Covalent Immobilization of Lipase in Residual Yerba Mate Stick (Ilex paraguariensis A. St.-Hil.)

The objective of this study was to immobilize Eversa® Transform 2.0 lipase on residual yerba mate stick. The stick went through an alkaline pre-treatment and different activation treatments (APTS/glutaraldehyde and sodium metaperiodate). Immobilization was performed using hexane solvent and ammonium nitrate buffer. Support characterization, esterification activity, immobilized enzyme characterization, and operational stability were performed. Characterization by SEM demonstrated that the activation treatments were efficient. The immobilization of lipase on APTS/glutaraldehyde activated support showed a yield of 225.52 % and metaperiodate 162.76 %, using hexane as solvent. Good operational stability of the immobilized lipase was observed both in support activated with APTS / glutaraldehyde (8 recycles) and in support activated with metaperiodate (5 recycles), maintaining the activity of 65.62% and 52.00% in concern to the activity initial, respectively. The optimal reaction temperature was 40 ºC for the free and immobilized enzyme. Km and Vmáx values were 16.55 μmol.g-1 and 5555.56 μmol.g-1.min-1 for free enzyme; 33.52 μmol.g-1 and 4761.9 μmol.g-1.min-1 for immobilized enzyme, respectively. The parameters of thermal inactivation confirmed a better thermostability of the lipase in free form.

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Biocatalytic Epoxidation of Cyclooctene to 1,2-Epoxycyclooctane by a Newly Immobilized Aspergillus niger Lipase

Catalysts ◽

10.3390/catal10070781 ◽

2020 ◽

Vol 10 (7) ◽

pp. 781

Author(s):

Qingsheng Chen ◽

Fei Peng ◽

Fangzhou Li ◽

Gaohui Xia ◽

Minhua Zong ◽

...

Keyword(s):

Aspergillus Niger ◽

Ethyl Acetate ◽

Immobilized Enzyme ◽

Immobilized Lipase ◽

Enantiomeric Excess ◽

Reaction System ◽

Product Yield ◽

Operational Stability ◽

Reaction Conditions ◽

Optimum Reaction

A newly immobilized Aspergillus niger lipase (ANL@ZnGlu-MNPs) was employed for the preparation of 1,2-epoxycyclooctane by oxidation of cyclooctene. The chosen variables, including substrate concentration, reaction temperature, immobilized enzyme dose, and H2O2 dose, were optimized in the reaction system of ethyl acetate. The yield and the enantiomeric excess of the product were achieved at 56.8% and 84.1%, respectively, under the following optimum reaction conditions: the concentration of substrate (cyclooctene) was 150 mM, the dosages of immobilized enzyme (ANL@ZnGlu-MNPs) and hydrogen peroxide were respectively 100 mg and 4.4 mmol, and the reaction was carried out in the system of 4 mL ethyl acetate at 40 °C. Further study on the operational stability of ANL@ZnGlu-MNPs showed that more than 51.6% of product yield was obtained after reusing for ten batches. A novel immobilized lipase was prepared and applied to synthesize 1,2-epoxycyclooctane from cyclooctene. Although ANL@ZnGlu-MNPs performs well in operational stability and the reaction can achieve high enantiomeric purity of the product, the yield of the catalytic reaction needs to be further improved.

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Bisepoxide-activated Hollow Silica Microspheres for Covalent Immobilization of Lipase from Burkholderia cepacia

Periodica Polytechnica Chemical Engineering ◽

10.3311/ppch.12665 ◽

2019 ◽

Author(s):

Flóra Nagy ◽

Kinga Szabó ◽

Péter Bugovics ◽

Gábor Hornyánszky

Keyword(s):

Burkholderia Cepacia ◽

Kinetic Resolution ◽

Immobilized Lipase ◽

Covalent Immobilization ◽

Diglycidyl Ether ◽

Free Form ◽

Flow Mode ◽

Silica Microspheres ◽

Batch Mode ◽

Hollow Silica

An efficient and easy-to-perform method was developed for covalent immobilization of lipase from Burkholderia cepacia (Lipase PS) on hollow silica microspheres (M540) by bisepoxide activation. For immobilization, various bisepoxides of different length, rigidity and hydrophobicity in their linkers were applied to activate the amino groups on the M540 support. Effect of the individual bisepoxides on the catalytic performance of the immobilized Lipase PS was studied by using lipase-catalyzed kinetic resolution (KR) of racemic 1-phenylethanol (rac-1) with vinyl acetate in batch mode. Catalytic activity, enantiomer selectivity, recyclability and thermal stability of the new immobilized Lipase PS biocatalysts were investigated. The optimal enzyme / support ratio with the support activated by the most efficient bisepoxide, i.e. poly(ethylene glycol) diglycidyl ether (PDE), was 1:5. The most efficient Lipase PS on PDE activated M540 showed an almost five fold higher biocatalytic activity value (rbatch = 42.8 U/g) with enhanced selectivity (ee(R)-2 = 99.1 %) to the free form of Lipase PS (rbatch = 9.0 U/g; ee(R)-2 = 98.9 %). The Lipase PS on PDE-M540 was compared to a commercially available immobilized Lipase PS biocatalyst (Lipobond Lipase PS) and also applied in a packed-bed enzyme reactor operated in continuous-flow mode, where the optimal temperature of M540-PDE-PS reached the 70 °C, while the optimum for Lipobond Lipase PS was 50 °C.

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Vegetative propagation, chemical composition and antioxidant activity of yerba mate genotypes

Plant Genetic Resources ◽

10.1017/s1479262121000150 ◽

2021 ◽

pp. 1-10

Author(s):

Leandro Marcolino Vieira ◽

Renata de Almeida Maggioni ◽

Jéssica de Cássia Tomasi ◽

Erik Nunes Gomes ◽

Ivar Wendling ◽

...

Keyword(s):

Antioxidant Activity ◽

Phenolic Compounds ◽

Vegetative Propagation ◽

Adventitious Rooting ◽

Ilex Paraguariensis ◽

Total Phenolic ◽

Yerba Mate ◽

Total Phenolic Compounds ◽

Leaf Retention ◽

Correlated Components

Abstract Ilex paraguariensis, commonly known as yerba mate, is a tree species native to South America. Its commercial value is due to the manufacturing of teas, with potential also in the pharmacological and cosmetic industries. Vegetative propagation of yerba mate is considered an innovation to the traditional production systems based on sexual propagation. The present study aimed to evaluate the rhizogenic potential and chemical attributes of mini-cuttings from 15 yerba mate genotypes, as well as to verify the correlation between phytochemical and rooting-related variables. Mini-cuttings were collected from a pre-existing mini-clonal hedge and the experimental design was completely randomized, with 15 treatments (genotypes), four replications and 10 mini-cuttings per plot. After 120 days, mini-cuttings were assessed regarding rooting, mortality, callogenesis and leaf retention percentages, percentage of mini-cuttings with both calluses and roots, number of roots and average root length. At the time of collection, subsamples from each plot were used for phytochemical analyses including total phenolic compounds, protein, caffeine and theobromine contents and antioxidant activity. Rooting percentages ranged from 5 to 72.5%, with significant variation among genotypes. Adventitious rooting and phytochemical profile of yerba mate mini-cuttings are genotype-dependent. Leaf retention is a relevant factor in the rooting of yerba mate mini-cuttings and the levels of total phenolic compounds, antioxidants and theobromine present in mini-cuttings are negatively correlated components to Ilex paraguariensis adventitious rooting.

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PERSISTÊNCIA NO SOLO DE INÓCULO DE Beauveria bassiana EMPREGADO PARA O CONTROLE DE Hedypathes betulinus EM PLANTIO DE Ilex paraguariensis

FLORESTA ◽

10.5380/rf.v41i1.21194 ◽

2011 ◽

Vol 41 (1) ◽

Author(s):

Larissa Rolim Borges ◽

Sônia Maria Noemberg Lazzari ◽

Ida Chapaval Pimentel ◽

Lívia Cardoso Bueno de Camargo ◽

Lílian Mattos Kalinoski

Keyword(s):

Beauveria Bassiana ◽

Entomopathogenic Fungus ◽

Abiotic Factors ◽

Agricultural Practices ◽

Control Measures ◽

Ilex Paraguariensis ◽

Natural Occurrence ◽

Yerba Mate ◽

Santa Catarina ◽

Wood Borer

O controle da broca-da-erva-mate, Hedypathes betulinus, limita-se ao emprego de práticas silviculturais e catação manual dos insetos adultos, não sendo permitido o uso de inseticidas químicos na cultura. Esta pesquisa teve por objetivos verificar a presença natural de Beauveria bassiana no solo de plantio em monocultura de erva-mate, determinar a persistência de B. bassiana no solo após duas e três aplicações do fungo e averiguar a influência de fatores abióticos na estabilidade do fungo no solo. O estudo foi conduzido em um erval no município de Campo Alegre, Santa Catarina, Brasil, onde foram coletadas amostras de solo em duas áreas, para avaliação da presença natural de inóculos do fungo B. bassiana, procedendo-se à contagem, isolamento e identificação.Não foi detectada a ocorrência natural do fungo no solo em nenhuma das duas áreas. Após essa confirmação, foram realizadas pulverizações com B. bassiana em ambas as áreas, sendo que em uma ocorreram duas e na outra três aplicações. Após a última pulverização, realizada em fevereiro/2006, verificou-se que os inóculos do fungo persistiram por 90 dias na área com duas aplicações e 120 dias na área com três aplicações. A temperatura afetou a persistência do fungo no solo em ambas as áreas, mas a umidade relativa não mostrou influência sobre os inóculos em campo.Palavras-chave: Broca-da-erva-mate; controle biológico; epizootia; fungo entomopatogênico. AbstractPersistence in soil of inoculum of Beauveria bassiana used to control Hedypathes betulinus in yerba maté plantation, Ilex paraguariensis. Control measures of Hedypathes betulinus are restricted to agricultural practices and hand picking of adult insects. No chemical control is allowed in yerba maté cultivation areas. The objectives of this research were to verify the natural occurrence of the entomopathogenic fungus Beauveria bassiana in the soil of yerba maté in monoculture; to determine the persistence of inoculums in the soil after applications of the fungus; and to evaluate the influence of abiotic factors on fungus stability in the soil. The soil samples were taken from two experimental areas in a yerba maté plantation in the county of Campo Alegre, Santa Catarina, Brazil. The samples were analyzed in order to count, isolate and identify inoculums of B. bassiana and other fungi. After the confirmation that B. bassiana was not present in the soil, a suspension of the fungus was applied, twice in one of the areas and three times in the other. After the last application in February/2006, the inoculum persisted for 90 and 120 days, in the area with two and three applications, respectively. The temperature affected the persistence of B. bassiana in soil; however, the relative humidity did not.Keywords: Biological control; epizooty; entomopathogenic fungus; wood borer.

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