Litsea glaucescens Kuth possesses bactericidal activity against Listeria monocytogenes.

Background: Litsea glaucencens Kuth is an aromatic plant used for food seasoning food and in Mexican traditional medicine. Among, L. glaucencens leaves properties, it has proven antibacterial activity which can be used against opportunistic pathogens like Listeria monocytogenes, a foodborne bacteria that is the causal agent of listeriosis, a disease that can be fatal in susceptible individuals. The aim of this work was to investigate the antibacterial activity of L. glaucescens Kuth leaf extracts against L. monocytogenes and to identify its bioactive components. Material and Methods: L. glaucences leaves were macerated with four solvents of different polarity (n-hexane, dichloromethane, ethyl acetate, and methanol). To determine the capacity to inhibit bacterial proliferation in vitro, agar diffusion and microdilution methods were used. Next, we determined the minimal bactericidal concentration (MBC). Finally, we determined the ratio of MBC/MIC. Metabolites present in the active methanolic extract from L. glaucescens Kuth (LgMeOH) were purified by normal-phase open column chromatography. The structure of the antibacterial metabolite was determined using nuclear magnetic resonance (1H, 13C, COSY, HSQC) and by comparison with known compounds. Results: The LgMeOH extract was used to purify the compound responsible for the observed antimicrobial activity. This compound was identified as 5,7-dihydroxyflavanone (pinocembrin) by analysis of its spectroscopic data and comparison with those described. The MIC and MBC values obtained for pinocembrin were 0.68 mg/mL, and the ratio MBC/MIC for both LgMeOH and pinocembrin was one, which indicates bactericidal activity. Conclusion: L. glaucences Kuth leaves and its metabolite pinocembrin can be used to treat listeriosis due the bactericidal activity against L. monocytogenes.

High variability of perezone content in rhizomes of Acourtia cordata wild plants, environmental factors related, and proteomic analysis.

With the aim of exploring the source of the high variability observed in the production of perezone, in Acourtia cordata wild plants, we analyze the influence of soil parameters and phenotypic characteristics on its perezone content. Perezone is a sesquiterpene quinone responsible for several pharmacological effects and the A. cordata plants are the natural source of this metabolite. The chemistry of perezone has been widely studied, however, no studies exist related to its production under natural conditions, nor to its biosynthesis and the environmental factors that affect the yield of this compound in wild plants. We also used a proteomic approach to detect differentially expressed proteins in wild plant rhizomes and compare the profiles of high vs. low perezone-producing plants. Our results show that in perezone-producing rhizomes, the presence of high concentrations of this compound could result from a positive response to the effects of some edaphic factors, such as total phosphorus (Pt), total nitrogen (Nt), ammonium (NH4), and organic matter (O. M.), but could also be due to a negative response to the soil pH value. Additionally, we identified 616 differentially expressed proteins between high and low perezone producers. According to the functional annotation of this comparison, the upregulated proteins were grouped in valine biosynthesis, breakdown of leucine and isoleucine, and secondary metabolism such as terpenoid biosynthesis. Downregulated proteins were grouped in basal metabolism processes, such as pyruvate and purine metabolism and glycolysis/gluconeogenesis. Our results suggest that soil parameters can impact the content of perezone in wild plants. Furthermore, we used proteomic resources to obtain data on the pathways expressed when A. cordata plants produce high and low concentrations of perezone. These data may be useful to further explore the possible relationship between perezone production and abiotic or biotic factors and the molecular mechanisms related to high and low perezone production.

Cytotoxic Activity of Wild Plant and Callus Extracts of Ageratina pichinchensis and 2,3-Dihydrobenzofuran Isolated from a Callus Culture.

Ageratina pichinchensis (Kunth) R.M. King & H. Rob. belongs to the Asteraceae family and is a plant native to Mexico to which several biological properties are attributed. In this study, the cytotoxic effect of four extracts from the wild plants and two extracts from A. pichinchensis callus culture were evaluated against carcinogenic cell lines including prostate carcinoma, cervical cancer, hepatocellular carcinoma, hepatoma human, lung cancer, and cellular keratinocytes. The extracts were obtained with ethyl acetate and methanol using both leaves and stems or the callus. Only the ethyl acetate extract of the callus culture influenced the cervical cancer cell line (HeLa) with an IC50 of 94.79 ± 2.0 µg/mL. From the ethyl acetate callus extract, 2,3-dihydrobenzofuran was isolated and purified and also evaluated against cancer cells. The cytotoxic evaluation of this compound showed a significant effect against the HeLa cell line with an IC50 of 23.86 ± 2.5 µg/mL. Our results contribute to the development of biotechnological alternatives and extraction processes to produce compounds with possible potential against certain types of human cancer.

Obtaining 2,3-Dihydrobenzofuran and 3-Epilupeol from Ageratina pichinchensis (Kunth) R.King & Ho.Rob. Cell Cultures Grown in Shake Flasks under Photoperiod and Darkness, and Its Scale-Up to an Airlift Bioreactor for Enhanced Production.

Ageratina pichinchensis (Kunth) R.King & Ho.Rob. is a plant used in traditional Mexican medicine, and some biotechnological studies have shown that its calluses and cell suspension cultures can produce important anti-inflammatory compounds. In this study, we established a cell culture of A. pichinchensis in a 2 L airlift bioreactor and evaluated the production of the anti-inflammatory compounds 2,3-dihydrobenzofuran (1) and 3-epilupeol (2). The maximum biomass production (11.90 ± 2.48 g/L) was reached at 11 days of culture and cell viability was between 80% and 90%. Among kinetic parameters, the specific growth rate (µ) was 0.2216 days-1 and doubling time (td) was 3.13 days. Gas chromatography coupled with mass spectrometry (GC-MS) analysis of extracts showed the maximum production of compound 1 (903.02 ± 41.06 µg/g extract) and compound 2 (561.63 ± 10.63 µg/g extract) at 7 and 14 days, respectively. This study stands out for the significant production of 2,3-dihydrobenzofuran and 3-epilupeol and by the significant reduction in production time compared to callus and cell suspension cultures, previously reported. To date, these compounds have not been found in the wild plant, i.e., its production has only been reported in cell cultures of A. pichinchensis. Therefore, plant cell cultured in an airlift reactor can be an alternative for the improved production of these anti-inflammatory compounds.

Phytochemical, Pharmacological, and Biotechnological Study of Ageratina pichinchensis: A Native Species of Mexico.

Ageratina pichinchensis (Asteraceae) has been used for a long time in traditional Mexican medicine for treating different skin conditions and injuries. This review aimed to provide an up-to-date view regarding the traditional uses, chemical composition, and pharmacological properties (in vitro, in vivo, and clinical trials) that have been achieved using crude extracts, fractions, or pure compounds. Moreover, for a critical evaluation of the published literature, key databases (Pubmed, Science Direct, and SciFinder, among others) were systematically searched using keywords to retrieve relevant publications on this plant. Studies that reported on crude extracts, fractions, or isolated pure compounds of A. pichinchensis have found a varied range of biological effects, including antibacterial, curative, antiulcer, antifungal, and anti-inflammatory activities. Phytochemical analyses of different parts of A. pichinchensis revealed 47 compounds belonging to chromenes, furans, glycosylated flavonoids, terpenoids, and essential oils. Furthermore, biotechnological studies of A. pichinchensis such as callus and cell suspension cultures have provided information for future research perspectives to improve the production of valuable bioactive compounds.

Establishment of a Cell Suspension Culture of Ageratina pichinchensis (Kunth) for the Improved Production of Anti-Inflammatory Compounds.

Ageratina pichinchensis (Kunth) is a plant used in traditional Mexican medicine to treat multiple ailments. However, there have not been biotechnological studies on producing compounds in in vitro cultures. The aim of this study was to establish a cell suspension culture of A. pichinchensis, quantify the anti-inflammatory constituents 2,3-dihydrobenzofuran (2) and 3-epilupeol (3), evaluate the anti-inflammatory potential of its extracts, and perform a phytochemical analysis. Cell suspension cultures were established in a MS culture medium of 30-g L-1 sucrose, 1.0-mg L-1 α-naphthaleneacetic acid, and 0.1-mg L-1 6-furfurylaminopurine. The ethyl acetate extract of the cell culture analyzed by gas chromatography (GC) revealed that the maximum production of anti-inflammatory compounds 2 and 3 occurs on days eight and 16, respectively, improving the time and previously reported yields in callus cultures. The anti-inflammatory activity of these extracts exhibited a significant inhibition of nitric oxide (NO) production. Furthermore, a phytochemical study of the ethyl acetate (EtOAc) and methanol (MeOH) extracts from day 20 led to the identification of 17 known compounds. The structures of the compounds were assigned by an analysis of 1D and 2D NMR data and the remainder by GC-MS. This is the first report of the production of (-)-Artemesinol, (-)-Artemesinol glucoside, encecalin, and 3,5-diprenyl-acetophenone by a cell suspension culture of A. pichinchensis.

Improved production, purification, and characterization of biosurfactants produced by Serratia marcescens SM3 and its isogenic SMRG-5 strain.

In this study, the biosurfactants (Bs) production of two Serratia marcescens strains (SM3 and its isogenic SMRG-5 strain) was improved and the tenso-active agents were purified and characterized. A 23 factorial design was used to evaluate the effect of nitrogen and carbon sources on the surface tension (ST) reduction and emulsion index (EI24 ) of the produced Bs. Optimum Bs production by SM3 was achieved at high concentrations of carbon and nitrogen, reducing ST to 26.5 ± 0.28 dynes/cm, with an EI24 of 79.9 ± 0.2%. Meanwhile, the best results for SMRG-5 were obtained at low concentrations, reducing the ST to 25.2 ± 0.2 dynes/cm, with an EI24 of 89.7 ± 0.28%. The optimal conditions for Bs production were scaled up in a 2-L reactor, yielding 4.8 and 5.2 g/L for SM3 and SMRG-5, respectively. Gas Chromatography-Mass Spectrometry (GC-MS) analysis revealed the presence of two different lipopeptides (hidrofobic fractions: octadecanoic and hexadecanoic acid for SM3 and SMRG5, respectively). Both strains were capable of benzo [a] pyrene removal (59% after 72 H of culture).

Phenolic Compounds Isolated from Caesalpinia coriaria Induce S and G2/M Phase Cell Cycle Arrest Differentially and Trigger Cell Death by Interfering with Microtubule Dynamics in Cancer Cell Lines.

Caesalpinia coriaria (C. coriaria), also named cascalote, has been known traditionally in México for having cicatrizing and inflammatory properties. Phytochemical reports on Caesalpinia species have identified a high content of phenolic compounds and shown antineoplastic effects against cancer cells. The aim of this study was to isolate and identify the active compounds of a water:acetone:ethanol (WAE) extract of C. coriaria pods and characterize their cytotoxic effect and cell death induction in different cancer cell lines. The compounds isolated and identified by chromatography and spectroscopic analysis were stigmasterol, ethyl gallate and gallic acid. Cytotoxic assays on cancer cells showed different ranges of activities. A differential effect on cell cycle progression was observed by flow cytometry. In particular, ethyl gallate and tannic acid induced G2/M phase cell cycle arrest and showed interesting effect on microtubule stabilization in Hep3B cells observed by immunofluorescence. The induction of apoptosis was characterized by morphological characteristic changes, and was supported by increases in the ratio of Bax/Bcl-2 expression and activation of caspase 3/7. This work constitutes the first phytochemical and cytotoxic study of C. coriaria and showed the action of its phenolic constituents on cell cycle, cell death and microtubules organization.

Cytotoxic Activity and Chemical Composition of the Root Extract from the Mexican Species Linum scabrellum: Mechanism of Action of the Active Compound 6-Methoxypodophyllotoxin.

The cytotoxic activity and the chemical composition of the dichloromethane/methanol root extract of Linum scabrellum Planchon (Linaceae) were analyzed. Using NMR spectra and mass spectrometry analyses of the extract we identified eight main constituents: oleic acid (1), octadecenoic acid (2), stigmasterol (3), α-amyrin (4), pinoresinol (5), 6 methoxypodophyllotoxin (6), coniferin (7), and 6-methoxypodophyllotoxin-7-O-ß-D-glucopyranoside (8). By using the sulforhodamine B assay, an important cytotoxic activity against four human cancer cell lines, HF6 colon (IC50 = 0.57 µg/mL), MCF7 breast (IC50 = 0.56 µg/mL), PC3 prostate (IC50 = 1.60 µg/mL), and SiHa cervical (IC50 = 1.54 µg/mL), as well as toward the normal fibroblasts line HFS-30 IC50 = 1.02 µg/mL was demonstrated. Compound 6 (6-methoxypodophyllotoxin) was responsible for the cytotoxic activity exhibiting an IC50 value range of 0.0632 to 2.7433 µg/mL against the tested cell lines. Cell cycle studies with compound 6 exhibited a cell arrest in G2/M of the prostate PC3 cancer cell line. Microtubule disruption studies demonstrated that compound 6 inhibited the polymerization of tubulin through its binding to the colchicine site (binding constant K b = 7.6 × 10(6) M(-1)). A dose-response apoptotic effect was also observed. This work constitutes the first investigation reporting the chemical composition of L. scabrellum and the first study determining the mechanism of action of compound 6.

Regioselective glucosylation of inositols catalyzed by Thermoanaerobacter sp. CGTase.

Monoglucosylated products of L-chiro-, D-chiro-, muco-, and allo-inositol were synthesized by regioselective α-D-glucosylation with cyclodextrin glucosyl transferase from Thermoanaerobacter sp. after hydrolysis of by products with Aspergillus niger glucoamylase. While the reactions carried out with D-chiro-, muco-, and allo-inositol resulted in the regioselective formation of monoglucosylated products, two products were obtained in the reaction with L-chiro-inositol. Through the structural characterization of the glucosylated inositols here we demonstrated that the selectivity observed in the glucosylation of several inositols by Thermoanaerobacter sp. CGTase, is analogous to the specificity observed for the glucosylation of ß-D-glucopyranose and equivalent glucosides.

Mycological and electron microscopic study of Solanum chrysotrichum saponin SC-2 antifungal activity on Candida species of medical significance.

Solanum chrysotrichum is utilized in traditional Mexican medicine for the treatment of mycotic skin infections. Several microbiological studies have provided evidence of its antifungal activity against dermatophytes and yeasts. S. chrysotrichum saponins have been identified as a group of compounds with antifungal activity and saponin SC-2 has demonstrated to be the most active. Previous clinical studies have shown the therapeutic effectiveness of S. chrysotrichum-derived saponin-standardized herbal products in the treatment of Tinea pedis and Pityriasis capitis. There is no previous evidence of the activity of these saponins against Candida non-albicans species, or fluconazole- and ketoconazole-resistant Candida strains. The present study reports the biological activity of the SC-2 saponin (inhibitory concentration [IC (50)] and minimum fungicide concentration [MFC]), against 12 Candida strains of clinical significance ( C. albicans, five strains; C. glabrata and C. parapsilosis, two; C. krusei, C. lusitaniae and C. tropicalis, one), including some fluconazole (Fluco)- and ketoconazole (Keto)-resistant clinical isolates. In addition, SC-2-associated microstructural alterations were reported in four of the above-mentioned Candida species. Seven strains had IC (50) of 200 microg/mL for SC-2, 400 microg/mL was found in four strains, and 800 microg/mL for a sole C. glabrata strain. Susceptibility to SC-2 saponin was as follows: C. albicans = C. lusitaniae > C. krusei > C. glabrata. The MFC was 800 microg/mL for the majority of strains (nine), 400 microg/mL for C. albicans (two strains) and C. lusitaniae. The ultrastructural Candida changes originated by SC-2 included the following: 1) damage on cytoplasmic membrane and organelles; 2) changes in cell wall morphology and density, with separation of cytoplasmatic membrane from cell wall and disintegration of the latter; and 3) total degradation of cellular components and death. Changes were manifested from 6 h of incubation, reaching their maximum effect at 48 h. In conclusion, the saponin SC-2 possesses fungicide and fungistatic activity on different Candida albicans and non- albicans species (including some azole-resistant strains) with IC (50) values of 200 microg/mL (in Fluco-susceptible strains) and of 400 - 800 mug/mL (in Fluco-resistant strains). Additionally, we observed by transmission electron microscopy (TEM) that saponin SC-2 causes severe changes in all fungal cell membranes, and to a lesser degree on the cell wall.