Laila Nayzzel Muñoz Castellanos

Heavy metal(loid) (HM) contamination in soils from smelting activities poses significant environmental and public health risks, as well as disruptions in microbial community dynamics and HM resistance gene profiles. This study investigates the microbial diversity, resistome, and physicochemical properties of soils from the abandoned Avalos smelter in Chihuahua, Mexico. Through soil analyses, we identified elevated concentrations of certain HMs, which pose serious environmental and health hazards. The metagenomic analysis of the microbial community, composed of bacteria, archaea, and fungi, was dominated by genera such as Streptomyces, Bradyrhizobium, Halobaculum, Nitrosocosmicus, Fusarium, and Aspergillus in rhizospheric soil. Furthermore, a diverse array of metal resistance genes (MRGs) were detected, associated with copper, arsenic, iron, lead, cadmium, zinc, and other HMs. Additionally, metagenome-assembled genomes (MAGs) revealed the presence of functional genes linked to HM resistance, providing deeper insights into the ecological roles and metabolic capabilities of microbial taxa. These findings highlight the significant impact of smelting-derived contamination on microbial diversity and functional potential, offering valuable insights for the development of bioremediation strategies in HM-contaminated environments.

Arthrospira platensis (Ap) and Bacillus coagulans (Bc) have been successfully used to develop functional foods, but a combination of both regarding functional implications in nutritional value and antioxidant capacity has not been explored. This work aimed to develop an artisanal wheat flour pasta with egg using 5% A. platensis and 1% B. coagulans GBI 6068 (labeled as Bc+Ap). Uncooked pasta was characterized regarding nutritional value; furthermore, total phenolic content, antioxidant capacity by 2,2′-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid (ABTS), and ferric reducing antioxidant power (FRAP), pigment content, colorimetry assay, textural profile analysis, buffering capacity, and probiotic viability were carried out on uncooked and cooked pasta to assess the changes induced by cooking. The Bc+Ap pasta showed enhanced nutritional value with a significant increase in protein content (30.61%). After cooking, the pasta showed increased phenolic content (14.22% mg GAE/g) and antioxidant capacity (55.59% µmol Trolox equivalents/g and 10.88% µmol Fe⁺²/g) for ABTS and FRAP, respectively, as well as pigment content (6.72 and 1.17 mg/100 g) for chlorophyll a+b and total carotenoids, respectively, but relative impacts on colorimetric parameters in contrast to control (wheat flour pasta). Furthermore, Bc+Ap showed improved firmness (59%, measured in g), buffer capacity (87.80% μmol H⁺(g × ΔpH)⁻¹), and good probiotic viability (7.2 ± 0.17 log CFU/g) after the cooking process.

Arthrospira platensis (Ap) and Bacillus coagulans (Bc) have been successfully used to develop functional foods, but not a combination of both regarding functional implications in nutritional value and antioxidant capacity. This work aimed to develop an artisanal wheat flour pasta with egg using 5% A. platensis and 1% B. coagulans GBI 6068 (Bc+Ap). Uncooked pasta was characterized regarding nutritional value; furthermore, total phenolic content, antioxidant capacity (by ABTS and FRAP), pigment content (chlorophyll a + b, and total carotenoids), colorimetry assay, textural profile analysis, buffering capacity and probiotic viability were carried out on uncooked and cooked pasta to assess the changes induced by cooking. The Bc+Ap pasta showed enhanced nutritional value with a significant increase in protein content (30.61%). After cooking, the pasta increased phenolic content (14.22% mg GAE/g), antioxidant capacity (55.59% µmol Trolox Equivalents/g and 10.88% µmol Fe+2/g) for ABTS and FRAP respectively, pigment content (6.72 and 1.17 mg/100g), for chlorophyll a+b and total carotenoids respectively, but relative positive impacts on colorimetric parameters in contrast to control (wheat flour pasta). Furthermore, Bc+Ap showed improved firmness (59%, measured in g), buffer capacity (87.80% μmol H+(g × ΔpH)−1), and good probiotic viability (7.2 ± 0.17 log CFU/g) after the cooking process.

The rhizospheric microorganisms of agricultural crops play a crucial role in plant growth and nutrient cycling. In this study, we isolated two Streptomyces strains, Streptomyces sp. LM32 and Streptomyces sp. LM65, from the rhizosphere of Vitis vinifera L. We then conducted genomic analysis by assembling, annotating, and inferring phylogenomic information from the whole genome sequences. Streptomyces sp. strain LM32 had a genome size of 8.1 Mb and a GC content of 72.14%, while Streptomyces sp. strain LM65 had a genome size of 7.3 Mb and a GC content of 71%. Through ANI results, as well as phylogenomic, pan-, and core-genome analysis, we found that strain LM32 was closely related to the species S. coelicoflavus, while strain LM65 was closely related to the species S. achromogenes subsp. achromogenes. We annotated the functional categories of genes encoded in both strains, which revealed genes involved in nitrogen and phosphorus metabolism. This suggests that these strains have the potential to enhance nutrient availability in the soil, promoting agricultural sustainability. Additionally, we identified gene clusters associated with nitrate and nitrite ammonification, nitrosative stress, allantoin utilization, ammonia assimilation, denitrifying reductase gene clusters, high-affinity phosphate transporter and control of PHO regulon, polyphosphate, and phosphate metabolism. These findings highlight the ecological roles of these strains in sustainable agriculture, particularly in grapevine and other agricultural crop systems.

The rhizosphere is a dynamic and highly interactive habitat where diverse microbial communities are established, and it plays crucial roles in plant health and disease dynamics. In this study, microbial communities and functional profiles in the rhizosphere of both asymptomatic and symptomatic apple trees were investigated through amplicon sequencing and shotgun metagenomics. The research was conducted at a location in the municipality of Cuauhtemoc, Chihuahua State, Mexico, and a total of 22 samples were collected, comprising 12 for amplicon sequencing and 10 for shotgun metagenomic sequencing. Symptomatic trees were identified based on reddish branches and internal necrosis in the trunk and root, while asymptomatic trees exhibited a healthy physiology. The findings showed that the dominant bacterial phyla included Proteobacteria, Actinobacteria, and Bacteroidetes, with prevalent genera such as Streptomyces, Pseudomonas, and Rhodanobacter. The fungal communities featured Ascomycota, Mortierellomycota, and Basidiomycota, which were dominated by Fusarium, Penicillium, and Mortierella. In the fungal communities, Mortierellomycota, notably abundant in asymptomatic trees, holds potential as a biocontrol agent, as seen in other studies on the suppression of Fusarium wilt disease. The application of shotgun metagenomic sequencing revealed significant differences in alpha and beta diversities in bacterial communities, suggesting a health-dependent change in species composition and abundance. Functional profile analysis highlighted enzymatic activities associated with lipid synthesis/degradation, amino acid biosynthesis, carbohydrate metabolism, and nucleotide synthesis, which have been documented to participate in symbiotic relationships between plants. These insights not only contribute to understanding the dynamics of rhizosphere microbial activity but also provide valuable perspectives on the potential application of microbial communities for tree health and implications for the management of apple orchards.

Rhizosphere microorganisms play an important role in the growth and health of plants. Around the world, diverse soil-borne pathogens attack Capsicum annuum causing significant damage and economic losses. This study determined whether the diversity and composition of microbial communities in the rhizosphere soil of C. annuum plants is significantly changed by wilt disease. We used the 16S rRNA gene for bacteria and the internal transcribed spacer region for fungi to characterize the rhizosphere microbiomes of healthy and wilted plants. The most abundant bacterial phyla were Proteobacteria and Gemmatimonadetes, while the most abundant fungal phyla were Ascomycota and Mucoromycota. The bacterial α-diversity did not show significant differences in richness and diversity, but did show a significant difference in evenness and dominance of species. Rare taxa were present in both healthy and wilted conditions with relative abundances < 1%. In the fungi, all evaluated estimators showed a significant reduction in the wilted condition. The β-diversity showed significant differences in the structure of bacterial and fungal communities, which were segregated according to plant health conditions. The same occurred when comparing the alpha and beta diversity of this study based on organic agriculture with that of other studies based on conventional agriculture. We observed a significant difference with estimators analyzed by segregating rhizosphere communities depending on the farming method used. Finally, the differential abundance analysis did not show significant results in the bacterial communities; however, in the fungal communities, Fusarium, Thanatephorus, Rhizopus, Curvularia, Cladosporium, and Alternaria were more abundant in the rhizosphere of wilted than healthy plants. Species from these genera have been previously reported as phytopathogens of several plants, including C. annuum.

Polyphenols, as secondary metabolites from plants, possess a natural antioxidant capacity and biological activities attributed to their chemical and structural characteristics. Due to their mostly polar character, polyphenols present a low solubility in less polar environments or hydrophobic matrices. However, in order to make polyphenols able to incorporate in oils and fats, a transformation strategy is necessary. For the above, the functionalization of polyphenols through chemical or enzymatic lipophilization has allowed the synthesis of phenolipids. These are amphipilic molecules that preserve the natural phenolic core to which an aliphatic motif is attached by esterification or transesterification reactions. The length of the aliphatic chain in phenolipids allows them to interact with different systems (such as emulsions, oily molecules, micelles and cellular membranes), which would favor their use in processed foods, as vehicles for drugs, antimicrobial agents, antioxidants in the cosmetic industry and even in the treatment of degenerative diseases related to oxidative stress

In recent years there has been a growing concern about environmental pollution linked to the generation of agroindustrial waste. The wine industry generates approximately 8.49 million tons of grape pomace per year worldwide; this residue can be used to obtain compounds with biological activity. Grape pomace is a source of anthocyanins, pigments that have antioxidant properties and help prevent cardiovascular disease. The development of sustainable extraction, purification and identification techniques constitutes an important step in adding value to this waste. Therefore, the present research has focused on presenting a review of works carried out in the last years.