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Objectives: The purpose of this study is to investigate the effect of aspirin on epithelial HPV16-transformed cells and its anti-tumor effects, in an experimental HPV 16 positive tumor model. Design: The design of the study is experimental (in vitro and in vivo). Participants/Materials, Setting, and Methods: SiHa and BMK-16/myc cells were treated with aspirin and cell proliferation was determined by MTT; Caspase-Glo 3/7 Assay was used to determine apoptosis. The tumor-bearing mice group was treated with 50 mg/gr/day of aspirin (orally) during 30 days and the antitumor effect was determined. Results: Here we provide evidence that aspirin has a negative effect on proliferation and induces apoptosis in the human (SiHa) and murine (BMK-16/myc) HPV16-cells. Furthermore, aspirin showed inhibition of tumor growth, and in mice treated with aspirin prior to implantation of tumor cells, the tumor growth was delayed. Also, the effect of aspirin increased survival in tumor-bearing mice and in mice pre-treated with aspirin. Limitations: It is necessary to carry out in vitro and in vivo studies of the molecular mechanisms involved in the effects of aspirin on tumor cells. Conclusion: Aspirin showed antiproliferative effects in tumor cells and inhibited tumor progression and could be effective as a chemopreventive agent. Thus, aspirin deserves further exploration for the treatment of cervical cancer and other neoplasms.

BACKGROUND Single-cell oils obtained from oleaginous microorganisms by using lignocellulosic waste hydrolysates are an alternative for producing biodiesel. AIMS To isolate a yeast strain able to produce lipids from centrifuged nejayote (CN), hydrolyzed nejayote solids (HNS) and hydrolyzed sugarcane bagasse (HSB). METHODS In order to identify the yeasts recovered, 26S ribosomal DNA was sequenced. The metabolic profile was assessed by using API20C AUX strips. The nutritional characterization of CN, HNS and HSB was performed by quantifying reducing sugars, total carbohydrates, starch, protein and total nitrogen. The biomass and lipid production ability were evaluated by performing growth kinetics of Clavispora lusitaniae Hi2 in combined culture media. RESULTS Six oleaginous yeast strains were isolated and identified, selecting C. lusitaniae Hi2 to study its lipids production by using nejayote. The C. lusitaniae Hi2 strain can use glucose, xylose, arabinose, galactose and cellobiose as carbon sources. Cultures of C. lusitaniae Hi2 presented the best biomass (5.6±0.28 g/L) and lipid production (0.99±0.09 g/L) at 20 h of incubation with the CN:HNS media in the 25:75 and 50:50 ratios, respectively. CONCLUSIONS The use of CN, HNS and HSB for the growth of C. lusitaniae Hi2 is an option to take advantage of these agro-industrial residues and generate compounds of biotechnological interest.

This study analyzed the thermostability and effect of calcium ions on the enzymatic activity of α-amylase produced by Bacillus licheniformis strain LB04 isolated from Espinazo Hot springs in Nuevo Leon, Mexico. The enzyme was immobilized by entrapment on agar-agarose beads, with an entrapment yield of 19.9%. The identification of the bacteria was carried out using 16s rDNA sequencing. The enzyme was purified through ion exchange chromatography (IEX) in a DEAE-Sephadex column, revealing a protein with a molecular weight of ≈130 kDa. The enzyme was stable at pH 3.0 and heat stable up to 80 °C. However, the optimum conditions were reached at 65 °C and pH 3.0, with a specific activity of 1851.7 U mg−1 ± 1.3. The agar-agarose immobilized α-amylase had a hydrolytic activity nearly 25% higher when compared to the free enzyme. This study provides critical information for the understanding of the enzymatic profile of B. licheniformis strain LB04 and the potential application of the microorganisms at an industrial level, specifically in the food industry.

Single-cell oils obtained from oleaginous microorganisms by using lignocellulosic waste hydrolysates are an alternative for producing biodiesel.To isolate a yeast strain able to produce lipids from centrifuged nejayote (CN), hydrolyzed nejayote solids (HNS) and hydrolyzed sugarcane bagasse (HSB).In order to identify the yeasts recovered, 26S ribosomal DNA was sequenced. The metabolic profile was assessed by using API20C AUX strips. The nutritional characterization of CN, HNS and HSB was performed by quantifying reducing sugars, total carbohydrates, starch, protein and total nitrogen. The biomass and lipid production ability were evaluated by performing growth kinetics of Clavispora lusitaniae Hi2 in combined culture media.Six oleaginous yeast strains were isolated and identified, selecting C. lusitaniae Hi2 to study its lipids production by using nejayote. The C. lusitaniae Hi2 strain can use glucose, xylose, arabinose, galactose and cellobiose as carbon sources. Cultures of C. lusitaniae Hi2 presented the best biomass (5.6±0.28 g/L) and lipid production (0.99±0.09 g/L) at 20 h of incubation with the CN:HNS media in the 25:75 and 50:50 ratios, respectively.The use of CN, HNS and HSB for the growth of C. lusitaniae Hi2 is an option to take advantage of these agro-industrial residues and generate compounds of biotechnological interest.

A full-length cDNA encoding for 1-SST in Agave tequilana Weber var. azul. was isolated, cloned and expressed in Pichia pastoris. The heterologous protein, with a molecular mass of 75 kDa, shows identity with different plant fructosyltransferases and invertases, which belong to the glycoside hydrolase 32 family. When sucrose was used as substrate, only the transference products 1-kestose and glucose were identified, while from 1-kestose, nystose and fructose were obtained as transference and hydrolysis products respectively, with sucrose as a secondary product. The enzyme has a low turnover number (260 min−1) at 30 °C, with optimal stability at 25 °C and pH 5.5. In order to identify the probable residues involved in the active site, a three-dimensional model was built using the fructan 1-exohydrolase IIa from Cichorium intybus (PDB entry 1st8) as template. This is the first report concerning cloning and expression of an Agave fructosyltransferase.

Agave plants have been part of human food and rituals since Mesoamerican civilizations and are now the raw material of distilled spirit beverages like tequila and mezcal. Nevertheless, they are also a natural source of fructans, known as agavins that may be considered the functional components of both traditional products such as aguamiel and pulque, and neutraceuticals for the formulation of functional products. In this chapter the structure, biosynthesis and nutritional properties of agave fructans are reviewed, as well as the main unit operations involved in new processing alternatives. Finally the market potential for agavins is discussed.

A Leuconostoc mesenteroides NRRL B-512 F levansucrase gene, (levS), was isolated, sequenced and cloned in Escherichia coli. The recombinant enzyme was shown to be a fructosyltransferase producing a polymer identified by 13C-NMR as levan. Based on sequence analysis, we found that this levansucrase is a mosaic protein, bearing structural features of glucosyltransferases in the amino and carboxy terminal regions similarly to inulosucrase from Leuconostoc citreum. The phylogenetic analysis of the C-terminal region domain of levansucrases from L. mesenteroides demonstrates that they group together into a novel putative sub-family of genes and evolved long before all other glucosyltransferases, while their catalytic domain structure is species related.