LXYL-P1-2 immobilized on magnetic nanoparticles and its potential application in paclitaxel production

BACKGROUND: LXYL-P1-2 is the first reported glycoside hydrolase that can catalyze the transformation of 7-b-xylosyl-10-deacetyltaxol (XDT) to 10-deacetyltaxol (DT) by removing the D-xylosyl group at the C7 position. Successful synthesis of paclitaxel by one-pot method combining the LXYL-P1-2 and 10- deacetylbaccatin III-10-b-O-acetyltransferase (DBAT) using XDT as a precursor, making LXYL-P1-2 a highly promising enzyme for the industrial production of paclitaxel. The aim of this study was to investigate the catalytic potential of LXYL-P1-2 stabilized on magnetic nanoparticles, the surface of which was modified by Ni2+-immobilized cross-linked Fe3O4@Histidine. RESULTS: The diameter of matrix was 20­40 nm. The Km value of the immobilized LXYL-P1-2 catalyzing XDT (0.145 mM) was lower than that of the free enzyme (0.452 mM), and the kcat/Km value of immobilized enzyme (12.952 mM s 1 ) was higher than the free form (8.622 mM s 1 ). The immobilized form maintained 50% of its original activity after 15 cycles of reuse. In addition, the stability of immobilized LXYL-P1-2, maintained 84.67% of its initial activity, improved in comparison with free form after 30 d storage at 4 C. CONCLUSIONS: This investigation not only provides an effective procedure for biocatalytic production of DT, but also gives an insight into the application of magnetic material immobilization technology.

Lactobacillus plantarum BL011 cultivation in industrial isolated soybean protein acid residue

Abstract In this study, physiological aspects of Lactobacillus plantarum BL011 growing in a new, all-animal free medium in bioreactors were evaluated aiming at the production of this important lactic acid bacterium. Cultivations were performed in submerged batch bioreactors using the Plackett-Burman methodology to evaluate the influence of temperature, aeration rate and stirring speed as well as the concentrations of liquid acid protein residue of soybean, soy peptone, corn steep liquor, and raw yeast extract. The results showed that all variables, except for corn steep liquor, significantly influenced biomass production. The best condition was applied to bioreactor cultures, which produced a maximal biomass of 17.87 g L-1, whereas lactic acid, the most important lactic acid bacteria metabolite, peaked at 37.59 g L-1, corresponding to a productivity of 1.46 g L-1 h-1. This is the first report on the use of liquid acid protein residue of soybean medium for L. plantarum growth. These results support the industrial use of this system as an alternative to produce probiotics without animal-derived ingredients to obtain high biomass concentrations in batch bioreactors.

Current applications and different approaches for microbial L-asparaginase production

ABSTRACT L-asparaginase (EC 3.5.1.1) is an enzyme that catalysis mainly the asparagine hydrolysis in L-aspartic acid and ammonium. This enzyme is presented in different organisms, such as microorganisms, vegetal, and some animals, including certain rodent's serum, but not unveiled in humans. It can be used as important chemotherapeutic agent for the treatment of a variety of lymphoproliferative disorders and lymphomas (particularly acute lymphoblastic leukemia (ALL) and Hodgkin's lymphoma), and has been a pivotal agent in chemotherapy protocols from around 30 years. Also, other important application is in food industry, by using the properties of this enzyme to reduce acrylamide levels in commercial fried foods, maintaining their characteristics (color, flavor, texture, security, etc.) Actually, L-asparaginase catalyzes the hydrolysis of L-asparagine, not allowing the reaction of reducing sugars with this aminoacid for the generation of acrylamide. Currently, production of L-asparaginase is mainly based in biotechnological production by using some bacteria. However, industrial production also needs research work aiming to obtain better production yields, as well as novel process by applying different microorganisms to increase the range of applications of the produced enzyme. Within this context, this mini-review presents L-asparaginase applications, production by different microorganisms and some limitations, current investigations, as well as some challenges to be achieved for profitable industrial production.

Current applications and different approaches for microbial L-asparaginase production

ABSTRACT L-asparaginase (EC 3.5.1.1) is an enzyme that catalysis mainly the asparagine hydrolysis in L-aspartic acid and ammonium. This enzyme is presented in different organisms, such as microorganisms, vegetal, and some animals, including certain rodent's serum, but not unveiled in humans. It can be used as important chemotherapeutic agent for the treatment of a variety of lymphoproliferative disorders and lymphomas (particularly acute lymphoblastic leukemia (ALL) and Hodgkin's lymphoma), and has been a pivotal agent in chemotherapy protocols from around 30 years. Also, other important application is in food industry, by using the properties of this enzyme to reduce acrylamide levels in commercial fried foods, maintaining their characteristics (color, flavor, texture, security, etc.) Actually, L-asparaginase catalyzes the hydrolysis of L-asparagine, not allowing the reaction of reducing sugars with this aminoacid for the generation of acrylamide. Currently, production of L-asparaginase is mainly based in biotechnological production by using some bacteria. However, industrial production also needs research work aiming to obtain better production yields, as well as novel process by applying different microorganisms to increase the range of applications of the produced enzyme. Within this context, this mini-review presents L-asparaginase applications, production by different microorganisms and some limitations, current investigations, as well as some challenges to be achieved for profitable industrial production.

Study on simultaneous extraction and purification technology of glycyrrhizin acid and liquiritin based on ceramic membrane ultrafiltration technology / 中草药

Objective: To establish an extraction and purification process line synchronization suitable for industrial production of glycyrrhizin acid and liquiritin. Methods: The extraction rates of glycyrrhizic acid and liquiritin were as indexes, orthogonal test was performed to determine the optimum conditions; The retention rate of glycyrrhizic acid and liquiritin and impurity removal rates were as indexes, the best ultrafiltration process parameters were optimized by orthogonal test. Results: The optimum extraction conditions were as follows: 0.75% ammonia water (24 times), extracted for three times, each time under 60 min, average rates of glycyrrhizic acid and liquiritin were 98.3% and 72.3%; The best ultrafiltration process parameters: 10 nm inorganic ceramic membrane, pressure of 0.12 MPa, temperature of 25℃. The average retention rates of glycyrrhizic acid and liquiritin were 99.3% and 98.9%, and an average removal rate of impurity was 23.3%. Conclusion: The experiment adopted the joint application of inorganic ceramic membrane ultrafiltration technology and ammonia extraction process, and it has realized the glycyrrhizic acid and licorice glycosides extraction and purification of synchronization; The process has low production cost and good safety, and is suitable for industrial application.

Condições higiênico-sanitárias e composição nuticional de salames artesanais e industrializados: uma comparação / Conditions sanitary and nutritional quality of handmade salami and industrialized: a comparaction

O salame tipo colonial é um produto de grande aceitação na região sudoeste do Paraná, especialmente, por fazer parte da tradição de origem italiana e pela cultura na produção de suínos. Tradicionalmente, o salame tipo colonial é produzido de forma artesanal, no próprio domicílio ou pequenas indústrias, sendo comercializado em feiras, supermercados e bancas de produtos coloniais em rodovias. A contaminação desses produtos pode ser proveniente da utilização de matérias-primas contaminadas ou por manipulação inadequada antecedente ao consumo. O fato de, normalmente, o produto ser consumido sem cozimento prévio, pode ser considerado um potencial risco a saúde do consumidor. Com o intuito de conhecer a qualidade dos salames coloniais e salames industrializados comercializados na região sudoeste paranaense, realizou-se análises físico-químicas e microbiológicas. Os resultados demonstraram que, enquanto os salames industrializados se encontravam de acordo com a legislação brasileira quanto aos parâmetros físico-químicos e microbiológicos, os salames artesanais apresentaram teores de umidade e de proteínas em discordância com a legislação pertinente, bem como 16,67% das amostras apresentaram-se contaminadas por Coliformes a 45°C e 22,22% por Salmonella ssp., indicando que é um problema sanitário que carece atenção em nível nacional, uma vez que em estudos anteriores, ficou comprovada a contaminação de salames artesanais de várias regiões do país por microrganismos patogênicos.

Colonial-type salami is a widely accepted product in the southwestern region of Paraná, especially as part of the Italian tradition and its culture in pig production. Traditionally, the colonial-type salami is handmade in the farmer's house or in small industries, being marketed in fairs, supermarkets and colonial product stands along the roads. The contamination of these products can happen due to the use of contaminated raw materials or by poor handling prior to consumption. The fact that the product is usually consumed without prior cooking can be considered a potential risk to consumer's health. In order to evaluate the quality of industrialized salami and colonial salami marketed in the southwestern region of Paraná, a physical-chemical and microbiological analysis was performed. The results showed that while the industrial salami was manufactured in accordance with the Brazilian law regarding the physical-chemical and microbiological parameters, the handmade salami presented moisture and protein levels in disagreement with the relevant legislation, as well as 16.67% of the samples presented contamination by coliforms at 45 °C. They also presented 22.22% of the samples contaminated by Salmonella spp., indicating that this is a health issue that needs to be addressed at a national level, since it can be seen in previous studies that handmade salami presented contamination by pathogenic microorganisms in several regions of the country.

Extraction and purification technology for different extracts from Lamiophlomis rotata in industrialization / 中草药

Objective: The macroporous adsorptive resin chromatographic column combining with polyamide chromatographic column was used to separate the flavonoides, phenylethanoidglycosides, iridoid glycosides, and high polarity ingredients (such as alkaloid salts and sugars) in industrialization. Methods: Water extract from Lamiophlomis rotata (WELR) was separated and enriched by series and parallel method of polyamide and macroporous adsorptive resins and CCPP serial laminar analysis, and was ultrafiltrated by LM-125 ultrafiltration apparatus, then was dried under the reduced pressure by JYT-50 LN multipurpose kinesis back flow extract concentration subassembly. WELR, 70% ethanol solution eluate I (70% ethanol solution eluted polyamide column), 70% ethanol solution eluate II (70% ethanol solution eluting macroporous resin column), and ultrafiltration matter. The total flavonoids and total phenylethanoid glycosides were determined by aluminum nitrate-sodium nitrite UV spectrophotometry. The total iridoid glycosides were determined by the first derivative spectrophotometry. Shanzhiside methylester and 8-O-acetyl shanzhiside methylester were determined and the changes of total iridoid glycosides ingredients were investigated in the different elution requirement by HPLC. Results: Ethanol (70%) was used as dissolvent. Using the "introduction from superior surface" sample introduction mode and "introduction from superior surface" eluting mode in polyamide chromatographic column, the "introduction from inferior surface" sample introduction mode and "introduction from superior surface" eluting mode in the macroporous adsorptive resin chromatographic column, yields of 70% ethanol solution eluate I, 70% ethanol solution eluate II, and ultrafiltration matter were 2.43%, 20.80%, and 82.60%, respectively. Conclusion: This production technology may transform the experimental achievement to industrial production successfully.