Gabriela Trejo-Tapia

The effects of cold-pretreatment, auxins and carbon source on anther culture of rice

The effects of a cold pretreatment, the concentration of different auxins (2,4-D, NAA and IAA) and the type of carbon source (maltose and sucrose) on the induction of callus from anthers of three parental lines and four rice F1 hybrids (Japonica × Indica, Indica × Japonica) were studied. The results indicated that a cold pretreatment was essential for the induction of callus from anthers of the parental lines and the F1 hybrids. These effects were genotype dependent. Auxins were essential for the induction of callus, and the type and concentration of auxins also influenced this process, as well as the type of carbon source. The greatest induction of callus was by the hybrid Morelos A92 × Koshihikari after a cold pretreatment of 8 days using 10.74 μM α–napthaleneacetic acid and 30 g l−1 maltose.

Influence of cobalt and other microelements on the production of betalains and the growth of suspension cultures of Beta vulgaris

The effects of six microelements (Cu2+, Mn2+, Fe2+, Mo2+, Zn2+, Co2+) on the production of betalains and the growth of suspension cultures of Beta vulgaris were studied. The increase of Co2+ from 1–5 μM resulted in a 60% increment on the production of betalains. A positive effect of this divalent ion was only accomplished when it was added at the beginning of the culture. This was related to a doubling in the specific betalains production rate compared to B5 control medium. No effects on cell growth and ratio of betacyanines to betaxanthines were observed. Mo2+, Fe2+ and Cu2+ presented a positive but less marked effect, while the increase of Mn2+ did not show effects on the production of betalains compared to B5 control medium.

Oxidative stress induces alkaloid production in Uncaria tomentosa root and cell cultures in bioreactors

The effect of oxidative stress on indole alkaloids accumulation by cell suspensions and root cultures of Uncaria tomentosa in bioreactors was investigated. Hydrogen peroxide (H2O2, 200 μM) added to U. tomentosa cell suspension cultures in shaken flasks induced the production of monoterpenoid oxindole alkaloids (MOA) up to 40.0 μg/L. In a stirred tank bioreactor, MOA were enhanced by exogenous H2O2 (200 μM) from no detection up to 59.3 μg/L. Root cultures grew linearly in shaken flasks with a μ=0.045 days−1 and maximum biomass of 12.08±1.24 g DW/L (at day 30). Roots accumulated 3α‐dihydrocadambine (DHC) 2354.3±244.8 μg/g DW (at day 40) and MOA 348.2±32.1 μg/g DW (at day 18). Exogenous addition of H2O2 had a differential effect on DHC and MOA production in shaken flasks. At 200 μM H2O2, MOA were enhanced by 56% and DHC by 30%; while addition of 800 and 1000 μM H2O2, reduced by 30–40% DHC accumulation without change in MOA. Root cultures in the airlift reactor produced extracellular H2O2 with a characteristic biphasic profile after changing aeration. Maximum MOA was 9.06 mg/L at day 60 while at this time roots reached ca. 1 mg/L of DHC. Intracellular H2O2 in root cultures growing in the bioreactor was 0.87 μmol/g DW compared to 0.26 μmol/g DW of shaken flasks cultures. These results were in agreement with a higher activity of the antioxidant enzymes superoxide dismutase and peroxidase by 6‐ and 2‐times, respectively. U. tomentosa roots growing in the airlift bioreactor were exposed to an oxidative stress and their antioxidant system was active allowing them to produce oxindole alkaloids.

In vivo anti-inflammatory and anti-ulcerogenic activities of extracts from wild growing and in vitro plants of Castilleja tenuiflora Benth. (Orobanchaceae).

ETHNOPHARMACOLOGICAL RELEVANCE Castilleja tenuiflora Benth. (Orobanchaceae) is a perennial shrub used since the 16(th) century in Mexican traditional medicine for the treatment of a number of health disorders including inflammation, stomach pain and tumors. The aim of the present study was to evaluate the cytotoxic, anti-inflammatory and anti-ulcerogenic activities of ethyl acetate (EaE), methanol (ME) and aqueous extracts (AE) of Castilleja tenuiflora wild grown (CtW) and in vitro plants (CtIv). MATERIAL AND METHOD Phytochemical analysis of the phenylethanoid glycoside (PhG) and iridoid glycoside (IG) components was carried out by chromatographic methods. In vitro cytotoxic activity of the extracts was evaluated in the following four carcinoma cell lines: colon (HF-6), breast (MCF-7), prostate (PC-3), and nasopharyngeal (KB). The topical anti-inflammatory activity was evaluated in mouse ear edema induced by 12-O-tetradecanoylphorbol-13-acetate (TPA). Anti-ulcerogenic activity was evaluated in rats using an absolute ethanol-induced acute gastric ulcer model. RESULTS The main compounds in the extracts were isoverbascoside, verbascoside and aucubin and their concentration depended both on the solvent used and on the plant material origin. None of the extracts showed cytotoxicity against the tested cell lines. In contrast, CtWEaE, CtWAE and CtIvEaE (1.6 mg/ear) showed moderate anti-inflammatory activity similar to dexamethasone (1 mg/ear) with a 38.2, 39.3 and 49.1% decrease of inflammation, respectively. CtWEaE and CtIvEaE (100 mg/kg) showed high anti-ulcerogenic activity with 88.3 and 83.1% inhibition, respectively, compared to famotidine (20 mg/kg, 32.8% inhibition). CONCLUSION Castilleja tenuiflora extracts provided significant gastric protection in an acute ulcer induction model and topical anti-inflammatory activity in a mouse ear edema model. These activities are related to verbascoside and may explain the traditional use of Castilleja tenuiflora in the treatment of anti-inflammatory and gastrointestinal disorders. Cultured Castilleja tenuiflora plants (in vitro) exhibited pharmacological activities and also have the potential to produce bioactive compounds.

Influence of the culture medium constituents and inoculum size on the accumulation of blue pigment and cell growth of Lavandula spica

AbstractThe effects of the concentration of PO43-, NO3−, Fe 2+, sucrose and inoculum size on the accumulation of blue pigment and growth of suspension cultures of Lavandula spica D.C. (

Monoterpenoid Oxindole Alkaloid Production by Uncaria tomentosa (Willd) D.C. Cell Suspension Cultures in a Stirred Tank Bioreactor

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Analysis of morphological characteristics of Solanum chrysotrichum cell suspension cultures

L. latifolia Vill.), were studied. The combination of 2.5 mM PO43-, 14.1 mM NO3−, 1 mM Fe 2+, 30 g l−1 sucrose and 10 g l−1fresh weight of inoculum, promoted a 7-fold enhancement on the productivity of blue pigment in comparison to the control medium. Among all the culture medium constituents tested, phosphate exerted the highest beneficial effect and Fe2+ showed to be essential for the accumulation of the pigment. High levels of sucrose (60 or 90 g l−1) did not stimulate the accumulation of blue pigment. In these conditions, cell growth and cell viability were drastically affected.

Strictosidine-related enzymes involved in the alkaloid biosynthesis of Uncaria tomentosa root cultures grown under oxidative stress.

Solanum chrysotrichum cell cultures were grown in a stirred tank bioreactor and their rheological and morphological behaviour were evaluated. The culture broths exhibited non-Newtonian and shear-thinning characteristics. Pseudoplasticity of the broths was governed by their biomass concentration. The roundness of aggregates measured as the elliptical form factor (EFF) had important changes. At the beginning of the culture the aggregates with an EFF lower than 2 represented 52% of the population, but in stationary phase the proportion increased to 77%. Whereas the size of aggregates did not change 80% of the population had an area lower than 0.1 mm2. Overall, these results indicate that the shape of the aggregate therefore needs to be considered when studying plant broth rheology.