Effect of food matrix type on growth characteristics and hemolysin production of Vibrio alginolyticus

Abstract Background: Vibrio alginolyticus is an important seafood-borne pathogen. There is increasing evidence that V.alginolyticus can also contaminate non-seafood by cross contamination and thereby cause food poisoning in humans. The growth and hemolysin production of V. alginolyticus at 30 °C in briny tilapia, shrimp, scallop, oyster, pork, chicken, freshwater fish and egg fried rice were investigated. Bacterial counts were enumerated by plate counting. Hemolysin production was evaluated by blood agar and hemolytic titer tests.Results: Based on the goodness of fit primary model statistics (R 2 , MSE, BF, AF), the modified Gompertz model was a better fit to V. alginolyticus growth in foods than the logistic model. Growth kinetic parameters of V. alginolyticus displayed a higher μ max and shorter λ in briny tilapia > shrimp > freshwater fish > egg fried rice > scallop > oyster > chicken > pork. It was notable that the V. alginolyticus counts were similar at the stationary phase, with no significant growth behavior difference between raw and cooked foods. However, higher thermostable direct hemolysin activity and hemolytic titer were observed in briny tilapia > egg fried rice > shrimp > freshwater fish > chicken > scallop > oyster > pork.Conclusion: V. alginolyticus growth was good in all food matrix types tested. Contrary to current belief, V. alginolyticus displayed a higher hemolytic activity in some non-seafoods (freshwater fish, egg fried rice and chicken) than in scallop or oyster. This is the first report of growth and toxicity of V. alginolyticus in different food matrices and confirmation that some non-seafood contaminated with V. alginolyticus can be even more pathogenic. This study will enhance the awareness of non-seafood safety and improve the V. alginolyticus risk assessment accuracy.

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Effect of food matrix type on growth characteristics and hemolysin production of Vibrio alginolyticus

10.21203/rs.3.rs-29965/v1 ◽

2020 ◽

Author(s):

Xiaojun Hu ◽

Rundong Wang ◽

Yijia Deng ◽

Qi Deng ◽

Zhijia Fang ◽

...

Keyword(s):

Freshwater Fish ◽

Goodness Of Fit ◽

Gompertz Model ◽

Food Matrix ◽

Microbial Risk Assessment ◽

Microbial Risk ◽

Primary Model ◽

Thermostable Direct Hemolysin ◽

Effect Of Food ◽

Modified Gompertz Model

Abstract Background: The growth and hemolysin production of V. alginolyticus at 30 °C in briny Tilapia , shrimp, scallop, oyster, pork, chicken, freshwater fish and egg fried rice were investigated. Bacterial counts were enumerated by plate counting. Hemolysin production was evaluated by blood agar and hemolytic titer tests. Results: Based on the goodness of fit primary model statistics (R 2 , MSE, BF, AF), the modified Gompertz model was a better fit to V. alginolyticus growth in foods than the logistic model. Growth kinetic parameters of V. alginolyticus displayed a higher μ max and shorter λ in briny Tilapia > shrimp > freshwater fish > egg fried rice > scallop > oyster > chicken > pork. It was notable that the V. alginolyticus counts were similar at the stationary phase, with no significant growth behavior difference between raw and cooked foods. However, higher thermostable direct hemolysin activity and hemolytic titer were observed in briny Tilapia > egg fried rice > shrimp > freshwater fish > chicken > scallop > oyster > pork. Conclusion: V. alginolyticus growth was good in all food matrix types tested. Contrary to current belief, V. alginolyticus displayed a higher hemolytic activity in some non-seafoods (freshwater fish, egg fried rice and chicken) than in scallop or oyster. This is the first report of growth and toxicity of V. alginolyticus in non-seafood. This finding will significantly improve the accuracy of microbial risk assessment of V. alginolyticus in different food matrices especially during warmer climatic periods when it is most prevalent.

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Effect of food matrix type on growth characteristics and hemolysin production of Vibrio alginolyticus

Journal of Food Protection ◽

10.4315/jfp-20-490 ◽

2021 ◽

Author(s):

Rundong Wang ◽

Xiaojun Hu ◽

Yijia Deng ◽

Ravi Gooneratne

Keyword(s):

Freshwater Fish ◽

Logistic Model ◽

Goodness Of Fit ◽

Gompertz Model ◽

Primary Model ◽

Current Belief ◽

Thermostable Direct Hemolysin ◽

Effect Of Food ◽

Similar Growth ◽

Modified Gompertz Model

The growth and hemolysin production of two V. alginolyticus strains (HY9901 and ATCC17749T) at 30 °C in briny tilapia, shrimp, scallop, oyster, pork, chicken, freshwater fish and egg fried rice were investigated. Bacterial counts were enumerated by plate counting. Hemolysin production was evaluated by blood agar and hemolytic titer tests. The two V. alginolyticus strains displayed similar growth and hemolysin production patterns in the foods. Based on the goodness of fit primary model statistics (R 2 , MSE, BF, AF), the modified Gompertz model was a better fit to V. alginolyticus growth in foods than the logistic model. Growth kinetic parameters of V. alginolyticus displayed a higher μ max and shorter λ in briny tilapia > shrimp > freshwater fish > egg fried rice > scallop > oyster > chicken > pork. It was notable that the V. alginolyticus counts were similar at the stationary phase, with no significant growth behavior difference between raw and cooked foods. Significantly higher (p < 0.05) thermostable direct hemolysin (TDH) activity was produced by V. alginolyticus in briny tilapia > freshwater fish > shrimp > chicken > egg fried rice > scallop > oyster > pork. But the hemolytic titer was not consistent with the TDH activity, being significantly higher (p < 0.05) in briny tilapia > egg fried rice > shrimp > freshwater fish > chicken > scallop > oyster > pork. Contrary to current belief, V. alginolyticus displayed a higher hemolysin production in some non-seafoods (freshwater fish, egg fried rice and chicken) than in scallop or oyster. This is the first report of growth and toxicity of V. alginolyticus in different food matrices and confirmation that some non-seafood contaminated with V. alginolyticus can be even more pathogenic. This study will enhance the awareness of non-seafood safety and improve the V. alginolyticus risk assessment accuracy.

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Batch Anaerobic Co-Digestion and Biochemical Methane Potential Analysis of Goat Manure and Food Waste

Energies ◽

10.3390/en14071952 ◽

2021 ◽

Vol 14 (7) ◽

pp. 1952

Author(s):

Ayobami Orangun ◽

Harjinder Kaur ◽

Raghava R. Kommalapati

Keyword(s):

Food Waste ◽

Gompertz Model ◽

Water Displacement ◽

Biochemical Methane Potential ◽

Greenhouse Gasses ◽

Nonlinear Regression Models ◽

The Us ◽

Methane Potential ◽

Goat Manure ◽

Modified Gompertz Model

The improper management of goat manure from concentrated goat feeding operations and food waste leads to the emission of greenhouse gasses and water pollution in the US. The wastes were collected from the International Goat Research Center and a dining facility at Prairie View A&M University. The biochemical methane potential of these two substrates in mono and co-digestion at varied proportions was determined in triplicates and processes were evaluated using two nonlinear regression models. The experiments were conducted at 36 ± 1 °C with an inoculum to substrate ratio of 2.0. The biomethane was measured by water displacement method (pH 10:30), absorbing carbon dioxide. The cumulative yields in goat manure and food waste mono-digestions were 169.7 and 206.0 mL/gVS, respectively. Among co-digestion, 60% goat manure achieved the highest biomethane yields of 380.5 mL/gVS. The biodegradabilities of 33.5 and 65.7% were observed in goat manure and food waste mono-digestions, while 97.4% were observed in the co-digestion having 60% goat manure. The modified Gompertz model is an excellent fit in simulating the anaerobic digestion of food waste and goat manure substrates. These findings provide useful insights into the co-digestion of these substrates.

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A generalized Gompertz growth model with applications and related birth-death processes

Ricerche di Matematica ◽

10.1007/s11587-020-00548-y ◽

2020 ◽

Author(s):

Majid Asadi ◽

Antonio Di Crescenzo ◽

Farkhondeh A. Sajadi ◽

Serena Spina

Keyword(s):

Growth Model ◽

Growth Curve ◽

Goodness Of Fit ◽

Gompertz Model ◽

Death Process ◽

Birth Process ◽

Failure Data ◽

First Case ◽

Gompertz Growth Model ◽

Birth Death

AbstractIn this paper, we propose a flexible growth model that constitutes a suitable generalization of the well-known Gompertz model. We perform an analysis of various features of interest, including a sensitivity analysis of the initial value and the three parameters of the model. We show that the considered model provides a good fit to some real datasets concerning the growth of the number of individuals infected during the COVID-19 outbreak, and software failure data. The goodness of fit is established on the ground of the ISRP metric and the $$d_2$$ d 2 -distance. We also analyze two time-inhomogeneous stochastic processes, namely a birth-death process and a birth process, whose means are equal to the proposed growth curve. In the first case we obtain the probability of ultimate extinction, being 0 an absorbing endpoint. We also deal with a threshold crossing problem both for the proposed growth curve and the corresponding birth process. A simulation procedure for the latter process is also exploited.

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Optimizing anaerobic co-digestion of goat manure and cotton gin trash using biochemical methane potential (BMP) test and mathematical modeling

SN Applied Sciences ◽

10.1007/s42452-021-04706-1 ◽

2021 ◽

Vol 3 (8) ◽

Author(s):

Harjinder Kaur ◽

Raghava R. Kommalapati

Keyword(s):

Liquid Fraction ◽

Gompertz Model ◽

Biochemical Methane Potential ◽

Methane Potential ◽

Mathematical Equations ◽

Goat Manure ◽

Bmp Test ◽

Batch Bioreactors ◽

Modified Gompertz Model ◽

Cotton Gin

AbstractAnaerobic co-digestion is widely adopted to enhance process efficacy by balancing the C/N ratio of the feedstock while converting organic wastes to biomethane. Goat manure (GM) and cotton gin trash (CGT) were anaerobically co-digested in triplicate batch bioreactors. The process was optimized and evaluated utilizing mathematical equations. The liquid fraction of the digestate was analyzed for nitrate and phosphate. The co-digestions with 10 and 20% CGT having the C/N ratios of 17.7 and 19.8 yielded the highest and statistically similar 261.4 ± 4.8 and 262.6 ± 4.2 mL/gvs biomethane, respectively. The biodegradability (BD) of GM and CGT was 94.5 ± 2.7 and 37.6 ± 0.8%, respectively. The BD decreased proportionally with an increase in CGT percentage. The co-digestion having 10% CGT yielded 80–90% of biomethane in 26–39 d. The modified Gompertz model-predicted and experimental biomethane values were similar. The highest synergistic effect index of 15.6 ± 4.7% was observed in GM/CGT; 30:70 co-digestion. The concentration of nitrate and phosphate was lower in the liquid fraction of digestate than the feedstocks, indicating that these nutrients stay in the solid fraction. The results provide important insights in agro-waste management, further studies determining the effects of effluent application on plants need to be conducted.

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Prediction of growth kinetics of Pseudomonas spp. in meat products under isothermal and non-isothermal storage conditions

Food and Health ◽

10.3153/fh21021 ◽

2021 ◽

Vol 7 (3) ◽

pp. 194-202

Author(s):

Fatih Tarlak

Keyword(s):

Goodness Of Fit ◽

Storage Temperature ◽

Food Products ◽

Storage Conditions ◽

Chicken Meat ◽

Lag Phase ◽

Phase Duration ◽

Pseudomonas Spp ◽

Primary Model ◽

One Step

The main objective of the present study was to develop and validate a new alternative modelling method to predict the shelf-life of food products under non-isothermal storage conditions. The bacterial growth data of the Pseudomonas spp. was extracted from published studies conducted for aerobically-stored fish, pork and chicken meat and described with two-step and one-step modelling approaches employing different primary models (the modified Gompertz, logistic, Baranyi and Huang models) under isothermal storage temperatures. Temperature dependent kinetic parameters (maximum specific growth rate ‘µmax’ and lag phase duration ‘λ’) were described as a function of storage temperature via the Ratkowsky model integrated with each primary model. The Huang model based on the one-step modelling approach yielded the best goodness of fit results (RMSE = 0.451 and adjusted-R2 = 0.942) for all food products at isothermal storage conditions, therefore, was also used to check it’s the prediction capability under non-isothermal storage conditions. The differential form of the Huang model provided satisfactorily statistical indexes (1.075 > Bf > 1.014 and 1.080 > Af > 1.047) indicating reliably being able to use to describe the growth behaviour of Pseudomonas spp. in fish, pork and chicken meat subjected to non-isothermal storage conditions.

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Theoretical and Experimental Results on the Recovery of Potato Processing Residuals by Anaerobic Digestion

Revista de Chimie ◽

10.37358/rc.19.7.7373 ◽

2019 ◽

Vol 70 (7) ◽

pp. 2524-2529 ◽

Cited By ~ 2

Author(s):

Andreea D. Dima ◽

Carmen Mateescu ◽

Oana C. Parvulescu ◽

Eduard M. Lungulescu ◽

Nicoleta O. Nicula

Keyword(s):

Anaerobic Digestion ◽

Gompertz Model ◽

Economic Feasibility ◽

Potato Processing ◽

Biomethane Potential ◽

Potato Waste ◽

Cone Model ◽

Treatment Technologies ◽

Negative Environmental Impact ◽

Modified Gompertz Model

Anaerobic digestion of organic matter with high moisture content has proven to be a suitable method for disposal of wet organic residuals with several advantages compared to other treatment technologies. This paper aimed at evaluating the theoretical and experimental biomethane potential of food processing residuals that are responsible for negative environmental impact, with exemplification for the potato processing waste. The biomethane potential is a useful parameter to assess the economic efficiency of anaerobic digestion processes as it can considerably influence the efficiency and the economic feasibility of the energy recovery technologies. Both experimental and theoretical biomethane potentials of potato waste in mesophilic anaerobic digestion as well as biodegradability of the substrate were estimated. Moreover, effects of microalgal extract addition on the digestion of potato waste were examined in an attempt to stimulate the anaerobic digestion. Cone model and a modified Gompertz model were used to predict the dynamics of biomethane production.

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Longitudinal Pattern of Aerenchyma Formation Using the Ti-Gompertz Model in Rice Adventitious Roots

Frontiers in Plant Science ◽

10.3389/fpls.2021.776971 ◽

2021 ◽

Vol 12 ◽

Author(s):

Yun Chen ◽

Guoming Li ◽

Buhong Zhao ◽

Yajun Zhang ◽

Kun Liu ◽

...

Keyword(s):

Adventitious Roots ◽

Goodness Of Fit ◽

Gompertz Model ◽

Root Apex ◽

Information Criterion ◽

Ordinary Least Squares ◽

Parameter Estimates ◽

Aerenchyma Formation ◽

Root Aerenchyma ◽

Longitudinal Pattern

The longitudinal pattern of root aerenchyma formation of its relationship with the function of adventitious roots in rice remains unclear. In this study, the percentage of the aerenchyma area to the cross-sectional area (i.e., aerenchyma percentage) was fit with four non-linear models, namely, W0-Gompertz, Ti-Gompertz, logistic, and von Bertalanffy. Goodness-of-fit criteria such as the R2, the Akaike information criterion (AIC), and the Bayesian information criterion (BIC) were used to select the model. The bias of the parameters was evaluated using the difference between the ordinary least squares-based parameter estimates and the mean of 1,000 bootstrap-based parameter estimates and the symmetry of the distributions of these parameters. The results showed that the Ti-Gompertz model, which had a high goodness-of-fit with an R2 close to 1, lower AIC and BIC values, parameter estimates close to being unbiased, and good linear approximation, provided the best fit for the longitude pattern of rice aerenchyma formation with different root lengths among the competing models. Using the second- and third-order derivatives according to the distance from the root apex, the critical points of Ti-Gompertz were calculated. The rapid stage for aerenchyma formation was from the maximum acceleration point (1.38–1.76 cm from the root apex) to the maximum deceleration point (3.13–4.19 cm from the root apex). In this stage, the aerenchyma percentage increased by 5.3–15.7% per cm, suggesting that the cortical cells tended to die rapidly for the aerenchyma formation rather than for the respiration cost during this stage. Meanwhile, the volume of the aerenchyma of the entire roots could be computed using the integral function of the Ti-Gompertz model. We proposed that the longitudinal pattern of root aerenchyma formation modeled by the Ti-Gompertz model helped to deeply understand the relationship between the anatomical traits and physiological function in rice adventitious roots.

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