Publications by authors named "Guillermo C G Martinez-Avila"

Maize comes in a variety of colors, including white, yellow, red, blue, and purple, which is due to the presence of phytochemicals such as carotenoids, anthocyanins, flavonoids, phytosterols, and some hydroxycinnamic acid derivatives. In Mexico, maize is primarily grown for human consumption; however, maize residues comprise 51-58% of the total maize plant weight (stalks, leaves, ears, and husks) and are mainly used as livestock feed. These residues contain numerous bioactive compounds that interest the industry for their potential health benefits in preventing or treating degenerative diseases.

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Endophytic microbial communities colonize plants growing under various abiotic stress conditions. Candelilla (Euphorbia antisyphilitica Zucc.) is a shrub that develops functionally in arid and semi-arid zones of Mexico; these conditions generate an association between the plant and the microorganisms, contributing to the production of enzymes as a defense mechanism for resistance to abiotic stress.

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From a circular economy perspective, the appropriate management and valorization of winery wastes and by-products are crucial for sustainable development. Nowadays, grape pomace (GP) has attracted increasing interest within the food field due to its valuable content, comprising nutritional and bioactive compounds (e.g.

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Article Synopsis
  • - The study investigates how different extraction methods (Soxhlet, maceration, ultrasound-assisted) influence the phytochemical profile and antioxidant activity of guava leaf extracts, which are rich in polyphenolic compounds.
  • - The extraction yield of phenolic compounds ranged from 16 to 45 mg/g, with the Soxhlet method producing the strongest antioxidant effects based on various assays (ABTS, FRAP, Folin-Ciocalteu).
  • - Key bioactive compounds such as quercetin, kaempferol, and avicularin were identified, highlighting that both the method of extraction and purification significantly enhance the antioxidant capacity of guava leaf extracts.
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Microalgae have become promising microorganisms for generating high-value commercial products and removing pollutants in aquatic systems. This research evaluated the impact of sunlight intensity on intracellular pigment generation and phosphorus removal from secondary effluents by autoflocculating microalgae consortium BR-UANL-01 in photobioreactor culture. Microalgae were grown in a secondary effluent from a wastewater treatment plant, using a combination of low and high light conditions (photon irradiance; 44 μmol m s and ≈ 1270 μmol m s, respectively) and 16:8 h light:dark and 24:0 h light:dark (subdivided into 18:6 LED:sunlight) photoperiods.

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Oleogelation is an alternative process to improve the nutritional properties of food by creating soft-matter structures with the same functionality as commercial fats (shortenings). In this study, oleogels were produced by adding organic candelilla wax at 3% (OC03), 6% (OC06), and 9% (OC09) to extra-virgin linseed oil, and then characterized by their physicochemical properties. Furthermore, the physicochemical and sensorial properties of five cookie formulations were evaluated.

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The objective of the present work was to optimize the microencapsulation conditions of neem ( A. Juss) leaf extracts for the biocontrol of . The complex coacervation method was used for the encapsulation of the extracts.

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Cav. (Asteraceae), and endemic plant of Mexico is used in herbal medicine. In this study, the phytochemical composition, phenolic content, and antioxidant activity of ethanolic and methanolic extracts from leaves and flowers were determined.

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A comparative study was carried out on the chemical, structural and thermal properties of candelilla wax from four wax-producing communities in Mexico, which was obtained by two extraction processes, the conventional one using sulfuric acid (SA) and an eco-friendly alternative process using citric acid (CA) as the extracting agent. The waxes were analyzed by basic chemistry (acidity, saponification, ester indexes, and others), color, Fourier transform infrared spectroscopy (FTIR), Raman micro-spectroscopy, X-ray diffraction (XRD), differential scanning calorimetry (DSC), and hardness and brittleness measurements. The waxes obtained by the environmentally friendly process showed differences in their physicochemical properties when compared to waxes from the conventional process.

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Fungal secondary metabolites with antimicrobial properties are used for biological pest control. Their production is influenced by several factors as environment, host, and culture conditions. In the present work, the secondary metabolites from fermented extracts of Beauveria bassiana PQ2 were tested as antifungal agents against Gibberella moniliformis LIA.

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is a traditional crop and a rich source of bioactive compounds with various properties (e.g., antioxidant, anti-inflammatory, antifungal, UV defense, anti-glycemic, and cytotoxicity) that is primarily cultivated for essential oil recovery.

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In this work, polyphenols from Moringa oleifera (Mor) leaves were extracted by microwave-assisted extraction (MAE) and encapsulated by spray-drying (SD). Particularly, we explored the influence of tragacanth gum (TG), locust bean gum (LBG), and carboxymethyl-cellulose (CMC) as wall-materials on the physicochemical behavior of encapsulated Mor. Single or combined wall-material treatments (100:00 and 50:50 ratios, and total solid content 1%) were tested.

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In this study, an alternative extraction technique, ultrasound-assisted extraction, was used to extract the polyphenolic fraction from two different residues of the candelilla plant (). These metabolites were further analyzed to evaluate their bioactivity as antioxidants. In addition, their functional groups were identified by Fourier transform infrared (FTIR) spectroscopy.

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Zucc, better known as the candelilla plant, is one of the 10 non-timber forest products of greatest economic importance in the desert and semi-desert regions of Mexico. Moreover, it is a potential source of some functional phytochemicals such as polyphenolic compounds, wax and fiber, with potential applications in food, cosmetic and pharmaceutical industries. Thus, this review aims to describe these phytochemicals and their functional properties as antimicrobial, antioxidant, reinforcing and barrier agents.

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Aims: To use an agroindustrial waste (orange peels) as a source of polyphenols as a reducing medium for obtaining silver nanoparticles by greener method.

Background: Several techniques have been employed for AgNPs synthesis, nevertheless, most of them involve the use of toxic chemicals in the process. The use of fungi, bacteria, and plant extracts as subtracts for green synthesis is an ecofriendly alternative, although hypothetic, route for AgNPs large scale synthesis.

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The influence of ultrasound-assisted extraction of phytochemicals from Kunth on the antioxidant capacity was investigated. The factors evaluated were: ultrasound extraction time (10, 20 and 30 min), ethanol concentration (0, 35, 70 %) and solid/liquid ratio (1:4, 1:8 and 1:12 g mL). The L (3) array was applied, and the DPPH scavenging capacity of treatments was evaluated to obtain optimal extraction conditions.

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(avocado) is a fruit consumed worldwide; however, since avocado leaves are apparently a natural ingredient that can be used as a traditional medicine, they can be a potential source of bioactive compounds. This study aimed to analyze the antioxidant activity of seven Mexican avocado leaf extracts by DPPH, ABTS, and lipid peroxidation (LPO), and to identify the compound profile by liquid chromatography coupled to mass spectrometry/electron spray ionization. The highest free radical-scavenging activity was observed for Platano Delgado and Criollo 6 avocado cultivars havin IC values of 271.

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The total phenolic compounds content, free radical-scavenging capacity and capsaicinoid content in populations of wild Piquin chili () were studied. Aqueous and hydroalcoholic extracts from nine ecotypes were evaluated. High contents of phenolic compounds and free radical-scavenging capacities were observed for both extracts; however, the values that were found for the hydroalcoholic phase were substantially higher.

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In this work, impact of extraction methods (maceration, decoction, MAE, and UAE) on TPC, antioxidant activity, and the mass fraction of phenolics in several plant extracts (Punica granatum, Juglans regia, Moringa oleifera, and Cassia fistula) was investigated. The results showed that, despite the nature of matrix, the highest values of TPC in all samples were obtained by MAE as follows: PP (18.92±0.

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Objective: To evaluate differences in yield and composition of the essential oil and antioxidant contents in Turnera diffusa plants from localities in central region of Tamaulipas.

Methods: Samples were collected in Tamaulipas, Mexico in the arid zone. Essential oil was obtained through steam distillation and analyzed using GC-MS.

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Several plants that are rich in polyphenolic compounds and exhibit biological properties are grown in the desert region of Mexico under extreme climate conditions. These compounds have been recovered by classic methodologies in these plants using organic solvents. However, little information is available regarding the use of alternative extraction technologies, such as ultrasound.

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