Kinetic study of a commercial lipase for hydrolysis of semi-refined oil of anchovy (Engraulis ringens) [Estudio cinético de una lipasa comercial para la hidrólisis de aceite semirrefinado de anchoa (Engraulis ringens)]

Lipases due to their ecological nature and catalytic versatility, are ideal for their application in the fish oil hydrolysis industry due to their selective property, which allows the preservation of polyunsaturated fatty acids (PUFAs) in the lipid structure. The objective of this research was to determine the activity and kinetic parameters of a commercial AY AMANO "30SD" lipase, as well as the temperature and time values ​​to achieve an optimal degree of hydrolysis in semi-refined anchovy oil. The experiments were carried out in a jacketed minireactor with a working volume of 400 mL (oil-water-enzyme) with temperature control and pH 7.00, enzyme concentration 350 U/mL and stirring 160 rpm. A 3x3 factorial design and the response surface methodology were used. The results obtained from the study of the enzyme were: activity = 37 384.55 ± 395.07 U/g and kinetic parameters: Km = 7.98 g/L and Vmax. = 0.038887 g/Lxmin. Correspondingly, the following optimal parameters were obtained: Degree of hydrolysis 4.01%, temperature 46.86 °C and hydrolysis time 90 minutes, with a confidence level of 95% (p <0.05). Conclusions: The study allowed us to kinetically characterize the commercial lipase and determine the optimum degree of hydrolysis of the semi-refined anchovy oil.

Improving Dyeing Properties of Cotton Fabrics to Natural Dyes with Cellulose Nanocrystals (CNCs) [Mejora de las propiedades de teñido de telas de algodón a tintes naturales con nanocristales de celulosa (CNC)]

Natural dyes can make less environmental problems associated with manufactured colouring agents and textile dyeing. But, the natural dyes fixing process was used chemicals called mordant. The most of times mordants were used metallic salts and metal salts mordants were not environmentally friendly. Therefore, remove the disadvantage associated with natural colorants and the use of nanoparticles. In this research, cotton fabric was treated with the nanoparticle of cellulose nanocrystals (CNCs) as mordant. The cellulose nanocrystals extraction process was done by using Whatman filter paper. The cellulose nanocrystals obtained will be further analyzed and characterized by using selected tools such as Particle size analysis and Fourier-transform infrared (FTIR) spectroscopy. The cotton fabrics mordanting processes were done by two types of pre-mordanting and post-mordanting methods. The three natural ingredients of Mangifera indica (Mango) leaves, Tectona grandis (Teak) leaves and Lannea coromandelica (Indian ash tree) leaves were used to extract the natural dyes using with aqueous extraction method. The extracts from dyeing processes were carried out after and before mordanting processes. The dyed sample from colour fastness to light, washing, and crocking were assessed according to standard methods. The cellulose nanocrystals gave very good colour fastness to light, wash, and rubbing when dyed with all three dye extractions. In the present study, innovative mordant of cellulose nanocrystals and natural dyeing with three natural dye extractions have been shown to give good dyeing results with cotton fabric.

Adsorption of lead and iron present in the waters of the Santa River using titanium dioxide nanoparticles (TiO2) [Adsorción de plomo y hierro presentes en aguas del río Santa utilizando nanopartículas de dióxido de titanio (TiO2)]

The objective of the investigation was to determine adsorption of lead and iron in waters coming from the Santa River, Recuay jurisdiction, Ancash. Then the synthesis of titanium dioxide nanoparticles (TiO2) was carried out by means of ultrasound, and finally the adsorption of the metal ions present in these waters by means of the titanium dioxide nanoparticles. The results indicate that the iron was adsorbed by 92.69% (from 31.86 mg/L to 2.33 mg/L) and the lead was adsorbed by 79.58% (from 2.361 mg/L to 0.482 mg/L) using 600mg of titanium dioxide nanoparticles (TiO2) and a treatment time of 60 minutes of treatment.

Reduction of organic and biological pollutants from affluents of the Ancón wastewater treatment plant using microanobubbles of air and graphene [Reducción de contaminantes orgánicos y biológicos de afluentes de la planta de tratamiento de aguas residuales de Ancón utilizando micronanoburbujas de aire y grafeno]

The objective of this research was to reduce the organic and biological load of tributaries of the Ancón Wastewater Treatment Plant using microanobubbles of air and graphene. A preliminary sample of the affluent (3L) was taken, which had an initial concentration of Biochemical Oxygen Demand (BOD5) of 410 mg/L, Chemical Oxygen Demand (COD) of 483 mg/L, Thermotolerant Coliforms of 44,000 NMP/100mL and turbidity of 63.33 NTU. The experimental part was carried out with 03 samples of 20 liters with 03 repetitions with a treatment time of 20, 40 and 60 minutes applying air nanobubbles and 6, 12 and 18 grams of graphene respectively. The results of the treated samples were: 87 mg/L representing 78.8% reduction in Biochemical Oxygen Demand (BOD5), 114 mg/L representing 76.4% reduction in Chemical Oxygen Demand (COD), 2,900 NMP/100mL that represents 93.41% reduction of Thermotolerant Coliforms and 12.4 NTU that represents 80.11% reduction of turbidity.

Reduction of the pollutants concentration in the effluents of the fish canning industry using air nanobubbles, Callao [Reducción de la concentración de contaminantes en los efluentes de la industria de conservas de pescado utilizando nanoburbujas de aire, Callao]

The present investigation was carried out with the purpose of evaluating the reduction of pollutants in the effluents tested from the fish canning industry using air nanobubbles. The study was carried out on a laboratory scale using air nanobubble generator equipment. The results were reduced by 89.5% of total suspended solids (from 6180 mg/L to 645 mg/L), 76.5% of BOD5 (from 7350 mgO2/L to 1730 mgO2/L), 73.6% of COD (from 10356 mgO2/L to 2735 mgO2/L) and 79.4% of oils and fats (from 96.3 mg/L to 33.2 mg/L). It was concluded that the treatment using air nanobubbles can significantly reduce the concentration of the pollutants present in the effluents of the fish canning industry.

Magnetite nanoparticles for reduction of hexavalent chrome in soil of an industrial park, Cerro Colorado - Arequipa [Nanopartículas de magnetita para reducción de cromo hexavalente en suelo de un parque industrial, Cerro Colorado – Arequipa]

One of the most important contamination problems in receiving bodies due to industrial activities is the presence of chromium (VI). One way to reduce the aggressiveness of said contaminant is its reduction to the form of chromium (III). The investigation determined the efficiency of magnetite nanoparticles in the treatment of soil contaminating with chromium (VI), to reduce it to chromium (III) of an Industrial Park at the district Cerro Colorado, province and department of Arequipa.22 samples of 1 kg of soil were taken, then homogenized according to the extraction distances, considering at the end only 3 samples called “Shore”, “6 Meters” and “9 Meters”, whose concentrations were: 146 mg / kg, 126 mg / kg and 67 mg / kg of Cr (VI) respectively. These samples were subjected to 3 treatments (T1, T2 and T3) with 3 repetitions each using 15, 30 and 45 grams doses of Magnetite nanoparticles for three weeks. At the end of the treatment using the EPA 3060 method, the Chrome (VI) analysis was performed. The 3 treatments “T1”, “T2” and “T3”, had significant differences for the final concentrations of Hexavalent Chromium in the soil; but it was in Treatment 3 in the soil samples "Shore", "6 Meters" and "9 Meters", where a greater effect was achieved in the reduction of Cr (VI) to Chromium (III) with an efficiency of 99.96%, 99.93% and 99.93% respectively, 45 grams of magnetite nanoparticles were used for this treatment.

Analytical Electron Microscopy of Silicon Nitride Nanostructures Synthesized from the Vapor Phase

Silicon nitride, Si3N4 is a covalent compound with excellent physical and chemical properties such as corrosion resistance, low-specific weight and good thermal conductivity at ambient and elevated temperatures. Such properties are very attractive in application as advanced ceramics and in semiconductor devise [1]. Nano sized amorphous silicon nitride powders were synthesized at 300 °C by precipitation from the vapor phase reaction of SiCl4 and NH3 and Ar as carrier gas. Solid ammonium halogenide is formed as by-product, in addition to silicon nitride powder.

Application of air nanobubbles in washing sewage of a Soft drink bottling plant [Aplicación de nanoburbujas de aire en aguas residuales de lavado de una Embotelladora de Bebidas Carbonatadas]

The research’s purpose was to apply air nanobubbles in washing sewage of a soft drink bottling plant. The methodology used was pre-experimental and applied. The air nanobubbles were applied in the 3 samples of 20 liters of washing sewage of a Soft drink bottling plant, from which 2 samples were extracted: one at 45 minutes and another at 90 minutes after starting treatment. The results showed that air nanobubbles reduced the concentration of: conductivity by 8.4% (from 2500 mS/cm to 2290 mS/cm), turbidity by 71.97% (from 152 NTU to 42.6 NTU), BOD5 by 99.89% (from 1892.7 mg/L to 1.9 mg/L) and COD in 99.13% (from 3681 mg/L to 32 mg/L).

Reduction of dielectric oil present in Fuller soil by applying Micro-nanobubbles of air at laboratory level

The present research consisted of reducing the presence of dielectric oil in fuller ground by using air micro-nanobubbles at laboratory level. Weighed 3 containers 500 grams of soil with dielectric oil in each. After 48 hours the treatment with air micro-nanobubbles was carried out. It was taken to the laboratory to measure the parameters: pH, CE, mv and T in 30, 60, and 90 minutes after total hydrocarbons were analyzed. The best result was sample number 3 with a time of 90 minutes with a 59.6% reduction in the presence of dielectric oil, considered significant for the research work.

Treatment of wastewater with chloroform from an environmental laboratory using air micro-nanobubbles

In the investigation, the wastewater was treated with chloroform generated in an environmental laboratory by means of micro-nano air bubbles. For the preliminary analysis, 40 mL of sample were taken. Initial parameters such as pH, electrical conductivity, dissolved oxygen and temperature were analyzed. The treatments were in three times 20, 40 and 60 minutes and three runs were made. Finally, the final measurements were made, obtaining favorable results for the Chloroform parameter. The reduction was from 0.8 mg/L to 0.2 mg/L and the pH was improved from 4.69 to 6.85, thus determining that the Micro-nano bubble technology does reduce the concentrations of the contaminant Chloroform present in the water.