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Two populations of Physalis patula Miller collected in different localities (Querétaro and Teotihuacán) of Central México were analyzed. Eight new compounds including three withanolides, physapatolides A-C (1-3), two labdanes, 12-epi-physacoztomatin (10) and physapatulone (12), besides three 12-O-glucosyl labdanes, patulosides A-C (13-15), were isolated from these collections. A series of known withanolides, flavonoids, labdanes, sucrose esters, and sterols were also isolated. Withanolides isolated of each population exhibited different substitution patterns of ring D, thus while 15,16-dioxygenated withanolides were found in the Querétaro population, oxygenation occurs at C-14 and C-15 in those isolated from Teotihuacán population. The structures of all the isolated compounds were determined by analysis of their spectroscopic and spectrometric data. The absolute configuration assigned to physapatolide A (1) was confirmed by X-ray diffraction analysis of its acetyl derivative 1a, while those of labdane diterpenoids were based on chemical correlations. The antibacterial activity of 16 of the isolated compounds (1-3, 5-9, 13, 14, and 16-21) and two derivatives (13a, 14a) was evaluated against five ATCC bacterial strains (Escherichia coli, Klebsiella pneumoniae, Pseudomonas aeruginosa, Staphylococcus aureus and Bacillus subtilis). Compounds 1-3 inhibited around 100 % the growth of S. aureus at 250 μg/mL (w/v). The minimum inhibitory concentrations (MIC) of compounds 1, 2, and 3, against S. aureus were 62.5, 125 and 62.5 μg/mL, respectively, whereas their MIC's against a Methicillin-resistant S. aureus (MRSA) clinical isolate were 125, 62.5 and 62.5 μg/mL, respectively., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024. Published by Elsevier B.V.)

Diseases caused by intestinal parasites such as protozoa represent a worldwide problem mainly for developing countries. From morbidity in different groups of people to cases of mortality in children and/or immunocompromised patients. In addition to the above, there is growing resistance to the drugs used in the treatment of these diseases, as well as undesirable side effects in patients. Therefore, there is an interest in the search for new alternatives for the base and/or development of new drugs with antiparasitic activities without harmful effects. In this sense, natural products offer to be a diverse source of compounds with biological activities. In this work, we describe the isolation and elucidation by 1D and 2D NMR spectroscopy of three cyclopeptides obtained from seeds of A. diversifolia Saff.: cherimolacyclopeptide D ( 1 ), squamin D ( 2 ), and squamin C ( 3 ). The fractions enriched in cyclopeptides, as well as a pure compound ( 1 ), showed antiprotozoal activity against E. hystolitica Schaudinn and Giardia lamblia Kunstler in vitro assays, with values of IC 50 = 3.49 and 5.39 μg mL -1 , respectively. The molecular docking study revealed that 1 has a strong interaction with targets used, including aldose reductase and PFOR enzymes. The antiprotozoal activity of cherimolacyclopeptide D is reported for the first time in this study.

Research Background: Authentic Mexican cheeses have potential health benefits, although there are few studies on their bioactive components. In this study, we analysed soluble extracts from añejo cheese from Zacazonapan (Mexico), obtained from two dairies (A and B) that used milk from cows of different breeds and differed in processing., Experimental Approach: The soluble extracts of Zacazonapan añejo cheese during ripening (0, 30, 95 and 180 days) were used to determine proximate composition, amino acid composition, peptide profile, molecular mass profile, antioxidant and antihypertensive activities., Results and Conclusions: The molecular mass of the released protein fragments ranged from 0.10 to 22.43 kDa. During ripening, amino acids such as Pro, His, Tyr, Trp, Met, Cys, Ala, Gly, Leu and Val were present, which are associated with antioxidant activity. The inhibition of β-carotene bleaching was below 50 % at all ripening times. A significant difference between the cheese samples was observed only after 180 days. Amino acids associated with angiotensin-I converting enzyme (ACE-I) inhibition were found in the extracts (Trp, Phe, Tyr, Pro, Lys and Arg). The highest activity was observed in cheese ripened for 180 days (IC 50 of cheese A and B was 0.38 and 0.42 mg/mL, respectively)., Novelty and Scientific Contribution: These results suggest that Zacazonapan añejo cheese is a potential source of antioxidant and antihypertensive peptides, which are influenced by the dairy factor (milk source and production technique) and ripening time. This is relevant as there are no reports of these bioactivities in this type of cheese., Competing Interests: CONFLICT OF INTEREST Authors declare no conflict of interest., (Authors.)

The oenological industry has benefited from the use of Nuclear Magnetic Resonance ( 1 H-NMR) spectroscopy in combination with Multivariate Statistical Analysis (MSA) as a foodomics tool for retrieving discriminant features related to geographical origins, grape varieties, and further quality controls. Said omics methods have gained such attention that Intergovernmental Organizations and Control Agencies are currently recommending their massive use amongst countries as quality compliances for tracking standard and degradation parameters, fermentation products, polyphenols, amino acids, geographical origins, appellations d'origine contrôlée and type of monovarietal strains in wines. This study presents, for the first time, a 1 H-NMR/MSA profiling of industrial Mexican wines, finding excellent statistical features to discriminate between oenological regions and grape varieties with supervised Orthogonal Projections to Latent Structures Discriminant Analysis (OPLS-DA). In a comparative way, it is applied with the 1 H-NMR/OPLS-DA workflow for the first time in ancestral and artisanal Mexican mezcals with promising results to discriminate between regions, agave species and manufacturing processes. The central aim of this comparative study is to extrapolate the know-how of wine-omics into the non-professionalized mezcal industry for establishing the NMR acquisition, preprocessing and statistical analysis basis to implement novel, non-invasive and highly reproducible regional, agave species and manufacturing-quality controls.

Present work comprises the use of different solid-state Nuclear Magnetic Resonance strategies for characterizing structural and motional aspects of the peptide matrix that compose a set of four lyophilized Mexican cheese aqueous soluble extracts, each with a controlled ripening. Heteronuclear dipolar coupling modulation schemes allowed to characterize local mobility and structural homogeneity of cheeses' peptide segments in the solid-state as a function of ripening. Results suggest that ripened samples with certain local flexibility but important structural homogeneity present efficient microbial inhibition against tested bacterial strains, whilst high local rigidity of peptides within ripened cheese soluble fractions could partially explain the observed lack of antimicrobial activity. The present study attempts to propose novel observables for lyophilized cheese water soluble extracts that could be partially associated to their ripening-dependent antimicrobial activities, whereas said observables shall contribute to the better targeting, design and optimization of solid-state natural food bio-preservatives., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2020 Elsevier Ltd. All rights reserved.)

(‒)-Encecanescin (1) has been isolated from the leaves of Eupatorium aschembornianum. Two conformers are present in the crystal structure as a result of molecular disorder. The structure of 1 was established by 1H- and 13C-NMR spectroscopy in CDCl3 solution using 2D NMR techniques (gHSQC, gHMBC and NOESY). A Monte Carlo random search using molecular mechanics followed by the geometry optimization of each minimum energy structure using density functional theory (DFT) calculations at the B3LYP/6-31G* level and a Boltzmann analysis of the total energies generated accurate molecular models describing the conformational behavior of 1. The three most stable conformers 2-4 of compound 1 were reoptimized at the B3LYP/6-311++G(d,p) level of theory using CHCl3 as a solvent. Correlations between the experimental 1H- and 13C-NMR chemical shifts (δexp) have been found, and the GIAO/B3LYP/6-311++G(d,p) calculated magnetic isotropic shielding tensors (σcalc) for conformers 2 and 3, δexp=a+b σcalc, are reported. A good linear relationship between the experimental and calculated NMR data has been obtained for protons and carbon atoms.