Hydrocarbons and other risks in a beekeeping area of México: the precautionary principle for prevention and biotechnology for remediation

The Yucatan Peninsula is the most important beekeeping region. However, the presence of hydrocarbons and pesticides violates the human right to a healthy environment twice over; it can affect human beings directly due to its toxicological characteristics, but it also constitutes a risk, not very well dimensioned, regarding the loss of biodiversity of the ecosystem via the impact on pollination. On the other hand, the precautionary principle obliges the authorities to prevent damage to the ecosystem that may be caused by the productive activity of individuals. Although there are studies that separately warn about the decrease of bees in the Yucatan due to industrial activity, this work has the novelty of presenting an intersectoral analysis of the risk that includes the soy industry, the swine industry and the tourist industry. The latter incorporates a new risk not considered until now, which is the presence of hydrocarbons in the ecosystem. Additionally, we can demonstrate that hydrocarbons, such as diesel and gasoline, should be avoided when using no genetically modified organisms (GMOs) in bioreactors. The objective of this work was to propose the precautionary principle around the risks in a beekeeping area and to propose biotechnology without using GMOs.

Oxygen and hydrocarbon volumetric transfer coefficients in the production of an oil-degrading bacterial consortium: emulsifying activity and surface tension in a bioreactor

Our work shows that in multiphase systems, it is more important to take into account the mass transfer of oil rather than that of just oxygen. The oxygen volumetric transfer coefficient is important in aerobic bioreactor design. However, in multiphase systems with non-soluble substrates, oil transfer can impose larger restrictions but is usually not considered. Emulsification and surface tension could play an important role due to effects on oil droplet size and interfacial transfer area. Petroleum oil and is derivates such as diesel can negatively affect living organisms. This study evaluated the effects of the volumetric transfer coefficients (kLa) of hydrocarbons and oxygen on the production of an oil-degrading consortium in an airlift bioreactor relative to emulsifying activity and surface tension, which play important roles in the biodegradation of non-soluble substrates such as diesel due to a combined mass transfer constraint. Our results showed a clear difference in kLa values, which ranged from 15 to 91 h-1 for oxygen and from 0 to 0.0014 h-1 for diesel. Most aerobic biodegradation studies focus on the oxygen volumetric transfer coefficient (kLaoxygen), but our results indicated that non-soluble constraints, such as the volumetric transfer coefficient of diesel (kLadiesel), could be more important. Additionally, d32diesel decreased as superficial gas velocity (Ug) increased. Lower Ug rates (0.15 cm s-1) resulted in higher values of d32diesel (0.38 cm-1), whereas higher Ug rates (2.7 cm s-1) resulted in lower values of d32diesel (0.21 cm-1) at the beginning of the cultivation.

The degradation of an aromatic organic compound by Aspergillus niger var tubingensis Ed8 produces metabolites that reduce Cr (VI)

Chromium Cr(VI) is a highly toxic environmental contaminant for any organism, its presence in the environment is mainly due to anthropogenic activities. The use of biotechnology has been implemented for the treatment of effluents contaminated with Cr(VI).Our working group has isolated several fungi and bacteria capable of removing Cr(VI) from the culture medium. Aspergillus niger var tubingensis Ed8 is a strain that can produce metabolites which reduce Cr (VI) to Cr (III). The objective of this work was to determine the effect of sodium salicylate on the growth of this strain and on the Cr(VI) reduction system, as well as to identify the metabolites that are produced from sodium salicylate. Our results show that the Culture medium containing sodium salicylate (20 mM) inhibits strain growth compared to the control condition (0 mM). However, it increases the specific reduction capacity of Cr (VI) red/mg Biomass in order of magnitude. Analysis of the culture medium corresponding to 48 h of incubation shows the presence of catechol and salicylate diminution. In addition, as a product of the enzymatic activity of a cell-free cellular extract, after 24 h of incubation, the consumption of salicylate is detected, as well as the presence of peaks corresponding to resorcinol and catechol. Our results show that it is possible to increase the Cr(VI) reducing capacity of the Ed8 strain, depending on the composition of the culture medium.

Bubble Column Bioreactor using native non-genetically modified organisms: a remediation alternative by hydrocarbon-polluted water from the Gulf of Mexico

Notwithstanding the benefits that oil provides as a source of energy, society also recognizes the environmental problems caused by its use. We evaluated eight coastal sites in the central area of the Gulf of Mexico. At these sites, 14 hydrocarbons were detected which belong to compounds formed by carbons ranging from C9 to C27. The hydrocarbons with the highest concentrations were n-nonane (3.07 ± 1.60 mg L−1), carbazole (0.93 ± 0.12 mg L−1) and benzo [a] pyrene (1.33 ± 0.71 mg L−1). The hydrocarbons found belong mostly to medium fraction hydrocarbons, which are mostly found in fuels such as diesel. Therefore, this fuel was used as a carbon source or substrate in bubble column bioreactors. The capacity of non-genetically modified organisms to degrade microbial hydrocarbons was evaluated using a mineral medium for a period of 14 days. Suspended solids increased from 0.8 to 2.94 g L−1. Diesel consumption was achieved in 12 days of operation.

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.

Effect of solvent polarity on the Ultrasound Assisted extraction and antioxidant activity of phenolic compounds from habanero pepper leaves (Capsicum chinense) and its identification by UPLC-PDA-ESI-MS/MS

Phenolic compounds are secondary metabolites involved in plant adaptation processes. The development of extraction procedures, quantification, and identification of this compounds in habanero pepper (Capsicum chinense) leaves can provide information about their accumulation and possible biological function. The main objective of this work was to study the effect of the UAE method and the polarity of different extraction solvents on the recovery of phenolic compounds from C. chinense leaves. Quantification of the total phenolic content (TPC), antioxidant activity (AA) by ABTS⁺ and DPPH radical inhibition methods, and the relation between the dielectric constant (ε) as polarity parameter of the solvents and TPC using Weibull and Gaussian distribution models was analyzed. The major phenolic compounds in C. chinense leaves extracts were identified and quantified by UPLC-PDA-ESI-MS/MS. The highest recovery of TPC (24.39 ± 2.41 mg GAE g^-1 dry wt) was obtained using MeOH (50%) by UAE method. Correlations between TPC and AA of 0.89 and 0.91 were found for both radical inhibition methods (ABTS⁺ and DPPH). The Weibull and Gaussian models showed high regression values (0.93 to 0.95) suggesting that the highest phenolic compounds recovery is obtained using solvents with "ε" values between 35 and 52 by UAE. The major compounds were identified as N-caffeoyl putrescine, apigenin, luteolin and diosmetin derivatives. The models presented are proposed as a useful tool to predict the appropriate solvent composition for the extraction of phenolic compounds from C. chinense leaves by UAE based on the "ε" of the solvents for future metabolomic studies.

Hydrocarbon Contamination Patterns in the Cenotes of the Mexican Caribbean: The Application of Principal Component Analysis

Cenotes are naturally occurring flooded caves that are frequent in Mexico's Yucatan Peninsula; they result from the collapse of limestone bedrock into the regional groundwater table. Cenotes in Quintana Roo are important ecological and economic hot spots but are susceptible to anthropogenic pollution. In this study, we collected water samples from 11 cenotes over multiple years to evaluate polycyclic aromatic hydrocarbon (PAH) concentrations and patterns as associated with tourist traffic. The primary PAHs detected in samples included fluoranthene, anthracene, phenanthrene and naphthalene, with total PAH concentrations increasing almost fivefold for cenotes sampled from 2016 to 2017. This is compared to only a 7% increase in tourist traffic during these years. Multivariate statistical analysis of the PAH concentration data suggests that diesel, gasoline and asphalt are the most likely pollution sources and that they are associated with periods of increased tourist traffic.

Baseline for plastic and hydrocarbon pollution of rivers, reefs, and sediment on beaches in Veracruz State, México, and a proposal for bioremediation

Plastic and hydrocarbon pollution in aquatic ecosystems is a worldwide reality and serious concern today. Plastic debris presents a threat to ecosystems and organisms. Hydrocarbons are also considered priority pollutants. The hydrophobicity of the polymer in combination with the high surface area causes plastics to act as a vector for organic contaminants such as hydrocarbons. The first aim of this work was to evaluate the presence of plastic and hydrocarbon pollution in water from two reefs and two rivers and to identify plastic in six sediment beaches in Veracruz State, Mexico. In addition, the second aim was to analyse the ability of a bacterial consortium to biodegrade hydrocarbons in an airlift bioreactor and to identify degrading bacterial strains of polyethylene terephthalate (PET). Microplastics (100 nm-5 mm) were found in four water samples. Fragments of plastic collected from the reefs ranged in size from 0.716 to 32 μm and in rivers from 0.833 to 784 μm. On the sediment beaches, macroplastics of sizes 2-10 cm were detected. A number of hydrocarbons were also detected in the water samples of both reefs and one river, including n-octane, n-nonane, phenanthrene, n-eicosane, n-dotriacontane, n-hexatriacontane, n-triacontane, and n-tetratriacontane. As a biotechnological alternative for remediation of hydrocarbons and plastics, we attempted to produce a collection of native microorganisms able to degrade them. This work shows results from the bioprospection of a bacterial consortium (Xanthomonas, Acinetobacter bouvetii, Shewanella, and Aquamicrobium lusatiense) for hydrocarbon biodegradation in an airlift bioreactor. The tested consortium was able to successfully degrade the maximum diesel concentration (20 g L^-1) tested for 10 days. Also, the first visual evidence of PET degradation by an isolated forest-native bacterial strain showed that Bacillus muralis is the most efficient degrader.

Bacillus spp. characterization and his intervention as a possible non-traditional etiology of chronic renal insufficiency in Tierra Blanca, Veracruz, Mexico

Environmental, socioeconomic, educational, custom, occupation, and native pathogen microbiota factors have been identified as unique etiological factors by region for chronic renal insufficiency (CRI). In the region of Tierra Blanca, Veracruz, there is a significant incidence of CRI. The objective of this research was to identify the presence of the genus Bacillus spp. and its kinetic characterization for recognition as a possible non-traditional etiology of CRI in the region. The methodology included the isolation and morphological, biochemical, molecular and kinetic characterization of strains of the genus Bacillus spp. and an analysis of factors that indicate that their presence could affect the occupational health of the population, prompting cases of CRI. The presence of Bacillus cereus (pathogenic strain for humans) was established (biochemical identification, similarity 99%, by 16S rRNA gene) in sugarcane crops, mainly in the MEX-69-290 variety, with the higher growth rate and lower lag phase, compared to the other isolates. The strains are reported as a potential danger of direct infection and a risk factor for the indirect development of CRI, in the non-traditional cause modality, in the sugarcane fields. It is recommended that committed actions be undertaken to protect and promote the health of the population.

Environmental Problems and the State of Compliance with the Right to a Healthy Environment in a Mining Region of México

The objective of this article is to review the environmental problems in Mexican state of San Luis Potosí (mining region) and the state of compliance with the right to a healthy environment. Our study helps to demonstrate complexity of the environmental impact in a broader context, if it is repeated in other mining regions of the non-developing world. The findings include heavy metals as lead and arsenic, in soil, with neurotoxic and carcinogenic properties. Impact on the biota as a whole, decrease of the biological activity and enzymatic inhibition. Heavy metals, including arsenic, mercury, cadmium and lead, as a product of the metallurgical and foundry industry were detected in children of the city of San Luis Potosí. Water contaminated with fluorine and arsenic, product of the extensive drilling of water wells and the transfer of contaminants from the mining and metallurgical industry. Air contaminated with heavy metals product of mining and metallurgy and hydrocarbons in urban and rural areas. Plastics as a global problem, but with the absence of local diagnosis, despite having one of the main pollution factors: industrial development. Hydrocarbons as pollution with very little diagnosis, beyond environmental emergencies. There is no evidence that the right to a healthy environment is fulfilled in the State of San Luis Potosí.

Diesel uptake by an indigenous microbial consortium isolated from sediments of the Southern Gulf of Mexico: Emulsion characterisation

In this study a microbial consortium, dominated by members of the genera Marinobacter and Alcanivorax (Gammaproteobacteria) isolated from marine sediments of Southern Gulf of Mexico, was assessed to grow in a bubble column bioreactor using 13 g L^-1 of diesel (aliphatic and aromatic hydrocarbons mix including nonane and hexadecane) as the sole carbon source. The consortium was able to produce 3.3 g L^-1 of biomass, measured as suspended solids. Microbial growth was detectable, even substrate depletion, after 8 days of cultivation. The emulsifier activity and its influence on the droplet size were also evaluated: it was observed that droplet diameter decreases as emulsifier activity increases. The bubble column bioreactor system proposed in this research could be used as a biotechnological process for the remediation of a contaminated body in important petrochemical regions, for example, Veracruz, México, where some points of sea and fresh-water bodies were analysed to find nonane and hexadecane in all sample water. It is important due to a lack of information, regarding hydrocarbon pollution in this port area, is filled.

Antioxidant Activity of Collagen Extracts Obtained from the Skin and Gills of Oreochromis sp

Efforts aimed at reduction of fishing waste generated during the evisceration and filleting are scarce. The fishing waste is used in the production of low value-added products, such as flours or silages. It is important to visualize an alternative and profitable use of this waste, as it constitutes a serious environmental problem. This research determined the antioxidant properties of collagenous extracts of skin and galls of Oreochromis sp. The raw materials were characterized by proximal chemical analysis. Three treatments were applied to extract the collagen: salt-soluble collagen, acid-soluble collagen (ASC), and pepsin-hydrolyzed collagen (PHC). The collagenous fractions were hydrolyzed (0.1% pepsin). The recovered collagen yield and antioxidant activity were determined to hydrolyzed collagen (HC) and nonhydrolyzed collagen (NHC). The ASC skin showed the highest extraction yield (3.02%). For galls, only the PHC extraction was feasible (0.16%). Antioxidant analysis of NHC did not reveal radical scavenging activities. HC displayed a 2,2-diphenyl-1-picrylhydrazyl %RSA of 22.58 (ASC skin) and 10.34% (PHC galls), and a 2,2'-azino-bis[3-ethylbenzothiazoline-6-sulfonic acid] %RSA of 30.40% (PHC skin) and 29.43% (PHC galls), respectively. The ASC skin and PHC gall extracts exhibited 94.40% and 81.54% in ferric-reducing antioxidant power, and 43.63 and 38.08 μg ascorbic acid equivalents per milli liter for total antioxidant capacity, respectively. The collagen extracts showed %RSA and chelation of pro-oxidant metal ions. Different mechanism of antioxidant action was identified for the extracts: radical scavengers for HC and metal ion chelators for NHC. In conclusion, red tilapia skin collagen is recommended as an active ingredient of nutraceuticals, pharmaceuticals, or functional foods, for the identified bioactive properties.

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.

Hydrocarbon water-pollution related to chronic kidney disease in Tierra Blanca, a perfect storm

Chronic kidney disease (CKD) affects the kidneys, and in severe cases is considered as end-stage renal disease which can only be treated by dialysis and transplantation. Tierra Blanca city has a higher CKD rate compared to other Mexican cities, but its principal cause has not been found yet. Main factors related to CKD are carbonated beverage consumption, diabetes, obesity, hypertension, heat stress, dehydration, and intoxication by pesticides, heavy metals, and/or hydrocarbons. The aim of this work was to evaluate hydrocarbon pollution in Tierra Blanca domestic fresh-water related to CKD and to integrate this information with other main factors in order to suggest precautionary actions taking account of key actors. We found hydrocarbons in the water wells of the city and the presence of other risk factors, which creates a perfect storm for CKD. Additionally, key actors were identified in order to follow precautionary principles related to CKD cases in Tierra Blanca.

Simultaneous Diesel and Oxygen Transfer Rate on the Production of an Oil-degrading Consortium in an Airlift Bioreactor: High-dispersed Phase Concentration

The aim of this study was to simultaneously evaluate diesel transfer rate (DTR) and oxygen transfer rate (OTR) on the production of an oil-degrading consortium in a three-phase airlift bioreactor (ALB) working at high hydrocarbon phase concentration with the purpose of determine whether the oxygen transfer rate is increased or diminished by an increase in the oil-phase concentration. Increase in hydrocarbon concentration allows an increase in DTR and a consequently higher DTR/OTR ratio thus avoiding hydrocarbon mass transfer limitations. This study demonstrates evidence that at high diesel concentrations, the main carbon fate is the production of biosurfactants.

Effect of Biomass Concentration on Oxygen Mass Transfer, Power Consumption, Interfacial Tension and Hydrodynamics in a Multiphase Partitioning Bioreactor

Several studies have reported that the hydrodynamics are not affected by the biomass in multiphase partitioning bioreactors. This work aims to demonstrate the effect of biomass concentration (0, 1, 3 and 5 g L−1) on the oxygen mass transfer coefficients, the droplet size of the dispersed phase, power consumption and superficial tension in a multiphase partitioning bioreactor (ionic liquid-aqueous-air-biomass system). At a biomass concentration of 5 g L−1, the oxygen mass transfer coefficient (kLa) increased by 55% (249 h−1) compared with the abiotic system (160 h−1). In the multiphasic system, the droplet size (d32) decreased when the biomass concentration was increased, producing an increment in the mass transfer area of the dispersed phase. In addition, the power consumption decreased by 44 % compared to a previous report without biomass. Furthermore, the increment of biomass concentration decreased the superficial tension by up to 15 %. A biomass increment in a multiphase system not also increases product yield, but also enhances the bioconversion process. The results obtained suggest that it is obligatory to consider the effect of biomass concentration on hydrodynamic characterisation, design, scale-up and optimisation for improving the performance of biotechnological processes using multiphase bioreactors.

Carcinogenic Hydrocarbon Pollution in Quintana Roo’s Sinkholes: Biotechnology for Remediation and Social Participation for Prevention

The State of Quintana Roo, in southeast of México, has important tourist attraction facilities, including underwater sinkholes popular among swimmers and divers. However, carcinogenic hydrocarbons were recently detected. The aim of this work was to demonstrate that biotechnology could represent an alternative to solve this problem; civil participation through the retrojection method could provide an alternative type of prevention.

Solid state fermentation (SSF): diversity of applications to valorize waste and biomass

Solid state fermentation is currently used in a range of applications including classical applications, such as enzyme or antibiotic production, recently developed products, such as bioactive compounds and organic acids, new trends regarding bioethanol and biodiesel as sources of alternative energy, and biosurfactant molecules with environmental purposes of valorising unexploited biomass. This work summarizes the diversity of applications of solid state fermentation to valorize biomass regarding alternative energy and environmental purposes. The success of applying solid state fermentation to a specific process is affected by the nature of specific microorganisms and substrates. An exhaustive number of microorganisms able to grow in a solid matrix are presented, including fungus such as Aspergillus or Penicillum for antibiotics, Rhizopus for bioactive compounds, Mortierella for biodiesel to bacteria, Bacillus for biosurfactant production, or yeast for bioethanol.

Dynamic Technique to Determine Hexadecane Transfer Rate from Organic Phase to Aqueous Phase in a Three-Phase Bioreactor

Determination of mass transfer of non-water soluble substrates, as hexadecane (HXD), is an important constraint in three-phase airlift bioreactor. A new simple dynamic technique able to measure the hexadecane transfer rate (HTR) in a three-phase airlift bioreactor (ALB) was studied in this work. The image analyses technique allowed measuring the resulting specific mass transfer area (aHXD). Gas chromatography was used to measure time-dependent transferred HXD and therefore the HXD transfer coefficient (kLHXD). Finally, HTR was calculated by using the equation HTR = kLaHXD•(CHXD* - CHXD) where CHXD* and CHXD are the saturation HXD-aqueous interphase and HXD aqueous phase concentration, respectively. As case study, we successfully applied to the measurement of HTR during a typical ALB microbial consortium culture; values from 0.010 to 0.042 mg HXD (L h)-1 were found. This technique could be used to compare similar simultaneously occurring parameters to assess mass transfer constraints in three-phase systems.