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In this study, a simple sugaring-out supported by liquid biphasic flotation technique combined with ultrasonication was introduced for the extraction of proteins from microalgae. Sugaring-out as a phase separation method is novel and has been used in the extraction of metal ions, biomolecules and drugs. But, its functioning in protein separation from microalgae is still unknown. In this work, the feasibility of sugaring-out coupled with ultrasound for the extraction of protein was investigated. Primary studies were carried out to examine the effect of sonication on the microalgae cell as well as the separation efficiency of the integrated method. Effect of various operating parameters such as the concentration of microalgae biomass, the location of sonication probe, sonication time, ultrasonic pulse mode (includes varying ON and OFF duration of sonication), concentration of glucose, types of sugar, concentration of acetonitrile and the flow rate in the flotation system for achieving a higher separation efficiency and yield of protein were assessed. Besides, a large-scale study of the integration method was conducted to verify the consistency of the followed technique. A maximum efficiency (86.38%) and yield (93.33%) were attained at the following optimized conditions: 0.6% biomass concentration, 200 g/L of glucose concentration, 100% acetonitrile concentration with 5 min of 5 s ON/10 s OFF pulse mode and at a flow rate of 100 cc/min. The results obtained for large scale were 85.25% and 92.24% for efficiency and yield respectively. The proposed liquid biphasic flotation assisted with ultrasound for protein separation employing sugaring-out demonstrates a high production and separation efficiency and is a cost-effective solution. More importantly, this method provides the possibility of extending its application for the extraction of other important biomolecules., (Copyright © 2018 Elsevier B.V. All rights reserved.)

Many wounds are unresponsive to currently available treatment techniques and therefore there is an immense need to explore suitable materials, including biomaterials, which could be considered as the crucial factor to accelerate the healing cascade. In this study, we fabricated polyhydroxyalkanoate-based antibacterial mats via an electrospinning technique. One-pot green synthesized graphene-decorated silver nanoparticles (GAg) were incorporated into the fibres of poly-3 hydroxybutarate-co-12 mol.% hydroxyhexanoate (P3HB-co-12 mol.% HHx), a co-polymer of the polyhydroxyalkanoate (PHA) family which is highly biocompatible, biodegradable, and flexible in nature. The synthesized PHA/GAg biomaterial has been characterized by field emission scanning electron microscopy (FESEM), elemental mapping, thermogravimetric analysis (TGA), UV-visible spectroscopy (UV-vis), and Fourier transform infrared spectroscopy (FTIR). An in vitro antibacterial analysis was performed to investigate the efficacy of PHA/GAg against gram-positive Staphylococcus aureus ( S. aureus ) strain 12,600 ATCC and gram-negative Escherichia coli ( E. coli ) strain 8739 ATCC. The results indicated that the PHA/GAg demonstrated significant reduction of S. aureus and E. coli as compared to bare PHA or PHA- reduced graphene oxide (rGO) in 2 h of time. The p value ( p < 0.05) was obtained by using a two-sample t -test distribution.

Following the importance of antler-type fruiting bodies of Ganoderma lucidum, in this study, the impact of main growth parameters such as ventilation and light on the development of antler-type fruiting bodies has been investigated together with the determination of physico-chemical properties of antler fruiting bodies. For this, the primordia bags of G. lucidum were kept under controlled ventilation to adjust the CO 2 produced by the mushrooms owing to its respiration under light and dark conditions. The bioactive compounds such as phenolics, flavonoids, water-soluble polysaccharides and ganoderic acid showed a two-fold increase in the antler-type fruiting bodies as compared to normal kidney-shaped fruiting bodies. It is assumed from this study that the antler type fruiting bodies are developed due to restricted ventilation which causes an increase in the level of CO 2 gas in the air as a result of respiration of mushroom. The shape and colour of antler fruiting bodies again dependent on the light provided in the growth chamber. This study also proves that with the manipulation of light and ventilation antler-type fruiting bodies of G. lucidum could be developed with higher quantity of bioactive compounds and with higher antioxidant potential., (Copyright © 2018 British Mycological Society. Published by Elsevier Ltd. All rights reserved.)

This study investigates the cultivation of Ganoderma lucidum using different agricultural biomasses from Malaysia. Five different combinations of rubber wood sawdust, empty fruit bunch fiber, and mesocarp fiber from oil palm, alone and in combination, were used to cultivate G. lucidum. Although all the substrate combinations worked well to grow the mushroom, the highest biological efficiency was obtained from the combination of empty fruit bunch fiber with sawdust. A total yield of 27% was obtained from empty fruit bunch fiber with sawdust, followed by sawdust (26%), empty fruit bunch fiber (19%), mesocarp fiber with sawdust (19%), and mesocarp fiber (16%). The quality of mushrooms was proved by proximate analysis and detection of phenolic compounds and flavonoids. The antioxidant activity verified by DPPH, ferric-reducing ability of plasma, and ABTS analyses revealed that the empty fruit bunch fiber with sawdust had higher activity than the other substrates.

Sonochemistry, an almost a century old technique was predominantly employed in the cleaning and extraction processes but this tool has now slowly gained tremendous attention in the synthesis of nanoparticles (NPs) where particles of sub-micron have been produced with great stability. Following this, ultrasonication techniques have been largely employed in graphene synthesis and its dispersion in various solvents which would conventionally take days and offers poor yield. Ultrasonic irradiation allows the production of thin-layered graphene oxide (GO) and reduced graphene oxide (RGO) of up to 1nm thickness and can be produced in single layers. With ultrasonic treatment, reactions were made easy whereby graphite can be directly exfoliated to graphene layers. Oxidation to GO can also be carried out within minutes and reduction to RGO is possible without the use of any reducing agents. In addition, various geometry of graphene can be produced such as scrolled graphene, sponge or foam graphene, smooth as well as those with rough edges, each serving its own unique purpose in various applications such as supercapacitor, catalysis, biomedical, etc. In ultrasonic-assisted reaction, deposition of metal NPs on graphene was more homogeneous with custom-made patterns such as core-shell formation, discs, clusters and specific deposition at the edges of graphene sheets. Graphene derivatives with the aid of ultrasonication are the perfect catalyst for various organic reactions as well as an excellent adsorbent. Reactions which used to take hours and days were significantly reduced to minutes with exceedingly high yields. In a more recent approach, sonophotocatalysis was employed for the combined effect of sonication and photocatalysis of metal deposited graphene. The system was highly efficient in organic dye adsorption. This review provides detailed fundamental concepts of ultrasonochemistry for the synthesis of graphene, its dispersion, exfoliation as well as its functionalization, with great emphasis only based on recent publications. Necessary parameters of sonication such as frequency, power input, sonication time, type of sonication as well as temperature and dual-frequency sonication are discussed in great length to provide an overview of the resultant graphene products., (Copyright © 2017 Elsevier B.V. All rights reserved.)

Graphene is one of the highly explored nanomaterials due to its unique and extraordinary properties. In this study, by utilizing a hydrothermal reduction method, graphene oxide (GO) was successfully converted to reduced graphene oxide (RGO) without using any toxic reducing agents. Following this, with the use of ultrasonic cavitation, profoundly stable few layer thick RGO nanodispersion was generated without employing any stabilizers or surfactants. During ultrasonication, shockwaves from the collapse of bubbles cause a higher dispersing energy to the graphene nanosheets which surpass the forces of Van der Waal's and π-π stacking and thus pave the way to form a stable aqueous nanodispersion of graphene. Ultrasonication systems with different power intensity have been employed to determine the optimum conditions for obtaining the most stable RGO dispersion. The optimised conditions of ultrasonic treatments led to the development of a very stable reduced graphene oxide (RGO) aqueous dispersion. The stability was observed for two years and was analyzed by using Zetasizer by measuring the particle size and zeta potential at regular intervals and found to have exceptional stability. The excellent stability at physiological pH promotes its utilization in nano drug delivery application as a carrier for Paclitaxel (Ptx), an anticancer drug. The in vitro cytotoxicity analysis of Ptx loaded RGO nanodispersion by MTT assay performed on the cell lines revealed the potential of the nanodispersion as a suitable drug carrier. Studies on normal lung cells, MRC-5 and nasopharyngeal cancer cells, HK-1 supported the biocompatibility of RGO-Ptx towards normal cell line. This investigation shows the potential of exceptionally stable RGO-Ptx nanodispersion in nano drug delivery applications., (Copyright © 2016 Elsevier B.V. All rights reserved.)

Sonophotocatalysis (SPC) is considered to be one of the important wastewater treatment techniques and hence attracted the attention of researchers to eliminate recalcitrant hazardous organic pollutants from aqueous phase. In general, SPC refers to the integrated use of ultrasonic sound waves, ultraviolet radiation and the addition of a semiconductor material which functions as a photocatalyst. Current research has brought numerous improvements in the SPC based treatment by opting visible light irradiation, nanocomposite catalysts and numerous catalyst supports for better stability and performance. This review accomplishes a critical analysis with respect to the recent advancements. The efficiency of SPC based treatments has been analyzed by considering the individual methods i.e. sonolysis, photocatalysis, sonophotolysis, sono-ozone, photo-Fenton and sono-Fenton. Besides, the essential parameters such as solution temperature, concentrations of initial pollutant and catalyst, initial pH, dosages of Fenton's reagent and hydrogen peroxide (H 2 O 2 ), ultrasonic power density, gas sparging, addition of radical scavenger, addition of carbon tetrachloride and methanol have been discussed with suggestions for the selection of optimum parameters. A higher synergistic pollutant removal rate has been reported during SPC treatment as compared to individual methods and the implementation of numerous doping materials and supports for the photocatalyst enhances the degradation rate of pollutants using DSPC under both visible and UV irradiation. Overall, SPC and DSPC based wastewater treatments are emerging as potential techniques as they provide effective solution in removing the recalcitrant organic pollutants and progressive research is expected to bring out superior treatment efficiency using these advanced technologies., Importance of This Review: The review has accomplished a thorough and a critical analysis of sonophotocatalysis (SPC) based on the recently published journals. Recent advancements in the doped sonophotocatalysis (DSPC) and the mechanisms behind synergistic enhancement in the pollutant degradation rate have been discussed with justifications. Besides, the possible future works are suggested for the advancements in sonophotocatalysis based treatment. This review will be beneficial for electing a SPC based method because of the accomplished sharp comparisons among the published results. The review includes current advancements of SPC based methods which aid for a low-cost and a large-scale wastewater treatment application., (Copyright © 2016 Elsevier B.V. All rights reserved.)

Ganoderma mushroom cultivated recently in Malaysia to produce chemically different nutritional fibers has attracted the attention of the local market. The extraction methods, molecular weight and degree of branching of (1-3; 1-6)-β-d-glucan polysaccharides is of prime importance to determine its antioxidant bioactivity. Therefore three extraction methods i.e. hot water extraction (HWE), soxhlet extraction (SE) and ultrasound assisted extraction (US) were employed to study the total content of (1-3; 1-6)-β-d-glucans, degree of branching, structural characteristics, monosaccharides composition, as well as the total yield of polysaccharides that could be obtained from the artificially cultivated Ganoderma. The physical characteristics by HPAEC-PAD, HPGPC and FTIR, as well as the antioxidant in vitro assays of DPPH scavenging activity and ferric reducing power (FRAP) indicated that (1-3; 1-6)-β-d-glucans of Malaysian mushroom have better antioxidant activity, higher molecular weight and optimal degree of branching when extracted by US in comparison with conventional methods., (Copyright © 2016 Elsevier B.V. All rights reserved.)

Coupling multiple frequencies in ultrasonic systems is one of the highly desired area of research for sonochemists, as it is known for producing synergistic effects on various ultrasonic reactions. In this study, the characteristics of a hexagonal-shaped triple frequency ultrasonic reactor with the combination frequencies of 28, 40 and 70kHz were studied. The results showed that uniform temperature increment was achieved throughout the reactor at all frequency combinations. On the other hand, sonochemiluminescence emission and degradation rate of Rhodamine B varies throughout different areas of the reactor, indicating the presence of acoustic 'hot spots' at certain areas of the reactor. Also, coupling dual and triple frequencies showed a decrease in the hydroxyl radical (OH) production, suggesting probable wave cancelling effect in the system. The results can therefore be served as a guide to optimize the usage of a triple frequency ultrasonic reactor for future applications., (Copyright © 2016 Elsevier B.V. All rights reserved.)

In this study, a sonochemical approach was utilised for the development of graphene-gold (G-Au) nanocomposite. Through the sonochemical method, simultaneous exfoliation of graphite and the reduction of gold chloride occurs to produce highly crystalline G-Au nanocomposite. The in situ growth of gold nanoparticles (AuNPs) took place on the surface of exfoliated few-layer graphene sheets. The G-Au nanocomposite was characterised by UV-vis, XRD, FTIR, TEM, XPS and Raman spectroscopy techniques. This G-Au nanocomposite was used to modify glassy carbon electrode (GCE) to fabricate an electrochemical sensor for the selective detection of nitric oxide (NO), a critical cancer biomarker. G-Au modified GCE exhibited an enhanced electrocatalytic response towards the oxidation of NO as compared to other control electrodes. The electrochemical detection of NO was investigated by linear sweep voltammetry analysis, utilising the G-Au modified GCE in a linear range of 10-5000μM which exhibited a limit of detection of 0.04μM (S/N=3). Furthermore, this enzyme-free G-Au/GCE exhibited an excellent selectivity towards NO in the presence of interferences. The synergistic effect of graphene and AuNPs, which facilitated exceptional electron-transfer processes between the electrolyte and the GCE thereby improving the sensing performance of the fabricated G-Au modified electrode with stable and reproducible responses. This G-Au nanocomposite introduces a new electrode material in the sensitive and selective detection of NO, a prominent biomarker of cancer., (Copyright © 2016 Elsevier B.V. All rights reserved.)

In this investigation, sisal fibres were treated with the combination of alkali and high intensity ultrasound (HIU) and their effects on the morphology, thermal properties of fibres and mechanical properties of their reinforced PP composites were studied. FTIR and FE-SEM results confirmed the removal of amorphous materials such as hemicellulose, lignin and other waxy materials after the combined treatments of alkali and ultrasound. X-ray diffraction analysis revealed an increase in the crystallinity of sisal fibres with an increase in the concentration of alkali. Thermogravimetric results revealed that the thermal stability of sisal fibres obtained with the combination of both alkali and ultrasound treatment was increased by 38.5°C as compared to the untreated fibres. Morphology of sisal fibre reinforced composites showed good interfacial interaction between fibres and matrix after the combined treatment. Tensile properties were increased for the combined treated sisal fibres reinforced PP composites as compared to the untreated and pure PP. Tensile modulus and strength increased by more than 50% and 10% respectively as compared to the untreated sisal fibre reinforced composite. It has been found that the combined treatment of alkali and ultrasound is effective and useful to remove the amorphous materials and hence to improve the mechanical and thermal properties., (Copyright © 2016 Elsevier B.V. All rights reserved.)

Polysaccharides of β-D-glucan configuration have well-known antioxidant activity against reactive free radicals generated from the oxidation of metabolic processes. In this study, β-D-glucan-polysaccharides extracted from Ganoderma lucidum were incorporated in palm olein based nanoemulsions which act as carrier systems to enhance the delivery and bioactivity of these polysaccharides and could be potentially useful for skin care applications. Initially response surface statistical design (Central Composite Design--CCD) was subjected to optimize the formulation variables of oil-in-water (O/W) nanoemulsions induced by ultrasound. The optimal formulation variables as predicted by CCD resulted in considerably improving the physical characteristics of ultrasonically formulated nanoemulsions by minimizing their droplet size, polydispersity index and viscosity. Moreover, the β-D-glucan-loaded nanoemulsions exhibited good stability over 90 days under different storage conditions (4 °C and 25 °C). The studies using palm olein based β-D-glucan-loaded nanoemulsion generated using ultrasound confirm higher antioxidant activity as compared to free β-D-glucan., (Copyright © 2015 Elsevier B.V. All rights reserved.)

Purpose: The high aspect ratio of carbon nanotubes (CNTs) allows the attachment of compounds that enhance the functionality of the drug vehicle. Considering this, use of CNTs as a multifunctional insulin carrier may be an interesting prospect to explore., Materials and Methods: The carboxylic acid groups were functionalized on the sidewalls of single-walled CNTs (SWCNTs) followed by diimidation to form amide bonds with the amine groups of the insulin., Results: Scanning transmission electron microscopy and transmission electron microscopy establish clear conjugation of insulin onto the surface of nanotube sidewalls. The incorporation of insulin further increased the solubility of SWCNTs in biological solution for the tested period of 5 months. Bicinchoninic acid assay confirms that 0.42 mg of insulin could be attached to every 1 mg of carboxylated SWCNTs., Conclusion: With the successful conjugation of insulin to SWCNTs, it opens up the potential use of SWCNTs as an insulin carrier which in need of further biological studies.

Rigorous research has been carried out regarding the cultivation of Ganoderma lucidum using different agricultural residues. Nevertheless, large-scale cultivation and the separation of active compounds of G. lucidum are still challenges for local farmers. The objective of this study was to evaluate the use of oil palm waste fibers such as empty fruit bunch fibers and mesocarp fibers as effective substrates for the growth of G. lucidum mycelia to study the possibility of solid-state cultivation and to determine the optimum conditions necessary for the growth of mycelia of this mushroom on these waste fibers. Various parameters such as temperature, pH, humidity, and carbon and nitrogen compositions required for the optimum growth of mycelia have been determined. Oil palm fibers are a vivid source of lignocellulose, and their availability in Malaysia is high compared to that of sawdust. G. lucidum is a wood-rotting fungi that can easily decay and utilize this lignocellulose biomass, a major agricultural waste in Malaysia.

Ultrasonic VialTweeter is used for the sonication of small volume samples. It contains a titanium block with 8 holes for vial insertion, to be used simultaneously for batch operation. In this investigation, the ultrasonic and sonochemical performance of ultrasonic VialTweeter has been evaluated at its different positions. Experimental results using calorimetry, ultrasonic capillary effect, sonochemiluminescence and degradation of Rhodamine B showed that the sonochemical activity differs greatly at different positions along the VialTweeter, with positions 3 and 4 showing the maximum efficiency whereas the positions 1 and 2 being the least effective positions. These results were further verified by acoustic pressure simulation, confirming that certain locations in the VialTweeter may not perform in the same way as others due to the variation in acoustic pressure at different locations., (Copyright © 2015 Elsevier B.V. All rights reserved.)

Background: A medium- and long-term perspective is required in human resource development to ensure that future needs and demands for oral healthcare are met by the most appropriate health professionals. This paper presents a case study of the Sultanate of Oman, one of the Gulf States with a current population of 3.8 million, which has initiated dental training through the creation of a dental college., Objectives: The objectives of this paper are first to describe trends in the dental workforce in Oman from 1990 to date and compare the dental workforce with its medical counterparts in Oman and with other countries, and second, to consider future dental workforce in the Sultanate., Methods: Data were collected from published sources, including the Ministry of Health (MoH), Ministry of Manpower (MoM), and Ministry of National Economy (MoNE)-Sultanate of Oman; the World Health Organization (WHO); World Bank; and the Central Intelligence Agency (CIA). Dentist-to-population ratios were compared nationally, regionally and globally for medicine and dentistry. Dental graduate outputs were mapped onto the local supply. Future trends were examined using population growth predictions, exploring the expected impact in relation to global, regional and European workforce densities., Results: Population growth in Oman is increasing at a rate of over 2% per year. Oman has historically been dependent upon an expatriate dental workforce with only 24% of the dentist workforce Omani in 2010 (n = 160). Subsequent to Oman Dental College (ODC) starting to qualify dental (BDS) graduates in 2012, there is an increase in the annual growth of the dentist workforce. On the assumption that all future dental graduates from ODC have an opportunity to practise in Oman, ODC graduates will boost the annual Omani dentist growth rate starting at 28% per annum from 2012 onwards, building capacity towards global (n = 1711) and regional levels (Gulf State: n = 2167) in the medium term., Conclusion: The output of dental graduates from Oman Dental College is improving the dentist-to-population ratio and helping the Sultanate to realize its aim of developing an Omani-majority dental workforce. The implications for retention of dentists and team training are discussed.

Designing a biosensor for versatile biomedical applications is a sophisticated task and how dedicatedly functionalized fullerene (C60) can perform on this stage is a challenge for today and tomorrow's nanoscience and nanotechnology. Since the invention of biosensor, many ideas and methods have been invested to upgrade the functionality of biosensors. Due to special physicochemical characteristics, the novel carbon material "fullerene" adds a new dimension to the construction of highly sensitive biosensors. The prominent aspects of fullerene explain its outstanding performance in biosensing devices as a mediator, e.g. fullerene in organic solvents exhibits five stages of reversible oxidation/reduction, and hence fullerene can work either as an electrophile or nucleophile. Fullerene is stable and its spherical structure produces an angle strain which allows it to undergo characteristic reactions of addition to double bonds (hybridization which turns from sp(2) to sp(3)). Research activities are being conducted worldwide to invent a variety of methods of fullerene functionalization with a purpose of incorporating it effectively in biosensor devices. The different types of functionalization methods include modification of fullerene into water soluble derivatives and conjugation with enzymes and/or other biomolecules, e.g. urease, glucose oxidase, hemoglobin, myoglobin (Mb), conjugation with metals e.g. gold (Au), chitosan (CS), ferrocene (Fc), etc. to enhance the sensitivity of biosensors. The state-of-the-art research on fullerene functionalization and its application in sensor devices has proven that fullerene can be implemented successfully in preparing biosensors to detect glucose level in blood serum, urea level in urine solution, hemoglobin, immunoglobulin, glutathione in real sample for pathological purpose, to identify doping abuse, to analyze pharmaceutical preparation and even to detect cancer and tumor cells at an earlier stage. Employing fullerene-metal matrix for the detection of tumor and cancer cells is also possible by the inclusion of fullerene in single-walled carbon nanotubes (SWCNTs) known as peapods as well as in double-walled carbon nanotubes (DWCNTs), to augment the effectiveness of biosensors. This review discusses various approaches that have been reported for functionalizing fullerene (C60) derivatives and their application in different types of biosensor fabrication., (Copyright © 2014 Elsevier B.V. All rights reserved.)

Cancer nanotherapeutics is beginning to overwhelm the global research and viewed to be the revolutionary treatment regime in the medical field. This investigation describes the development of a stable nanostructured lipid carrier (NLC) system as carrier for Tamoxifen (TAM). The TAM-loaded NLC (TAM-NLC) developed with 200mg of TAM showed a spherical particle with the size of 46.6nm, polydispersity index of 0.267, entrapment efficiency of 99.74% and with the zeta potential of -23.78mV. Besides, the equivalent cytotoxicity of TAM and TAM-NLC to human (MCF-7) and mice (4T1) mammary breast cancer cell lines were observed. Incubating the formulation at the physiological pH resulted into reduced Ostwald ripening rate but without any significant change in the absorptivity. When coupled with the measurements of zeta potential and Ostwald ripening rate, the absorbance assay may be used to predict the long-term stability of drug-loaded nanoparticle formulations. The results of the study also suggest that TAM-NLC is a promising drug delivery system for breast cancer therapy. This is the first encouraging report on the in vitro effect of TAM-NLC against human and mouse mammary adenocarcinoma cell lines., (Copyright © 2013 Elsevier B.V. All rights reserved.)