Showing papers in "Applied Biochemistry and Biotechnology in 2019"
TL;DR: Exosomes can bind specifically to HER2/Neu and are capable of delivering siRNA molecules against TPD52 gene into SKBR3 cell line down-regulating the gene expression up to 70%.
Abstract: Exosomes are the best options for gene targeting, because of their natural, nontoxic, non-immunogenic, biodegradable, and targetable properties. By engineering exosome-producing cells, ligands can be expressed fusing with exosomal surface proteins for targeting cancer cell receptors. In the present study, HER2-positive breast cancer cells were targeted with a modified exosome producing engineered HEK293T cell. For this purpose, the HEK293T cells were transduced by a lentiviral vector bearing-LAMP2b-DARPin G3 chimeric gene. Stable cells expressing the fusion protein were selected, and the exosomes produced by these cells were isolated from the culture medium, characterized, and then loaded with siRNA for subsequent delivery to the SKBR3 cells. Our results showed that stable HEK293T cells produced DARPin G3 on the surface of exosomes. These exosomes can bind specifically to HER2/Neu and are capable of delivering siRNA molecules against TPD52 gene into SKBR3 cell line down-regulating the gene expression up to 70%. Present approach is envisaged to facilitate genes and drugs transfer to HER2 cancer cells providing additional option for gene therapy and drug delivery.
125 citations
TL;DR: The different operating systems applied to these photosynthetic cultivations are critically discussed, and conclusions and perspectives are made concerning the best operating system for acquiring high cell densities and, consequently, high carotenoid accumulation.
Abstract: Microalgae cultivation, when compared to the growth of higher plants, presents many advantages such as faster growth, higher biomass productivity, and smaller land area requirement for cultivation. For this reason, microalgae are an alternative platform for carotenoid production when compared to the traditional sources. Currently, commercial microalgae production is not well developed but, fortunately, there are several studies aiming to make the large-scale production feasible by, for example, employing different cultivation systems. This review focuses on the main carotenoids from microalgae, comparing them to the traditional sources, as well as a critical analysis about different microalgae cultivation regimes that are currently available and applicable for carotenoid accumulation. Throughout this review paper, we present relevant information about the main commercial microalgae carotenoid producers; the comparison between carotenoid content from food, vegetables, fruits, and microalgae; and the great importance and impact of these molecule applications, such as in food (nutraceuticals and functional foods), cosmetics and pharmaceutical industries, feed (colorants and additives), and healthcare area. Lastly, the different operating systems applied to these photosynthetic cultivations are critically discussed, and conclusions and perspectives are made concerning the best operating system for acquiring high cell densities and, consequently, high carotenoid accumulation.
98 citations
TL;DR: A method for the high-throughput analysis of the relative lignin contents of Cryptomeria japonica samples over a wide concentration range, independent of the type of chemical pretreatment, was developed by using Fourier transform infrared spectroscopy.
Abstract: A method for the high-throughput analysis of the relative lignin contents of Cryptomeria japonica samples over a wide concentration range (3–73%), independent of the type of chemical pretreatment, was developed by using Fourier transform infrared spectroscopy. First, the assignments of the infrared absorbance related to lignin were reviewed. Then, various chemical treatments, including alkaline, acid, and hydrothermal processes, and a sodium chlorite oxidation treatment, were performed to prepare samples containing a wide range of different lignin contents. Principal component analysis indicated high variability among the chemical treatments in terms of the corresponding lignin contents as well as the resulting changes in the chemical structure of hemicellulose; this conclusion was supported by the loading vectors. The intensity of the key band of lignin at 1508 cm−1 was calculated using the absorbance at 2900 cm−1 as a reference; a reliable calibration curve with an R2 of 0.968 was obtained independent of the chemical treatment performed. This simple and rapid method for determining the lignin content is expected to be widely applicable for optimizing bioethanol production, as well as monitoring biomass degradation processes.
75 citations
TL;DR: The results revealed that the strength and hardness of the samples increased by increasing the sintering temperature up to 1150 °C, and the maximum values of hardness and compressive strength of the sintered THA were obtained at 1150-°C.
Abstract: Hydroxyapatite (HAp) is a bioactive and vital material which has found many applications in the biomedical and clinical fields. This bio-ceramic powder can be synthesized via different bio-waste materials. In this study, the production of natural nanohydroxyapatite was produced through calcination of untreated turkey femur-bone waste powder at 850 °C followed by ball milling the powder. The obtained powder was characterized using X-ray diffraction (XRD) and Fourier transform infrared spectroscopy (FTIR) analysis. The morphology, size, and elemental composition of obtained turkey hydroxyapatite (THA) particles were investigated by scanning electron microcopy (SEM), transmission electron microcopy (TEM), and energy dispersive spectroscopy (EDS) analysis, in which the average particle size of ball milled THA was found to be about 85 nm with a Ca/P ratio of 1.63. The powder was then cold pressed and later sintered at 850, 950, 1050, and 1150 °C to evaluate its mechanical properties in terms of compressive strength and hardness. The results revealed that the strength and hardness of the samples increased by increasing the sintering temperature up to 1150 °C. Finally, the maximum values of hardness and compressive strength of the sintered THA were obtained at 1150 °C (37.44 MPa and 3.2 GPa, respectively).
70 citations
TL;DR: Among these drugs, cinnarizine was found to be the most potent AR inhibitor (Ki: 2.07 ± 0.72 μM), and may be useful in the treatment and/or prevention of diabetic complications.
Abstract: Aldose reductase (AR) belongs to NADPH-dependent oxidoreductases and converts glucose to sorbitol in the polyol pathway. AR inhibition is essential to prevent diabetic complications. Here, AR was purified from sheep kidney using simple methods and determined the interactions between some calcium channel blockers and the enzyme. It was found that calcium channel blockers (cinnarizine, nilvadipine, amlodipine besylate, nifedipine, isradipine, and nitrendipine) exhibit potential inhibitor properties for sheep kidney AR with IC50 values in the range of 5.87–8.77 μM and Ki constants in the range of 2.07 ± 0.72–5.62 ± 1.53 μM. The calcium channel blockers showed different inhibition mechanisms. It was determined that all studied compounds showed competitive inhibition effect except for isradipine and nitrendipine. They showed non-competitive inhibition. Among these drugs, cinnarizine was found to be the most potent AR inhibitor (Ki: 2.07 ± 0.72 μM). They may be useful in the treatment and/or prevention of diabetic complications.
68 citations
TL;DR: Developing conductive scaffolds with electrical conductivity and porous structure composed of chitosan (CS) blending with graphene oxide (GO) for cardiac tissue engineering showed that the swelling, porosity, and conductive properties of GO/CS scaffolds could be modulated via adjusting the ratio of GO to CS.
Abstract: Cardiac tissue engineering is of great importance for therapeutic and pharmaceutical applications. The scaffolds that can provide electrical conductivity and structural organization will be highly beneficial for cardiac tissue engineering. Here, we developed conductive scaffolds with electrical conductivity and porous structure composed of chitosan (CS) blending with graphene oxide (GO) for cardiac tissue engineering. Our results showed that the swelling, porosity, and conductive properties of GO/CS scaffolds could be modulated via adjusting the ratio of GO to CS. More importantly, GO/CS scaffolds had a swelling ratio ranging from 23.20 to 27.38 (1000%) and their conductivity (0.134 S/m) fell in the range of reported conductivities for native cardiac tissue. Furthermore, we assessed their biological activity by seeding heart H9C2 cells in GO/CS scaffolds. Our data showed that these GO/CS scaffolds exhibited good cell viability, promotion of cell attachment and intercellular network formation, and upregulation of the cardiac-specific gene and protein expression involved in muscle conduction of electrical signals (Connexin-43). Overall, it is concluded that the GO/CS scaffolds promote the properties of cardiac tissue constructs. Our findings provide a new strategy and insight in developing new scaffolds for cardiac tissue engineering.
64 citations
TL;DR: In conclusion, the yeast grown in media with potato wastewater supplemented with 3% or 5% glycerol synthesized carotenoids, and their content in biomass did not exceed 230 μg/gd, and the level of pollution reduction by media was determined to be low.
Abstract: The objective of this study was to determine the possibility of simultaneous biosynthesis of lipids and carotenoids by the Rhodotorula yeast strains in media with waste glycerol and deproteinized potato wastewater and to determine the level of pollution reduction by media. On the basis of results obtained during the yeast microcultures in the Bioscreen C system, it was found that potato wastewater and glycerol can be used as components of media for Rhodotorula glutinis, Rhodotorula mucilaginosa, and Rhodotorula gracilis yeast strains. The amount of glycerol added to media higher than 10% significantly decreased the growth rate of yeast. The results of yeast culture in the laboratory shaker flasks showed a possibility of simultaneous production of lipids and carotenoids by R. glutinis, R. mucilaginosa, and R. gracilis yeast strains during cultivation in media containing only waste glycerol and deproteinized potato wastewater. A higher intracellular lipid content (approximately 15 g/100 gd.w.) was obtained for R. mucilaginosa and R. gracilis yeast biomass after cultivation in experimental media with waste glycerol and potato wastewater. In conclusion, the yeast grown in media with potato wastewater supplemented with 3% or 5% glycerol synthesized carotenoids, and their content in biomass did not exceed 230 μg/gd.w.
61 citations
TL;DR: The present article summarizes the recent expansion in the fabrication of the pristine/modified starch-based composite scaffolds by electrospinning along with their possible applications and the challenges to be overcome.
Abstract: Electrospinning a versatile and the most preferred technique for the fabrication of nanofibers has revolutionized by opening unlimited avenues in biomedical fields. Presently, the simultaneous functionalization and/or post-modification of as-spun nanofibers with biomolecules has been explored, to serve the distinct goals in the aforementioned field. Starch is one of the most abundant biopolymers on the earth. Besides, being biocompatible and biodegradable in nature, it has unprecedented properties of gelatinization and retrogradation. Therefore, starch has been used in numerous ways for wide range of applications. Keeping these properties in consideration, the present article summarizes the recent expansion in the fabrication of the pristine/modified starch-based composite scaffolds by electrospinning along with their possible applications. Apart from electrospinning technique, this review will also provide the comprehensive information on various other techniques employed in the fabrication of the starch-based nanofibers. Furthermore, we conclude with the challenges to be overcome in the fabrication of nanofibers by the electrospinning technique and future prospects of starch-based fabricated scaffolds for exploration of its applications.
57 citations
TL;DR: Results showed that hydroquinone could destroy the bacterial cell wall and membrane, increase permeability, lead leakage of intracellular substance affect synthesis of protein, and influence expression of genes.
Abstract: With growing concern about the possible risks and side effects of antibiotic drugs, more and more natural products with antibacterial activity are studied as the substitutes. In this paper, the antibacterial activity of hydroquinone and arbutin in Ainsliaea bonatii was investigated, which both displayed relatively strong antibacterial activity against Staphylococcus aureus (SA), methicillin-resistant S. aureus (MRSA), and extended spectrum β-lactamase S. aureus (ESBL-SA). The antibacterial mechanism of hydroquinone had been explored by scanning electron microscopy (SEM), alkaline phosphatase (AKP), and bacterial extracellular protein leakage. Results showed that hydroquinone could destroy the bacterial cell wall and membrane, increase permeability, lead leakage of intracellular substance affect synthesis of protein, and influence expression of genes.
53 citations
TL;DR: This research suggests a brand-new opening for skin wound healing therapy strategy by using wheat-derived exosomes due to its proliferative and migratory characteristics.
Abstract: Triticum aestivum plant extracts are often used as a natural healer in traditional medicine but which particles mainly have role in these processes are not scientifically proven. In other words, no attempts have been made to investigate the effects of wheat exosomes in regenerative medicine applications or drug development up to now. The current study was first time performed to demonstrate the activity of wheat exosomes in wound healing process using in vitro approaches. Although its fundamental wound healing process remains a mystery, in the current study, the efficiency of wheat grass juice–derived exosomes on cell viability and migration was examined. Increasing concentrations up to 200 μg/mL of the wheat exosome have yielded astonishing proliferative and migratory effects on endothelial, epithelial, and dermal fibroblast cells. RT-PCR analysis also showed collagen type I; mRNA levels were approximately twofold higher in expression after treating with 200 μg/mL wheat exosome. Additionally, Annexin V staining of apoptotic cells accompanied with the cell cycle analysis resulted with the reduction of the apoptotic cell number with no dispersion to the cell cycle analysis while plant exosomes have also increased tube-like structure formation of the endothelial cells. All in all, this research suggests a brand-new opening for skin wound healing therapy strategy by using wheat-derived exosomes due to its proliferative and migratory characteristics. Plant exosomes require a further research both clinically and in in vivo for wound healing drug development. Moreover, plant exosome therapy strategies would be safer and economical alternative for clinical wound healing.
50 citations
TL;DR: The present results indicate the potentiality of microalgae crude polysaccharides as a promising renewable bio resource in the development of plant bio stimulants.
Abstract: Microalgae are photosynthetic microorganisms that produce several bioactive molecules that have received considerable attention in scientific and industrial communities. Today, many plant biostimulants including seaweed extracts and polysaccharides are used in agriculture. However, microalgae have not been largely exploited in this field as a potential source of plant bio stimulants. This study investigated the biostimulatory effects of microalgae polysaccharides on different metabolomic and biochemical pathways related to plant defense. 0.2 mg mL−1 of crude polysaccharides extracted from four green microalgae strains was injected into tomato plants (Solanum lycopersicum). β-1,3-glucanase activity, lipid remodeling, phenylalanine ammonia lyase (PAL), Lipoxygenase (LOX), and antioxidant enzyme (APX, POD and CAT) activities were evaluated 48 h after treatment. Plants treated with crude polysaccharides extracted from. C. vulgaris and C. sorokiniana exhibited a significant increase in β-1,3-glucanase activity. Accordingly, C. sorokiniana crude polysaccharides had a significant stimulatory effect on PAL activity with a percentage increase of 188.73% compared to the control. GC/MS quantitative lipidomics analysis revealed that treatment with D. salina, C. sorokiniana, and C. reinhardtii crude polysaccharides increased PUFA content by 50.37%, 34.46%, and 33.37% respectively. Microalgae polysaccharides also enhanced stearic acid, palmitic acid, and VLCFA content, the optimal value of which increased by 45.50%, 32.83%, and 60.60% respectively under treatment with C. reinhardtii crude polysaccharides compared with the control. C. vulgaris and C. reinhardtii crude polysaccharides also exhibited higher APX and POD activity respectively. The present results therefore indicate the potentiality of microalgae crude polysaccharides as a promising renewable bio resource in the development plant bio stimulants.
TL;DR: The results indicated that the strain Klebsiella sp.
Abstract: Nitrogen removal by microorganisms has attracted increasing attention in wastewater treatment. In the present study, a heterotrophic nitrification bacterium was isolated from tannery wastewater and identified as Klebsiella sp. TN-10 based on phenotypic and phylogenetic characteristics. The optimal conditions for cell growth and nitrogen removal were investigated, and the results showed that the greatest ammonium removal rate and maximum biomass were achieved by using sodium pyruvate (7 g/L) as carbon source, C/N 12, pH 7, and temperature 30 °C. Under optimal conditions, the removal rate of ammonia nitrogen reached 96%. Besides, the growth characteristic and the ability of utilizing nitrate and nitrite were investigated. The results demonstrated that strain TN-10 exhibited excellent characteristics to remove both nitrate and nitrite, with the removal rate of 95.44% and 99.87%, respectively. In addition, the nitrite reductase (NiR) and nitrate reductase (NR) involved in denitrification were both active, with the activities of 0.0815 and 0.0283 U/mg proteins, respectively. Furthermore, the aggregation ability, auto-aggregation kinetics, and the relationship between zeta potentials and flocculating efficiency were determined. These results indicated that the strain Klebsiella sp. TN-10, with efficient heterotrophic nitrification-aerobic denitrification ability, has potential application in wastewater treatment.
TL;DR: Overall, the obtained results suggest the ternary blend of gelatin, cellulose acetate, and elastin as a good candidate for skin tissue engineering.
Abstract: Treatments of skin injuries caused by trauma and diseases are among the most considerable medical problems. The use of scaffolds that can cover the wound area and support cellular ingrowth has shown great promise. However, mimicking the physicochemical properties of the native skin extracellular matrix (ECM) is essential for the successful integration of these scaffolds. Elastin has been known as the second main protein-based component of the native skin ECM. In this research, scaffolds containing gelatin, cellulose acetate, and elastin were fabricated using electrospinning. Subsequently, the effects of soluble elastin on the physical, mechanical, and biological properties of the prepared scaffolds were studied. The results confirmed that the presence of elastin in the composition changed the fiber morphology from straight to ribbon-like structure and decreased the swelling ratio and degradation rate of the scaffold. In vitro experiments showed that elastin-containing scaffolds supported the attachment and proliferation of fibroblast cells. Overall, the obtained results suggest the ternary blend of gelatin, cellulose acetate, and elastin as a good candidate for skin tissue engineering.
TL;DR: This review provides the latest information on laccases from marine environments, their sources, biochemical properties, media composition for laccase production, and their applications in the bioremediation of industrial waste, especially focusing on dye decolorization.
Abstract: The discharge of industrial effluent creates environmental problems around the world and so necessitates the need for the economically expensive and sometimes technically problematic treatment of the wastewater. Laccases have enormous potential for the oxidative bioremediation of toxic xenobiotic compounds using only molecular oxygen as the sole cofactor for their reaction, and their application is regarded as environmentally friendly. Due to the low substrate specificity of laccases, they can oxidize a variety of substrates. Moreover, by using appropriate mediators, laccases can degrade a wide range of substrates, including those with structural complexity. Thus, laccases are an attractive alternative for wastewater treatment. Marine environments are rich in microorganisms that are exposed to extreme conditions, such as salinity, temperature, and pressure. Laccases from these microorganisms potentially have suitable properties that might be adaptive to bioremediation processes. This review provides the latest information on laccases from marine environments, their sources, biochemical properties, media composition for laccase production, and their applications in the bioremediation of industrial waste, especially focusing on dye decolorization.
TL;DR: The Paenibacillus sp.
Abstract: Interests in biosurfactant in industrial and environmental applications have increased considerably in recent years, owing to their potential benefits over synthetic counterparts. The present study aimed at analyzing the stability and oil removal efficiency of a new lipopeptide biosurfactant produced by Paenibacillus sp. D9 and its feasibility of its use in biotechnological applications. Paenibacillus sp. D9 was evaluated for optimal growth conditions and improved production yield of lipopeptide biosurfactant with variations in different substrate parameters such as carbon (C), nitrogen (N), C:N: ratio, metal supplements, pH, and temperature. Enhanced biosurfactant production was observed when using diesel fuel and ammonium sulfate as carbon and nitrogen source respectively. The maximum biosurfactant yield of 4.11 g/L by Paenibacillus sp. D9 occurred at a C/N ratio of 3:1, at pH 7.0, 30 °C, 4.0 mM MgSO4, and 1.5% inoculum size. The D9 biosurfactant was found to retain surface-active properties under the extreme conditions such as high thermal, acidic, alkaline, and salt concentration. The ability to emulsify further emphasizes its potential usage in biotechnological application. Additionally, the lipopeptide biosurfactant exhibited good performance in the degradation of highly toxic substances when compared with chemical surfactant, which proposes its probable application in biodegradation, microbial-enhanced oil recovery or bioremediation. Furthermore, the biosurfactants were effective in a test to stimulate the solubilization of hydrophobic pollutants in both liquid environments removing 49.1 to 65.1% diesel fuel including hydrophobic pollutants. The study highlights the usefulness of optimization of culture parameters and their effects on biosurfactant production, high stability, improved desorption, and solubilization of hydrophobic pollutants.
TL;DR: The Fe3O4@MCM-41-Cl@L-ASNase core–shell nanoparticles could successfully be used in industrial and medical applications and was more stable towards pH and temperature compared with soluble enzyme.
Abstract: This paper describes a new support that permits to efficient immobilization of L-asparaginase (L-ASNase). For this purpose, Fe3O4 magnetic nanoparticles were synthesized and coated by MCM-41. 3-chloropropyltrimethoxysilane (CPTMS) was used as a surface modifying agent for covalent immobilization of L-ASNase on the magnetic nanoparticles. The chemical structure; thermal, morphological, and magnetic properties; chemical composition; and zeta potential value of Fe3O4@MCM-41-Cl were characterized by Fourier transform infrared spectroscopy (FTIR), thermogravimetric analysis (TGA), differential thermal analysis (DTA), differential scanning calorimetry (DSC), vibrating sample magnetometer (VSM), scanning electron microscope (SEM), energy dispersive X-ray (EDX), X-ray diffraction patterns (XRD), and zeta-potential measurement. The immobilization efficiency onto Fe3O4@MCM-41-Cl was detected as 63%. The reusability, storage, pH, and thermal stabilities of the immobilized L-ASNase were investigated and compared to that of soluble one. The immobilized enzyme maintained 42.2% of its original activity after 18 cycles of reuse. Furthermore, it was more stable towards pH and temperature compared with soluble enzyme. The Michaelis–Menten kinetic properties of immobilized L-ASNase showed a lower Vmax and a similar Km compared to soluble L-ASNase. Immobilized enzyme had around 47 and 32.5% residual activity upon storage a period of 28 days at 4 and 25 °C, respectively. In conclusion, the Fe3O4@MCM-41-Cl@L-ASNase core–shell nanoparticles could successfully be used in industrial and medical applications.
TL;DR: The performance of methane production and microbial community structure were evaluated during co-digestion of rape straw and dairy manure at different S/I ratios in batch hemi-solid-state anaerobic digestion (HSS-AD) tests to provide useful information for enhancing efficient methaneproduction and advancing the understanding of the microbiome in HSS- AD.
Abstract: The substrate to inoculum (S/I) ratio is crucial for the rapid start-up of solid-state anaerobic digestion (SS-AD) systems. In this study, the performance of methane production and microbial community structure were evaluated during co-digestion of rape straw (RS) and dairy manure (DM) at different S/I ratios (2:3, 1:1, 2:1, 3:1, and 4:1) in batch hemi-solid-state anaerobic digestion (HSS-AD) tests. The highest methane yield of 209.1 mL/g VSadded and highest volumetric methane production of 0.4 L/(L·d) were achieved at S/I ratios of 2:3 and 2:1, respectively. Lower S/I ratios (1:2, 1:1, and 2:1) steadily produced biogas throughout the AD period, while higher S/I ratios (3:1 and 4:1) failed to produce biogas during the initial stage of AD because of excess accumulation of volatile fatty acids and low pH. The predominant bacteria and archaea in stable digesters were Firmicutes and acetoclastic Methanosaeta, respectively, while Bacteroidetes predominated and the relative abundance of hydrogenotrophic Methanobacterium increased significantly in acidic digesters. Amounts of bacteria and archaea were inhibited in acidic digesters. Our results provide useful information for enhancing efficient methane production and advancing the understanding of the microbiome in HSS-AD of RS and DM at different S/I ratios.
TL;DR: Feelings are provided for remediation of YILD and cogeneration of biofuel feedstock using the mixed culture of microalgae and yeast and the NH3-N and SO42− removal rates of the mixedculture were superior to mono cultures.
Abstract: The symbiosis potential of microalgae and yeast is inherited with distinct advantages, providing an economical venue for their scale-up application. To assess the advantage of the mixed culture of microalgae Chlorella vulgaris and yeast Yarrowia lipolytica for treatment of liquid digestate of yeast industry (YILD) and cogeneration of biofuel feedstock, the cell growth characteristic, the nutrient removal efficiency, the energy storage potential of the mono, and mixed culture were investigated. The results indicated that the biomass concentration of the mixed culture (1.39–1.56 g/L of 5 times dilution group and 1.23–1.53 g/L of 10 times dilution group) was higher than those of mono cultures. The NH3-N and SO42− removal rates of the mixed culture were superior to mono cultures. Besides the higher lipid yield (0.073–0.154 g/L of 5 times dilution group and 0.112–0.183 g/L of 10 times dilution group), the higher yield of higher heating value (20.06–29.76 kJ/L of 5 times dilution group and 21.83–29.85 kJ/L of 10 times dilution group) was also obtained in the mixed culture. This study provides feasibility for remediation of YILD and cogeneration of biofuel feedstock using the mixed culture of microalgae and yeast.
TL;DR: To recover a nitrogen resource from high-ammonia-nitrogen wastewater, two amphitrophic hydrogen-oxidizing bacteria (HOB), Paracoccus denitrificans Y5 and P. versutus D6, capable of nitrogen assimilation for single-cell protein (SCP) production were isolated.
Abstract: To recover a nitrogen resource from high-ammonia-nitrogen wastewater, two amphitrophic hydrogen-oxidizing bacteria (HOB), Paracoccus denitrificans Y5 and P. versutus D6, capable of nitrogen assimilation for single-cell protein (SCP) production were isolated. These two HOB strains could grow autotrophically with H2 as an electron donor, O2 as an electron acceptor, CO2 as a carbon source, and ammonia nitrogen (NH4+-N) as a nitrogen source. The cell molecular formulas of strains Y5 and D6 determined by autotrophic cultivation were C3.33H6.83O2.58N0.77 and C2.87H5.34O3.17N0.57, respectively. The isolated strains could synchronously remove NH4+-N and organic carbon and produce SCP via heterotrophic cultivation. The rates of removal of NH4+-N and soluble chemical oxygen demand reached 35.47 and 49.04%, respectively, for Y5 under mixotrophic cultivation conditions with biogas slurry as a substrate. SCP content of strains Y5 and D6 was 67.34-73.73% based on cell dry weight. Compared with soybean meal, the SCP of Y5 contained a variety of amino acids.
TL;DR: It was found that the fungus cannot produce IA from dilute acid pretreated and enzymatically saccharified wheat straw hydrolysate even at 100-fold dilution, which will be highly useful for developing a bioprocess technology for IA production from lignocellulosic feedstocks.
Abstract: Itaconic acid (IA; a building block platform chemical) is currently produced industrially from glucose by fermentation with Aspergillus terreus. In order to expand the use of IA, its production cost must be lowered. Lignocellulosic biomass has the potential to serve as low-cost source of sugars for IA production. It was found that the fungus cannot produce IA from dilute acid pretreated and enzymatically saccharified wheat straw hydrolysate even at 100-fold dilution. The effects of typical compounds (acetic acid, furfural, HMF and Mn2+, enzymes, CaSO4), culture conditions (initial pH, temperature, aeration), and medium components (KH2PO4, NH4NO3, CaCl2·2H2O, FeCl3·6H2O) on growth and IA production by A. terreus NRRL 1972 using mixed sugar substrate containing glucose, xylose, and arabinose (4:3:1, 80 g L-1) mimicking the wheat straw hydrolysate were investigated. Acetic acid, furfural, Mn2+, and enzymes were strong inhibitors to both growth and IA production from mixed sugars. Optimum culture conditions (pH 3.1, 33 °C, 200 rpm) and medium components (0.8 g KH2PO4, 3 g NH4NO3, 2.0 g CaCl2·2H2O, 0.83-3.33 mg FeCl3·6H2O per L) as well as tolerable levels of inhibitors (0.4 g acetic acid, < 0.1 g furfural, 100 mg HMF, < 5.0 ppb Mn2+, 24 mg CaSO4 per L) for mixed sugar utilization were established. The results will be highly useful for developing a bioprocess technology for IA production from lignocellulosic feedstocks.
TL;DR: Kinetics and statistics study showed that the higher S/I ratio could lead to VFA accumulation and result in low methane yield, which led to decrease in pH and accumulated unionized ammonia-N.
Abstract: The unbalanced nutrients of municipal solid waste (MSW), particularly high carbon contents, were regarded as a major limiting factor to anaerobic digestion process In this study, the addition of MSW in food waste (FW) feedstock to have a balanced C/N ratio was studied Different co-substrate mixtures with C/N ratio of 20 to 40 were subjected to anaerobic batch experiment at lab scale, under mesophilic conditions The biogas production decreased with the increase in C/N ratio due to insufficient availability of organic nitrogen for anaerobic microbial growth Specific biogas and methane yields were observed to be 827 and 47444 mL g−1VS, respectively, with volatile solids (VS) reduction rate of 88%, at C/N ratio of 20 Furthermore, the effect of the substrate to inoculum (S/I) ratio on digester performance was also studied The biogas production decreased with the increase in S/I ratio due to the formation of more volatile fatty acids (VFAs) which led to decrease in pH and accumulated unionized ammonia-N Specific biogas and methane yields were recorded to be 655 and 41020 mL g−1VS, with 64% rate of biodegradability at S/I ratio of 05 Kinetics and statistics study showed that the higher S/I ratio could lead to VFA accumulation and result in low methane yield
TL;DR: G. frondosa polysaccharides modulated the serum levels of oxidant factors such as superoxide dismutase, glutathione peroxidase, catalase, malondialdehyde, and reactive oxygen species, revealing their antioxidant properties and inhibited nuclear factor kappa B activities in the serum and kidneys of diabetic rats.
Abstract: Grifola frondosa is an edible fungus with a variety of potential pharmacological activities. This study investigates the hypoglycemic, anti-diabetic nephritic, and antioxidant properties of G. frondosa polysaccharides in diet-streptozotocin-induced diabetic rats. After a 4-week treatment with 100 mg/kg of metformin and 200 mg/kg of one of four different G. frondosa polysaccharide mixtures (especially GFPS3 and GFPS4), diabetic rats had enhanced body weight and suppressed plasma glucose, indicating the hypoglycemic activities of the G. frondosa polysaccharides. G. frondosa polysaccharides regulated the level of serum creatinine, blood urea nitrogen, N-acetyl-β-d-glucosaminidase, and albuminuria; inhibited the serum levels of interleukin (IL)-2, IL-6, and TNF-α; and enhanced the serum levels of matrix metalloproteinase 9 and interferon-α, confirming their anti-diabetic nephritic activities. G. frondosa polysaccharides ameliorated the pathological alterations in the kidneys of diabetic rats. Moreover, G. frondosa polysaccharides modulated the serum levels of oxidant factors such as superoxide dismutase, glutathione peroxidase, catalase, malondialdehyde, and reactive oxygen species, revealing their antioxidant properties. Furthermore, the administration of G. frondosa polysaccharides inhibited nuclear factor kappa B activities in the serum and kidneys. All of the data revealed that the activation of nuclear factor kappa B plays a central role in G. frondosa polysaccharide-mediated anti-diabetic and anti-nephritic activities.
TL;DR: Rec recombinant Escherichia coli coexpressing xylose reductase and glucose dehydrogenase is a promising candidate for xylitol production from xylOSE.
Abstract: Xylitol is an important functional sugar alcohol which is widely used in industries. To efficiently produce xylitol from xylose by xylose reductase in a single step, the coupled system and the coexpression system using xylose reductase (XR) from Rhizopus oryzae and glucose dehydrogenase (GDH) from Exiguobacterium sibiricum were constructed, the latter of which was used for cofactor regeneration. One hundred fifty grams/liter of xylose could be fully converted to xylitol by employing the two-enzyme coupled system with cell-free extract, and xylitol productivity of 21.2 g/L/h was reached by biotransformation in vitro. The whole-cell biocatalyst coexpressing xylose reductase and glucose dehydrogenase was successfully used to synthesize xylitol via enzymatic reduction of xylose. After optimization of the induction condition, the enzyme activity reached 1533 U/L. Two hundred grams/liter of xylose could be completely converted to xylitol, and the highest xylitol productivity of 6.37 g/L/h was obtained under the optimal transformation conditions. Thus, recombinant Escherichia coli coexpressing xylose reductase and glucose dehydrogenase is a promising candidate for xylitol production from xylose.
TL;DR: The studied parameters failed to predict survival or relapse in BC patients before surgery, but Elevated preoperative CA15.3 was shown to be directly related to tumor burden, which may improve its diagnostic capability.
Abstract: Diagnosis of breast cancer (BC) by using sensitive and specific biomarkers is necessary. Cell-free DNA is a candidate biomarker in various cancers. Contrasting, shorted uniformed DNA released from apoptotic non-diseased cells, DNA released from malignant cells varies in size. DNA integrity is a ratio between 247 and 115 bp. So, this study was designed to investigate the role of plasma ALU-247, ALU-115, and DNA integrity as possible diagnostic and prognostic markers in BC patients as compared to plasma CA15.3. The concentrations of selected parameters were determined for 40 patients with BC (2 stage I, 31 stage II, 2 stage III, and 5 stage IV) and 10 healthy volunteers by quantitative real-time PCR and ELISA. The sensitivities of ALU-247, ALU-115, and cfDI as biomarkers for BC were evaluated and compared with CA15.3. Also, disease-free survival and overall survival were estimated. For all parameters, the concentrations in patients were significantly higher than in the control group; association with tumor stage and high sensitivities was observed. The studied parameters failed to predict survival or relapse in BC patients before surgery. Plasma ALU-247, ALU-115, and DNA integrity may prove to have clinical utility in BC diagnosis. Elevated preoperative CA15.3 was shown to be directly related to tumor burden, which may improve its diagnostic capability. Those selected parameters could be effectively used together with plasma CA15.3 for BC screening at early stage. Furthermore, both ALU-247 and ALU-115 seem to be preoperative prognostic markers for BC.
TL;DR: The strain adaptation to molasses environment, performed in this study, is a rather simple and promising method for enhancement of LA production on the complex agro-industrial substrate.
Abstract: The aim of this study was to perform the adaptation of Lactobacillus paracasei NRRL B-4564 to substrate through adaptive evolution in order to ensure intensive substrate utilization and enhanced L (+)-lactic acid (LA) production on molasses-enriched potato stillage. To evaluate the strain response to environmental conditions exposed during the adaptation process and to select the best adapted cells, the antioxidant activity and LA-producing capability were assessed in batch fermentation. The most promising adapted strain was further used in a pulsed fed-batch mode. Among three selected adapted strains, L. paracasei A-22 showed considerably improved antioxidant capacity, demonstrating more than onefold higher 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical-scavenging rates compared to parent strain. This strain also exhibited superior LA production in batch fermentation and reached 89.4 g L−1 of LA, with a yield of 0.89 g g−1, a productivity of 1.49 g L−1 h−1, and an optical purity greater than 99%. Furthermore, in fed-batch mode L. paracasei A-22 resulted in 59% higher LA concentration (169.9 g L−1) compared to parent strain (107.1 g L−1). The strain adaptation to molasses environment, performed in this study, is a rather simple and promising method for enhancement of LA production on the complex agro-industrial substrate.
TL;DR: In this study, bioethanol was produced from the seaweed Gelidium amansii as biomass through separate hydrolysis and fermentation (SHF) processes, with activated carbon showing the best performance for hydroxymethylfurfural removal.
Abstract: In this study, bioethanol was produced from the seaweed Gelidium amansii as biomass through separate hydrolysis and fermentation (SHF) processes. The SHF processes examined in this study include thermal acid hydrolysis pretreatment, enzymatic saccharification, detoxification, and fermentation. Thermal acid hydrolysis pretreatment was conducted using H2SO4, with a slurry content of 8–16% and treatment time of 15–75 min. The optimal conditions for thermal acid hydrolysis pretreatment were 12% (w/v) seaweed slurry content and 180 mM H2SO4 at 121 °C for 45 min, at which 26.1 g/L galactose and 6.8 g/L glucose were produced. A monosaccharide (mainly glucose) was also obtained from the enzymatic saccharification of thermal acid hydrolysate using 16 U/mL Celluclast 1.5 L enzyme at 45 °C for 36 h. Detoxification was performed using the adsorption method with activated carbon, the overliming method with Ca (OH)2, and the ion exchange method with polyethyleneimine. Among those detoxification methods, activated carbon showed the best performance for hydroxymethylfurfural removal. Ethanol fermentation was performed using 12% (w/v) seaweed hydrolysate with Saccharomyces cerevisiae adapted to galactose as well as various detoxification treatments.
TL;DR: Vanillin has anti-neuroinflammatory properties and may act as a natural therapeutic agent for neuroinflammatory diseases, as suggested by the results of this study.
Abstract: Microglia, resident macrophages of the central nervous system (CNS), is responsible for immune responses and homeostasis of the CNS. Microglia plays a complex role in neuroinflammation, which has been implicated in neurodegenerative diseases such as Alzheimer's disease and Parkinson's disease. Therefore, therapeutic agents that suppress the microglia-mediated inflammatory response could potentially be used in the prevention or treatment of neurodegenerative diseases. Vanillin, a primary component of vanilla bean extract, has anti-inflammatory, anticancer, and antitumor properties. However, the effects of vanillin on the anti-neuroinflammatory responses of microglial cells are still poorly understood. In this study, we investigated the mechanism by which vanillin induces anti-neuroinflammatory responses in lipopolysaccharide (LPS)-stimulated BV-2 microglial cells. We found that vanillin significantly decreased the production of nitric oxide and pro-inflammatory cytokines, including interleukin (IL)-1β, tumor necrosis factor-α (TNF-α), and interleukin-6 (IL-6). Vanillin also reduced the protein levels of inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2), as well as the mRNA expression levels of IL-1β, TNF-α, and IL-6. Moreover, vanillin inhibited the phosphorylation of mitogen-activated protein kinases (MAPKs) and nuclear factor (NF)-κB. Collectively, these results suggest that vanillin has anti-neuroinflammatory properties and may act as a natural therapeutic agent for neuroinflammatory diseases.
TL;DR: BMED can be used for producing xylonic acid from fermentation broth and ways of improving the efficiency of BMED are highlighted.
Abstract: Preparation of xylonic acid from xylonate fermentation broth was studied in a four-chamber bipolar membrane electrodialysis (BMED) setup. The effects of metal-ion size, current density, and xylonate concentration on BMED were evaluated principally with respect to acid yield and partially with respect to efficiency and energy consumption. Sodium xylonate was more successful than potassium xylonate because of its smaller size and easier membrane penetrability for BMDE. Efficient electrodialysis was achieved using 50 mA/cm2 current density for 14 min; thus, we obtained 92% xylonic acid from 100 g/L sodium xylonate fermentation broth. In conclusion, BMED can be used for producing xylonic acid from fermentation broth. Moreover, this study highlights ways of improving the efficiency of BMED.
TL;DR: The paper reports the characterization of the growth kinetics of Actinobacillus succinogenes DSM 22257 using glucose as carbon source and results pointed out that no substrate inhibition was observed; acetic acid did not inhibit the cell growth and succinic acid production.
Abstract: Succinic acid is one of the most interesting platform chemicals that can be produced in a biorefinery approach. The paper reports the characterization of the growth kinetics of Actinobacillus succinogenes DSM 22257 using glucose as carbon source. Tests were carried out in a continuous bioreactor operated under controlled pH. Under steady-state conditions, the conversion process was characterized in terms of concentration of glucose, cells, acids, and pH. The effects of acid-succinic, acetic, and formic-concentration in the medium on fermentation performance were investigated. The fermentation was interpreted according to several models characterized by substrate and product inhibition. The selected kinetic model of biomass growth and of metabolite production described the microorganism growth rate under a broad interval of operating conditions. Under the investigated operating conditions, results pointed out that: no substrate inhibition was observed; acetic acid did not inhibit the cell growth and succinic acid production.
TL;DR: Alternative low-cost additives were evaluated in the saccharification of steam-exploded sugarcane bagasse using a commercial enzymatic cocktail and showed superior effects on glucose release during the hydrolysis, with gains of up to 36% when 8% soybean protein was used.
Abstract: A potential strategy to mitigate problems related to unproductive adsorption of enzymes onto lignin during the saccharification of lignocellulosic biomass is the addition of lignin-blocking agents to the hydrolysis reaction medium However, there is a clear need to find more cost-effective additives for use in large-scale processes Here, selected alternative low-cost additives were evaluated in the saccharification of steam-exploded sugarcane bagasse using a commercial enzymatic cocktail The addition of soybean protein, tryptone, peptone, and maize zein had positive effects on glucose release during the hydrolysis, with gains of up to 36% when 8% (w/w) soybean protein was used These improvements were superior to those obtained using bovine serum albumin (BSA), a much more expensive protein that has been widely reported for such an application Moreover, addition of soybean protein led to a saving of 48 h in the hydrolysis, corresponding to a 66% decrease in the reactor operation time required In order to achieve the same hydrolysis yield without the soybean additive, the enzyme loading would need to be increased by 50% FTIR spectroscopy and nitrogen elemental analysis revealed that the additives probably acted to reduce unproductive binding of cellulolytic enzymes onto the lignin portion of the sugarcane bagasse