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This study aims to evaluate the effect of cell immobilization on bioactive property of lactobacilli‐fermented soymilk.

Agrowastes from durian (Durio zibethinus), cempedak (Artocarpus champeden), and mangosteen (Garcinia mangostana) were used as immobilizers for lactobacilli (Lactobacillus acidophilus FTDC 1331, L. acidophilus FTDC 2631, L. acidophilus FTDC 2333, L. acidophilus FTDC 1733, and L. bulgaricus FTCC 0411) in soymilk fermentation. Fermented soymilk was stored at different temperatures (4°C, 25°C and 37°C) for 168 h and sampled for analyses periodically.

Scanning electron micrographs showed that cells of lactobacilli were immobilized onto the matrix of agrowastes powder. The proteolytic activity was higher in soymilk supplemented with immobilized lactobacilli at 37°C and 25°C compared to that at 4°C. Soymilk fermented by cells immobilized on cempedak rind powder showed higher proteolytic activity (p<0.0001), followed by durian and mangosteen rinds powder (p<0.001). The highest ACE inhibitory activity was also found in soymilk fermented by cells immobilized on cempedak rind powder for all temperatures studied (p<0.0001). In addition, ACE inhibitory activity was higher in soymilk fermented at 37°C, compared to 25°C and 4°C (p<0.0001).

The results in the paper show that cell immobilization enhances the bioactive property of fermented soymilk, in terms of proteolysis and in‐vitro ACE inhibitory activity.

Traditional analytical methods are often time-consuming and require bulky instruments, making their widespread implementation challenging. This paper aims to represent the principal concepts of biosensors as an introduction of this technology to readers and offers a comprehensive understanding of its functions.

The authors provide descriptions of the components, characteristics and advantages of biosensors along with the immobilization methods, followed by a brief discussion.

A biosensor is an analytical device comprising a specific biomolecule and a transducer in conjunction with an output system. The biomolecule recognizes a specific target which leads to a change in physicochemical properties of a system. This biorecognition phenomenon is later converted into a detectable signal by the transducer. Biosensors can essentially serve as rapid and cost-effective devices with excellent sensitivity and specificity for critical purposes in innumerable fields, ranging from scientific research to day-to-day applications.

Here, the authors explain and discuss the approaches and challenges with the aim of leading to an interest in biosensor development and improving their applications.

The purpose of this paper is to evaluate the possibility of a new biocatalyst prepared by kefir cells immobilization on grape stalks (GS) to reduce quickly and efficiently the Biochemical Oxygen Demand (BOD) and Chemical Oxygen Demand (COD) of the waste whey during its fermentation producing potable ethanol.

Many batch whey fermentations were carried out in order the effect of various conditions (pH, temperature) on 14C-labeled lactose uptake rate by the GS-immobilized kefir cells and consequently on fermentation rate as well as on ethanol production and whey BOD and COD reduction to be determined.

It has been illustrated that GS-biocatalyst was suitable for whey BOD and COD reduction by about 32 and 25 percent, respectively during whey alcoholic fermentation at 30°C and pH 5.5 in only ten hours, producing about 3.30 percent w/v of ethanol.

The findings of this research may enhance the existing literature on whey exploitation, for the first time focussing on the use of cheap and abundant GS as support for kefir immobilization during whey fermentation, which is potentially acceptable by industries in order to reduce fast and easily the whey polluting load and produce ethanol.

Olfaction plays a very important role in daily life. The olfactory system has the ability to recognize, discriminate and identify thousands of odorant compounds with extremely high sensitivity and specificity. The research on olfactory system has very important values in exploring the mechanisms of information processing in the other sensory nervous systems and brain. Recently, with the development of molecular biological and microelectronics technology research, the study of olfactory cell-based sensors has made great progress. The purpose of this paper is to provide details of recent developments in olfactory cell-based sensors.

Following an introduction, this paper first discusses some olfactory cell-based biosensors, which focus on the light-addressable potentiometric sensors and the microelectrode arrays. Second, surface modification, microfabrication and microfluidic technology which can improve the efficiency of cell immobilization will be summarized. The research trends of olfactory cell-based sensor in future will be proposed.

This paper shows that the biosensors’ performance is expected to be greatly improved due to the fast development of nanotechnology, optical technology and microelectronics. More and more emerging intelligent olfactory sensors will have a promising prospect in many application fields, including food quality and safety assessment, environmental monitor and human diseases detection.

This paper provides a detailed and timely review of the rapidly growing research in the olfactory cell-based sensors.

The purpose of this paper is to present a topology-based tissue scaffold design methodology to accurately represent the heterogeneous internal architecture of tissues/organs.

An image analysis technique is used that digitizes the topology information contained in medical images of tissues/organs. A weighted topology reconstruction algorithm is implemented to represent the heterogeneity with parametric functions. The parametric functions are then used to map the spatial material distribution following voxelization. The generated chronological information yields hierarchical tool-path points which are directly transferred to the three-dimensional (3D) bio-printer through a proposed generic platform called Application Program Interface (API). This seamless data corridor between design (virtual) and fabrication (physical) ensures the manufacturability of personalized heterogeneous porous scaffold structure without any CAD/STL file.

The proposed methodology is implemented to verify the effectiveness of the approach and the designed example structures are bio-fabricated with a deposition-based bio-additive manufacturing system. The designed and fabricated heterogeneous structures are evaluated which shows conforming porosity distribution compared to uniform method.

In bio-fabrication process, the generated bio-models with boundary representation (B-rep) or surface tessellation (mesh) do not capture the internal architectural information. This paper provides a design methodology for scaffold structure mimicking the native tissue/organ architecture and direct fabricating the structure without reconstructing the CAD model. Therefore, designing and direct bio-printing the heterogeneous topology of tissue scaffolds from medical images minimize the disparity between the internal architecture of target tissue and its scaffold.

The purpose of this paper is to adopt rapid prototyping (RP) technology to fabricate self‐hardening calcium phosphate composite (CPC) scaffolds with a controlled internal channel network to facilitate nutrient supplying and cell growth using RP technique and investigate their in vitro performance.

Porous scaffolds should possess branched channels to ensure uniform cell feeding and even flow of culture medium to promote uniform cell attachment and growth. A new three dimensional (3D) flow channel structure has been designed based on conversation of energy and flow. The CPC scaffold possessing such a channel network was made by indirect solid free form fabrication. Negative model of scaffold was designed by Pro/E software and its epoxy resin mold was fabricated on a sterolithography apparatus and the CPC slurry was filled in these molds. After CPC was self hardened, the mold was baked. The mold was removed by pyrolysis and then the designed scaffold was obtained.

The sizes of the fabricated scaffolds were consistent with the designed. The average compressive strength of the scaffold is approximately 6.0 MPa. Computational fluid dynamics and perfusion culture results showed that such a 3D flow channel arrangement would lead to a more uniform distribution of flow and cells and good transportation of nutrients.

The size errors of fabricated scaffolds could not escape and perfusion methods were difficult to control.

The basic design concept presented showed great promise for use in bone tissue engineering and fabrication method enhanced the versatility of scaffold fabrication. The designed scaffold structure made it possible to keep integrality of the scaffold when direct observation cells inside the channel by scanning electron microscopy (SEM).

The purpose of this paper is to speak about the production of biodiesel from waste cooking oil which serves as an alternate fuel in the absence of conventional fuels such as diesel and petrol. Though much research work was carried out using non-edible crops such as Jatropha and Pongamia, cooking oil utilized in bulk quantity is discarded as a waste. This is reused again as it contains more of esters that when combined with an alcohol in presence of an enzyme as a catalyst yields triglycerides (biodiesel).

The lipase producing strain Rhizopus oryzae and pure enzyme lipase is immobilized and treated with waste cooking oil for the production of FAME. Reaction parameters such as temperature, time, oil to acyl acceptor ratio and enzyme concentration were considered for purified lipase and in the case of Rhizopus oryzae, pH, olive oil concentration and rpm were considered for optimization studies. The response generated through each run were evaluated and analyzed through the central composited design of response surface methodology and thus the optimized reaction conditions were determined.

A high conversion (94.01 percent) was obtained for methanol when compared to methyl acetate (91.11 percent) and ethyl acetate (90.06 percent) through lipase catalyzed reaction at oil to solvent ratio of 1:3, enzyme concentration of 10 percent at 30°C after 24 h. Similarly, for methanol a high conversion (83.76 percent) was obtained at an optimum pH of 5.5, olive oil concentration 25 g/L and 150 rpm using Rhizopus oryzae when compared to methyl acetate (81.09 percent) and ethyl acetate (80.49 percent).

This research work implies that the acyl acceptors methyl acetate and ethyl acetate which are novel solvents for biodiesel production can also be used to obtain high yields as compared with methanol under optimized conditions.

This study aims to protect Lactobacillus plantarum and Enterococcus faecium encapsulated in alginate beads during stress treatments, such as high temperatures and concentrations of sodium chloride (NaCl) and sodium nitrite (NaNO₂).

Free and encapsulated probiotics were subjected to 70 and 80°C during 5, 10, 20 and 30 min. In addition, the probiotics were subjected to concentrations of 0.5, 1.0, 2.5 and 5.0 per cent NaCl and 0.5 and 1.0per cent of NaNO₂.

Free Lactobacillus plantarum was more resistant to heat than free Enterococcus faecium. Alginate-encapsulated Lactobacillus plantarum (ALP) also was more resistant to heat treatments than alginate-encapsulated Enterococcus faecium (AEF). After 30 min at 70°C, ALP showed levels about 6.9 log CFU/g while AEF presented 4.3 log CFU/g (p = 0.005). However, at 80°C, ALP maintained levels higher than 6 log CFU/g for up to 10 min, while AEF was able to maintain those levels only for approximately 5 min (p = 0.003). Encapsulation process provided adequate protection for both probiotics against NaCl. In relation to NaNO₂ concentrations, 0.5 and 1.0 per cent reduced viability of both probiotics (p = 0.014), either as free cells or as alginate-encapsulated forms.

Alginate beads containing probiotics is an interesting alternative for application in foods such as cooked meat products.

Alginate beads elaborated with milk powder, inulin and trehalose were effective to protect probiotics in stress situations similar to those can be found in the processing of foods, such as cooked meat products.

Radiotherapy relies on the delivery of radiation to cancer cells with millimetre accuracy, and immobilisation of patients is essential to minimise unwanted damage to surrounding healthy cells due to patient movement. Traditional thermoformed face masks can be uncomfortable and stressful for patients and may not be accurately fitted. The purpose of this study was to use 3D scanning and additive manufacturing to digitise this workflow and improve patient comfort and treatment outcomes.

The head of a volunteer was scanned using an Artec Leo optical scanner (Artec, Luxembourg) and ANSYS (Ansys, Canonsburg, USA) software was used to make two 3D models of the mask: one with a nose bridge and one open as would be used with optical surface guidance. Data based on measurements from ten pressure sensors around the face was used to perform topology optimisation, with the best designs 3D printed using fused deposition modelling (FDM) and tested on the volunteer with embedded pressure sensors.

The two facemasks proved to be significantly different in terms of restricting head movement inside the masks. The optimised mask with a nose bridge effectively restricted head movement in roll and yaw orientations and exhibited minimal deformation as compared to the open mask design and the thermoformed mask.

The proposed workflow allows customisation of masks for radiotherapy immobilisation using additive manufacturing and topology optimisation based on collected pressure sensor data. In the future, sensors could be embedded in masks to provide real-time feedback to clinicians during treatment.