Eleazar Escamilla-Silva | Instituto Tecnologico de Celaya (original) (raw)

Papers by Eleazar Escamilla-Silva

World Journal of Microbiology & Biotechnology , 1999

Strain H-984 of G. fujikuroi grown for 38 h in a shake¯ask with medium containing 20 g glucose l ... more Strain H-984 of G. fujikuroi grown for 38 h in a shake¯ask with medium containing 20 g glucose l A1 , 3 g yeast extract l A1 , 2.5 g NH 4 NO 3 l A1 , 0.5 g KH 2 PO 4 l A1 , 0.1 g MgSO 4 l A1 , 1 g CaCO 3 l A1 , and inoculated into a bioreactor with medium containing 60 g glucose l A1 ; 1 g NH 4 Cl l A1 ; 3 g KH 2 PO 4 l A1 and 1.5 g MgSO 4 l A1 produced 1100 mg gibberellic acid l A1 .

Phytochemistry, Vol. 42. No. 4, pp. 1105-I 108, 1996, 1996

A new neo-clerodane glycoside, amarisolide, has been isolated from the aerial parts of Salvia ama... more A new neo-clerodane glycoside, amarisolide, has been isolated from the aerial parts of Salvia amarissima. Its structure was established as 2B-0-B-D-glucopyranosyl neo-cleroda-3,13( 16), 14-trien- 15,16-epoxyl& 19-olide by chemical and spectroscopic means.

Gas Separation & Purification , 1993

This paper reports a comparison of several available correlations to calculate flooding velocity ... more This paper reports a comparison of several available correlations to calculate flooding velocity and mass transfer efficiency by using the concept of height equivalent to a theoretical plate (HETP) for distillation columns filled with metallic structured packings. It is found that there are more correlations for pressure drop or gas velocity at flooding than correlations to predict HETP values, and that most of the correlations need empirical constants or exponents for their calculation. Nevertheless, these values are not reported for all the packings and all the sizes available. A case study is made for application of the proposed methods, and the results are presented and compared. A brief comment is made on each method and its ease of application.

Ind. Eng. Chem. Res. , 1993

The recovery of capsaicin from a cell Capsicum annuum culture broth is reported. First, the solid... more The recovery of capsaicin from a cell Capsicum annuum culture broth is reported. First, the solids are removed by filtration, and then liquid-liquid extraction is used to isolate the capsaicin. As observed from a previous study, chloroform was a better solvent than ethyl acetate and ethyl ether, and it was used to extract the capsaicin in a reciprocating Karr column. The extraction studies used a synthetic mixture of capsaicin and water and then cell culture broth. The operating conditions obtained in the pilot plant column are used to design a commercial-size reciprocating column.

new diterpenoid has been isolated from the leaves and fruits of Taxodium mucronatum. Its structur... more new diterpenoid has been isolated from the leaves and fruits of Taxodium mucronatum. Its structure, 8/% hydroxypimar-15-en-19-oic acid, was established by chemical and spectroscopic means.

Phytochemistry, 1980 Vol. 19, pp. 463-464. @ Pergamon Press Ltd. Printed in England., 1980

In a previous communication [l] we reported some ent-beyer-15-ene, ent atis-13-ene and ent-8,5- f... more In a previous communication [l] we reported some ent-beyer-15-ene, ent atis-13-ene and ent-8,5- friedopimar-5-ene derivatives as the major diterpenic constituents of Side&is serrata. A new study of the extract of this plant has now allowed the isolation of three minor diterpenoid acetates, one of which is the known 12-acetyl jativatriol (1, ent-12a acetoxyl/1 b-17-dihydroxy-beyer-15ene) previously found in the species S. reuerchonii [2].

Plant Foods for Human Nutrition, 2017

High antioxidant capacity molecules, such as anthocyanins, occur naturally in blackberry (Rubus f... more High antioxidant capacity molecules, such as anthocyanins, occur naturally in blackberry (Rubus fruticosus). In particular, 'Dasha' blackberry cultivar has scarcely been studied and, it is becoming economically more important in Mexico. In this study, several blackberry extraction conditions, conferred different amounts of detectable phytochemical groups that in turn were analysed with a new approach to investigate their influence on antioxidant capacity (AC). Additionally, a central composite design (CCD) was proposed to study effects of temperature and acidification on AC. Finally, an original approach was used to disclose interactions between the phytochemical content and the AC. Changes in size of the particles during extraction were reported for the first time, and the results showed evidence of swelling and dissolving of particles. UAE of fine and thick powders achieved similar efficiencies in contrast with maceration which showed large differences for the extraction of the tested sizes. CCD showed that low levels of acidification and high levels of temperature resulted in higher extraction of phytochemicals and AC. HPLC show that the main anthocyanidin may represent 88% of the total anthocyanins. Due to its relatively high abundance, cyanidyn-3-glucoside showed evidence of being the main cause of the changes in AC in 'Dasha' extracts. The use of mild conditions resulted in no degradation of anthocyanins and, therefore, there are no AC losses. A correlation plane was proposed to study synergisms of the extracts with other anthocyanins or phenolics.

Biotechnology for Biofuels, Jan 16, 2018

Background: Agave-based alcoholic beverage companies generate thousands of tons of solid residues... more Background: Agave-based alcoholic beverage companies generate thousands of tons of solid residues per year in Mexico. These agave residues might be used for biofuel production due to their abundance and favorable sustainability characteristics. In this work, agave leaf and bagasse residues from species Agave tequilana and Agave salmiana were subjected to pretreatment using the ammonia fiber expansion (AFEX) process. The pretreatment conditions were optimized using a response surface design methodology. We also identified commercial enzyme mixtures that maximize sugar yields for AFEX-pretreated agave bagasse and leaf matter, at ~ 6% glucan (w/w) loading enzymatic hydrolysis. Finally, the pretreated agave hydrolysates (at a total solids loading of ~ 20%) were used for ethanol fermentation using the glucose-and xylose-consuming strain Saccharomyces cerevisiae 424A (LNH-ST), to determine ethanol yields at industrially relevant conditions. Results: Low-severity AFEX pretreatment conditions are required (100-120 °C) to enable efficient enzymatic deconstruction of the agave cell wall. These studies showed that AFEX-pretreated A. tequilana bagasse, A. tequilana leaf fiber, and A. salmiana bagasse gave ~ 85% sugar conversion during enzyme hydrolysis and over 90% metabolic yields of ethanol during fermentation without any washing step or nutrient supplementation. On the other hand, although lignocellulosic A. salmiana leaf gave high sugar conversions, the hydrolysate could not be fermented at high solids loadings, apparently due to the presence of natural inhibitory compounds. Conclusions: These results show that AFEX-pretreated agave residues can be effectively hydrolyzed at high solids loading using an optimized commercial enzyme cocktail (at 25 mg protein/g glucan) producing > 85% sugar conversions and over 40 g/L bioethanol titers. These results show that AFEX technology has considerable potential to convert lignocellulosic agave residues to bio-based fuels and chemicals in a biorefinery.

Bioresources and Bioprocessing, Jan 6, 2017

The present study was conducted to evaluate the feasibility of enzymatic hydrolysis of carotenoid... more The present study was conducted to evaluate the feasibility of enzymatic hydrolysis of carotenoid esters from Tagetes erecta using lipases from the yeast of Yarrowia lipolytica, with the aim of obtaining free lutein. The optimal concentrations of seven nutrients, considering the production of lipases relative to biomass (Y p/x) as the response variable, were determined in flask fermentations. In addition, we studied the effect on hydrolysis of growing Y. lipolytica in the presence of the oleoresin of the marigold flower in flask and stirred tank. Furthermore, hydrolysis of the oleoresin using the lipases from this microorganism was compared with the hydrolysis using lipases from Rhizopus oryzae. Cultured in the presence of marigold oleoresin, Y. lipolytica showed an increase in free carotenoids of 12.41% in flask and 8.8% in stirred tank, representing a fourfold and a threefold increase compared to the initial value in the fermentation, respectively. When lipases from the supernatant from both microorganisms were used for only 14 h hydrolysis experiments, a slight increase was achieved compared to a blank. We concluded that carotenoid esters of the oleoresin could not be completely hydrolyzed in 14 h by these lipases, but that growing Y. lipolytica in the presence of marigold oleoresin gives until fourfold production of free carotenoids in 72 h fermentations.

Food Chemistry, 2008

N-nitrosodimethylamine (NDMA) is a highly active carcinogen that has been detected in trace level... more N-nitrosodimethylamine (NDMA) is a highly active carcinogen that has been detected in trace levels in beers. Solid-phase microextraction (SPME) was used to develop a method for the extraction of NDMA from beer using headspace sampling and gas chromatography with mass ...

Se estudia la cinetica e hidrodinamica de un efluente sanitario domestico, utilizando dos biorrea... more Se estudia la cinetica e hidrodinamica de un efluente sanitario domestico, utilizando dos biorreactores tubulares colocados en serie; el primero opera en condiciones anaerobias y el segundo en aerobias

This article is an open access article distributed under the terms and conditions of the Creative... more This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY

Plants

Agriculture needs to decrease the use of agrochemicals due to their high toxicity and adopt new s... more Agriculture needs to decrease the use of agrochemicals due to their high toxicity and adopt new strategies to achieve sustainable food production. Therefore, nanoparticles (NPs) and plant growth-promoting bacteria (PGPB) have been proposed as viable strategies to obtain better crop yields with less environmental impact. Here, we describe the effect of silica nanoparticles (SiO2-NPs) on survival, antioxidant enzymatic activity, phosphate solubilization capacity, and gibberellin production of Bacillus cereus-Amazcala (B.c-A). Moreover, the effect of the co-application of SiO2-NPs and B.c-A on seed germination, physiological characteristics, and antioxidant enzymatic activity of chili pepper plants was investigated under greenhouse conditions. The results indicated that SiO2-NPs at 100 ppm enhanced the role of B.c-A as PGPB by increasing its phosphate solubilization capacity and the production of GA7. Moreover, B.c-A catalase (CAT) and superoxide dismutase (SOD) activities were increas...

Proc. Harare Symp., IAHS Publ. No. …, 1984

Coal production will increase rapidly in the next 20 years due to the development of large-scale ... more Coal production will increase rapidly in the next 20 years due to the development of large-scale opencast mines. This method of mining disturbs large areas of land which need to be restored following mining. Sediment yield from these areas, can be several hundred times greater than from undisturbed areas. This paper presents an outline of surface erosion problems associated with coal mining operations. Potential sediment control techniques are discussed and a case study for a proposed southern African coal mine is presented. L'érosion du terrain et le contrôle de sédiments en chantiers a ciel ouvert dans 1'Afrique du sud RESUME A cause du développement de très grands chantiers à ciel ouvert la production de charbon augmentera rapidement dans les 20 ans suivants. Cette méthode d'exploitation des mines bouleverse de grandes étendues de terrain et il faut les remettre en état après l'exploitation. La production de sédiments dans ces étendues peut être environ cent fois supérieure à celle observée les zones qui n'ont pas été remuées. Ce rapport présente les grandes lignes des problèmes de l'érosion du terrain dans l'exploitation du charbon. On discute des techniques du contrôle potentiel de sédiment et on présente une étude pour un projet de mine de charbon en Afrique de sud.

World Journal of Microbiology and Biotechnology, 2007

Biotechnology for biofuels, 2018

Agave-based alcoholic beverage companies generate thousands of tons of solid residues per year in... more Agave-based alcoholic beverage companies generate thousands of tons of solid residues per year in Mexico. These agave residues might be used for biofuel production due to their abundance and favorable sustainability characteristics. In this work, agave leaf and bagasse residues from species Agave tequilana and Agave salmiana were subjected to pretreatment using the ammonia fiber expansion (AFEX) process. The pretreatment conditions were optimized using a response surface design methodology. We also identified commercial enzyme mixtures that maximize sugar yields for AFEX-pretreated agave bagasse and leaf matter, at ~ 6% glucan (w/w) loading enzymatic hydrolysis. Finally, the pretreated agave hydrolysates (at a total solids loading of ~ 20%) were used for ethanol fermentation using the glucose- and xylose-consuming strain Saccharomyces cerevisiae 424A (LNH-ST), to determine ethanol yields at industrially relevant conditions. Low-severity AFEX pretreatment conditions are required (100...

Industrial & Engineering Chemistry Research, 1993

The recovery of capsaicin from a cell Capsicum annuum culture broth is reported. First the solids... more The recovery of capsaicin from a cell Capsicum annuum culture broth is reported. First the solids are removed by filtration, and then liquid-liquid extraction is used to isolate the capsaicin. As observed from a previous study, chloroform was a better solvent than ethyl acetate and ...