scholarly journals Studies on the specificity of Candida rugosa lipase catalyzed esterification reactions in organic media

2006 ◽  
Vol 71 (1) ◽  
pp. 31-41 ◽  
Author(s):  
Dejan Bezbradica ◽  
Ivana Karalazic ◽  
Nevena Ognjanovic ◽  
Dusan Mijin ◽  
Slavica Siler-Marinkovic ◽  
...  
Keyword(s):  
Octanoic Acid ◽  
Candida Rugosa ◽  
Octadecenoic Acid ◽  
Decanoic Acid ◽  
Candida Rugosa Lipase ◽  
Reaction Rates ◽  
Initial Reaction ◽  
Octadecanoic Acid ◽  
Esterification Reactions ◽  
Commercial Lipase

In this study, the feasibility of the synthesis of various flavor esters catalyzed by a commercial lipase from Candida rugosa was investigated and the process parameters were optimized. Lipase from C. rugosa successfully catalyzed the synthesis of 19 esters. The highest yields, of more than 90 % after 20 h, were observed in the synthesis of short-chain esters, pentyl propanoate, isopentyl butanoate, and butyl butanoate. Increasing the number of carbon atoms of both substrates above 8 caused a significant decrease of the initial reaction rates and the final yields. The enzyme showed surprisingly low affinity towards pentanoic acid and hexanoic acid, compared with the higher homologues, octanoic acid and decanoic acid. In addition to the number of carbon atoms, the structure of the substrates had a significant influence on the enzyme activity. Namely, the activity of the enzyme towards isopropanol was significantly lower compared with n-propanol. Additionally, cis-9-octadecenoic acid was a better substrate than octadecanoic acid, its saturated analogue.

Esterification reactions catalyzed by surfactant-coated Candida rugosa lipase in organic solvents

2002 ◽  
Vol 37 (11) ◽  
pp. 1229-1233 ◽  
Author(s):  
Jin-Chuan Wu ◽  
Bao-Dong Song ◽  
Ai-Hua Xing ◽  
Y Hayashi ◽  
M.M.R Talukder ◽  
...  
Keyword(s):  
Organic Solvents ◽  
Candida Rugosa ◽  
Candida Rugosa Lipase ◽  
Esterification Reactions

scholarly journals Candida Rugosa Lipase Immobilized on Hydrophobic Support Accurel MP 1000 in the Synthesis of Emollient Esters

2021 ◽  
Author(s):  
Luiz Henrique Sales de Menezes ◽  
Eliezer Luz do Espírito Santo ◽  
Marta Maria Oliveira dos Santos ◽  
Iasnaia Maria de Carvalho Tavares ◽  
Adriano Aguiar Mendes ◽  
...  
Keyword(s):  
Specific Activity ◽  
Physical Adsorption ◽  
Candida Rugosa ◽  
Candida Rugosa Lipase ◽  
Wax Esters ◽  
Molar Ratio ◽  
Original Activity ◽  
The Stability ◽  
Esterification Reactions ◽  
Reaction Cycles

Abstract In the present work, Candida rugosa lipase (CRL) was immobilized by physical adsorption in organic medium on Accurel MP 1000 (AMP) with a protein load of 6.5 mg g-1 (mg protein/g support). CRL-AMP was applied with 5 and 10% of catalyst/volume of medium (m v-1) in esterification reactions of stearic acid with lauryl and cetyl alcohols producing the wax esters such as dodecanoyl octadecanoate 1 and hexadecanoyl octadecanoate 2 in a heptane medium. Six reaction cycles were studied to evaluate the stability and recyclability of the prepared biocatalyst. The specific activity (Asp) for CRL-AMP was 200 ± 20 U mg-1. Its catalytic activity was 1300 ± 100 U g-1. CRL-AMP was used in the synthesis of esters in heptane medium with a 1:1 acid:alcohol molar ratio at 45°C and 200 rpm. In synthesis 1, conversion was 62.5 ± 3.9% in 30 min at 10% m v-1 and 56.9 ± 2.8% in 54 min at 5% m v-1, while in synthesis 2, conversion was 79.0 ± 3.9% in 24 min at 10% m v-1, and 46.0 ± 2.4% in 54 min at 5% m v-1. Reuse tests after 6 consecutive cycles of reaction showed that the biocatalyst retained approximately 50% of its original activity for both reaction systems. CRL-AMP showed a high potential in the production of wax esters, since it started from low enzymatic load and high specific activities and conversions were obtained, in addition to allowing an increase in stability and recyclability of the prepared biocatalyst.

Reduction of citrinin biosynthesis by fatty acids in Monascus fermented food

2012 ◽  
Vol 5 (2) ◽  
pp. 163-167
Author(s):  
B.P. Panda ◽  
M. Ali
Keyword(s):  
Fatty Acids ◽  
Oleic Acid ◽  
Octanoic Acid ◽  
Decanoic Acid ◽  
Fermentation Medium ◽  
Fermented Food ◽  
Hexanoic Acid ◽  
Red Yeast Rice ◽  
Octadecanoic Acid ◽  
Rice Medium

Monascus-fermented food (red yeast rice, red mould rice, angkak) contains various useful secondary metabolites, for example lovastatin, along with citrinin, a hepatonephrotoxic agent. Fatty acids such as octanoic acid, oleic acid, octadecanoic acid, decanoic acid, hexanoic acid at increasing concentrations concentrations (0.1, 0.5, 1, 3 and 5%) were incorporated in solid fermentation medium to influence the citrinin level in red mould rice. Out of all the fatty acids tested, oleic acid and octadecanoic acid were ineffective, hexanoic acid and octanoic acid were moderately effective, whereas decanoic acid was highly effective in controlling citrinin biosynthesis. On the eleventh day of solid-state fermentation in red mould rice medium supplemented with 5% decanoic acid, citrinin concentration was 28 ng/g (lower than the advisory citrinin limit of 200 ng/g), whereas lovastatin concentration was 1.574 mg/g. Fermentation of rice medium supplemented with decanoic acid could produce a safer Monascus-based functional food than the non-supplemented medium.

Chemical composition of Azadirachta indica A. Juss and Ricinus communis Linn. seed oils growing in Marigat, Baringo County, Kenya

2020 ◽  
Vol 1 (2) ◽  
Author(s):  
Ann Kiplagat Jepkorir ◽  
Charles Maina Irungu ◽  
Philip Bett Kendagor
Keyword(s):  
Chemical Composition ◽  
Ricinoleic Acid ◽  
Unsaturated Fatty Acids ◽  
Ricinus Communis ◽  
Methyl Esters ◽  
Octadecenoic Acid ◽  
Seed Oils ◽  
Octadecanoic Acid ◽  
Alkyd Resins ◽  
Natural Remedies

All parts of A. indica (neem) and R. communis (castor) plants have mostly been used as natural remedies in the control and treatment of several ailments, control of pests and insects, animal feeds and production of industrial products globally. The seed oils of A. indica and R. communis are known to have antidiabetic, anti-helminthic, antifertility, antioxidant, antibacterial, anti-inflammatory, anti-cancer, insecticidal and mosquitocidal activity. This study reports for the first time the chemical composition of A. indica and R. communis seed oils from Marigat, Baringo County, Kenya. Seed oils of A. indica and R. communis were   extracted from mature dried seeds through cold pressing and boiling respectively and chemical composition determined using Gas Chromatography (GC)-Mass Spectrometry (MS).  The constituents of both seed oils were dominated by saturated and unsaturated fatty acids, cyclic esters and methyl esters. The predominant constituents of R. communis were (Z)-6-Octadecenoic acid (37.33%), Ricinoleic acid (30.22%) and 13-Hexyloxacyclotridec-10-en-2-one (26.67%) while those of A. indica were 2-hexyl-1-decanol (30.97%), Octadecanoic acid (29.69%) and Oxalic acid, 6-ethyloct-3-yl ethyl ester (15.55%). Oils contained Hexadecanoic acid and Octadecanoic acid which are used in the manufacture of several products such as candles, soaps, lotions, perfumes and cosmetics. Octadecenoic acid is important in control of human diseases and Ricinoleic acid in production of alkyd resins for surface coating and biofuel.  From the results, A. indica and R. communis seed oils constituents have potential in the agricultural, industrial, comestics and pharmaceutical sectors but require further fractionation to isolate the bioactive compounds.

Candida rugosa Lipase-Mediated Enantioselective Acetylation Studies on (.+-.)-3-Arylmethyl-3-hydroxymethyl-2,3-dihydro-1-benzopyran-4(H)-ones.

ChemInform ◽  
2005 ◽  
Vol 36 (23) ◽  
Author(s):  
Smriti Trikha ◽  
Rajesh Kumar ◽  
Ashish Dhawan ◽  
Poonam Poonam ◽  
Ashok K. Prasad ◽  
...  
Keyword(s):  
Candida Rugosa ◽  
Candida Rugosa Lipase

Ensemble Learning Approach with LASSO for Predicting Catalytic Reaction Rates

Synlett ◽  
2020 ◽  
Author(s):  
Akira Yada ◽  
Kazuhiko Sato ◽  
Tarojiro Matsumura ◽  
Yasunobu Ando ◽  
Kenji Nagata ◽  
...  
Keyword(s):  
Ensemble Learning ◽  
Reaction Rates ◽  
Initial Reaction Rate ◽  
Training Dataset ◽  
Initial Reaction ◽  
Learning Approach ◽  
Learning Framework ◽  
Machine Learning Approach ◽  
Reasonable Prediction ◽  
Epoxidation Of Alkenes

AbstractThe prediction of the initial reaction rate in the tungsten-catalyzed epoxidation of alkenes by using a machine learning approach is demonstrated. The ensemble learning framework used in this study consists of random sampling with replacement from the training dataset, the construction of several predictive models (weak learners), and the combination of their outputs. This approach enables us to obtain a reasonable prediction model that avoids the problem of overfitting, even when analyzing a small dataset.

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