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Facial palsy is one of the most frequent mononeuropathies expressed in muscular weakness. The condition is produced by lesions in the seventh cranial nerve that causes esthetic, functional, and psychosocial alterations. The disorder has a qualitative diagnosis, and as a consequence, it does hinder the disease timely monitoring. As time is a key factor for the patient’s recovery, we developed a system capable to quantify the condition and/or damage in the seventh cranial nerve. It allows us to provide the best treatment available that offers the best response to each patient. To know the seventh cranial nerve state is possible due to the connections between whole muscular system and neurons. The system quantifies the muscles activity and displays the differential information of both hemifaces. Our proposal features a mask in which an array of sensors is placed across the frontal, zygomatic minor, risorio, zygomatic major muscles of each hemiface. The data collected are analyzed and displayed in a user-friendly interface.

Two bacterial strains able to produce polyhydroxyalkanoates (PHAs) from a wide variety of pure carbon sources (dextrose, xylose, sucrose, lactose and glycerol) were isolated from forest soils and identified as Achromobacter mucicolens and Stenotrophomonas rhizophila. Achromobacter mucicolens also produced poly(3-hydroxybutyrate) (PHB) from different wastes (cheese whey, molasses, agave bagasse hydrolysate, nejayote and mango waste pulp). Stenotrophomonas rhizophila, produced the copolymer poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (PHB-co-HV) from glycerol (7·7 mol% of HV), and from sucrose with addition of propionic or valeric acid (4·5 and 25 mol% of HV, respectively). The copolymers presented a lower melting point (145, 156 and 127°C) and crystallinity (23, 26 and 16%) than PHB. The maximum biopolymer accumulation (PHB) for each strain growing in pure carbon source was as follows: 31·3 g per 100 g dry cell weight (DCW) for A. mucicolens from xylose; and 13·7 g per 100 g DCW for S. rhizophila from sucrose. Regarding the waste carbon sources, the highest PHB accumulation was obtained from agave bagasse hydrolysate (20·4 g per 100 g DCW) by A. mucicolens. The molecular weights of the biopolymers obtained ranged from 200 to 741 kDa. SIGNIFICANCE AND IMPACT OF THE STUDY: The economic cost of the carbon source for the culture of polyhydroxyalkanoates (PHAs)-producing microorganisms is one of the main process limitations. Therefore, it is vital to find versatile microorganisms able to grow and to accumulate homo and copolymers of PHAs from low-cost substrates. In this research, we report two bacterial strains that produce poly(3-hydroxybutyrate), poly(3-hydroxybutyrate-co-3-hydroxyvalerate) or both from at least five pure and five waste carbon sources. These results, by such bacterial strains have not been reported, especially the production of copolymer from glycerol without addition of precursors by Stenotrophomonas rhizophila and the production of PHB from xylose and agave bagasse hydrolysate by Achromobacter mucicolens.

A stoichiometric model for Saccharomyces cerevisiae is reconstructed to analyze the continuous fermentation process of agave juice in Tequila production. The metabolic model contains 94 metabolites and 117 biochemical reactions. From the above set of reactions, 93 of them are linked to internal biochemical reactions and 24 are related to transport fluxes between the medium and the cell. The central metabolism of S. cerevisiae includes the synthesis for 20 amino-acids, carbohydrates, lipids, DNA and RNA. Using flux balance analysis (FBA), different physiological states of S. cerevisiae are shown during the fermentative process; these states are compared with experimental data under different dilution rates (0.04-0.12 h$ ^{-1} $). Moreover, the model performs anabolic and catabolic biochemical reactions for the production of higher alcohols. The importance of the Saccharomyces cerevisiae genomic model in the area of alcoholic beverage fermentation is due to the fact that it allows to estimate the metabolic fluxes during the beverage fermentation process and a physiology state of the microorganism.

Bacterial cellulose (BC) is a high value-added nano-structured biopolymer with important biomedical applications. Its biosynthesis from waste carbon sources might modify BC structure and properties, thus Mango pulp waste (MPW) was evaluated as an alternative culture medium for its production by the bacteria Komagataeibacter xylinus. The use of MPW could also decrease BC cost since the use pure sugars for its obtaining is expensive. The effect of different nitrogen sources and buffer addition to MPW-medium on the polymer yield was also investigated. Using MPW and yeast extract as a nitrogen source, a production of 6.32 g/L of BC was obtained after 16 days of static culture. BC was characterized by SEM, XRD, TGA, FTIR and Water holding capacity (WHC). Chemical structure and thermal degradation of BC produced from MPW were similar to those of BC obtained with pure sugars (350°C). Crystallinity index of BC produced in mango-based medium was lower (62.7 % vs. 77.2 %); WHC was higher (108.7 % vs. 88.7 %); and fiber diameter was smaller (98.8 nm vs. 50.6 nm).

Hydrogels have become a key class of materials that could be used in several fields such as biotechnology and nanotechnology. They can be classified as natural and synthetic according to their base material. Poly (ethylene glycol) diacrylate (PEG-DA) is a synthetic hydrogel, which can be considered for a wide variety of applications in the fields of biomedical research, drug delivery, tissue engineering and scaffolds among others. For these reasons, the design and the use of droplet-based microfluidics devices are important for the production of these microparticles of PEG-DA, which have gained popularity. In this research, two microfluidics devices are analyzed; a microfluidic T-junction device and a microfluidic flow focusing device. These devices are fabricated by using poly (dimethyl siloxane). The research is based on the flow rate variation of the dispersed phase (PEG-DA solution) and the continuous phase (Mineral oil) to establish the best conditions to the formation of the microparticles. Results show that the variation of the continuous phase flow rates and the geometry have an influence in the droplet formation mechanism. In addition, it is interesting to observe the flow rates in which the droplet formation occurs and which it does not.

Photopolymerized microparticles are made of biocompatible hydrogels like Polyethylene Glycol Diacrylate (PEGDA) by using microfluidic devices are a good option for encapsulation, transport and retention of biological or toxic agents. Due to the different applications of these microparticles, it is important to investigate the formulation and the mechanical properties of the material of which they are made of. Therefore, in the present study, mechanical tests were carried out to determine the swelling, drying, soluble fraction, compression, cross-linking density (Mc) and mesh size (ξ) properties of different hydrogel formulations. Tests provided sufficient data to select the best formulation for the future generation of microparticles using microfluidic devices. The initial gelation times of the hydrogels formulations were estimated for their use in the photopolymerization process inside a microfluidic device. Obtained results showed a close relationship between the amount of PEGDA used in the hydrogel and its mechanical properties as well as its initial gelation time. Consequently, it is of considerable importance to know the mechanical properties of the hydrogels made in this research for their proper manipulation and application. On the other hand, the initial gelation time is crucial in photopolymerizable hydrogels and their use in continuous systems such as microfluidic devices.

The facial nerve is an array that encompasses motor and sensory fibers. It is one of the most common cranial nerves involved in disorders that considers congenital, traumatic, inflammatory and neoplastic disorders. Facial palsy is a common disease that results from the abnormal state of the facial nerve. In order to understand the full behavior, a quantification method for facial palsy is developed. The method that we propose uses the muscle trajectory information in order to perform a comparison between the right and left side of the face starting from the sagittal plane. To obtain such information, we developed an algorithm that will read a sensor array distributed across the face in order to read the state of the muscle in real time. Moreover, a statistical analysis is performed allowing us to know the state of the facial nerve. Accurate facial palsy measurement are key in the disorder treatment. According to the results found by our system, healthy faces must show a high correlation as well as a large standard deviation, correlation coefficient and a statistical mean.

In this research it was studied the nutrients removal of NH 3 -N, NO 3 -N and PO 4 -P from municipal wastewater, using Chlorella vulgaris , Pseudomonas putida , Bacillus cereus and the artificial consortium between them. The objective is to analyze the performance of these microorganisms and their consortium, which has not been previously studied for nutrient removal in municipal wastewater. A model wastewater was prepared simulating the physicochemical characteristics found at the wastewater plant in Chapala, Mexico. Experiments were carried out without adding an external carbon source. Results indicate that nutrient removal with Chlorella vulgaris was the most efficient with a removal of 24.03% of NO 3 -N, 80.62% of NH 3 -N and 4.30% PO 4 -P. With Bacillus cereus the results were 8.40% of NO 3 -N, 28.80% of NH 3 -N and 3.80% of PO 4 -P. The removals with Pseudomonas putida were 2.50% of NO 3 -N, 41.80 of NH 3 -N and 4.30% of PO 4 -P. The consortium of Chlorella vulgaris - Bacillus cereus - Pseudomonas putida removes the 29.40% of NO 3 -N, 4.2% of NH 3 -N and 8.4% of PO 4 -P. The highest biomass production was with Bacillus cereus (450 mg/l) followed by Pseudomonas putida (444 mg/l), the consortium (205 mg/l) and Chlorella vulgaris (88.9 mg/l). This study highlights the utility of these microorganisms for nutrient removal in wastewater treatments.

Anthropogenic activities have increased the amount of urban wastewater discharged into natural aquatic reservoirs containing a high amount of nutrients such as phosphorus (Pi and PO 4 &minus, 3 ), nitrogen (NH 3 and NO 3 &minus, ) and organic contaminants. Most of the urban wastewater in Mexico do not receive any treatment to remove nutrients. Several studies have reported that an alternative to reduce those contaminants is using consortiums of microalgae and endogenous bacteria. In this research, a genome-scale biochemical reaction network is reconstructed for the co-culture between the microalga Chlorella vulgaris and the bacterium Pseudomonas aeruginosa. Metabolic Pathway Analysis (MPA), is applied to understand the metabolic capabilities of the co-culture and to elucidate the best conditions in removing nutrients. Theoretical yields for phosphorus removal under photoheterotrophic conditions are calculated, determining their values as 0.042 mmol of PO 4 &minus, 3 per g DW of C. vulgaris, 19.43 mmol of phosphorus (Pi) per g DW of C. vulgaris and 4.90 mmol of phosphorus (Pi) per g DW of P. aeruginosa. Similarly, according to the genome-scale biochemical reaction network the theoretical yields for nitrogen removal are 10.3 mmol of NH 3 per g DW of P. aeruginosa and 7.19 mmol of NO 3 &minus, per g DW of C. vulgaris. Thus, this research proves the metabolic capacity of these microorganisms in removing nutrients and their theoretical yields are calculated.

Anthropogenic activities have increased the amount of urban wastewater discharged into natural aquatic reservoirs confining in them a high amount of nutrients and organics contaminants. Several studies have reported that an alternative to reduce those contaminants is using consortiums of microalgae and endogenous bacteria. In this research, a genome-scale biochemical reaction network is reconstructed for the co-culture between the microalga Chlorella vulgaris and the bacterium Pesudomonas aeruginosa. Metabolic Pathway Analysis (MPA), is applied to understand the metabolic capabilities of the co-culture and to elucidate the best conditions in removing nutrients such as Phosphorus (inorganic phosphorous and phosphate) and Nitrogen (nitrates and ammonia). Theoretical yields for Phosphorus removal under photoheterotrophic conditions are calculated, determining their values as 0.042 mmol of PO4/ g DW of C. vulgaris, 19.53 mmol of inorganic Phosphorus /g DW of C. vulgaris and 4.90 mmol of inorganic Phosphorus/ g DW of P. aeruginosa. Similarly, according to the genome-scale biochemical reaction network the theoretical yields for Nitrogen removal are 10.3 mmol of NH3/g DW of P. aeruginosa and 7.19 mmol of NO3 /g DW of C. vulgaris. Thus, this research proves the metabolic capacity of these microorganisms in removing nutrients and their theoretical yields are calculated.

In this research removal of NH

An Asymptotic Observer (AO) is proposed to analyze and to study biochemical transient-state systems. In agreement with a rigorous conservation analysis, the AO is able to estimate unmeasured internal metabolite concentrations without knowledge of the kinetic model and the initial condition of the state variables of the metabolic network. The AO methodology is applied in the pentose phosphate pathway of Saccharomyces cerevisiae. Results demonstrated good accuracy and stability properties of AO for rebuilding the unknown metabolic information under transient conditions of biochemical networks. According to its features, AO could become a useful tool to better understand biochemical systems in dynamic state.

Benzene, toluene, and o-xylene (BTX) degradation by immobilized Pseudomonas putida F1 of postconsumer agave-fiber/polymer foamed-composites (AFPFC) and suspended cultures was studied under controlled conditions. Analyses using FTIR-ATR and SEM showed that P. putida F1 adhered onto the composite surface and developed a biofilm. In this sense, the AFPFC were successfully used as a support for bacterial immobilization. Both systems, immobilized and suspended cells of P. putida F1, were able to completely degrade benzene and toluene from initial concentrations of 15, 30, 60, and 90 mg l−1. An inhibitory effect of the intermediary catechol from benzene degradation was observed in suspended cultures but it was not presented in the immobilized system. The degradation of o-xylene was partially accomplished in both systems. The Monod equation was used to model the experimental data obtained from the biodegradation kinetics, and they were adequately described with this model.

Biosynthesis of poly(3-hydroxybutyrate) (PHB) from raw starch as the carbon source by the polysaccharide-digesting bacteria Saccharophagus degradans was investigated in a fed-batch culture. The production and properties of the PHB synthesized from starch were compared to those obtained using glucose as carbon source. In fed-batch cultures, S. degradans accumulated 21.35 and 17.46% of PHB, using glucose or starch as carbon source, respectively. The physical properties of the biopolymer produced from each carbon source were similar between them. Molecular mass, melting temperature and heat of fusion were 54.23 kDa, 165.61°C and 59.59 J/g, respectively, using glucose; and 57.07 kDa, 174.31°C and 67.66 J/g, respectively, using starch. This is the first work describing the capability of S. degradans to utilize raw starch as the sole carbon source for the production of PHB.

The capability of Halobacterium sp. NRC-1 to synthesize carboxyl ester hydrolases was investigated, and the effect of physicochemical conditions on the growth rate and production of esterases was evaluated. The haloarchaeon synthesized a carboxyl ester hydrolase, confirming the genomic prediction. This enzymatic activity was intracellularly produced as a growth-associated metabolite. Esterase activity was assayed using different p-nitrophenyl-esters and triacyl-glycerides, which showed a preference for hydrolyzing tributyrin. The archaeal growth rate and esterase production were significantly influenced by the pH and the NaCl concentration. An interaction effect between temperature and NaCl was also seen. The maximal growth rate and esterase production found for Halobacterium sp. NRC-1 were 0.136 h(-1) (at 4.2 M NaCl, pH 6 and 44 degrees C) and 1.64 U/l (at 4.6 M NaCl, pH 6 and 30 degrees C), respectively. Furthermore, the effects of NaCl concentration, pH and temperature on enzyme activity were studied. Two maximal esterase activities were elucidated from the intracellular crude extract when it was incubated at different NaCl concentrations (1 M and 5 M) and at different pHs (6 and 7.5). This is the first report that shows experimentally the synthesis of carboxyl ester hydrolases by Halobacterium sp. NRC-1. This enzyme was found to be extremely halophilic (5 M NaCl) and thermophilic (80 degrees C), making it very interesting for future investigations in non-aqueous biocatalysis.

The marine bacterium Saccharophagus degradans was investigated for the synthesis of polyhydroxyalkanoates (PHAs), using glucose as the sole source of carbon in a two-step batch culture. In the first step the microorganism grew under nutrient balanced conditions; in the second step the cells were cultivated under limitation of nitrogen source. The biopolymer accumulated in S. degradans cells was detected by Nile red staining and FT-IR analysis. From GC-MS analysis, it was found that this strain produced a homopolymer of 3-hydroxybutyric acid. The cellular polymer concentration, its molecular mass, glass transition temperature, melting point and heat of fusion were 17.2+/-2.7% of dry cell weight, 54.2+/-0.6 kDa, 37.4+/-6.0 degrees C, 165.6+/-5.5 degrees C and 59.6+/-2.2 J g(-1), respectively. This work is the first report determining the capacity of S. degradans to synthesize PHAs.

The production and characterization of polyhydroxyalkanoic acids (PHAs) from glucose in Pseudomonas aeruginosa ATCC 9027 is described. We determined that the synthesis of PHAs was not due to a complete lack of nitrogen source, as previously reported for other microorganisms. The synthesis of PHAs was observed during exponential growth and it depended on the carbon/nitrogen ratio in the culture. More significantly, the specific PHA accumulation rate in this phase was higher than that observed in the storage phase. This phenomenon was a consequence of higher extracellular production rates of gluconate and 2-ketogluconate detected during the storage phase. Therefore, the production of those acids decreased the synthesis of PHAs in P. aeruginosa. The maximum percentage of PHA accumulation obtained was 10.8% of the cell dry matter when all the glucose was consumed. The monomer composition of this PHA consisted only of saturated 3-hydroxy fatty acids (octanoic, decanoic, and dodecanoic acids) as shown by gas chromatography – mass spectroscopy and nuclear magnetic resonance analyses, where 3-hydroxydecanoic acid was the main component because of the high affinity of its PhaC synthase for this monomer. The physical properties of this PHA were determined by differential scanning calorimetry and gel permeation chromatography.

In this work, an optimization method is implemented in an anaerobic digestion model to estimate its kinetic parameters and yield coefficients. This method combines the use of advanced state estimation schemes and powerful nonlinear programming techniques to yield fast and accurate estimates of the aforementioned parameters. In this method, we first implement an asymptotic observer to provide estimates of the non-measured variables (such as biomass concentration) and good guesses for the initial conditions of the parameter estimation algorithm. These results are then used by the successive quadratic programming (SQP) technique to calculate the kinetic parameters and yield coefficients of the anaerobic digestion process. The model, provided with the estimated parameters, is tested with experimental data from a pilot-scale fixed bed reactor treating raw industrial wine distillery wastewater. It is shown that SQP reaches a fast and accurate estimation of the kinetic parameters despite highly noise corrupted experimental data and time varying inputs variables. A statistical analysis is also performed to validate the combined estimation method. Finally, a comparison between the proposed method and the traditional Marquardt technique shows that both yield similar results; however, the calculation time of the traditional technique is considerable higher than that of the proposed method.

The present study was conducted to investigate the capability of Haloarcula marismortui to synthesize esterases and lipases, and the effect of physicochemical conditions on the growth and the production of esterases and lipases. Finally, the effect of NaCl concentration and temperature on esterase and lipase activities was studied using intracellular crude extracts. In order to confirm the genomic prediction about the esterase and lipase synthesis, H. marismortui was cultured on a rich medium and the crude extracts (intra- or extracellular) obtained were assayed for both activities using p-nitrophenyl esters and triacylglycerides as substrates. Studies on the kinetics of growth and production of esterase and lipase of H. marismortui were performed, reaching a maximum growth rate of 0.053 h(-1) and maximal productions of intracellular esterase and lipase of 2.094 and 0.722 U l(-1) using p-nitrophenyl valerate and p-nitrophenyl laurate, respectively. Both enzymes were produced as growth-associated metabolites. The effects of temperature, pH, and NaCl concentration on the growth rate and production of enzymes were studied by using a Box-Behnken response surface design. The three response variables were significantly influenced by the physicochemical factors and an interaction effect between temperature and NaCl concentration was also evidenced. The surface response method estimated the following maximal values for growth rate and productions of esterase and lipase: 0.086 h(-1) (at 42.5 degrees C, pH 7.4, and 3.6 mol l(-1) NaCl), 2.3 U l(-1) (at 50 degrees C, pH 7.5, and 4.3 mol l(-1) NaCl), and 0.58 U l(-1) (at 50 degrees C, pH 7.6, and 4.5 mol l(-1) NaCl), respectively. Esterases were active at different salt concentrations, showing two optimal activities (at 0.5 and 5 mol l(-1) NaCl), which suggested the presence of two different esterases. Interestingly, in the absence of salt, esterase retained 50% residual activity. Esterases and lipase activities were maximal at 45 degrees C and inactive at 75 degrees C. This study represents the first report evidencing the synthesis of esterase and lipase by H. marismortui.

Adhesion of Pseudomonas putida F1 onto agave-fiber/recycled-polyethylene foamed composites was studied under different controlled conditions. The adhesion process was analyzed in batch experiments controlling factors such as pH, contact time, temperature, initial biomass concentration and ionic strength; and was verified by scanning electron microscopy (SEM). The number of adhered bacteria after the experimental time was determined by difference between concentration of suspended cells in NaCl solution contained in two different Erlenmeyer flasks, one of the flasks with composite pellets and the other one without them. The concentration of cells in each flask was obtained using the serial dilution technique. Experimental data analysis showed that adsorption follows first-order kinetics. And it was further corroborated to be an irreversible process. For the first time, an equation is proposed here to predict the correlation between adhered bacteria and aqueous pH. In addition to the obvious reuse of waste material, these results suggested that agave-fiber/polymer foamed composites could be used as support for bacterial immobilization to be applied, among others in environmental processes such as bioremediation and biofiltration of gases with almost limitless possibilities.

En este trabajo se presenta una revisión bibliográfica que tiene como objetivo identificar y analizar alternativas de aprovechamiento del bagazo de Agave tequilana Weber var. Azul. Se proponen dos líneas de investigación para obtener productos de valor agregado a partir de este residuo: 1)utilización como fuente de carbono de bajo costo para la producción de biopolímeros y carbohidrasas, con bacterias celulolíticas del género Microbulbifer, Marinobacterium y Sagittula; 2)obtención de compuestos fenólicos a partir de la lignina presente en sus fibras. Se concluye, que el bagazo de agave tequilero es un material viable para ser usado como substrato en procesos fermentativos, por lo que existen grandes oportunidades de investigación para desarrollar procesos de bioconversión técnicamente factible, eficiente y económicamente atractivo