34 research outputs found
Mathematical Model of \u3cem\u3eChlorella minutissima\u3c/em\u3e UTEX2341 Growth and Lipid Production Under Photoheterotrophic Fermentation Conditions
To reduce the cost of algal biomass production, mathematical model was developed for the first time to describe microalgae growth, lipid production and glycerin consumption under photoheterotrophic conditions based on logistic, LuedekingâPiret and LuedekingâPiret-like equations. All experiments were conducted in a 2 L batch reactor without considering CO2 effect on algaeâs growth and lipid production. Biomass and lipid production increased with glycerin as carbon source and were well described by the logistic and LuedekingâPiret equations respectively. Model predictions were in satisfactory agreement with measured data and the mode of lipid production was growth-associated. Sensitivity analysis was applied to examine the effects of certain important parameters on model performance. Results showed that S0, the initial concentration of glycerin, was the most significant factor for algae growth and lipid production. This model is applicable for prediction of other single cell algal species but model testing is recommended before scaling up the fermentation of process
Anammox Process: the Principle, the Technological Development and Recent Industrial Applications
The ANAerobic AMMonium OXidation or Anammox process, nowadays becomes an important technology for industrial wastewater treatment plants, especially for an effective denitrification process. Anammox process has been widely known for its high efficiency in nitrogen removal in various kinds of wastewater. This review described the details of Anammox process, including biochemical characteristics, technical development, and its applications based on literature studies. Additionally, applications of Anammox process in wastewater treatment in different types of bioreactors were discussed. Finally, three typical applications of Anammox process in nitrogen removal for landfill leachate, fertilizer residues from agricultural activities and petrochemical industrial wastewater treatment were analyzed
A Potential of Mutant Yeast Strain for Improvement Arabica Coffee Fermentation Process
Arabica coffee is a worldwide popular beverage. Coffee fermentation is important process to enhance the coffee flavor quality. Microorganisms involved in the process are the main factor affecting coffee quality. This study aims to apply the new starter culture of Wickerhamomyces anomalus UV22-3, a UV mutant strain, for coffee fermentation and to improve arabica coffee beverage quality. The results showed that W. anomalus UV22-3 as a starter culture for coffee fermentation could enhance the coffee flavor quality compared to the control experiment (without inoculum). Fermented arabica coffee by strain UV22-3 showed a higher cupping score than wild type and a control condition with unique cupping notes. According to the flavor profile evaluated by Q-graders, the result of this sensory evaluation is 82. Microbial population in the fermentation broth was evaluated. The total yeast number was stable, while the total bacteria was higher after 24 h of strain UV22-3 fermentation. The pH value slightly decreased when the total dissolved solid increased. This research is one alternative to improve the quality of coffee in Thailand by using a novel yeast strain
Process Optimization of Deep Eutectic Solvent Pretreatment of Coffee Husk Biomass
The increased processing of coffee beans has generated huge amount of coffee husk, which are improperly disposed. Inappropriate disposal of coffee husk has led to release of toxic compounds to the environment causing serious environmental concerns. To mitigate the impact of improperly disposed coffee husk, it is suggested for valorisation of the coffee husk. Hence, this study has focussed on identifying the potential of coffee husk in maximizing the sugar yield from it which can be converted to value added product. Deep eutectic solvent (DES) involving choline chloride and lactic acid (ChCl:LA) mixed at 1:4 molar ratio was studied to investigate the effect of DES pretreatment on coffee husk to produce reducing sugar in the hydrolysis process. Pretreatment conditions of the biomass were optimized for biomass loading (5-20%, w/w), temperature (70-120 °C), and duration (60-240 min) using Response Surface Methodology (RSM) for obtaining maximum yield of reducing sugar. The RSM model predicted an optimal pretreatment condition of biomass loading with 20% (w/w), pretreated at 120 °C for 231.80 min to achieve maximum sugar yield (30.522%). The pretreatment effect on biomass composition was analyzed using the Van Soest method, which showed an increase in the cellulose content along with the hemicellulose removal when compared with the native biomass. Moreover, evaluation of chemical structural changes also confirmed the effectiveness of DES pretreatment. Thus, the current study would illustrate the potential of coffee husk to produce value-added compounds from it
Development of Virtual Pulse Simulation for Pulse Diagnosis Studies
Pulse signals can be used to observe the early sign of patients' health problems. From medical researches, monitoring the characteristic of arterial pulse waveform shows some risk indicator of specific diseases, e.g., hypertension, cardiovascular and heart failure diseases. A simple way to get arterial pulse wave is by using fingers to touch the radial artery position on the wrist. In the traditional Chinese medicine, a physician can use the information of arterial pulse wave-form to identify diseases based on the physicianâs ability and experience. The improvement of the skill in pulse measurement can be improved by training using various kinds of pulses that represent each disease. This paper proposes a development of the virtual pulse simulation using Augmented Reality (AR) and haptic device for pulse diagnosis studies under various situations. The pulse simulation generates arterial pulse waveforms based on Sine and Gaussian functions. In this study, the mathematical model can generate the pulse wave like human pulse by setting up specific parameters. We can generate pulse waveform which representing different kinds and states of diseases by varying the mathematical model and parameters such as pulse rate or pulse pressure. The features of this work include how to generate force feedback from the mathematical models using the haptic device and how the virtual 3D can display visual feedback. The pulse simulation is useful for the health sciences students, especially the nursing students in training to identify some diseases. The evaluation of the system was carried out by first-year nursing students regarding usability, satisfaction, and performance
Study of Mathematical Models in Hot Air Drying of Herbs in Herbal Compress Ball
Herbal compress ball is currently one of important products of Thailand for exporting sales worldwide. It is used in Thai traditional medical treatment and spa to reduce muscle pain and relaxation. This research aimed to generate the mathematical models representing the behaviors of herbs in hot air drying to extend shelf life for exporting sales. Here, six types of herbs, including Prai (Zingiber cassumunar Roxb.), Turmeric (Curcuma longa Linn.), Lemongrass (Cymbopogon citratus), Kaffir lime (Citrus hystrix), Soap Pod leaves (Acacia concinna) and Tamarind Leaves (Tamarindus indica Linn.) were dried in different temperature at 60, 70, and 80 °C. Fours drying models, Page, Henderson and Pabis, and Logarithmic and Fick's second law equation were applied with experimental data of drying herbs to predict the rate of diffusion of water. The results showed that the Page model is the most suitable model due to the highest decision coefficient (R2) but the lowest Root Mean Square Error (RMSE). The effective moisture diffusivity (Deff) of the herbs in herbal compress ball was increased with increased the drying temperature. The size of the herb particle translated inversely with effective moisture diffusivity (Deff) value
Chemical Profiling Analysis and Identification the Bioactivities of Herbal Compress Extracts
The traditional Thai herbal compress is composed of six different types of herbs including Ginger (Zingiber cassumunar), Turmeric (Curcuma longa Linn.), Soap Pod (Acacia concinna), Kaffir lime (Citrus hystrix), Lemongrass (Cymbopogon citratus), and Tamarind (Tamarindus indica Linn.). Herbal compress is used in treatment of Thai traditional massage to relieve the body pain and muscle strains. The objective of this work is to perform chemical profiling and extraction modelling of herbal compress obtained from solvent extraction method. The kinetic models, The second order and Fickâs second law, representing the extraction behaviors of bioactive compounds were constructed to fit with experimental data of solvent extraction. Under tested condition, the extraction equilibrium was reached after 360 min and the second-order model gives the best fit for the experimental data with high coefficients of correlation (R2 = 0.9927). Additionally, chemical profiling analysis showed that the amounts and variations of bioactive components in drying-pretreated herbal compress were more abundant than that of untreated sample. This finding could be applied further for preparation and production of traditional Thai herbal compress in the industrial scale
Itaconic Acid: A Promising and Sustainable Platform Chemical?
Due to the increasing demand and focus for sustainable chemicals and fuels that are independent from fossil resources, itaconic acid gained interest and recognized for market position as a potential bio-based platform chemical. Itaconic acid can be produced via a chemical pathway or a biotechnological pathway, the more effective production way is the latter one, which is currently conducted in industrial scale production. In order to replace fossil-based chemicals, the efficiency of the current production that is mainly operated by using Aspergillus terreus has to be improved to achieve the economically feasible process. The recent progress in understanding the biosynthesis pathway, finding new raw materials and microbes as well as applying a more effective downstream process, facilitated the optimization of existing processes and resulted in reduction of production cost. However, there is still need for further optimization to achieve higher final concentrations and to use a broader range of low cost sustainable raw materials. Nowadays, the largest industrial producers of itaconic acid are located in China and the USA. If the production costs can be reduced and the downstream value chain for itaconic acid can be expanded, the market could be grow in the future
Effect of Cellulase-producing Microbial Consortium on Biogas Production from Lignocellulosic Biomass
Evaluation of a Community-Based Diabetes Prevention Program in Thailand: A Cluster Randomized Controlled Trial
Objectives: Lifestyle interventions have been shown to effectively reduce the incidence of diabetes, but evidence from middle-income countries is scarce. We evaluated the effectiveness of a lifestyle program to prevent diabetes in primary-care settings in Thailand. Methods: A matched-pair cluster randomized controlled trial was conducted in 68 primary care units in 8 provinces. The primary care units were randomly assigned to intervention or control arms. Individuals aged 30 to 65 years with impaired oral glucose tolerance were recruited and followed up for 2 years. The intervention included periodic group-based activities on healthy lifestyle behaviors; the control group received a one-time education program. The primary outcome was the incidence rate of type 2 diabetes at 24 months after the intervention. Results: A total of 1903 individuals participated (873 in the control group and 1030 in the intervention group). At baseline, participantsâ characteristics did not differ between groups. After 24 months, the incidence rates (per 100 person-year) of diabetes was 12.1% (95% CI 10.7% to 13.8%) in the intervention group, and 16.6% (95% CI 14.6 to 18.8%) in the control group ( P < .001). Overall, the adjusted hazard ratio for diabetes incidence was 0.72 (95% CI 0.60 to 0.86). A mean body weight reduction of 1.5 kg was observed in the intervention group, whereas, an increase of 0.4 kg was observed in the control group ( P < .001). Conclusion: A community-based lifestyle modification through participatory group activities can prevent or delay the incidence of diabetes among Thai populations with impaired glucose tolerance