María Crystal Columba-Palomares

Antimicrobial resistance has intensified the search for novel antimicrobial and wound-healing agents. Ludwigia octovalvis (Jacq.) P.H. Raven is traditionally used to treat infections, inflammation, and skin disorders, although its in vitro biotechnological potential remains largely unexplored. This study reports the first successful establishment of L. octovalvis callus cultures, their characterization by gas chromatography-mass spectrometry (GC-MS), and the evaluation of their antimicrobial and wound-healing activities. Friable calluses were induced from leaf and node explants of axenic seedlings using combinations of 6-benzylaminopurine (BAP), kinetin (KIN), 2,4-dichlorophenoxyacetic acid (2,4-D), and α-naphthaleneacetic acid (NAA). Optimal callus induction was achieved in leaf explants cultured on full-strength Murashige and Skoog (MS) medium supplemented with BAP (4.44 µM) and 2,4-D (0.45 µM). After six months of subculture, the calluses showed morphological uniformity and stable biomass production. Growth kinetics followed a specific growth rate of 0.047 d⁻¹ and a doubling time of 14.54 days. GC-MS analysis identified fatty acids and phytosterols as the main components. The ethyl acetate extract significantly improved wound healing in vivo, while the methanolic extract exhibited antibacterial activity against Staphylococcus aureus and methicillin-resistant S. aureus (MRSA). These findings demonstrate that L. octovalvis callus cultures constitute a sustainable source of bioactive compounds with promising therapeutic potential.

1. Parmentiera aculeata (Kunth) Seem., commonly known as cuajilote, belongs to the Bignoniaceae family and is part of the native vegetation of Mexico. (Alvarez-Olivera et al., 2010) In traditional ...

Due to Ludwigia octovalvis’ aquatic habitat’s vulnerability to climate change, this study developed an in vitro regeneration system using indirect organogenesis to ensure sustainable production of biomass and secondary metabolites. Treatment T16 (0.1 mg/L BAP and 1.0 mg/L NAA) was identified as the optimal hormonal regimen for callus induction and shoot differentiation. Phytochemical analysis by GC-MS revealed that seedlings regenerated under treatment T16 exhibited a diverse profile of 18 phytoconstituents, enhancing the accumulation of phytosterols, terpenes, and tocopherols. In vitro biological evaluation demonstrated that T16 extract possesses significant antibacterial activity (MIC < 62.5 µg/mL) against methicillin-resistant Staphylococcus aureus, and moderate antioxidant capacity. T16 extract showed anti-inflammatory effects superior to indomethacin at a low quantity (0.5 mg/ear) in adult CD1 mice of both sexes. In conclusion, the indirect organogenesis of L. octovalvis not only conserves the species but also optimizes its pharmacological potential, consolidating it as an efficient biotechnological platform for the development of advanced phytopharmaceuticals.

Background/Objectives: Bursera bipinnata (DC.) Engl. resin (locally known as “copal blanco”) is traditionally used in Mexican ethnomedicine to treat infected wounds and skin inflammation, but the bioactive constituents underlying these effects remain largely uncharacterized. This study aimed to identify the compounds responsible for the wound-healing properties of the resin through bioactivity-guided fractionation and to evaluate their anti-inflammatory and antibacterial activities as complementary mechanisms supporting tissue repair. Methods: Crude resin (1.2–5.0 mg/mL) was assayed for anti-inflammatory activity in the TPA-induced ear-edema model in BALB/c mice, for antibacterial activity (MIC) against six clinically relevant strains, and for wound-healing activity in a murine excisional model with pirfenidone (PFD) as the reference drug (n = 5 per group). Bioactivity-guided fractionation followed by spectroscopic elucidation (¹H- and ¹³C-NMR, IR, EI-MS) led to the isolation of five constituents. Stigmasterol, the most active compound, was subsequently evaluated in an LPS-induced systemic inflammation model (oral administration, 20 mg/kg/day × 3 days) to characterize its immunomodulatory profile (TNF-α, IL-1β, IL-6, IFN-γ, IL-10) and in the wound-healing model to quantify local IL-6, IL-10 and TGF-β1 in skin homogenates. Results: The crude resin (5.0 mg/mL) achieved 99.63% wound closure at day 12 and a 49.08% reduction in TPA-induced ear edema, comparable to indomethacin (55.76%). The resin displayed selective antibacterial activity against Streptococcus pyogenes (MIC 125 µg/mL) and Salmonella typhimurium (MIC 250 µg/mL). Bioactivity-guided fractionation yielded the phytosterol stigmasterol (1), three lupane-type triterpenoids (lupeol acetate (2), lupenone (3), 3-epilupeol (5)), and the sesquiterpenoid caryophyllene oxide (4). At an equimolar 1 µM concentration, stigmasterol (1) shortened the mean wound-healing time to 10.3 ± 0.4 days, comparable to pirfenidone, and was associated with attenuation of systemic TNF-α, IL-1β and IL-6 peaks and with sustained local IL-10 and TGF-β1 expression. Histological assessment confirmed accelerated re-epithelialization and improved collagen organization. The resin was non-irritant in the OECD 404 acute dermal test (Primary Irritation Index = 0.00). Conclusions: These findings provide pharmacological evidence supporting the traditional use of B. bipinnata resin for wound healing. Stigmasterol (1), together with the lupane-type triterpenoids lupenone (3) and 3-epilupeol (5), were identified as key bioactive constituents. The data are consistent with a coordinated immunomodulation, in which stigmasterol is associated with reduced systemic pro-inflammatory signalling and increased local IL-10/TGF-β1 expression, an interpretation that should be confirmed in chronic and impaired wound-healing models.

Acmella radicans, commonly known as the “toothache plant,” is traditionally attributed with medicinal properties, although few studies have validated its biological effects. In the present study, a chemical analysis of the wild plant was performed using gas chromatography–mass spectrometry (GC-MS). In addition, the antioxidant, anti-inflammatory, and antibacterial potential of ethanolic extracts from the roots (RE) and aerial parts (AE), as well as their respective fractions, was evaluated. The dichloromethane fractions of the aerial parts (DFAE) and root extracts (DFRE) at a concentration of 25 μg/mL demonstrated the highest inhibition of nitric oxide (NO) production, reducing levels to 22.2 ± 1.9 and 22.2 ± 2.9 μM, respectively. Moreover, these fractions exhibited a notable inhibition of TNF-α production, lowering its concentration to 22.6 ± 3.3 pg/mL (DFAE) and 24.8 ± 5.3 pg/mL (DFRE) at 25 µg/mL. GC-MS chemical profiling revealed the presence of alkamides such as N-isobutyl-2E,6Z,8E-decatrienamide, N-(2-methylbutyl)-2E,6Z,8E-decatrienamide, and N-(2-phenylethyl)-2E,4Z-octadienamide in both root and aerial part extracts. The dichloromethane fractions showed a higher abundance of alkamides compared to the hexane fractions, suggesting that these compounds may be at least partially responsible for the observed anti-inflammatory activity. Additionally, AE showed moderate activity against S. typhimurium and low activity against other bacteria, while RE was especially effective against a resistant strain of S. aureus, indicating an MIC of 31.25 μg/mL, likely due to its high content of alkamides, particularly spilanthol. Several fractions also inhibited bacteria such as P. aeruginosa, S. aureus, and E. coli, possibly because of the presence of alkamides and compounds like β-amyrin.

The present study shows the untargeted metabolite profiling and in vitro antibacterial, cytotoxic, and nitric oxide (NO) inhibitory activities of the methanolic leaves extract (MLE) and methanolic stem extract (MSE) of Erythroxylum mexicanum, as well as the fractions from MSE. Using ultra‐high performance liquid chromatography/quadrupole time‐of‐flight tandem mass spectrometry (UHPLC‐QTOF‐MS/MS), a total of 70 metabolites were identified; mainly alkaloids in the MLE, while the MSE showed a high abundance of diterpenoids. The MSE fractions exhibited differential activity against Gram‐positive bacteria. Notably, the hexane fraction (HSF) against Streptococcus pyogenes ATCC 19615 (MIC=62.5 μg/mL) exhibited a bactericidal effect. The MSE fractions exhibited cytotoxicity against all cancer cell lines tested, with selectivity towards them compared to a noncancerous cell line. Particularly, the HSF and chloroform fraction (CSF) showed the highest cytotoxicity against prostate cancer (PC‐3) cells, with IC₅₀ values of 19.9 and 18.1 μg/mL and selectivity indexes of 3.8 and 4.2, respectively. Both the HSF and ethyl acetate (EASF) fractions of the MSE inhibited NO production in RAW 264.7 macrophages, with NO production percentages of 50.0 % and 51.7 %, respectively, at a concentration of 30 μg/mL. These results indicated that E. mexicanum can be a source of antibacterial, cytotoxic, and anti‐inflammatory metabolites.

The demand for metallic nanoparticles synthesized using green methods has increased due to their various therapeutic and clinical applications, and plant biotechnology may be a potential resource facilitating sustainable methods of AgNPs synthesis. In this study, we evaluate the capacity of extracts from Randia aculeata cell suspension culture (CSC) in the synthesis of AgNPs at different pH values, and their activity against pathogenic bacteria and cancer cells was evaluated. Using aqueous CSC extracts, AgNPs were synthesized with 10% (w/v) of fresh biomass and AgNO₃ (1 mM) at a ratio of 1:1 for 24 h of incubation and constant agitation. UV-vis analysis showed a high concentration of AgNPs as the pH increased, and TEM analysis showed polydisperse nanoparticles with sizes from 10 to 90 nm. Moreover, CSC extracts produce reducing agents such as phenolic compounds (162.2 ± 27.9 mg gallic acid equivalent/100 g biomass) and flavonoids (122.07 ± 8.2 mg quercetin equivalent/100 g biomass). Notably, AgNPs had strong activity against E. coli, S. pyogenes, P. aeruginosa, S. aureus, and S. typhimurium, mainly with AgNPs at pH 6 (MIC: 1.6 to 3.9 µg/mL). AgNPs at pH 6 and 10 had a high antiproliferative effect on cancer cells (IC₅₀ < 5.7 µg/mL). Therefore, the use of cell suspension cultures may be a sustainable option for the green synthesis of AgNPs.