Relative Water Content, Chlorophyll Index, and Photosynthetic Pigments on Lotus corniculatus L. in Response to Water Deficit.

This study aimed to evaluate different L. corniculatus L. ecotypes under water-deficit conditions to identify changes in relative water content and photosynthetic pigments as indicators of physiological responses during different years' seasons. The experiment was conducted in a randomized block design with three replicates. Ten treatments were performed as a factorial of 2 × 5, where the first variation factor was the soil water content-no water deficit (NDW) with 100% field capacity (FC), and water deficit (DW) corresponding to 85.4% of the FC-and the second variation factor comprised four ecotypes and one variety of L. corniculatus. A significant effect was identified on the concentration of photosynthetic pigments, mainly total chlorophyll, with chlorophyll a in the 255301 ecotype with records of 187.8, 167.5, and 194.6 mg g-1 FW in WD, corresponding to an increase of 86.0%, 172.6%, and 16.6%, respectively, in relation the lower values obtained in the ecotype 202700 under NWD. In carotenoids, higher concentrations were observed in the 255301 and 202700 ecotypes and the Estanzuela Ganador variety under WD in most seasonal periods, except summer; a similar response was found in the 202700 ecotype and the Estanzuela Ganador variety during the winter season, also in WD. The results showed that the first two principal components accounted for 71.8% of the total variation, with PC1 representing chlorophyll a, chlorophyll b, and total chlorophyll, and PC2 representing carotenoids, temperature, relative chlorophyll index, and relative water content. The observations were grouped based on soil moisture content, with the optimal moisture group exhibiting higher chlorophyll and carotenoid concentrations. The findings suggest that soil moisture content significantly affects the performance of L. corniculatus ecotypes, and the plant shows seasonal variations in response to water-deficit conditions. This research contributes to understanding the physiological responses of L. corniculatus and its potential as a water-efficient forage crop for promoting sustainable agriculture and enhancing food security.

Biological effects of aqueous extract from Turkey vulture Cathartes aura (Cathartidae) meat.

ETHNOPHARMACOLOGICAL RELEVANCE: Cathartes aura is a bird used in the Mexican traditional medicine for the empirical treatment of cancer, injuries, infections and burns. MATERIALS AND METHODS: The in vitro immunomodulatory effects of Cathartes aura extract (CAE) were evaluated estimating its effects on proliferation of human peripheral blood mononuclear cells and murine splenocytes. The effects of CAE (1-200 µg/ml) on NO production, pinocytosis and lysosomal enzyme activity were assayed in murine macrophages RAW 264.7. The cytotoxic effects of CAE (1-500 µg/ml) on tumorigenic and non tumorigenic cells were evaluated using the MTT assay. RESULTS: In the absence of LPS, CAE induced the proliferation of murine splenocytes (119%), enhanced the pinocytosis (113%) and lysosomal enzyme activity (141%) in murine macrophages with a similar potency than lypopolisaccharides 1 µg/ml. In addition, CAE exerted cytotoxic effects mainly on human cervical cancer cells (IC(50)=117 µg/ml) but lacked toxic effects on non tumorigenic cells (IC(50)>500 µg/ml). CONCLUSION: Cathartes aura exerts immunostimulatory and cytotoxic activities.

Antimicrobial activity and cytotoxic effects of Magnolia dealbata and its active compounds.

Multi-drug resistance is of great concern for public health worldwide and necessitates the search for new antimicrobials from sources such as plants. Several Magnolia (Magnoliaceae) species have been reported to exert antimicrobial effects on sensitive and multidrug-resistant microorganisms. However, the antimicrobial properties of Magnolia dealbata have not been experimentally evaluated. The antimicrobial effects of an ethanol extract of Magnolia dealbata seeds (MDE) and its active compounds honokiol (HK) and magnolol (MG) were tested against the phytopathogen Clavibacter michiganensis subsp. michiganensis and several human multi-drug resistant pathogens using the disk-diffusion assay. The effects of MDE and its active compounds on the viability of human peripheral blood mononuclear cells (PBMC) were evaluated using MTT assay. MDE and its active compounds had antimicrobial activity (inhibition zone > 10 mm) against C. michiganensis, Pseudomonas aeruginosa, Acinetobacter baumannii, Acinetobacter lwoffii, Candida albicans, Candida tropicalis and Trichosporon belgeii. The results suggest that M. dealbata and its active compounds have selective antimicrobial effects against drug-resistant fungal and Gram (-) bacteria and exert minimal toxic effects on human PMBC.

Antimicrobial and cytotoxic effects of Mexican medicinal plants.

The antimicrobial effects of the Mexican medicinal plants Guazuma ulmifolia, Justicia spicigera, Opuntia joconostle, O. leucotricha, Parkinsonia aculeata, Phoradendron longifolium, P. serotinum, Psittacanthus calyculatus, Tecoma stans and Teucrium cubense were tested against several human multi-drug resistant pathogens, including three Gram (+) and five Gram (-) bacterial species and three fungal species using the disk-diffusion assay. The cytotoxicity of plant extracts on human cancer cell lines and human normal non-cancerous cells was also evaluated using the MTT assay. Phoradendron longifolium, Teucrium cubense, Opuntia joconostle, Tecoma stans and Guazuma ulmifolia showed potent antimicrobial effects against at least one multidrug-resistant microorganism (inhibition zone > 15 mm). Only Justicia spicigera and Phoradendron serotinum extracts exerted active cytotoxic effects on human breast cancer cells (IC50 < or = 30 microg/mL). The results showed that Guazuma ulmifolia produced potent antimicrobial effects against Candida albicans and Acinetobacter lwoffii, whereas Justicia spicigera and Phoradendron serotinum exerted the highest toxic effects on MCF-7 and HeLa, respectively, which are human cancer cell lines. These three plant species may be important sources of antimicrobial and cytotoxic agents.