The Role of Biopolymers in Obtaining Environmentally Friendly Materials

Polymeric materials have had a boom in the global industry over the past two decades, because of its adaptability, durability, and price so much so that now we cannot imagine a product that does not contain it. However, many synthetic polymers that have been developed are mainly derived from petroleum and coal as raw material, which make them incompatible with the environment, since they cannot be included in what is a natural recycling system. Aware of the environmental impacts that produce synthetic polymers, a solution could be the mixtures with different types and sources of biological materials, called biopolymers, such as starch, cellulose, chitosan, zein, gelatin among others and that gradually replace synthetic polymers to address and resolve these problems. The development of new applications, such as composite materials by incorporation of alternative materials, found in nature that has similar properties to oil‐based polymers, but its main feature is its biodegradability and offering competitive to current material costs. In this sense, various investigations are aimed at decreasing the amounts of plastic waste and to manufacture products with less aggressive environment since the synthetic plastics are difficult to recycle and can remain in nature for over a century

Heavy Metal Pollution as a Biodiversity Threat

Heavy metals exert their toxic effects through different mechanisms. Lately, increasing attention has been focused on understanding the long-term ecological effects of chronically exposed populations and communities and their consequences to the ecosystem. The long-term exposure to heavy metals in the environment represents a threat to wild populations, affecting communities and putting ecosystem integrity at risk. Therefore, this type of exposure represents a threat to biodiversity. In the field, metal exposure is generally characterized by low doses and chronic exposures. This type of exposure exerts alterations across levels of biological organization. Distribution and abundance of populations, the community structure and the ecosystem dynamics may be altered. This chapter will focus on how chronically metal exposures in the field affect negatively populations and communities becoming a threat to biodiversity. Also, attention is put on the tools that enable to characterize and analyze the detrimental effects of heavy metal exposure on wild populations. Hence, the use and development of biomarkers in ecotoxicology will be discussed

The Use of Biosensors for Biomonitoring Environmental Metal Pollution

The use of biosensors for biomonitoring environmental health has gained much attention in the last decades. The environment is continuously loaded with xenobiotics released by anthropogenic activities that pollute ecosystems, putting their integrity at risk. Therefore, there is an urgent need to study the negative effects of xenobiotics, specifically chemical agents. Biosensors or organisms that integrate exposure to pollutants in their environment and which respond in some measurable and predictable way are useful tools to study the extent of chemical pollution and its consequences across levels of biological organization. Among chemical pollutants, heavy metals are among the most toxic elements to nearly all living organisms. Wildlife is chronically exposed to complex metal mixtures in which effects on ecosystem health are difficult to assess. Therefore, different organisms may serve as biosensors to estimate detrimental effects of metal pollution. In this chapter, we will analyze bacteria, small mammals, some plant species, and lichens as biosensors for environmental metal pollution. Also, we will assess the importance of using different biomarkers on biosensors

Transcriptional analysis reveals the metabolic state of Burkholderia zhejiangensis CEIB S4-3 during methyl parathion degradation

Burkholderia zhejiangensis CEIB S4-3 has the ability to degrade methyl parathion (MP) and its main hydrolysis byproduct p-nitrophenol (PNP). According to genomic data, several genes related with metabolism of MP and PNP were identified in this strain. However, the metabolic state of the strain during the MP degradation has not been evaluated. In the present study, we analyzed gene expression changes during MP hydrolysis and PNP degradation through a transcriptomic approach. The transcriptional analysis revealed differential changes in the expression of genes involved in important cellular processes, such as energy production and conversion, transcription, amino acid transport and metabolism, translation, ribosomal structure and biogenesis, among others. Transcriptomic data also exhibited the overexpression of both PNP-catabolic gene clusters (pnpABA′E1E2FDC and pnpE1E2FDC) present in the strain. We found and validated by quantitative reverse transcription polymerase chain reaction the expression of the methyl parathion degrading gene, as well as the genes responsible for PNP degradation contained in two clusters. This proves the MP degradation pathway by the strain tested in this work. The exposure to PNP activates, in the first instance, the expression of the transcriptional regulators multiple antibiotic resistance regulator and Isocitrate Lyase Regulator (IclR), which are important in the regulation of genes from aromatic compound catabolism, as well as the expression of genes that encode transporters, permeases, efflux pumps, and porins related to the resistance to multidrugs and other xenobiotics. In the presence of the pesticide, 997 differentially expressed genes grouped in 104 metabolic pathways were observed. This report is the first to describe the transcriptomic analysis of a strain of B. zhejiangensis during the biodegradation of PNP

High variability of perezone content in rhizomes of Acourtia cordata wild plants, environmental factors related, and proteomic analysis

With the aim of exploring the source of the high variability observed in the production of perezone, in Acourtia cordata wild plants, we analyze the influence of soil parameters and phenotypic characteristics on its perezone content. Perezone is a sesquiterpene quinone responsible for several pharmacological effects and the A. cordata plants are the natural source of this metabolite. The chemistry of perezone has been widely studied, however, no studies exist related to its production under natural conditions, nor to its biosynthesis and the environmental factors that affect the yield of this compound in wild plants. We also used a proteomic approach to detect differentially expressed proteins in wild plant rhizomes and compare the profiles of high vs. low perezone-producing plants. Our results show that in perezone-producing rhizomes, the presence of high concentrations of this compound could result from a positive response to the effects of some edaphic factors, such as total phosphorus (Pt), total nitrogen (Nt), ammonium (NH4), and organic matter (O. M.), but could also be due to a negative response to the soil pH value. Additionally, we identified 616 differentially expressed proteins between high and low perezone producers. According to the functional annotation of this comparison, the upregulated proteins were grouped in valine biosynthesis, breakdown of leucine and isoleucine, and secondary metabolism such as terpenoid biosynthesis. Downregulated proteins were grouped in basal metabolism processes, such as pyruvate and purine metabolism and glycolysis/gluconeogenesis. Our results suggest that soil parameters can impact the content of perezone in wild plants. Furthermore, we used proteomic resources to obtain data on the pathways expressed when A. cordata plants produce high and low concentrations of perezone. These data may be useful to further explore the possible relationship between perezone production and abiotic or biotic factors and the molecular mechanisms related to high and low perezone production.This work was supported by the Programa de Mejoramiento del Profesorado PROMEP/103.5/13/6626 and Consejo Nacional de Ciencia y Tecnología CONACyT-Mexico for Ph.D. scholarship 392123/254165. The University of Alicante lab is a member of Proteored, PRB3 and is supported by grant PT17/0019, of the PE I+D+I 2013-2016, funded by ISCIII and ERDF. Roque Bru-Martínez received financial support from the University of Alicante (VIGROB-105)

Assessing the Environmental Quality Resulting from Damages to Human-Nature Interactions Caused by Population Increase: A Systems Thinking Approach

Multiple interactions between population increase-as driving force- and pressure factors can cause damage to human-nature interactions. In this paper, we aim to identify, understand, and assess those interactions that exert effects on environment quality. The assessments of multiple interactions will allow selecting management actions to reduce negative effects, such as the loss of vegetation cover, on the environment. However, multiple interactions hinder the understanding of such complex systems. The relevance of this study is related to the support of the systems thinking approach to achieve two objectives: (1) to build a conceptual framework that facilitates the construction of a network aimed at representing the multiple interactions; (2) to build a closed system for the sake of developing a sustainable environmental management system. Thus, the performance of the implemented management actions is assessed through the feedback loop of the closed system. The proposed conceptual framework and the closed system were applied to the state of Morelos, Mexico. We highlight the following results: the systems thinking approach facilitated the construction of a conceptual framework to build understandable causal network; a set of environmental pathways were derived from the causal network and then combined to define and assess a global environmental state. Environmental pathways are composed of relationships between population increase and pressure variables that exert effects on the environment quality; the feedback loop facilitated the performance analysis of implemented management actions related to natural protected areas. The current results suggest further research to apply this study to diverse systems where multiple interactions between drivers and pressure factors damage human-nature interactions, thus exerting effects on the environmental state

Chemical Constituents and Their Production in Mexican Oaks (Q. Rugosa, Q. Glabrescens and Q. Obtusata)

Mexico is considered one of the main regions of diversification of the genus Quercus (oaks). Oak species are one of the most important tree groups, particularly in temperate forests, due to its diversity and abundance. Some studies have shown that oak contains specialized metabolites with medicinal importance. In this work, the acetonic extract from leaves of three Mexican oaks (Quercus rugosa, Q. glabrescens, and Q. obtusata) was separated using thin-layer chromatography and column chromatography. Chemical identification of the major compounds was determined using high-performance liquid chromatography and nuclear magnetic resonance. Nineteen compounds were identified, three belonging to the terpenoid family (ursolic acid, β−amyrin, and β−sitosterol) and 16 from the phenolic family. Of the isolated compounds, seven are new reports for oak species (scopoletin, ursolic acid, β-amyrin, luteolin−7−O−glucoside, kaempferol−3−O−sophoroside, kaempferol−3−O−glucoside, and kaempferol−3−O−sambubioside). More compounds were identified in Q. rugosa followed by Q. glabrescens and then Q. obtusata. The characterization of specialized metabolites in oak species is relevant, from both phytocentric and anthropocentric perspectives

First record of Ulex europaeus (Fabaceae, Faboideae) in Mexico

Antecedentes y Objetivos: La especie Ulex europaeus (Fabaceae, Faboideae) ha sido catalogada como una de las 100 especies invasoras más dañinas a nivel mundial. Es originaria del oeste de Europa y noroeste de África y se ha naturalizado en toda Europa y el Medio Oriente. Su impacto ambiental y económico en América está documentado en Canadá, Chile, Colombia y los Estados Unidos de América. Se encuentra en diferentes altitudes y tipos de vegetación. Con este estudio se busca contribuir al conocimiento de la distribución de Ulex europaeus en el territorio mexicano, como una base para acciones inmediatas respecto a su control y erradicación. Métodos: Se colectó material botánico en el bosque templado de la comunidad de Tres Marías, municipio Huitzilac, en el estado de Morelos, México. Para la determinación taxonómica se utilizaron claves dicotómicas y descripciones botánicas. Se realizó una revisión exhaustiva de literatura especializada, se consultaron imágenes, se obtuvieron datos de herbarios virtuales del mundo y se visitaron, para su consulta, los herbarios MEXU y UAMIZ. Los recorridos de campo en el estado de Morelos se apoyaron con proyecciones de ArcGIS. El material colectado está depositado en la colección del herbario HUMO de la Universidad Autónoma del Estado de Morelos. Resultados clave: Los autores registran por primera vez mediante colectas botánicas la presencia de U. europaeus en México. Apoyándose en recorridos en campo y la revisión de varias fuentes de información, hasta el momento solo se ha encontrado una población de 63 individuos de esta especie. La fenología de la especie coincide con lo reportado para otras latitudes.  Conclusiones: Este registro amplía el rango de distribución de U. europaeus. La presencia de esta especie se suma a los factores reales y potenciales que están afectando a la biodiversidad de nuestro país. Es necesario establecer estrategias, acciones de control y eventual erradicación de esta especie invasora.Background and Aims: The species Ulex europaeus (Fabaceae, Faboideae) has been listed as one of the 100 most harmful invasive species worldwide. It is native to western Europe and northwestern Africa, and has become naturalized throughout Europe and the Middle East. Its environmental and economic impact in America is documented in Canada, Chile, Colombia and the United States of America. It is found at different altitudes and in vegetation types. This study aims to contribute to the knowledge of the distribution of Ulex europaeus in the Mexican territory, as a basis for immediate actions regarding its control and eradication. Methods: Botanical material was collected in the temperate forest of the community of Tres Marías, municipality Huitzilac, in the state of Morelos, Mexico. Dichotomous keys and botanical descriptions were used for taxonomic determination. An exhaustive review of specialized literature was carried out, images were consulted, and data were obtained from virtual herbaria around the world, and the herbaria MEXU and UAMIZ were visited for consultation. The field work in the state of Morelos was supported by ArcGIS projections. The collected material is deposited in the collection of the herbarium HUMO of the Autonomous University of the State of Morelos. Key results: The authors register for the first time, by means of botanical collections, the presence of U. europaeus in Mexico. Supported by field trips and the review of various sources of information, so far only a population of 63 individuals of this species has been found. The phenology of the species coincides with that reported for other latitudes Conclusions: This record broadens the distribution range of U. europaeus. The presence of this species adds to the real and potential factors that are affecting the biodiversity of our country. It is necessary to establish strategies, control actions and eventual eradication of this invasive species