Kinetic, Thermodynamic, Physicochemical, and Economical Characterization of Pectin from Mangifera indica L. cv. Haden Residues.

The effect of temperature (60, 70, 80, and 90 °C) and time (30, 45, 60, 75, and 90 min) on citric acid extraction of Haden mango (Mangifera indica L. cv. Haden) peel pectin was evaluated in the present study. In order to obtain a better understanding of both the extraction process and the characteristics of the pectin (obtained from an agro-industrial waste) for a future scaling process, the following characterizations were performed: (1) Kinetic, with the maximum extraction times and yields at all evaluated temperatures; (2) thermodynamic, obtaining activation energies, enthalpies, entropies, and Gibbs free energies for each stage of the process; (3) physicochemical (chemical analysis, monosaccharide composition, degree of esterification, galacturonic acid content, free acidity, Fourier-transform infrared spectroscopy, thermogravimetric and derivative thermogravimetric analyses); and (4) economical, of the pectin with the highest yield. The Haden mango peel pectin was found to be characterized by a high-esterified degree (81.81 ± 0.00%), regular galacturonic acid content (71.57 ± 1.26%), low protein (0.83 ± 0.05%) and high ash (3.53 ± 0.02%) content, low mean viscometric molecular weight (55.91 kDa), and high equivalent weight (3657.55 ± 8.41), which makes it potentially useful for food applications.

Production of hydrocarbon-degrading microorganisms using agricultural residues of Mangifera indica L. and Carica papaya as carbon source.

The aim of the present study was to evaluate the potential of oils from agricultural residues, such as Mangifera indica L. (mango) and Carica papaya (papaya) from the Papaloapan region, Mexico, as a carbon source for the production of hydrocarbon-degrading (hydrocarbonoclastic) microorganisms in an airlift bioreactor via a common metabolic pathway for hydrocarbons and fatty acids. Biomass growth and carbon source uptake were measured using optical density and gas chromatography, respectively. Gompertz, logistic, and Von Bertalanffy mathematical models were used to obtain kinetic parameters such as the lag phase, maximum specific growth, and consumption rate. The hydrocarbonoclastic consortium was able to grow using papaya (6.09 ± 0.23 g L-1) and mango (2.59 ± 0.30 g L-1) oils, which contain certain antibacterial fatty acids. Differences observed in maximum specific growth and consumption rates indicate that, although mango oil was consumed faster (0.33 day-1 for mango and 0.25 day-1 for papaya), papaya oil provided a higher rate of biomass production per microorganism (0.24 day-1 for mango and 0.44 day-1 for papaya). Additionally, the consortium was able to consume 13 g L-1 diesel as a sole carbon source and improve its maximum specific consumption rate following growth using the oils. Furthermore, the maximum specific growth rate was decreased, indicating a change in the consortium capabilities. Nevertheless, agricultural waste oils from the Papaloapan region can be used to cultivate hydrocarbonoclastic microorganisms. The present study creates the possibility of investigating carbon sources other than hydrocarbons for the production of hydrocarbonoclastic microorganisms.