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1.
Chem Biodivers ; 21(7): e202400667, 2024 Jul.
Article in English | MEDLINE | ID: mdl-38935347

ABSTRACT

Monoacylglycerols are eco-friendly and inexpensive emulsifiers with a range of applications. The traditional synthetic route is not eco-friendly, while enzymatic catalysis offers milder reaction conditions and higher selectivity. However, its application still is limited due to the costs. In this context, endophytic fungi can be source to new biocatalysts with enhanced catalytic activity. Based on this perspective, the aim of this study was perform the synthesis of MAG's through transesterification reactions of solketal and different vinyl esters, using crude and immobilized lipolytic extracts from the endophytic fungi Stemphylium lycopersici, isolated from Humiria balsamifera. The reactions were conducted using 100 mg of biocatalyst, 1 mmol of substrates, 9 : 1 n-heptane/acetone, at 40 °C, 200 rpm for 96 h. In the reactions using the ILE and stearate, laureate and decanoate vinyl esters it was possible to obtain the correspondent products with conversion rates of 52-75 %. Also, according to the structure drivers used in MCM-48 synthesis, different morphologies and conversions rates were observed. Employing [C16MI] Cl, [C14MI] Cl and [C4MI] Cl, the 1-lauroyl- glycerol conversion was 36 %, 79 % and 44 %, respectively. This is the first work involving the immobilization of an endophytic fungi and its utilization as a biocatalyst in the production of MAG's.


Subject(s)
Biocatalysis , Monoglycerides , Monoglycerides/chemistry , Monoglycerides/metabolism , Porosity , Ascomycota/metabolism
2.
J Food Sci Technol ; 60(1): 84-91, 2023 Jan.
Article in English | MEDLINE | ID: mdl-36618061

ABSTRACT

An important factor resulted from the ascension of the milk and milk-based by-products production is many effluents directly released into the environment. The main objective of this study was to evaluate the efficiency of the combination of the chemical coagulation, with ferric chloride as a coagulant, and the membrane separation processes (MSP) and reverse osmosis (RO) processes in the treatment of effluents from a powdered milk dairy industry. To evaluate the effectiveness of the integration of these mechanisms, the characterization of the effluents was carried out through Total Nitrogen (Ntotal), Total Organic Carbon (TOC), Chemical Oxygen Demand (COD), color, pH, and turbidity analysis. Regarding the treatments with ferric chloride, the Ntotal removal was up to 55.7% (concentration of 1.2 g L- 1) and the color up to 50% (0.7 g L- 1). For the MSP and RO treatments, the color removal was up to 100% (1st RO), turbidity up to 100% (1st RO), COD up to 98.7% (3rd RO), and TOC up to 96.7% (3rd RO). Finally, the integration of the chemical coagulation and MSP processes was efficient for the treatment of dairy industry wastewater and provides the return of water in appropriate characteristics according to legislation.

3.
Food Sci Technol Int ; 29(3): 255-265, 2023 Apr.
Article in English | MEDLINE | ID: mdl-34939457

ABSTRACT

There are many blackberry cultivars in Brazil; however, the characteristics and applications of the Cherokee cultivar have not yet been widely studied. For this reason, this research investigated the behaviour of maltodextrin (MD), gum Arabic (GA), and pectin (PEC), as carriers combined in different proportions (20% MD, 15% MD + 5% GA, 15% MD + 5% PEC), on encapsulation of Cherokee blackberry pulp extract obtained by freeze-drying. The results of moisture content (2.73-3.36%), water activity (aw) (0.11-0.15), solubility (52.40-54.11%), hygroscopicity (17.59-21.11%), colour (hue 0.24-0.32), retention of anthocyanins (51.55-60.53%), total phenolic compounds (39.72-70.73 mg GAE/100g), antioxidant activity at 25 mg/mL (77.89-80.02%), IC50 (12.26-14.53), simulated in vitro digestion and morphology were discussed. Concerning morphology, blackberry powders had irregular structures and amorphous structures. Comparatively, the best results were obtained for MD-GA. MD-GA presented the highest content of phenolic compounds (70.73 ± 1.84 mg GAE/100g) and antioxidant activity (80.02%), as well as the lowest IC50 value (12.26). In general, all powders showed an increase in phenolic compounds during in vitro digestion, because of the pH conditions and digestive enzymes present in the simulated digestive fluid. This result shows that the wall material provides protection, since the blackberry rich extract (RE) showed degradation of phenolic compounds in in vitro digestion. In this sense, freeze-drying is a suitable technique for the encapsulation of Cherokee blackberry pulp extract.


Subject(s)
Gum Arabic , Rubus , Gum Arabic/chemistry , Antioxidants/chemistry , Rubus/chemistry , Brazil , Pectins , Anthocyanins/chemistry , Drug Compounding/methods , Phenols/chemistry
4.
ACS Omega ; 3(11): 16074-16080, 2018 Nov 30.
Article in English | MEDLINE | ID: mdl-31458245

ABSTRACT

In this work, the use of ultrasound energy for chromium removal from residual tannery leather was investigated. The following parameters were evaluated: complexation temperature (60-90 °C), chromium/complexant molar ratio (1:0 to 1:6), complexation time (30-120 min), washing steps (1-14), washing temperature (25-80 °C), and washing time (1-10 min). For all evaluated conditions, chromium removal was monitored by flame atomic absorption spectrometry. The residual tannery leather after different extraction strategies were characterized using a scanning electron microscopy. For the proposed method, the optimized conditions were: 3 g of residual tannery leather to be treated, 100 mL of extraction solution (chromium/complexant molar ratio of 1:3), at 80 °C and 30 min of sonication. To complete the chromium removal, only five washing cycles (50 mL of water at 50 °C) of 3 min were required. Using these conditions, a chromium removal higher than 98% was achieved. Under the same reaction conditions, the results were compared with mechanical stirring (100 rpm), which allowed observing the significant effects of ultrasound for chromium removal. Comparing to the conventional method, the total time of the process (including extraction and washing steps) was decreased from 150 to 45 min and the water volume for the washing was reduced from 450 to 250 mL. Therefore, the proposed ultrasound-assisted process can be considered as a suitable alternative for chromium removal from residual tannery leather.

5.
Environ Technol ; 38(23): 2928-2938, 2017 Dec.
Article in English | MEDLINE | ID: mdl-28088876

ABSTRACT

The separation of Jatropha curcas oil from azeotropes of ethyl alcohol-n-hexane and isopropyl alcohol-n-hexane using ceramic membranes with different cutoffs (5, 10 and 20 kDa) is presented. The mass ratios of oil:azeotropes (O:S) studied were 1:3 for feeding pressures of 0.1, 0.2 and 0.3 MPa, and 1:1 for the feeding pressure of 0.1 MPa. Isopropyl alcohol was the best solvent for the membranes conditioning to permeate n-hexane (240 kg/m2 h). In the separation of J. curcas oil and azeotropes of solvents, both membranes showed oil retention and total flux decreases with time. Overall, the lowest decrease in the retentions was reached in the 5 kDa membrane, while the lowest decrease in the total flux was reached in the 20 kDa. In the separation of oil and ethyl alcohol-n-hexane azeotrope, the best retention at 60 min of the process was equal to 17.3 wt% in the 20 kDa membrane at 0.3 MPa and O:S ratio equalled to 1:3. In this condition, the total permeate flux was 17.5 kg/m2 h. Different retentions and permeabilities are provided when changing the O:S ratio, the feeding pressure and the molecular weight cutoff of membranes.


Subject(s)
Ceramics/chemistry , Chemical Fractionation/methods , Jatropha/chemistry , Plant Oils/isolation & purification , Solvents/chemistry , 2-Propanol/chemistry , Hexanes/chemistry , Membranes, Artificial , Plant Oils/chemistry
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