Electrospinning of Polycaprolactone (PCL) and Gelatin Polymeric Fibers

Electrospinning is one of the commonly used polymeric fiber production technique, owing to its versatility and flexibility in spinning a wide range of polymers for various applications including tissue engineering. However, recent researches have been extensively focusing on exploring the electrospinnability of different polymers without fully realizing how the electrospinning parameters influence the electrospun fibrous structure, as the microstructure morphology will significantly affect the performance of electrospun membranes. The present work demonstrates the robustness of electrospinning technique in producing electrospun fibrous membranes with different microstructure morphology by altering the electrospinning parameters. Both PCL and gelatin solutions have been successfully transformed into electrospun fibrous membranes using an electrospinning machine. The PCL fibrous membranes consisted of beads and non-homogenous fibers while the gelatin membranes showed homogenous size of electrospun fibers. Results also revealed that the electrospinning parameters including solution and process parameters determined the microstructure morphology of electrospun membrane. The spindle-like beads in PCL membrane transformed into spherical size at higher solution concentration and applied voltage. Meanwhile, the gelatin membrane demonstrated similar morphology at different tip-collector distance. The size of gelatin fibers was also similar. Through this work, basic understanding on how the electrospinning parameters affect the morphology of different types of polymeric fibrous membrane can provide an insight for other researchers in facilitate production of electrospun membranes with desired microstructure morphology

Electrospinning of Polycaprolactone (PCL) and Gelatin Polymeric Fibers / Shing Chee Lim ...[et al.]

Electrospinning is one of the commonly used polymeric fiber production technique, owing to its versatility and flexibility in spinning a wide range of polymers for various applications including tissue engineering. However, recent researches have been extensively focusing on exploring the electrospinnability of different polymers without fully realizing how the electrospinning parameters influence the electrospun fibrous structure, as the microstructure morphology will significantly affect the performance of electrospun membranes. The present work demonstrates the robustness of electrospinning technique in producing electrospun fibrous membranes with different microstructure morphology by altering the electrospinning parameters. Both PCL and gelatin solutions have been successfully transformed into electrospun fibrous membranes using an electrospinning machine. The PCL fibrous membranes consisted of beads and non-homogenous fibers while the gelatin membranes showed homogenous size of electrospun fibers. Results also revealed that the electrospinning parameters including solution and process parameters determined the microstructure morphology of electrospun membrane. The spindle-like beads in PCL membrane transformed into spherical size at higher solution concentration and applied voltage. Meanwhile, the gelatin membrane demonstrated similar morphology at different tip-collector distance. The size of gelatin fibers was also similar. Through this work, basic understanding on how the electrospinning parameters affect the morphology of different types of polymeric fibrous membrane can provide an insight for other researchers in facilitate production of electrospun membranes with desired microstructure morphology

Synthetic and Natural Fibrous Scaffolds for Soft Tissue Engineering Applications / Weily Khoo ...[et al.]

Fibrous scaffolds have been extensively studied as grafts for damaged tissue, owing to their physical architecture mimicking the native tissues like articular cartilage and skin. Developing mechanical robust fibrous scaffolds is therefore a critical issue to prevent scaffold failure that limits their applications in tissue engineering. This paper demonstrates our latest development of synthetic and natural fibrous scaffolds having physical architectures and mechanical properties comparable to that of native biological soft tissues. Synthetic fibrous scaffold was produced from gelatin solution using electrospinning technique while natural fibrous scaffold was extracted from small intestinal submucosa (SIS) of cattle. The SIS membrane was first decellurized and further reinforced with alginate hydrogel to form 3D composite scaffold. The physical architectures of both synthetic and natural fibrous scaffolds including thickness and microstructure morphology were characterized. SIS fibrous membrane reinforced with alginate hydrogel demonstrated more than 10 times of increment in scaffold thickness. Through scanning electron microscope (SEM) visualization, the synthetic fibrous scaffold demonstrated microstructures that mimic nanometer fiber and porous structure of soft collagenous tissues. Uniaxial tensile and fracture tests were performed to determine the tensile properties and fracture toughness of fibrous scaffolds. Both types of scaffolds showed tensile strength (0.81 – 38.30 MPa) and fracture toughness (0.86 – 32.52 kJ/m2) comparable to natural soft collagenous tissues. The developed tissue engineered scaffolds not only exhibit physical architectures mimicking native tissue structures but also demonstrate mechanical properties comparable to the native soft tissues

Strategy on the production of bead free electrospun gelatin scaffolds

Electrospun scaffolds consist of micro-scale or nano-scale porous fibrous networks. These electrospun scaffolds had become increasingly popular in tissue engineering filed as it could provide nano-environment for cell culture and produced by using biodegrable polymer. One of the important key to provide such environment for cell culture is the porosity of the electrospun scaffolds as it is highly related with the cell-cell interaction. The porosity of the electrospun scaffolds could be affected by bead formation which is one of the common problems faced in electrospinning process. However, the formation of beads are difficult to be controlled as it depends on environmental factors such as humidity and operating temperature. Controlling these two environmental factors normally requires an expensive control system. This paper aims to solve the problem of bead formation by adjusting material concentration and process parameters without controlling the environmental factors. The parameters studied in this paper include polymer concentration, flow rate, distance between the syringe needle tip and collector and applied voltage. The microstructure of the electrospun scaffolds produced were visualised using scanning electron microscopy (SEM) and were analysed in terms of bead formation and fiber diameter. This study shows that polymer concentration is the best strategy to prevent bead formation in gelatin scaffolds while other process parameters such as applied voltage, distance between the syringe needle tip and the collector as well as flow rate can be used to control the fiber diameter. An understanding of the effects of each parameter provides a guideline to control microstructure morphology by producing bead-free electrospun gelatin scaffolds

Efficient micropropagation of Dendrobium aurantiacum from shoot explant

Embryogenic tissue culture (seed tissue culture) is a common practice in plant industry to speed up and mass production. However, the culture method is not widely adopted in most of the orchid species. Micro-size orchid seeds are difficult to obtain and collect due to ambiguous seed maturation period. Most of orchid seeds have no endosperm and highly dependent on the specific fungi for germination and survival. Micropropagation from shoot culture with meristem tissue is potentially be another alternative for mass propagation of orchid. Therefore, this study examine the potential of micropropagation technique by shoot culture in orchid, Dendrobium aurantiacum (F. Muell.) F. Muell. This study reported an effective aseptic technique to develop sterilized D. aurantiacum tissue in vitro. The callus induction and regeneration from shoot explant by utilization of different plant growth regulator had been examined in this study. Among the treatments, 20% sodium hypochlorite with 15 mins sterilization period showed the highest sterilization efficiency on explants with only 16.7±5.8% of contamination occurred after two weeks and obtained highest survival rate 73.3±5.8% after one month. Callus formed in all combinations of plant hormone treatments. Media treated with 10 mg/L 2,4-D showed the highest callus induction rate but browning condition occur after 3 months of culture. Cell count on callus proliferation showed a significant difference (p < 0.05) between control and treatments. In conclusion, micropropagation of D. aurantiacum had been shortened almost 9-12 months required for nature germination

Growth media derived from solid waste for orchid Dendrobium kingianum culture

Food waste and diaper waste contribute to top three ranking solid wastes in Malaysia. Many studies show that urine and food waste can be used as plant fertilizer but less attention has been given to the recycling of used diaper. Therefore, this study was conducted to formulate Dendrobium kingianum growing media by utilizing diaper waste and selected food waste: banana peels, coffee waste and eggshells. The chemical composition in diaper waste and food waste were determined by using ICP-OES method. Biochar derived from oil palm waste, sugarcane and sawdust were tested to reduce and neutralize the high ammonium content from diaper waste. Biochar derived from oil palm waste showed the best reduction of ammonium in diaper waste. Survival and growth performance of Dendrobium kingianum was observed and recorded. Results show that orchid in diaper formulated growth media T3 showed the best adaptation and growth performance with highest percentage of healthy leaves and number of absorption roots within 3 weeks observation period. These results revealed that diaper waste could be recycled as orchid growing media by formulating with food waste and biochar

Valorisation of biomass and diaper waste into a sustainable production of the medical mushroom Lingzhi Ganoderma lucidum

Global solid waste is expected to increase by at least 70% annually until year 2050. The mixture of solid waste including food waste from food industry and domestic diaper waste in landfills is causing environmental and human health issues. Nevertheless, food and diaper waste containing high lignocellulose can easily degrade using lignocellulolytic enzymes thereby converted into energy for the development and growth of mushroom. Therefore, this study explores the potential of recycling biomass waste from coffee ground, banana, eggshell, tea waste, sugarcane bagasse and sawdust and diaper waste as raw material for Lingzhi mushroom (Ganoderma lucidum) cultivation. Using 2% of diaper core with sawdust biowaste leading to the fastest 100% mushroom mycelium spreading completed in one month. The highest production yield is 71.45 g mushroom; this represents about 36% production biological efficiency compared to only 21% as in commercial substrate. The high mushroom substrate reduction of 73% reflect the valorisation of landfill waste. The metabolomics profiling showed that the Lingzhi mushroom produced is of high quality with a high content of triterpene being the bioactive compounds that are medically important for treating assorted disease and used as health supplement. In conclusion, our study proposed a potential resource management towards zero-waste and circular bioeconomy for high profitable mushroom cultivation

Characteristics and trends in global Edible Bird’s Nest (EBN) research (2002–2021):a review and bibliometric study

Edible bird’s nest (EBN) is a valuable animal bioproduct produced by Swiftlets in Southeast Asia. Numerous researchers reported that EBN has rich nutritional value and high bioactive potential with numerous therapeutic benefits. For the first time, this paper evaluated the EBN research knowledge to conduct an in-depth statistical analysis and identify research trends, advancements, and hotspots. For this purpose, a combined methodologies based on bibliometric analysis and literature review was adopted. In total, 148 publications related to research EBN from 2002 to 2021 were identified. Three research hotspots were reviewed and discussed: (i) authentication and identification of EBN, (ii) beneficial and therapeutic properties of EBN, and (iii) EBN as active ingredients for functional food development. EBN has excellent potential as a value-ingredient with beneficial properties for commercial applications. Finally, this study provides a comprehensive overview of the EBN research trends and describes some current challenges and trends, which will remain the research focus and potent tool for future food scientists working on EBN functional food development. Graphical abstract: [Figure not available: see fulltext.].</p