Parallel factor analysis combined with PLS regression applied to the on-line monitoring of Pichia pastoris cultures

Surribas, Anna; Amigo, José Manuel; Coello, J.; Montesinos, José Luis González; Valero, Francisco; Maspoch, S.

doi:10.1007/s00216-006-0355-z

Cited by 31 publications

(22 citation statements)

References 23 publications

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“…In such cases, multivariate chemometric techniques can be used to analyze the whole spectra. Principal components analysis (PCA) is normally employed to compress noisy and correlated data sets with minimal loss of information (Boehl et al, 2003;Surribas et al, 2006a;Haack et al, 2007;Rhee and Kang, 2007;Wolf et al, 2007). Partial least squares (PLS) regression appears to be the most popular chemometric method for calibrating 2D fluorescence maps with off-line bioprocess variables such as biomass, substrates and products of interest (Boehl et al, 2003;Lantz et al, 2006;Surribas et al, 2006b;Haack et al, 2007;Rhee and Kang, 2007).…”

Section: Introductionmentioning

confidence: 99%

In situ 2D fluorometry and chemometric monitoring of mammalian cell cultures

Teixeira

Portugal

Carinhas

et al. 2008

Biotech & Bioengineering

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The main objective of the present study was to investigate the use of in situ 2D fluorometry for monitoring key bioprocess variables in mammalian cell cultures, namely the concentration of viable cells and the concentration of recombinant proteins. All studies were conducted using a recombinant Baby Hamster Kidney (BHK) cell line expressing a fusion glycoprotein IgG1-IL2 cultured in batch and fed-batch modes. It was observed that the intensity of fluorescence signals in the excitation/emission wavelength range of amino acids, vitamins and NAD(P)H changed along culture time, although the dynamics of single fluorophors could not be correlated with the dynamics of the target state variables. Therefore, multivariate chemometric modeling was adopted as a calibration methodology. 2D fluorometry produced large volumes of redundant spectral data, which were first filtered by principal components analysis (PCA). Then, a partial least squares (PLS) regression was applied to correlate the reduced fluorescence maps with the target state variables. Two validation strategies were used to evaluate the predictive capacity of the developed PLS models. Accurate estimations of viable cells density (r(2) = 0.95; 99.2% of variance captured in the training set; r(2) = 0.91; 97.7% of variance captured in the validation set) and of glycoprotein concentration (r(2) = 0.99 and 99.7% of variance captured in the training set; r(2) = 0.99 and 99.3% of variance captured in the validation set) were obtained over a wide range of reactor operation conditions. The results presented herein confirm that 2D fluorometry constitutes a reliable methodology for on-line monitoring of viable cells and recombinant protein concentrations in mammalian cell cultures.

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Section: Introductionmentioning

confidence: 99%

In situ 2D fluorometry and chemometric monitoring of mammalian cell cultures

Teixeira

Portugal

Carinhas

et al. 2008

Biotech & Bioengineering

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“…To determine the number of components, various numerical characteristics of the model can be used e.g. explained variance (%) (Surribas et al, 2006) and core consistency (corcondia) (%) (Divya and Mishra, 2007) -ideally, both values are 100 %. The results of PARAFAC modelling are relative concentrations (score) and spectral profiles (loadings) of components in the samples (Bro 1997).…”

Section: Multivariate Analysismentioning

confidence: 99%

“…Excitation and emission profiles can be assigned to fluorophores by comparison with recorded spectra of standards or with data reported in literature. Score values can be used to construct the calibration model describing the relationship between the concentration of the fluorophore and the score value (Surribas et al, 2006). In this work, PLS−regression was used.…”

Section: Multivariate Analysismentioning

confidence: 99%

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Determination of adulterants in adulterant-fruit spirit blends using excitation-emission matrix fluorescence spectroscopy

Jakubíková

Sádecká

Májek

2015

Acta Chimica Slovaca

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This study introduces a reliable method to detect adulteration of spirit drinks. Excitation-emission matrix (EEM) fluorescence in combination with parallel factor analysis (PARAFAC) and partial least squares (PLS) regression was used to determine the content of water and ethanol in adulterated fruit spirit samples. EEM fluorescence spectra recorded in the emission wavelength range of 315-450 nm and in the excitation wavelength range of 240-305 nm were used for PARAFAC. The model created using PARAFAC-PLS was able to predict the water and ethanol level in adulterated apple spirit with the root mean square error of prediction (RMSEP) values of 1.9 % and 1.8 %, respectively. Regarding adulterated plum spirit, the RMSEP values of 0.7 % and 3.5 % were obtained for water and ethanol, respectively. The aim of this work was to determine whether EEM-PARAFAC can be used to distinguish between plum and apple spirit. Better results were obtained for apple spirit and the method is useful also for water-apple spirit blends.

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“…[20][21][22][23] However, this methodology was not employed to directly link the spectral resolution information to a biosynthetic pathway. Therefore, this is a new and complementary approach for the initial analysis of the biosynthesis of fluorescent natural products.…”

Section: Introductionmentioning

confidence: 99%

The violacein biosynthesis monitored by multi-wavelength fluorescence spectroscopy and by the PARAFAC method

Dantas¹,

Volpe²,

Durán³

et al. 2012

J. Braz. Chem. Soc.

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A obtenção de informações sobre uma rota biossintética é um procedimento complexo e trabalhoso. Neste sentido, o presente trabalho apresenta uma nova abordagem para a análise inicial da biossíntese de produtos naturais fluorescentes usando a biossíntese da violaceína como exemplo. Para tanto, uma cultura da Chromobacterium violaceum foi inoculada em um biorreator de onde alíquotas eram retiradas a cada 2 h para posterior análise por espectroscopia de fluorescência 2D. As matrizes de emissão-excitação obtidas demonstraram o comportamento dinâmico dos sinais de fluoróforos que são consumidos e produzidos pela bactéria. Estes sinais foram resolvidos pelo método PARAFAC (análise paralela de fatores) perfazendo um total de seis espécies químicas. O triptofano e a violaceína foram identificados por comparação espectral. A identificação dos outros fluoróforos mostrou-se a etapa crítica devido à falta de banco de dados de produtos naturais fluorescentes para comparação. Por fim, esta metodologia apresenta um grande potencial para fornecer informações da biossíntese de produtos naturais.Obtaining information about a biosynthetic pathway is a complex and laborious procedure. In this sense, this work presents a new approach for the initial analysis of the biosynthesis of fluorescent natural products using as example the violacein biosynthesis. For this, a culture of Chromobacterium violaceum was grown in a bioreactor from which aliquots were collected every 2 h for subsequent analysis by multi-wavelength fluorescence spectroscopy. The excitation-emission matrices demonstrated the dynamic behavior of the fluorophores signal that are consumed and produced by the bacterium. These signals were resolved by PARAFAC (parallel factor analysis) method totalizing six pure components. Tryptophan and violacein were identified by comparison to spectra available in the literature. The identification of other fluorophores was critical step due to the lack of a database of fluorescent natural products to compare spectra. Finally, this methodology has great potential to achieve a deeper insight into the biosynthesis of natural products.

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Parallel factor analysis combined with PLS regression applied to the on-line monitoring of Pichia pastoris cultures

Cited by 31 publications

References 23 publications

In situ 2D fluorometry and chemometric monitoring of mammalian cell cultures

In situ 2D fluorometry and chemometric monitoring of mammalian cell cultures

Determination of adulterants in adulterant-fruit spirit blends using excitation-emission matrix fluorescence spectroscopy

The violacein biosynthesis monitored by multi-wavelength fluorescence spectroscopy and by the PARAFAC method

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