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Poliomintha longiflora is a Mexican oregano, which has not been widely studied. This work aimed to describe the chemical composition, antimicrobial and antioxidant activities present in P. longiflora essential oil (EO), the hydrosol from EO extraction and extracts from waste solid residues (WSRs), identified as ethanol extract, ethyl acetate extract and the subfractions of ethanol and ethyl acetate extracts. The chemical characterization of the EO, hydrosol and WSR extracts was performed by GC–MS and HPLC. Their antioxidant activity was evaluated using two methods, and their antimicrobial activity was evaluated against Escherichia coli, Staphylococcus aureus, Listeria monocytogenes, Bacillus cereus, and Salmonella Typhimurium. Thirty-one chemical components were identified in the EO. The subfractions from the ethanol and ethyl acetate extracts contain methylmaleic anhydride, thymoquinone, thymol, carvacrol, thymol acetate, carvacrol acetate, and phenolic acids. The EO presented the highest biological activities for antioxidant (136.05 mg equivalent of ascorbic acid/g (AAE/g); IC50 83.70 μg/mL of 2, 2-diphenyl-1-picrylhydrazyl (DPPH)) and antimicrobial tests (minimal inhibitory concentration (MIC) value of 250–750 mg/L), while the hydrosol and the ethyl acetate extract from WSRs had the lowest antioxidant activity (14.16 and 12.29 mg AAE/g respectively), and the hydrosol had the lowest antimicrobial activity (MIC of 3000 mg/L). The data suggest that Mexican oregano P. longiflora hydrosol and extracts from waste solid residues can still have compounds with antimicrobial and antioxidant capacities.

The increase in the elderly population has generated concern to meet health demands. The research efforts to elucidate the mechanisms of damage associated with aging have also been significantly increased, especially in order to avoid the reduction of the cognitive abilities in geriatric patients, resulting from the damage generated mainly at the level of the hippocampus during old age. At present, many studies describe resveratrol as an antiaging component. There are reports that it can activate the Sirt1 gene related to antiaging, emulating the effects obtained by caloric restriction in rodents. The aim of the study was to evaluate the effect of chronic administration of resveratrol (10 mg/kg) on cognitive performance in behavioral tests after 8 months of treatment and on the preservation of cerebral integrity in the cytoarchitecture of regions CA1 and CA2. Results showed that the cytoarchitecture of the CA1 and CA2 regions in the hippocampus retained their integrity over time in rats treated with resveratrol, and the behavioral test performed revealed that chronic resveratrol administration for 8 months showed improvements in cognitive performance. The results indicate that resveratrol may exhibit therapeutic potential for age-related conditions.

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Biofilms are difficult to eliminate with standard antimicrobial treatments due to their high antibiotic resistance. Therefore, some plants contain natural compounds with antimicrobial activity that can control biofilm formation. The aim of this work was to evaluate the effect of Mexican oregano (Lippia berlandieri Schauer) essential oil (EO) on Pseudomonas aeruginosa and Salmonella Thyphimurium biofilm formation on stainless steel surfaces. EO was added to achieve final concentrations of 0, 200, 250, 300, 400, 600, 800, and 1,600 mg/L. Growth data were modeled using the modified Gompertz model. EO antimicrobial activity against biofilm can be observed for both microorganisms. Moreover, at an EO concentration below inhibition, there is a delay in biofilm formation, thus decreasing the number of microorganisms that are part of the biofilm. The maximum growth rate in biofilm formation showed an inversely proportional behavior in relation to EO concentration. P. aeruginosa requires nearly 1 h to start forming biofilms. There is a delay in biofilm formation, thus decreasing the number of microorganisms that are part of the biofilm (24 h for 400 mg/L and 18 h for 600 mg/L). Salmonella Thyphimurium biofilm formation is affected at 200 mg/L of Mexican oregano EO, causing film detachment from the stainless steel surface after 18 h, while at 250 mg/L biofilm formation was inhibited. Mexican oregano EO could inhibit the development of P. aeruginosa and Salmonella Thyphimurium biofilm formation on stainless steel surfaces. Salmonella was more susceptible than Pseudomonas to Mexican oregano EO according to the concentrations required to inhibit biofilm growth.

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Bean protein concentrate (BPC) as a protein source from seven varieties of Mexican common beans (alubia, flor de mayo, garbancillo, peruano, pinto, mantequilla, and negro) was utilized for formulating edible films (EF). EF were prepared with BPC (3% w/w) and glycerol as a plasticizer by the casting method; their thickness, water content, soluble matter, protein solubility, color, puncture strength, elongation, water vapor permeability (WVP), and chemical properties (Fourier transform infrared, FTIR, and spectroscopy) were evaluated. Tested EF had an average thickness of 0.045 ± 0.001 mm. Good stability was observed since the studied polymers did not exceed 35% of the total soluble matter while protein solubilities were not greater than 3%. EF made from peruano bean protein presented a lower value of total matter solubility (25.38 ± 2.24%) than the other tested EF. A low value of WVP (2.06 ± 0.25 × 10 −10 g m/Pa s m 2 ) was observed in films from negro bean protein, while EF from flor de mayo bean protein exhibited the highest values of puncture strength (17.35 ± 0.82 MPa) and elongation (38.21 ± 0.64%). Most bean protein EF had reddish or brownish color; however, films from alubia and peruano bean proteins displayed light yellowish colors. FTIR spectra of EF revealed that glycerol did not react with the studied bean proteins through covalent bonds.