Bioremediation technology is one of the most profitable and sustainable strategies for remediating soils contaminated with hydrocarbons. This study focuses on assessing the influence of biostimulation and bioaugmentation with Pseudomonas fluorescens to contribute to the removal of total petroleum hydrocarbons (TPHs) of a soil. Laboratory studies were carried out (measurements of emitted CO2, surface tension, and residual TPH) to select the best bioaugmentation and biostimulation treatment. The sources of C, N, and P were glucose–yeast extract, NH4Cl–NaNO3, and K2HPO4–K3PO4, respectively. The effect of culture conditions on the reduction of TPH and respiratory activity was evaluated through a factorial design, 23, in a solid culture system. After 80 days of incubation, it was observed that treatments of yeast extract–NH4Cl–K2HPO4 (Y4) and glucose–NaNO3–K3PO4 (Y5) presented a higher level of TPH removal (20.91% and 20.00% degradation of TPH, respectively). Biostimulation favors the production of biosurfactants, indirectly measured by the change in surface tension in the soil extracts. The treatments Y4 and Y5 showed a lower change value of the surface tension (23.15 and 23.30 mN·m−1 at 25 °C). A positive correlation was determined between the change in surface tension and the removal of TPH; hence there was a contribution of the biosurfactants produced to the removal of hydrocarbons.
The use of medicinal plants represents an alternative method for bacterial control due to their chemical compositions. This study’s objective was to determine the inhibitory capacity of Larrea tridentata extracts against microbial strains of clinical interest. Four extracts were prepared, their phytochemical profiles were determined, and their antioxidant capacities were quantified. Additionally, the minimum concentrations of hemolysis were determined using human blood erythrocytes. For the extracts’ growth inhibitory capacity, six bacterial and two fungal strains were evaluated using the disk diffusion test. Commercial medications specific for each strain were used as controls. The ethanolic extracts registered the greatest diversity of metabolites related to antibacterial activity. The inhibitory activities of the ethanolic extract and the Cedax® control were similar for Enterococcus faecalis. A principal component analysis was performed with X2 and ANOVA tests to identify the relationships and the effects of the extracts on bacterial inhibition, obtaining p > 0.05 with a confidence level of 95%. This research highlights the potential of L. tridentata extracts as an alternative treatment and to mitigate the growing problem of resistance to traditional antibiotics.
16 February 2014 in Journal of Applied Mathematics
Today the knowledge of physical parameters of a basin is essential to know adequately the rainfall-runoff process; it is well known that the specific characteristics of each basin such as temperature, geographical location, and elevation above sea level affect the maximum discharge and the basin time response. In this paper a physically based model has been applied, to analyze water balance by evaluating the volume rainfall-runoff using SHETRAN and hydrometric data measurements in 2003. The results have been compared with five ETp different methodologies in the Querétaro river basin in central Mexico. With these results the main effort of the authorities should be directed to better control of land-use changes and to working permanently in the analysis of the related parameters, which will have a similar behavior to changes currently being introduced and presented in observed values in this basin. This methodology can be a strong base for sustainable water management in a basin, the prognosis and effect of land-use changes, and availability of water and also can be used to determine application of known basin parameters, basically depending on land-use, land-use changes, and climatological database to determine the water balance in a basin.
Secondary metabolites (SM) in plants play crucial pharmacological, ecological, and nutritional roles for humans, wildlife, and livestock. Environmental Heterogeneity (EH) encompasses the variability of biotic and abiotic factors that influence biological responses of plant species. Advancements in remote sensing have enhanced the ability to assess plant functional traits more affordably and comprehensively by integrating spectral reflectance data with detailed plant metabolomics. However, studies investigating the relationship between EH—quantified using Rao’s Q heterogeneity index from remote sensing data—and SM diversity remain limited. Here, we present the first report demonstrating that the biotic component of EH, measured as Rao’s Q, is positively associated with SM diversity in mesquite pod extracts—higher Rao’s Q values correspond to greater SM diversity. Generalized additive models (GAMs) revealed that Rao’s Q contributed the most explanatory power, accounting for 21.2% of the deviance, compared to pod weight (13.7%) and pod length (2.03%). However, only the relationship between Rao’s Q and SM diversity was statistically significant (p = 0.029). The Rao’s Q index derived from remote sensing serves as a scalable proxy for identifying SM hotspots, facilitating the targeted discovery of regions with high pharmacological or nutritional value.
Synthetic plastic impacts the environment due to its slow degradation and the generation of microplastics, driving the development of bioplastics. This study evaluated the use of bagasse fiber combined with corn and potato starch to improve the physical and mechanical properties of bioplastics. Five bioplastic mixtures (Am1 to Am5) were prepared with corn starch, glycerin, acetic acid, maleic anhydride, and agave bagasse. Am1 was prepared without bagasse, and the others were prepared with different amounts of bagasse (0, 10, 30, 50, and 70 g). Bioplastics made from potato starch (Ap1 to Ap5) were also produced under the same conditions and were assessed using the thermogravimetric (TGA) and scanning electron microscopy (SEM) tests. Analysis of variance showed significant differences (p < 0.001) in the moisture, Young’s modulus, and stress of the bioplastics. The corn-based bioplastics exhibited lower moisture values (7.26% and 5.51%) compared to the potato-based ones (9.68% to 8.89%). Young’s modulus and stress increased in the corn-based (Am5 = 4.59 MPa) and potato-based (Ap5 = 3.53 MPa) bioplastics with higher amounts of bagasse. Furthermore, TGA and SEM revealed the surface morphology and the effects of processing, and based on their results, it was found that agave bagasse improved the mechanical and thermal properties of bioplastics, especially corn-based ones, suggesting its potential as a material with a lower environmental impact.
Neltuma spp. are an important resource in arid and semiarid ecosystems of the country and serve, among other purposes, as an economic source of food for livestock. By analyzing the bromatological composition and in vitro fermentation of pods in three regions of the state of Zacatecas, Mexico, the viability as a food alternative in sheep is sought. Twenty-seven pod samples were collected from nine points in each region of the state. The samples were obtained when the pods were in the immature stage. The bromatological analysis of the pods was conducted and mathematical equations were used to calculate the megacalories per kilogram provided by these fruits. Statistical analysis was performed using Spearman’s correlation coefficient. Bromatological analysis showed that crude protein averaged 20.86 ± 1.37% in the central region, while non-fiber carbohydrates averaged 26.78 ± 1.32% in the southern region. Neltuma spp. pods demonstrate potential as an alternative feed for sheep, provided that an adequate diet is formulated, since they present acceptable levels of protein, carbohydrates and fiber. It is recommended to consider the state of maturity of the pods when incorporating them into the diet of sheep.