30 research outputs found
Bacterial cellulose-lactoferrin as an antimicrobial edible packaging
Bacterial cellulose (BC) films from two distinct sources (obtained by static culture with Gluconacetobacter xylinus ATCC 53582 (BC1) and from a commercial source (BC2)) were modified by bovine lactoferrin (bLF) adsorption. The functionalized films (BC+bLF) were assessed as edible antimicrobial packaging, for use in direct contact with highly perishable foods, specifically fresh sausage as a model of meat products. BC+bLF films and sausage casings were characterized regarding their water vapour permeability (WVP), mechanical properties, and bactericidal efficiency against two food pathogens, Escherichia coli and Staphylococcus aureus. Considering their edibility, an in vitro gastrointestinal tract model was used to study the changes occurring in the BC films during passage through the gastrointestinal tract. Moreover, the cytotoxicity of the BC films against 3T3 mouse embryo fibroblasts was evaluated.
BC1 and BC2 showed equivalent density, WVP and maximum tensile strength. The percentage of bactericidal efficiency of BC1 and BC2 with adsorbed bLF (BC1+bLF and BC2+bLF, respectively) in the standalone films and in inoculated fresh sausages, was similar against E. coli (mean reduction 69 % in the films per se versus 94 % in the sausages) and S. aureus (mean reduction 97 % in the films per se versus 36 % in the case sausages). Moreover, the BC1+bLF and BC2+bLF films significantly hindered the specific growth rate of both bacteria. Finally, no relevant cytotoxicity against 3T3 fibroblasts was found for the films before and after the simulated digestion. BC films with adsorbed bLF may constitute an approach in the development of bio-based edible antimicrobial packaging systems.The authors would like to acknowledge Portuguese Foundation
for Science and Technology (Fundação para a Ciência e Tecnologia)
for the research grants: Jorge Padrão SFRH/BD/64901/2009, Sara
Gonçalves SFRH/BD/63578/2009, João Pedro Silva SFRH/BPD/
64958/2009, Ana Cristina Pinheiro SFRH/BPD/101181/2014. V.
Sencadas thanks support from the COST Action MP1206: “Electrospun
nano-fibres for bio inspired composite materials and innovative
industrial applications” and MP1301: “New Generation
Biomimetic and Customized Implants for Bone Engineering”. The
authors would also like to thank the co-funded by the Programa
Operacional Regional do Norte (ON.2 e O Novo Norte), QREN,
FEDER Projects “BioHealth e Biotechnology and Bioengineering
approaches to improve health quality”, Ref. NORTE-07-0124-
FEDER-000027; “BioInd e Biotechnology and Bioengineering for
improved Industrial and Agro-Food processes”, REF. NORTE-07-
0124-FEDER-000028; Strategic Project PEST-C/FIS/UI607/2014;
Matepro eOptimizing Materials and Processes”, ref. NORTE-07-
0124-FEDER-000037; Strategic Project PEst-OE/EQB/LA0023/2013
and project ref. RECI/BBB-EBI/0179/2012 (project number FCOMP-
01-0124-FEDER-027462). Finally, the authors thank the Fundação
para a Ciência e Tecnologia for the strategic funding from the UID/
BIO/04469/2013 unit
Recognition of energy and/or sound related activities performed by aged
In this final year project, the author explored the application of deep learning for audio classification, with a focus on multi-class and multi-label classification of various sound classes found in audio files. Examples of these sound classes include door sounds, toilet flushing, washing machines, and other typical household noises. The primary objective was to monitor the daily activities of elderly individuals by analyzing audio captured from their electronic devices, offering valuable insights into their daily routines, and helping to detect potential safety concerns.
The author employed convolutional neural networks (CNNs) in the project, as they are highly effective in image and signal processing tasks, making them suitable for audio classification problems. The project also involved experimenting with data augmentation and pre-processing techniques to enhance the model's performance and resilience to different noises and disturbances.
To develop the deep learning model, the author collected several labelled audio samples from a variety of sources and divided them into training, validation, and testing sets, ensuring a fair evaluation of the model's performance. Metrics such as accuracy, F1-score, and confusion matrix were utilized to assess the model's efficiency. The results suggested that the proposed approach can effectively detect ambient sounds, forming the basis for monitoring elderly activities and identifying unusual patterns, potentially contributing to their safety and well-being.
In conclusion, this final year project demonstrates the potential of deep learning techniques, particularly CNNs, for audio classification in monitoring the daily activities of elderly individuals using audio data from their mobile/electronic devices. The outcomes of this project hold significant implications for elderly care support and offer valuable information for researchers and healthcare professionals in the field of geriatrics.Bachelor of Engineering (Electrical and Electronic Engineering
Induction and inhibition of film yeast from fermented bamboo shoot by seasoning plants
Three samples of fermented bamboo shoot taken from a village in Amphur Kokpho, Pattani Province, were microbiologically examined. Total viable count was between at 104-105 cfu/ml while pH range was between 3.4-4.4. Isolation and identification of film yeast on surface of fermented liquid revealed Saccharomyces cerevisiae J1, Candida krusei J2 and Candida krusei J3. When film yeast was cultivated in liquid culture with different NaCl concentrations (0, 2.5, 5 and 7.5% (w/v)), all species tolerated 2.5% NaCl addition. However, growth decreased depending on NaCl concentration. S. cerevisiae J1 grew faster than C. krusei J2 and C. krusei J3. The cultivation of film yeast in medium with different agar concentrations (0.3, 0.5, 1 and 1.5% (w/v)) within 24 h showed that 0.3% was the optimal agar concentration. Seasoning plants (garlic, ginger, galangal, lemon grass, lesser galangal, clove, kaffir lime, garcinia and shallot) were extracted with water (3% (w/v)) and tested for growth inhibition. Results showed the clove extract inhibited all yeast strains within 12 h and after that the efficiency of inhibition was decreased. At low concentration of 0.75% (w/v) clove extract could inhibit film yeast in fermented bamboo shoot
Morphogenesis investigations of Saccharomyces cerevisiae using the mutant J19 with pseudohyphae
Reengineering Project at TPM
This project focuses on a reengineering project at the Siam TPM Co., a joint venture between The Siam Group and Bokuta Corporation of Japsn
Viability of Lactobacillus plantarum TISTR 2083 in protectant during low-temperature drying and storage
Low-temperature drying was applied as simple and low cost drying technique for the production of dried Lactobacillus plantarum TISTR 2083, which was isolated from traditional starter of Ka-nom Tuay-fu. To improve the survival of L. plantarum TISTR 2083 during drying and storage, five different protectants and two carrier materials were investigated. These include sucrose, trehalose, maltodextrin, skim milk, and L-glutamate sodium salt (L-GSS) as protectant and rice starch and rice flour as carrier material. Whereas, skim milk as protectant with rice starch resulted in higher viable cell (8.71 log CFU/g) after drying by hot air oven at 40 °C. Different concentration 5, 10, and 15% (w/v) skim milk also investigated to check the effect of skim milk concentration on cell viability. L. plantarum TISTR 2083 starter powder was in different storage conditions to check the storage stability. After 90 days of storage, starter powder stored at 4 °C with silica gel and without silica gel had more than 80% survival rate, while there was no viable cell that stored in room temperature with silica gel. The result showed the production and storage conditions of high viability L. plantarum TISTR 2083, which can be used as starter culture for further fermented product development and as probiotic
Extending the shelf-life of refrigerated green mussel (Perna viridis) under modified atmosphere packaging
The effect of modified atmosphere packaging (MAP) on the keeping quality of green mussel stored at 4C was investigated.Inhibition of the bacterial growth increased proportionally to the CO2 concentration in the packaging, and maximuminhibition was achieved with 100% CO2. Mussel stored under CO2-enriched atmosphere had lower total volatile base, trimethylamineand TCA-soluble peptide contents than those stored in air (P<0.05). However, the increase in exudate loss wasobserved for samples packaged in high-CO2 atmosphere, suggesting the denaturation of muscle proteins by carbonic acidformed. The odor and flavor acceptability of CO2-enriched packaged samples, particularly with 80 and 100% CO2, wasaccepted throughout the storage of 12 days, compared with six days for those stored in air. Therefore, MAP with 80% CO2,10% O2 and 10% N2 was chosen as the optimum condition for extending the shelf-life of green mussel. Packaging withinclusion of O2 should be considered to avoid the outbreak of strictly anaerobic toxin producing bacteria
Ballard Power Systems: Fueling the Next Technological Revolution
Between 1979 and 2001 a small Canadian company emerged as the recognized leader in Proton Exchange Membrane fuel cell technology. Following research breakthroughs in the mid 1980s, the Ballard Fuel Cell had by the turn of the millennium become synonymous with automotive fuel cells. Though far from the only competitor, this Canadian company had managed to hold Its own vis-a-vis its much larger American competitors, including GM. It owed much of its success to an early preoccupation with engineering and science, followed by a later recognition that despite the undeniable importance of the technology, there would be no product without commercialization. In Ballard\u27s circumstances that meant looking for partners with deep pockets and a shared vision in the eventual rise of the fuel cell as the most radical new technology in the automotive and the larger energy generation, distribution, and delivery markets