Inferring mixed-culture growth from total biomass data in a wavelet approach

Ibarra-Junquera, Vrani; Escalante‐Minakata, Pilar; Murguı́a, J. S.; Rosu, H. C.

doi:10.1016/j.physa.2006.03.015

Cited by 5 publications

(11 citation statements)

References 16 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Wavelet transform spectral analysis is a valuable approach in evaluating spatial and temporal patterns in ecology, and was proven successful in deriving the relative contributions of bacterial species-specific metabolism from continuous measurements of Eh (Bradshaw and Spies, 1992 ; Ibarra-Junquera et al, 2006 ; Escalante-Minakata et al, 2009 ). Temporal Eh measurements in this study were analyzed following a continuous Morlet wavelet transformation sensu Bradshaw and Spies ( 1992 ).…”

Section: Methodsmentioning

confidence: 99%

“…However, increasing evidence suggests that continuous measurements of redox potential (Eh) are valuable for tracking bacterial metabolic activities in time in laboratory microcosms (e.g. Ibarra-Junquera et al, 2006 ; Rabaey et al, 2007 ; Escalante-Minakata et al, 2009 ; Hunting and van der Geest, 2011 ). Bacterial membrane-bound and extracellular compounds create species specific, redox mediator dependent conditions at the surface of redox electrodes, which are visible as species specific continuous Eh measurements (Brasca et al, 2007 ; Reichart et al, 2007 ; Michelon et al, 2010 ; Tachon et al, 2010 ; Hunting and Kampfraath, 2013 ).…”

Section: Introductionmentioning

confidence: 99%

“…Bacterial membrane-bound and extracellular compounds create species specific, redox mediator dependent conditions at the surface of redox electrodes, which are visible as species specific continuous Eh measurements (Brasca et al, 2007 ; Reichart et al, 2007 ; Michelon et al, 2010 ; Tachon et al, 2010 ; Hunting and Kampfraath, 2013 ). Mixed bacterial communities generate a composite redox potential and Eh measurements have been shown to reflect relative metabolic activities of members of the community (Peiffer et al, 1992 ; Ibarra-Junquera et al, 2006 ; Escalante-Minakata et al, 2009 ). Continuous measurements of Eh under controlled laboratory conditions could thus provide the unique opportunity to monitor for the first time the effect of increasing bacterial community complexity toward an overlap in resource niches on the temporal changes in bacterial community metabolism in aquatic sediments.…”

Section: Introductionmentioning

confidence: 99%

See 2 more Smart Citations

Resource niche overlap promotes stability of bacterial community metabolism in experimental microcosms

et al. 2015

View full text Add to dashboard Cite

Decomposition of organic matter is an important ecosystem process governed in part by bacteria. The process of decomposition is expected to benefit from interspecific bacterial interactions such as resource partitioning and facilitation. However, the relative importance of resource niche breadth (metabolic diversity) and resource niche overlap (functional redundancy) on decomposition and the temporal stability of ecosystem processes received little scientific attention. Therefore, this study aims to evaluate the effect of an increase in bacterial community resemblance on both decomposition and the stability of bacterial metabolism in aquatic sediments. To this end, we performed laboratory microcosm experiments in which we examined the influence of bacterial consortia differing in number and composition of species on bacterial activity (Electron Transport System Activity, ETSA), dissolved organic carbon production and wavelet transformed measurements of redox potential (Eh). Single substrate affinities of the individual bacterial species were determined in order to calculate the metabolic diversity of the microbial community. Results presented here indicate that bacterial activity and organic matter decomposition increase with widening of the resource niche breadth, and that metabolic stability increases with increasing overlap in bacterial resource niches, hinting that resource niche overlap can promote the stability of bacterial community metabolism.

show abstract

Section: Methodsmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Resource niche overlap promotes stability of bacterial community metabolism in experimental microcosms

et al. 2015

View full text Add to dashboard Cite

show abstract

“…One can notice that we can determine a range of scales where the HE is the same up to the first decimal digit independently of the number of vanishing moments of the used wavelet. In the case of the first crossing, HE is constant only over two log scales (5)(6), whereas for the second crossing it stays constant over three log scales (3)(4)(5) Table 1: The Hölder exponents obtained in two different ranges of scales R1 and R2 for the first (subindex f ) and the second (subindex s) crossing singularities, respectively, with the wavelet functions corresponding to the second (G2), third (G3) and fourth (G4) derivatives of the Gaussian function.…”

Section: A Case Study: Two Haldane and One Monod Speciesmentioning

confidence: 98%

“…We will display results presenting the same total biomass signal analyzed with wavelets of the Gaussian family for different vanishing moments, from two to four. In addition, as in our previous work [3], we use the wavelet transform modulus maxima procedure introduced by Mallat and Hwang [2] that provides a precise location of the singularity and a clear cut measure of its Hölder exponent (HE) from the scaling of the wavelet transforms along the so-called modulus maxima lines on which the transforms reach local maxima with respect to the position coordinate. For more details, the reader is directed to the works [2] and [3].…”

Section: Wavelet Analysismentioning

confidence: 99%

Detection of mixed-culture growth in the total biomass data by wavelet transforms

Rosu

Murguı́a

Ibarra-Junquera

2010

JART

Self Cite

View full text Add to dashboard Cite

We have shown elsewhere that the presence of mixed-culture growth of microbial species in fermentation processes can be detected with high accuracy by employing the wavelet transform. This is achieved because the crosses in the different growth processes contributing to the total biomass signal appear as singularities that are very well evidenced through their singularity cones in the wavelet transform. However, we used very simple two-species cases. In this work, we extend the wavelet method to a more complicated illustrative fermentation case of three microbial species for which we employ several wavelets of different number of vanishing moments in order to eliminate possible numerical artifacts. Working in this way allows to filter in a more precise way the numerical values of the Hölder exponents. Therefore, we were able to determine the characteristic Hölder exponents for the corresponding crossing singularities of the microbial growth processes and their stability logarithmic scale ranges up to the first decimal in the value of the characteristic exponents. Since calibrating the mixed microbial growth by means of their Hölder exponents could have potential industrial applications, the dependence of the Hölder exponents on the kinetic and physical parameters of the growth models remains as a future experimental task.

show abstract

Online monitoring of Mezcal fermentation based on redox potential measurements

Escalante‐Minakata

Ibarra-Junquera

Rosu

et al. 2008

Bioprocess Biosyst Eng

Self Cite

View full text Add to dashboard Cite

We describe an algorithm for the continuous monitoring of the biomass and ethanol concentrations as well as the growth rate in the Mezcal fermentation process. The algorithm performs its task having available only the online measurements of the redox potential. The procedure combines an artificial neural network (ANN) that relates the redox potential to the ethanol and biomass concentrations with a nonlinear observer-based algorithm that uses the ANN biomass estimations to infer the growth rate of this fermentation process. The results show that the redox potential is a valuable indicator of the metabolic activity of the microorganisms during Mezcal fermentation. In addition, the estimated growth rate can be considered as a direct evidence of the presence of mixed culture growth in the process. Usually, mixtures of microorganisms could be intuitively clear in this kind of processes; however, the total biomass data do not provide definite evidence by themselves. In this paper, the detailed design of the software sensor as well as its experimental application is presented at the laboratory level.

show abstract

Inferring mixed-culture growth from total biomass data in a wavelet approach

Cited by 5 publications

References 16 publications

Resource niche overlap promotes stability of bacterial community metabolism in experimental microcosms

Resource niche overlap promotes stability of bacterial community metabolism in experimental microcosms

Detection of mixed-culture growth in the total biomass data by wavelet transforms

Online monitoring of Mezcal fermentation based on redox potential measurements

Contact Info

Product

Resources

About