Lignocellulosic Membranes Grafted with N-Vinylcaprolactam Using Radiation Chemistry: Load and Release Capacity of Vancomycin.

Radiation chemistry presents a unique avenue for developing innovative polymeric materials with desirable properties, eliminating the need for chemical initiators, which can be potentially detrimental, especially in sensitive sectors like medicine. In this investigation, we employed a radiation-induced graft polymerization process with N-vinylcaprolactam (NVCL) to modify lignocellulosic membranes derived from Agave salmiana, commonly known as maguey. The membranes underwent thorough characterization employing diverse techniques, including contact angle measurement, degree of swelling, scanning electron microscopy (SEM), atomic force microscopy (AFM), Fourier-transform infrared-attenuated total reflectance spectroscopy (FTIR-ATR), nuclear magnetic resonance (CP-MAS 13C-NMR), X-ray photoelectron spectroscopy (XPS), and uniaxial tensile mechanical tests. The membranes' ability to load and release an antimicrobial glycopeptide drug was assessed, revealing significant enhancements in both drug loading and sustained release. The grafting of PNVCL contributed to prolonged sustained release by decreasing the drug release rate at temperatures above the LCST. The release profiles were analyzed using the Higuchi, Peppas-Sahlin, and Korsmeyer-Peppas models, suggesting a Fickian transport mechanism as indicated by the Korsmeyer-Peppas model.

Development of a Portland Cement-Based Material with Agave salmiana Leaves Bioaggregate.

Depending on the morphology of the natural fibers, they can be used as reinforcement to improve flexural strength in cement-based composites or as aggregates to improve thermal conductivity properties. In this last aspect, hemp, coconut, flax, sunflower, and corn fibers have been used extensively, and further study is expected into different bioaggregates that allow diversifying of the raw materials. The objective of the research was to develop plant-based concretes with a matrix based on Portland cement and an aggregate of Agave salmiana (AS) leaves, obtained from the residues of the tequila industry that have no current purpose, as a total replacement for the calcareous aggregates commonly used in the manufacturing of mortars and whose extraction is associated with high levels of pollution, to improve their thermal properties and reduce the energy demand for air conditioning in homes. Characterization tests were carried out on the raw materials and the vegetal aggregate was processed to improve its compatibility with the cement paste through four different treatments: (a) freezing (T/C), (b) hornification (T/H), (c) sodium hydroxide (T/NaOH), and (d) solid paraffin (T/P). The effect of the treatments on the physical properties of the resulting composite was evaluated by studying the vegetal concrete under thermal conductivity, bulk density, and compressive strength tests with a volumetric ratio between the vegetal aggregate and the cement paste of 0.36 and a water/cement ratio of 0.35. The hornification treatment showed a 15.2% decrease in the water absorption capacity of the aggregate, resulting in a composite with a thermal conductivity of 0.49 W/mK and a compressive strength of 8.66 MPa, which allows its utilization as a construction material to produce prefabricated blocks.

Influence of Prebiotic Activity of Agave salmiana Fructans on Mucus Production and Morphology Changes in Colonic Epithelium Cell of Healthy Wistar Rats.

The beneficial health of evaluating prebiotic effect by the consumption of Agave salmiana fructans (A. salmiana fructans) was assessed in the epithelium of the cecum and proximal colon of Wistar rats fed at different doses for 35 days with regards to mucus production, morphological cell changes, and the serum concentration of tumor necrosis factor-α (TNF-α). Results showed a significant increase in mucus-secreting cells (P < 0.05) and a normal structure with preserved crypts, without morphological damage to colonic cells for a dose of 12.5% (w/w) with respect to the control and the other doses evaluated. The concentration of pro-inflammatory cytokine TNF-α was decreased significantly (P < 0.05) in the groups with doses of 10 and 12.5% (w/w) at 7 and 35 days, respectively. This effect was positively correlated with the reduction of inflammation in epithelial cells. This study provides direct evidence of the effects of the A. salmiana fructans on the colonic epithelium, demonstrating that a diet supplemented with 12.5% of fructans for 35 days exerts health benefits through the strengthening of the mucosa layer, which favors the adherence of the bacterial population and suppresses inflammation.

Effect of Ohmic Heating on Sensory, Physicochemical, and Microbiological Properties of "Aguamiel" of Agave salmiana.

The use of ohmic heating (OH) processing technologies in beverages might provide a higher quality value to the final product; consumers tended to prefer more natural products with minimum preservative substances. The aim of this work was to evaluate the effect of OH over the presence of microorganisms in "aguamiel" as well as to study the effects on physicochemical analysis like total sugars, soluble solids, electric conductivity pH, and color. The results showed that the conductivity of "aguamiel" was 0.374 s/m, this as temperature increased, conductivity rose as well. During OH a bubbling was observed when reaching 70 °C due to the generation of electrochemical reactions during the OH process. OH had a significant effect in the reduction of E. coli, yeast, and lactobacillus compared to conventional pasteurization, reaching optimal conditions for its total inactivation. Regarding its physicochemical properties, both treatments, conventional pasteurization and OH, did not show negative changes in aguamiel, demonstrating that OH technology can be a feasible option as a pasteurization technique. In conclusion it is important to notice that negative changes were not found in quality, color and sugars of "aguamiel". Therefore, ohmic heating can be an option to replace traditional methods used for pasteurization.

Morphological Diversity and Genetic Relationships in Pulque Production Agaves in Tlaxcala, Mexico, by Means of Unsupervised Learning and Gene Sequencing Analysis.

Pulque is one of the oldest fermented beverages, with its origins dating back to pre-Hispanic Mexico. Recently, public consumption has increased. However, the majority of Agave plantations for pulque production have disappeared or been abandoned in recent decades. To create strategies for the conservation and production of pulque agaves, it is necessary to first determine their taxonomic identities and to better understand their genetic and morphological diversity. Despite the historical importance of pulque in Mexico, little attention has been placed on the study of Agave plants used for its production. Therefore, we analyzed the morphological diversity of vegetative characters of nine landraces of two Agave species (A. salmiana and A. mapisaga) which are widely cultivated for pulque production in Tlaxcala, Mexico. The analysis of morphological characters showed that the landraces largely clustered based on classic taxonomic relationships. One cluster of landraces associated with Agave mapisaga var. mapisaga and another with A. salmiana subsp. salmiana, but with the exception of A. salmiana subsp. salmiana "Ayoteco", which is more closely related with A. mapisaga var. mapisaga. Additionally, we analyzed the genetic relationships between 14 landraces and wild individuals using molecular markers (trnL and ITS). The identified genetic variants or haplotypes and genetic pools mainly corresponded with the species. In the case of "Ayoteco", incongruence between markers was observed. Low selection intensity, genetic flow events, and the plasticity of morphological traits may explain the high number of landraces without clear differences in their morphological diversity (vegetative characters) or genetic pools. The use of reproductive traits and massive sequencing might be useful for identifying possible morphological and genetic changes in the Agave landraces used for pulque production.

Nutritional Composition, Bioactive Compounds and Antioxidant Activity of Wild Edible Flowers Consumed in Semiarid Regions of Mexico.

In semiarid regions of Mexico, it is common to use the floristic richness of wild plants as food ingredients. Hence, flowers of Agave salmiana, Aloe vera, Erythrina americana, and Myrtillocactus geometrizans, which are typical and traditionally consumed flowers, were analyzed. The physicochemical properties; proximate composition; the contents of minerals, carotenoids, ascorbic acid, phenols, and total flavonoids; the quantification of phenolic compounds by HPLC; and the antioxidant activity in vitro were determined. The flowers were high in carbohydrates, proteins and minerals, mainly K and N in flowers from E. americana and M. geometrizans, respectively. The highest concentration of carotenoids was detected in red flowers (E. americana). Total phenols ranged from 4.73 to 72.40 mg of gallic acid equivalents per gram of dry weight (GAE/g DW). However, the highest value of antioxidant activity was 819.80 µmol of Trolox equivalents per gram of dry weight (TE/g DW). The highest values of phenolic compounds content and antioxidant activity were found in the flowers of M. geometrizans. The antioxidant activity of flowers was mainly related to phenolic compounds. The main phenolic compounds detected in flowers were rutin and phloridzin. The edible flowers analyzed in this study are a potential source of compounds with high biological activity.

Impact of Leuconostoc SD23 intake in obese pregnant rats: benefits for maternal metabolism.

Maternal obesity (MO) during pregnancy and lactation leads to maternal and offspring metabolic dysfunction. Recent research has suggested that probiotics might be a novel approach to counteract these unwanted MO effects. The aim of this research was to analyze the impact of Leuconostoc SD23, a probiotic isolated from aguamiel (traditional Mexican drink), on MO metabolism in rats at the end of lactation (21 days). From weaning through lactation, control female Wistar rats (C) ate chow (5% fat) or high-energy obesogenic diet (MO; 25% fat). Half the C and MO mothers received a daily dose (1 × 1010 CFU/ml) of probiotic orally, control with probiotic (CP) and MO with probiotic (MOP), 1 month before mating and through pregnancy and lactation. Histological analyses of the liver, white adipose tissue and small intestine, body composition, glucose, insulin, triglycerides, and leptin were determined in mothers at the end of lactation. Maternal weight during pregnancy was greater in MO than C mothers, but similar at the end of lactation. Probiotic intervention had no effect on maternal weight. However, at the end of lactation, percentage of body fat was higher in MO than C, CP, and MOP. Serum glucose, homeostasis model assessment of insulin resistance, and triglycerides were higher in MO versus C, CP, and MOP. MO small intestine villus height was higher versus MOP, C, and CP. Leuconostoc SD23 did not present adverse effects in C. Conclusions: maternal administration of Leuconostoc SD23 has beneficial effects on maternal metabolism, which holds possibilities for preventing adverse offspring metabolic programming.

Leuconostoc mesenteroides subsp. mesenteroides SD23 Prevents Metabolic Dysfunction Associated with High-Fat Diet-Induced Obesity in Male Mice.

High-fat diet (HFD) consumption induces obesity and increases blood glucose, insulin resistance, and metabolic disorders. Recent studies suggest that probiotics might be a novel approach to counteract these effects in the treatment of obesity. Here, we evaluated the effect of Leuconostoc mesenteroides subsp. mesenteroides SD23 on obesity-related metabolic dysfunction. In the present study, mice were randomly divided into four dietary groups: standard diet (C), HFD (OB), standard diet with L. mesenteroides SD23 (CP), and HFD with L. mesenteroides SD23 (OBP). Diets were maintained for 14 weeks. Animal weight was monitored and biochemical and histological analyses were performed after intervention. OB showed metabolic dysfunction, and increased the number of larger adipocytes compared to C. OB induced liver tumor necrosis factor-α (TNF-α) expression, increased cholesterol, leptin, and glucose levels compared to C. OBP reduced body weight, glucose, cholesterol, and leptin levels and improved glucose tolerance compared to OB. OBP also reduced liver steatosis, the number of larger adipocytes in adipose tissue, and reduced the villus height in the small intestine. OBP decreased expression of TNF-α and increased expression of IL-10 in liver. The parameters evaluated in the CP were similar to the C. This study provides novel evidence that dietary intervention with L. mesenteroides SD23 improves metabolic dysfunction related to obesity in HFD-fed mice.

Agave salmiana fructans as gut health promoters: Prebiotic activity and inflammatory response in Wistar healthy rats.

Prebiotic effects of Agave salmiana fructans at five different doses were evaluated by the growth of Bifidobacterium, Lactobacillus, and Clostridium strains and SCFA production in the cecum and proximal colon of healthy Wistar rats. Mucosal integrity, bacterial proliferation, and inflammatory response were also examined. Growth of Bifidobacterium and Lactobacillus strains was improved by 12.5% doses of fructans in both cecum and proximal colon tissues, and a significant decrease of Clostridium (P < 0.05) was observed. Increases in mucosal thickness, proliferation, and cell adhesion were mainly observed in the cecum. High concentration of butyric acid and total SCFA were contained in the 12.5% doses. This study provides direct evidence of the prebiotic effects of Agave salmiana fructans, demonstrating that a diet supplemented with a 12.5% dose of fructans promotes major growth of probiotic bacteria and could be used as a potential prebiotic ingredient under the conditions used in this study. Taken together, these results further indicate the significance of Agave salmiana fructans as a prebiotic ingredient in the regulation and prevention of gastrointestinal diseases, as well as for the design of functional foods.

Steroidal Saponin and Flavonol Content and Antioxidant Activity during Sporophyte Development of Maguey (Agave salmiana).

Agave salmiana Otto ex Salm-Dyck has traditionally been used for the production of fermented beverage known as "pulque" that has recently gained acceptance as a functional food. However, the plant requires up to 10 years to be used as raw material. The objective of this work was to evaluate the antioxidant and bioactive principles of Agave salmiana during different stages of development. Wild grown plants from Coahuila, Mexico, were identified based on leaf and spine traits to obtain a representative sample from six different stages of development (I-VI) from 1 to 7 years old. Total phenolic content (TPC), antioxidant activity (AOX), as well as composition and content of flavonols and saponins by HPLC-MS-TOF and HPLC-ELSD-PDA were evaluated. Concentrations of TPC were found to be between 5 to 13 mg gallic acid equivalents/g, reaching a maximum at stage II. The AOX presented a negative tendency from stage I to stage VI (from 148 to 50 µmol Trolox equivalents/g respectively). Kaempferol, quercetin and five saponins were identified. Similar to AOX, flavonols presented a negative concentration tendency with a reduction of 65% between the stage I and VI. Plants of stage III and IV presented the highest content of saponins, particularly chlorogenin glycoside, containing 3.19 and 2.90 mg protodioscin equivalents/g, respectively. These data suggest that plants from stages I to IV may be used as a source of antioxidant and bioactive principles, and that the content of these metabolites could be used as a marker to determine the developmental stage of the plant.

Effect of in vitro drought stress on phenolic acids, flavonols, saponins, and antioxidant activity in Agave salmiana.

This work evaluated the effect of in vitro drought stress on morphological characteristics, phenolic compounds, flavonols, saponin content, and antioxidant activity in plantlets of Agave salmiana. Drought stress was induced with polyethylene glycol (PEG) at 0, 10, 20 and 30% w/v in Murashige and Skoog solid medium. The determination of specific flavonols and saponins was achieved via HPLC-DAD and HPLC-ELSD, respectively. Compared with the control, plants grown in 30% PEG showed a change in the width of the leaves and a different color, showing less clarity and more darkening (L = 21.18, b = 14.27) and also had the lowest flavonol content, but the highest total saponin content (tigogenin glycoside, 163 mg of protodioscin equivalents/g dw) and the highest antioxidant activity. Total phenolic compounds did not significantly differ between treatments. Agave salmiana plants cultured in vitro increased their saponin content and antioxidant activity in response to drought stress induced via PEG.

Micropropagation of Agave salmiana: Means to Production of Antioxidant and Bioactive Principles.

Maguey, Agave salmiana, is an important plant for the "pulque" beverage and functional food industries; however, it has several constraints for elite and homogeneous plant production. In this study, a micropropagation process was established to generate in vitro plants. The effect of the method on metabolite content and antioxidant (AOX) activity in regenerated plants was evaluated. Young germinated plantlets were micropropagated from axillary shoots using Murashige and Skoog medium supplemented with L2 vitamins, 0.04 mg/L 2,4-dichlorophenoxyacetic acid and 10 mg/L 6-benzylaminopurine. Total soluble sugars from the aqueous fraction and total phenolic acids, total saponins, and AOX activity of the methanol fraction were determined in wild-type (WT) plants, in in vitro (IN) plants, and ex vitro acclimated plants (EN). The results showed that IN plants have a 50% lower soluble sugar content compared to WT, and EN. The total phenolic acids content was at least 30% higher in micropropagated (IN) and regenerated (EN) plants compared to WT. The total saponin content in IN, and EN plants was 36 and 25 times higher compared to WT. The AOX capacity of IN plants was on average three times higher compared to other treatments. However, no correlation was found between the AOX activity and total phenolic acids or total saponins. A negative and significant correlation (r = -0.927; p = 0.003) was found between the AOX activity and the total soluble sugars content. Micropropagated plants of A. salmiana have a different phytochemical content and bioactivity after the in vitro process compared to WT plants. The micropropagation process could be used as a platform for phytochemical enhancement of Agave plants.