ABSTRACT
The application of lipases in liquid formulation instead of immobilized forms in the enzymatic biodiesel synthesis can make the process cost-efficient, more competitive, and sustainable. However, despite the benefits, the long reaction times required to achieve satisfactory yields is still a drawback of this biotechnological process. In this sense, employing the novel low-cost soluble NS40116 lipase, this paper proposes an innovative two-step hydroesterification reaction (TSHR) system as a technique of improving the reaction rate of an enzymatic biodiesel production. With the employment of two central composite statistical design to optimize the parameters of each of the reactions involved, the influence of the parameters "water concentration added to the reaction," "methanol-to-oil molar ratio," and "lipase load" on the process yield, besides the acid value of the samples, was investigated. After only 8 h of reaction, the highest fatty acid methyl ester yield reached was 97.1% with an acid value of 4.62 mg KOH g-1 utilizing a total of 8 wt% water, methanol-to-oil molar ratio of 6.3:1, and 0.70 wt% of lipase. Furthermore, the statistical models for both reactions indicated to be significant with 95% of reliability. Considering that the papers published using soluble lipases in a one-step batch process normally reach similar yields to those obtained in this research after 16 h to 24 h of reaction, the proposed system demonstrated to be a promising option of process configuration for the enzymatic production of biodiesel.
Subject(s)
Biofuels , Lipase/metabolism , Methanol/metabolism , Plant Oils/metabolism , Biotechnology , Catalysis , Esterification , Fatty Acids/metabolism , Reproducibility of ResultsABSTRACT
The performance of lipase NS 40116, a novel and promising soluble enzyme obtained from modified Thermomyces lanuginosus microorganism, was investigated in the production of biodiesel (fatty acid methyl esters-FAME) by hydroesterification. In order to investigate the potential of the biocatalyst in its soluble form, this work reports the effect of water content and enzyme load, as well as the recovery and reuse of the biocatalyst. A FAME yield of 94.30% after 12 h was achieved at 35 °C by combining 0.50 wt% of lipase, 15 wt% of water, and a methanol:oil molar ratio of 4.5:1. The analysis of the time course reaction suggests that the triacylglycerides (TAGs) are hydrolyzed by the enzyme in a first step, generating free fatty acids (FFAs), followed by the esterification of these FFAs into FAME. In relation to the reusability assays, the lipase kept approximately 90% of its catalytic activity after five cycles of reuse. In this context, the findings of this study demonstrate that lipase NS 40116 can efficiently catalyze hydroesterification reactions under mild conditions, arising as a competitive alternative for biodiesel synthesis.
Subject(s)
Biofuels , Lipase/metabolism , Plant Proteins/metabolism , Soybean Oil/metabolism , Catalysis , Hydrolysis , Soybean Oil/chemistryABSTRACT
This work investigates the use of blends of edible and nonedible raw materials as an alternative feedstock to fatty acid methyl esters (FAME) production through enzymatic catalysis. As biocatalyst, liquid lipase from Thermomyces lanuginosus (Callera™ Trans L), was used. Under reaction conditions of 35 °C, methanol to feedstock molar ratio of 4.5:1 and 1.45% of catalyst load, the best process performance was reached using 9% of water concentration in the medium-yield of 79.9% after 480 min of reaction. In terms of use of tallow mixed with soybean oil, the best yield was obtained when 100% of tallow was used in the process-84.6% after 480 min of reaction-behavior that was associated with the degree of unsaturation of the feedstock, something by that time, not addressed in papers of the area. The results show that tallow can be used as an alternative to FAME production, catalyzed by soluble lipase.
Subject(s)
Ascomycota/enzymology , Fatty Acids/chemistry , Fungal Proteins/chemistry , Lipase/chemistry , Animal FeedABSTRACT
Illusory parasitosis, better known as delusional parasitosis, is a neuropsychiatric syndrome in which patients have the belief of suffering a parasitic disease, that can not be demonstrated after an exhaustive medical study. These patients are characterized by being polyconsultants in different medical specialties and, many of them, have antecedents of psychiatric disorders, some of them undiagnosed. Knowing the existence of the clinical picture, diagnosing early and empathizing with the patient, could give to clinician some clues for a timely and assertive psychiatric referral, and improve patient adherence to the proposed treatment.
Subject(s)
Delusional Parasitosis/diagnosis , Intestinal Diseases, Parasitic/psychology , Skin Diseases, Parasitic/psychology , Aged , Delusional Parasitosis/psychology , Female , Humans , Male , Middle AgedABSTRACT
Illusory parasitosis, better known as delusional parasitosis, is a neuropsychiatric syndrome in which patients have the belief of suffering a parasitic disease, that can not be demonstrated after an exhaustive medical study. These patients are characterized by being polyconsultants in different medical specialties and, many of them, have antecedents of psychiatric disorders, some of them undiagnosed. Knowing the existence of the clinical picture, diagnosing early and empathizing with the patient, could give to clinician some clues for a timely and assertive psychiatric referral, and improve patient adherence to the proposed treatment.
La parasitosis ilusoria, más conocida como delusión parasitaria, es un síndrome neuropsiquiátrico donde los pacientes tienen el convencimiento de padecer una infestación parasitaria, que no puede ser demostrada tras un exhaustivo estudio médico. Estos pacientes se caracterizan por ser policonsultantes en distintas especialidades médicas y, muchos de ellos, poseen antecedentes de trastornos psiquiátricos, algunos de ellos no diagnosticados. Conocer la existencia del cuadro, diagnosticar precozmente y empatizar con el paciente, pueden dar al médico clínico algunas claves para una derivación psiquiátrica oportuna y asertiva, y mejorar la adherencia del paciente al tratamiento propuesto. Se presentan cuatro casos clínicos que consultaron por esta extraña condición.
