJuliana Vasco-Correa
Juliana Vasco-Correa
IAIsabel Cristina Paz Astudillo
Isabel Cristina Paz Astudillo
Cocoa pod husks are a waste generated during the processing of cocoa beans. We aimed to explore the enzymatic extraction of pectin using cellulases. The extraction process was optimized using a central composite design (CCD) and analyzed by response surface methodology (RSM). The parameters optimized were feedstock concentration (%), enzyme dosage (µL/g), and time (h). Three dependent variables were studied: pectin yield (g/100 g dry husk) (R2 = 97.02), galacturonic acid content (g/100 g pectin) (R2 = 96.90), and galacturonic acid yield (g/100 g feedstock) (R2 = 95.35). The optimal parameters were 6.0% feedstock concentration, 40 µL g−1 of enzyme, and 18.54 h, conditions that produced experimentally a pectin yield of 10.20 g/100 g feedstock, 52.06 g galacturonic acid/100 g pectin, and a yield 5.31 g galacturonic acid/100 g feedstock. Using the chemical extraction method, a yield of 8.08 g pectin/100 g feedstock and a galacturonic acid content of 60.97 g/100 g pectin were obtained. Using assisted sonication, a pectin yield of 8.28 g/100 g feedstock and a galacturonic acid content of 42.77 g/100 g pectin were obtained. Enzymatically optimized pectin has rheological and physicochemical features typical of this biomaterial, which provides an interesting alternative for the valorization of cocoa husks.

16 December 2020 in Molecules
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NGNathalie Guarnizo
Nathalie Guarnizo
DODiego Oliveros
Diego Oliveros
WAWalter Murillo Arango
Walter Murillo Arango
MBMaría Bianney Bermúdez-Cardona
María Bianney Bermúdez-Cardona
Plants have innate immune systems or defense mechanisms that respond to the attack of pathogenic microorganisms. Unlike mammals, they lack mobile defense cells, so defense processes depend on autonomous cellular events with a broad repertoire of recognition to detect pathogens, which compensates for the lack of an adaptive immune system. These defense mechanisms remain inactive or latent until they are activated after exposure or contact with inducing agents, or after the application of the inductor; they remain inactive only until they are affected by a pathogen or challenged by an elicitor from the same. Resistance induction represents a focus of interest, as it promotes the activation of plant defense mechanisms, reducing the use of chemical synthesis pesticides, an alternative that has even led to the generation of new commercial products with high efficiency, stability and lower environmental impact, which increase productivity by reducing not only losses but also increasing plant growth. Considering the above, the objective of this review is to address the issue of resistance induction with a focus on the potential of the use of oligosaccharides in agriculture, how they are recognized by plants, how they can be used for commercial products and perspectives.

1 May 2019 in Revista Facultad Nacional de Agronomía Medellín
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LHLicelander Hennessey
Licelander Hennessey
WAWalter Murillo Arango
Walter Murillo Arango
GGGiovanni Tovar Guayabo
Giovanni Tovar Guayabo
The present research evaluated the antioxidant, antimicrobial and in vitro coloring capacity of extracts with different polarity obtained from avocado seeds (Persea americana Mill cv. Lorena). Besides, avocado oil was extracted from the residual mesocarps of P. americana Mill Hass cultivar by Soxhlet methodology, and the physicochemical properties of the extracted oil, as well as its fatty acid composition, were evaluated. Both the colorant and the avocado oil were used as supplies for a liquid soap type formulation. The antioxidant activity of the colorant extracts was determined by DPPH whereby water extracts showed the highest activity among the treatments. None of the extracts showed antimicrobial activity against Staphylococcus aureus ATCC 29213 and Escherichia coli ATCC 25922. The iodine value (177.52 cg I2 g-1) indicated that the avocado oil obtained has a high degree of unsaturation, and the Saponification index had a value of 190.74 mg KOH g-1. The colorant extracted with NaOH (L*=0.15, a*=0.05, and b*=-0.44) from the seeds was completely stable in a liquid soap matrix at pH 6.2 during one month of storage. This analysis suggests that it has high opportunities in the soap and cosmetic industry.

14 July 2014 in Toxins
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SGSebastian Estrada Gomez
Sebastian Estrada Gomez
NCNelson Ivan Cupitra
Nelson Ivan Cupitra
WAWalter Murillo Arango
Walter Murillo Arango
LMLeidy Johana Vargas Muñoz
Leidy Johana Vargas Muñoz
We report the first description studies, partial characterization, and intraspecific difference of Centruroides edwardsii, Gervais 1843, venom. C. edwardsii from two Colombian regions (Antioquia and Tolima) were evaluated. Both venoms showed hemolytic activity, possibly dependent of enzymatic active phospholipases, and neither coagulant nor proteolytic activities were observed. Venom electrophoretic profile showed significant differences between C. edwardsii venom from both regions. A high concentration of proteins with molecular masses between 31 kDa and 97.4 kDa, and an important concentration close or below 14.4 kDa were detected. RP-HPLC retention times between 38.2 min and 42.1 min, showed bands close to 14.4 kDa, which may correspond to phospholipases. RP-HPLC venom profile showed a well conserved region in both venoms between 7 and 17 min, after this, significant differences were detected. From Tolima region venom, 50 well-defined peaks were detected, while in the Antioquia region venom, 55 well-defined peaks were detected. Larvicidal activity was only detected in the C. edwardsii venom from Antioquia. No antimicrobial activity was observed using complete venom or RP-HPLC collected fractions of both venoms. Lethally activity (carried out on female albino swiss mice) was detected at doses over 19.2 mg/kg of crude venom. Toxic effects included distress, excitability, eye irritation and secretions, hyperventilation, ataxia, paralysis, and salivation.

28 April 2023 in Microorganisms
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LDLINA ROCIO DAVILA
LINA ROCIO DAVILA
CJClaudia Cristina Pérez Jaramillo
Claudia Cristina Pérez Jaramillo
JAJonh Jairo Méndez Arteaga
Jonh Jairo Méndez Arteaga
WAWalter Murillo Arango
Walter Murillo Arango
Macrofungi are among the most promising sources of biologically active natural products with nutritional qualities and therapeutic values. In this work, the nutritional value of nine species of wild macrofungi from Ibague-Tolima (Colombia) was evaluated. In addition the antioxidant, antimicrobial and cytotoxic activities of an ethanol:water (70:30) extract of wild basidiomata were evaluated. The wild mushrooms’ nutritional potential showed that the genus Pleurotus and Lentinus have the best protein percentages, with 18.4% and 18.5%. The nine extracts evaluated managed to stabilize the two radicals evaluated; however, lower IC50 was found for Phellinus gilvus and Ganoderma australe extracts. The results showed that Trametes coccinea, Pleurotus floridanus and Ganoderma australe extracts were the most effective as antimicrobials, with high inhibition percentages against Staphylococcus aureus, Escherichia coli, Pseudomonas aeruginosa and Klebsiella pneumoniae. Antifungal activity results against Rhizopus oryzae, Penicillium sp. and Aspergillus niger showed that the nine extracts were effective at the concentrations tested. Considering cell viability against isolated leukocytes, seven of the nine extracts showed percentages higher than 50% of cell viability. This research describes the nutritional value of nine wild macrofungi in Colombia and their potential for antimicrobial, cytotoxic and antioxidant activity.

19 August 2020 in Biomass Conversion and Biorefinery
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LDLINA ROCIO DAVILA
LINA ROCIO DAVILA
CFCristian Javier Zambrano Forero
Cristian Javier Zambrano Forero
OTOscar Torres-Arango
Oscar Torres-Arango
JBJhon Betancur
Jhon Betancur
WAWalter Murillo Arango
Walter Murillo Arango