Infrared Spectroscopy for Studying Structure and Aging Effects in Rhamnolipid Biosurfactants

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Designing Teenage Emotions with a Life of Their Own

In this chapter, two participatory design activities are described in which teenagers create lo-fi designs describing emotions and explain the rationale for their design choices. Designs annotating and describing emotions are categorised as anthropomorphic, abstract, object based, or biomorphic. The chapter concludes: (i) teenagers use a variety of visual metaphors to describe emotions, (ii) teenagers use anthropomorphic visual metaphors most often to describe emotions and (iii) teenagers make more use of abstract and biomorphic visual metaphors to describe ‘negative’ emotions. The effect of materials on designs is analysed, suggesting that teenagers are more likely to create designs describing emotions featuring anthropomorphic visual metaphors when using malleable three-dimensional materials. Suggestions are made for the use of externalisation and personification as part of interactive emotion displays within affective systems. A focus group evaluation of a prototype mobile app is described, which suggests that teenagers place more importance on an affective systems ability to support social relationships than they do its ability to support psychological development. This research will be of value to interaction designers and Child-Computer Interaction researchers seeking to understand how teenagers use different visual metaphors to describe different emotions

Bioreactor Rhamnolipid Production Using Palm Oil Agricultural Refinery By-Products

Palm fatty acid distillate (PFAD) and fatty acid methyl ester (FAME) are used by P. aeruginosa PAO1 to produce rhamnolipid biosurfactant. The process of fermentation producing of biosurfactant was structured in a 2 L bioreactor using 2% of PFAD and FAME as carbon sources in minimal medium and with a nitrogen concentration of 1 g L−1. Mass spectrometry results show the crude biosurfactant produced was predominantly monorhamnolipid (Rha-C10-C10) and dirhamnolipid (Rha-Rha-C10-C10) at 503 and 649 m/z value for both substrates. Maximum production of crude rhamnolipid for PFAD was 1.06 g L−1 whereas for FAME it was 2.1 g L−1, with a reduction in surface tension of Tris-HCl pH 8.0 solution to 28 mN m−1 and a critical micelle concentration (CMC) of 26 mg L−1 measured for both products. Furthermore, the 24 h emulsification indexes in kerosene, hexadecane, sunflower oil, and rapeseed oil using 1 g L−1 of crude rhamnolipid were in the range 20–50%. Consequently, PFAD and FAME, by-products from the agricultural refining of palm oil, may result in a product that has a higher added-value, rhamnolipid biosurfactant, in the process of integrated biorefinery

Production of Poly(3-Hydroxybutyrate-Co-3-Hydroxyvalerate) by Marine Archaea Haloferax mediterranei Dsm 1411 with Yeast Extract As Nutrient Source

In many countries, most of household goods are made from polymer or plastic. The polymer manufacturing industry has been relying on fossil fuel-based raw materials which are non-biodegradable. Plastics derived from these non-biodegradable sources will be difficult to degrade in nature, which in turn will pollute the environment and harm the ecosystem. One way to reduce the ecosystem damages caused by petroleum-based plastic is by using biodegradable materials for plastic industry, such as Polyhydroxyalkanoates (PHA). Poly (3-hydroxybutyrate-co-3-hydroxyvalerate) or PHBV is an example of PHA that can be produced by several types of microorganism, one of them is marine archaea Haloferax mediterranei. The objective of this study is to determine the productivity of marine archaea H. mediterranei cultures to produce PHBV with yeast extract as main nutrient sources. Experiments and analysis were conducted in triplicate and batch operating system. During the fermentation process, optical density, glucose levels, phosphorus levels, pH, and dry cell weight (DCW) were observed. The final product was then analysed using GC-MS to determine 3HB (3-hydroxybutyrate) and 3HV (3-hydroxyvalerate) fraction composition in the PHBV. The results showed that the maximum specific growth rate (m) and doubling time (Td) of the H. mediterranei were 0.1258 hours-1 and 5.51 hours, respectively. H. mediterranei biomass increased until it reached stationary phase after 95 hours incubation. The PHBV content, dry biomass and yield of PHBV to substrate were 2.62 g/L, 29.1% and 0.27 g/g, respectively

Infrared Spectroscopy for Studying Structure and Aging Effects in Rhamnolipid Biosurfactants

Biosurfactants are produced by microorganisms and represent amphiphilic compounds with polar and non-polar moieties; hence they can be used to stabilize emulsions, e.g., in the cosmetic and food sectors. Their structure and its changes when exposed to light and elevated temperature are yet to be fully understood. In this study, we demonstrate that attenuated total reflection infrared (ATR-IR) spectroscopy is a useful tool for the analysis of biosurfactants, using rhamnolipids produced by fermentation as an example. A key feature is that the analytical method does not require sample preparation despite the high viscosity of the purified natural product

Bioreactor Rhamnolipid Production Using Palm Oil Agricultural Refinery By-Products

From MDPI via Jisc Publications RouterHistory: accepted 2021-10-12, pub-electronic 2021-11-14Publication status: PublishedFunder: Geran Putra-IPM, Universiti Putra Malaysia; Grant(s): 9680100Palm fatty acid distillate (PFAD) and fatty acid methyl ester (FAME) are used by P. aeruginosa PAO1 to produce rhamnolipid biosurfactant. The process of fermentation producing of biosurfactant was structured in a 2 L bioreactor using 2% of PFAD and FAME as carbon sources in minimal medium and with a nitrogen concentration of 1 g L−1. Mass spectrometry results show the crude biosurfactant produced was predominantly monorhamnolipid (Rha-C10-C10) and dirhamnolipid (Rha-Rha-C10-C10) at 503 and 649 m/z value for both substrates. Maximum production of crude rhamnolipid for PFAD was 1.06 g L−1 whereas for FAME it was 2.1 g L−1, with a reduction in surface tension of Tris-HCl pH 8.0 solution to 28 mN m−1 and a critical micelle concentration (CMC) of 26 mg L−1 measured for both products. Furthermore, the 24 h emulsification indexes in kerosene, hexadecane, sunflower oil, and rapeseed oil using 1 g L−1 of crude rhamnolipid were in the range 20–50%. Consequently, PFAD and FAME, by-products from the agricultural refining of palm oil, may result in a product that has a higher added-value, rhamnolipid biosurfactant, in the process of integrated biorefinery

Integrated Cleaner Biocatalytic Process for Biodiesel Production from Crude Palm Oil Comparing to Refined Palm Oil

From MDPI via Jisc Publications RouterHistory: accepted 2021-06-14, pub-electronic 2021-06-15Publication status: PublishedFunder: Royal Golden Jubilee (RGJ) Ph.D. Programme; Grant(s): PHD/0018/2557Funder: Newton Fund; Grant(s): Newton Fund for Institutional Links 2019/2020An integrated cleaner biocatalyst process was performed for biodiesel production from crude palm oil (CPO) and refined palm oil (RPO). It was evaluated on process efficiency in terms of high purity of biodiesel as well as by-products without purification, less wastewater, less time consuming, and a simple downstream process. A first saponification step was carried out in both f CPO and RPO, a high purity of glycerol (86.25% and 87.5%) was achieved, respectively, while free fatty acids (FFASs) in soap were obtained after hexane extraction. High yields of FFASs were obtained from both CPO and RPO (98.83% and 90.94%). Subsequently, the FFAs were esterified to biodiesel by a biocatalyst of immobilized lipase. The highest biodiesel yields achieved were of 92.14% and 92.58% (CPO and RPO). Remarkably, biodiesel yields obtained from CPO and RPO achieved satisfactory values and the biocatalyst used could be reused for more than 16–17 cycles

Enhanced 4-hydroxybutyrate incorporation into the PHA terpolymer of Haloferax mediterranei by heterologous expression of 4-hydroxybutyrate-CoA transferases/synthetases

The polyhydroxyalkanoate terpolymer, P[(3HB)-co-(3HV)-co-(4HB)], is a promising plastic alternative for specialized applications, notably in medical and pharmaceutical sectors. Haloferax mediterranei (Hfx), an extreme halophile archaeon, is a P[(3HB)-co-(3HV)-co-(4HB)] terpolymer production host, however the native molar proportion of 4HB incorporated into the terpolymer is low. To improve incorporation, four 4-hydroxybutyrate-CoA transferases/synthetases from Clostridum kluyveri (OrfZ), Clostridium aminobutyricum (AbfT), Nitrosopumilis maritimus (NmCAT), and Cupriavidus necator N-1 (CnCAT), were heterologously expressed in H. mediterranei, and evaluated for their ability to supply 4HB-CoA for PHA terpolymer production. Growth, PHA synthesis, and polymer composition were evaluated for the four heterologous strains in shake-flask, with Hfx_NmCAT demonstrating superior growth, terpolymer titre and 4HB molar ratio. Co-feeding with γ-butyrolactone was optimised, and Hfx_NmCAT was further evaluated under fed-batch fermentation where a maximum PHA titre of 0.7g/L, containing 52mol% 4HB, was achieved. This is an order of magnitude improvement in 4HB terpolymer incorporation by H. mediterranei

Valorization of Aquatic Weed and Agricultural Residues for Innovative Biopolymer Production and Their Biodegradation

From MDPI via Jisc Publications RouterHistory: accepted 2021-08-17, pub-electronic 2021-08-24Publication status: PublishedFunder: National Research Council of Thailand (NRCT); Grant(s): National Research Council of Thailand (NRCT)In this work, water hyacinths, bagasse and rice straw were valorized to produce an innovative biopolymer. Serial steps of extraction, bleaching and conversion of cellulose to be carboxymethylcellulose (CMC) as well as the last steps of blending and molding were performed. The CMC was mixed with tapioca starch solution by a ratio of 9:18, and a plastic sizer of glycerol was varied at 2%, 4% and 6% by volume. In addition, bioplastic sheets were further determined in their properties and biodegradation. The results revealed that bioplastics with 6% glycerol showed a high moisture content of 23% and water solubility was increased by about 47.94% over 24 h. The effect of temperature on bioplastic stability was found in the ranges of 146.28–169.25 °C. Furthermore, bioplastic sheets with 2% glycerol could maintain their shape. Moreover, for texture analysis, the highest elastic texture in the range of 33.74–38.68% with 6% glycerol was used. Moreover, bioplastics were then tested for their biodegradation by landfill method. Under natural conditions, they degraded at about 10.75% by weight over 24 h after burying in 10 cm soil depth. After 144 h, bioplastics were completely decomposed. Successfully, the application of water, weed and agricultural wastes as raw materials to produce innovative bioplastic showed maximum benefits for an environmentally friendly product, which could also be a guideline for an alternative to replace synthetic plastics derived from petroleum