Supercritical transesterification of vegetable oil and ethanol: temperature and residence time effects on phase formation and water content

Supercritical transesterification has emerged as a readily available alternative for biodiesel production since no catalyst is required, thereby generating fewer waste products. In this research, the supercritical transesterification of refined vegetable oil and aqueous ethanol was carried out at temperatures 400 to 480 °C and a 12:1 ethanol to oil molar ratio, to assess the effect of temperature and residence time in the formation of a homogeneous phase, effluent appearance and increased water content derived from glycerol etherification. The results showed that water was produced at temperatures higher than 400 °C, as expected from the occurrence of glycerol etherification, and that prolonged times resulted in gas and soot formation, indicating esters decomposition. Through water mass balances, it was possible to identify the set of operation conditions in which the water formed from glycerol etherification matched with the maximum expected according to the proposed reaction scheme.

La transesterificación supercrítica se ha propuesto como una alternativa para la producción de biodiesel ya que no requiere catalizador de esta manera se generan menos residuos. En esta investigación, la transesterificación supercrítica de aceite vegetal refinado y etanol acuoso se llevó a cabo a temperaturas en el rango 400 a 480 °C y relación molar etanol a aceite de 12:1, para evaluar el efecto de la temperatura y el tiempo de residencia en la formación de una fase homogénea, apariencia del efluente e incremento del contenido de agua resultado de las reacciones de eterificación del glicerol. Los resultados mostraron que se produjo agua a temperaturas mayores a 400°C, atribuida a la eterificación del glicerol, y que tiempos de residencia prolongados resultaron en formación de gas y hollín, indicativo de reacciones de descomposición de esteres. A través de balances de masa, fue posible identificar el conjunto de condiciones de operación a las cuales el agua formada por la eterificación del glicerol coincide con el valor máximo esperado de acuerdo con el esquema de reacción propuesto.

A transesterificação supercrítica foi proposta como uma alternativa para a produção de biodiesel porque não requer catalisador e, dessa forma, gera menos resíduos. Nesta pesquisa, a transesterificação supercrítica de aceite vegetal refinado e etanol acuoso foi conduzida a temperaturas entre 400 e 480 °C e uma relação molar de etanol e aceite de 12: 1, para avaliar o efeito da temperatura e do tempo de residência na formação de uma fase homogênea, apariência do efluente e aumento do conteúdo de água resultante das reações de eterificação do glicerol. Os resultados mostraram que se produziu água a temperaturas maiores que 400°C, atribuída à eterificação do glicerol, e que os tempos de residência prolongados resultaram na formação de gás e hollín, indicativo de reações de decomposição de ésteres. Por meio de balanças de massa, foi possível identificar o conjunto de condições de operação em que a água formada pela eterificação do glicerol coincide com o valor máximo esperado de acordo com o esquema de reação proposto.

The regulation of APGAT4 on the growth and lenvatinib resistance of hepatocellular carcinoma / 中华肝脏病杂志

Objective: To investigate the effect of 1-acyl-sn-glycerol-3-phosphate acyltransferaseδ (APGAT4) on the growth and lenvatinib resistance of hepatocellular carcinoma (HCC), and provide novel targets for HCC treatment. Methods: Using the bioinformatics methods to screen out upregulated genes in lenvatinib resistant cell lines from GEO dataset and survival related genes from TCGA dataset. Immumohistochemical staining was used to detect the expression AGPAT4 in HCC tissues, and its correlation with patients' survival. CCK8, EdU, cell cycle, and cell apoptosis assays were used to investigate the impact of role AGPAT4 on the proliferation and lenvatinib reistance of HCC cells. AGPAT4 stable knockdown cell line and subcutaneous nude mouse model were established to test the therapeutic effects of Lenvatinib. Analysis of variance was used to compare the differences between data sets. Results: APGAT4 was the common factor that predicted poor survival and Lenvatinib resistance. The mRNA and protein levels of APGAT4 were significantly upregulated in HCC tissues compared to the para-tumor tissues (P < 0.05). Using siRNA could significantly knocked down the mRNA and protein expression of APGAT4 in HCC cell lines Hep3B and HCCLM3. Compared with the control group, the proliferation ability of HCC cell lines (Hep3B and HCCLM3) in APGAT4 knockdown group was significantly inhibited, and the cell cycle was arrested in G2/M phase (P < 0.05). In addition, compared to the control group, HCC cell lines (Hep3B and HCCLM3) in APGAT4 knockdown group showed significant decrease in the Lenvatinib half maximal inhibitory concentration, and were more sensitive to lenvatinib-induced apoptosis (P < 0.05). In HCC subcutaneous nude mouse model, compared to the control group, the growth of tumor in APGAT4 knockdown group was significantly suppressed, and more apoptosis cells were induced (P < 0.05). Conclusion: APGAT4 promotes the growth and Lenvatinib resistance of HCC, which is a potential target for HCC treatment. Targeting APGAT4 treatment is conducive to inhibit the growth and Lenvatinib resistance of HCC.

Ovariectomy exacerbates glycerol-induced acute kidney injury in rats / A ovariectomia intensifica a lesão renal aguda induzida pelo glicerol em ratas

Objective: This study aimed to evaluate the effects of ovariectomy on glycerol-induced renal changes in rats. Methods: Twenty-four female Wistar rats were submitted to ovariectomized (OVX) or sham surgery. One week after surgery, the animals received an intramuscular injection (8ml/kg) of 50% glycerol or saline (0.15 M) solution. These animals were divided into the following groups (n=6 per group): Sham, sham-operated female rats injected with saline; OVX, ovariectomized female rats injected with saline; Sham+Gly, sham-operated female rats injected with glycerol; OVX+Gly, ovariectomized female rats injected with glycerol. All rats were euthanized 3 days after the injections and the kidneys were removed for histological and immunohistochemical studies. Blood and urine samples were also collected for renal function studies. Results: The OVX+Gly group presented higher creatinine serum levels, as well as greater fractional excretion of sodium and urinary flow than the Sham+Gly group. Histological lesions and tubulointerstitial staining for macrophages, nuclear factor-kappa B, and nitrotyrosine were more pronounced in the renal cortex of the OVX+Gly group compared to the Sham+Gly group. Conclusion: We conclude that ovariectomy aggravated changes in renal function and structure in glycerol-induced acute kidney injury by the intensification of the proinflammatory tissue response.

Objetivo: Avaliar os efeitos da ovariectomia nas alterações renais induzidas pelo glicerol em ratas. Métodos: Vinte e quatro ratas Wistar foram submetidas à ovariectomia (OVX) ou cirurgia sham (intervenção falsa). Uma semana após a cirurgia, os animais receberam injeção intramuscular (8ml/kg) de glicerol a 50% ou solução salina (0,15 M). As ratas foram divididas nos seguintes grupos (n=6 por grupo): Sham, fêmeas sham-operadas e injetadas com solução salina; OVX, fêmeas ovariectomizadas e injetadas com solução salina; Sham+Gly, fêmeas sham-operadas e injetados com glicerol; OVX+Gly, fêmeas ovariectomizadas e injetadas com glicerol. Todas as ratas foram eutanasiadas 3 dias após as injeções e os rins foram removidos para estudos histológicos e imuno-histoquímicos. Amostras de sangue e urina também foram coletadas para estudos de função renal. Resultados: O grupo OVX+Gly apresentou maiores níveis séricos de creatinina, assim como maiores fração de excreção de sódio e fluxo urinário do que o grupo Sham+Gly. As lesões histológicas e imunomarcação tubulointersticial para macrófagos, fator nuclear-kappa B e nitrotirosina foram mais pronunciadas no córtex renal do grupo OVX+Gly em comparação ao grupo Sham+Gly. Conclusão: Concluímos que a ovariectomia agravou as alterações na função e estrutura renal, na lesão renal aguda induzida por glicerol, pela intensificação da resposta tecidual pró-inflamatória.

Processamento e conservação de enxertos de pele: uma abordagem com foco nos métodos de criopreservação, liofilização e glicerolização / Skin grafts processing and conservation: an approach focusing on cryopreservation, freeze-drying and glycerol conservation methods

Introdução: o uso de substitutos cutâneos para o tratamento de diversas feridas graves é uma forma eficiente de prevenir infecções e favorecer o processo de reepitelização. No entanto, tecidos biológicos estão suscetíveis a degradação e contaminação. Por isso, devem ser submetidos a rigorosos protocolos de processamento e testes que comprovem suas contribuições benéficas e segurança de aplicação. Objetivo: trazer uma abordagem sobre as principais características dos métodos de criopreservação, glicerolização e liofilização e sua consequencia nos aspectos imunológicos, microbiológicos e de viabilidade tecidual de enxertos de pele humana. Metodologia: foi realizada uma busca online utilizando as palavras chaves "criopreservação", "liofilização", "glicerolização", "enxertos", "processamento tecidual" e "engenharia dos tecidos" em múltiplas combinações nos bancos de dados PubMed, LILACS e ScienceDirect. Resultados: 200 artigos científicos foram obtidos, 26 excluídos por duplicidade, 92 selecionados para leitura integral a partir da leitura de seus resumos e 27 utilizados na construção desta revisão. A liofilização e a glicerolização são métodos semelhantes considerando a viabilidade tecidual. O uso de glicerol traz como principal desvantagem sua citotoxicidade quando comparado aos outros métodos. A criopreservação mantém os tecidos viáveis. Contudo, pode ser mais cara e trazer riscos de transmissão de microorganismos patogênicos. De modo geral, não é bem estabelecido quais os melhores métodos de conservação para uma adequada conservação da viabilidade dos enxertos de pele. Considerações Finais: os 3 métodos, liofilização, glicerolização e criopreservação, possuem aplicabilidade na conservação de enxertos. A falta de padronização na aplicação de enxertos apesar de sua frequente aplicação e a escassez de estudos recentes sobre o tema justificam o presente estudo.

Introduction: the use of skin substitutes for treatment of several wounds is an efficient way to prevent infections and allow the re-epithelialization process. However, biological tissues are susceptible to degradation and contamination. Therefore, they must undergo rigorous processing and testing protocols that prove their beneficial contributions and application security. Objective:to bring an approach on the main characteristics of cryopreservation, freeze-drying and glycerol conservation methods and their implications on immunological, microbiological and tissue viability aspects when applied to human skin grafts. Methodology:a mostly online search was performed using the keywords "cryopreservation", "freeze-drying", "glycerol conservation", "grafts", "tissue processing" and "tissue engineering" in multiple combinations in PubMed, LILACS and ScienceDirect databases. Results: 200 scientific articles were rescued, 26 excluded by duplicity, 92 selected for full reading from the reading of their abstracts and 27 used in the construction of this review. Freeze-drying and glycerol conservation are similar methods, with glycerol conservation having greater economic advantage. The use of glycerol presents cytotoxicity when compared to the other methods. Cryopreservation keeps tissues viable, however, is more expensive and carry risks of transmission of pathogenic microorganisms. Overall, there is a lack of clarity about the importance of viability in the performance of skin grafts. Final considerations: the 3 methods have applicability in graft conservation. The lack of standardization in graft application despite its frequent application and the scarcity of recent studies on the subject justify the present study.

Reverse graft suturing to avoid Descemet’s membrane detachment of glycerol-preserved donor cornea used for therapeutic penetrating keratoplasty during COVID-19 to overcome the tissue shortage – A novel surgical technique

To overcome tissue shortage during pandemic, we switched to 100% glycerol preservation of the donor cornea, which is economical and provides longer duration of storage than the short and intermediate storage mediums we normally use like McCAREY Kaufman (MK) or cornisol. During our initial few cases of therapeutic penetrating keratoplasty using glycerol preserved donor cornea, we faced spontaneous Descemet’s detachments resistant to air tamponade. We tried reverse graft suturing and successfully reinforced Descemet’s attachment along with air tamponade, in one of the cases after multiple failed air injections. In the subsequent two cases of infective keratitis needing therapeutic penetrating Keratoplasty, we took eight reverse sutures in between the eight cardinals, to anchor the Descemet’s membrane of the graft. Both the grafts showed attached Descemet’s and maintained good graft clarity. The reverse corneal suturing technique has not been described to the best of our knowledge and hope this helps our corneal fraternity.

Effects of polyol excipient stability during storage and use on the quality of biopharmaceutical formulations / 药物分析学报

Biopharmaceuticals are formulated using a variety of excipients to maintain their storage stability.However,some excipients are prone to degradation during repeated use and/or improper storage,and the impurities generated by their degradation are easily overlooked by end users and are usually not strictly monitored,affecting the stability of biopharmaceuticals.In this study,we evaluated the degra-dation profile of polyol excipient glycerol during repeated use and improper storage and identified an unprecedented cyclic ketal impurity using gas chromatography with mass spectrometry(GC-MS).The other polyol excipient,mannitol,was much more stable than glycerol.The effects of degraded glycerol and mannitol on the stability of the model biopharmaceutical pentapeptide,thymopentin,were also evaluated.The thymopentin content was only 66.4％in the thymopentin formulations with degraded glycerol,compared to 95.8％in other formulations after the stress test.Most glycerol impurities(i.e.,aldehydes and ketones)reacted with thymopentin,affecting the stability of thymopentin formulations.In conclusion,this work suggests that more attention should be paid to the quality changes of excipients during repeated use and storage.Additional testing of excipient stability under real or accelerated conditions by manufacturers would help avoid unexpected and painful results.

Efficacy of a skin care ointment containing oligomeric maltose X in the adjuvant treatment of pruritus in patients with mild to moderate eczema: a multicenter, randomized, double-blind controlled clinical study / 中华皮肤科杂志

Objective:To evaluate the clinical efficacy and safety of a skin care ointment containing oligomeric maltose X in the adjuvant treatment of eczema-related pruritus.Methods:A multicenter, randomized, double-blind, vehicle-controlled clinical study was conducted. From March to September 2021, outpatients with mild to moderate eczema were collected from departments of dermatology of 4 hospitals, including Beijing Friendship Hospital, Hebei Traditional Chinese Medical Hospital, the Third People′s Hospital of Hubei Province, and Taizhou Central Hospital in Zhejiang Province. The patients were randomly divided into two groups by using a random number table: observation group topically treated with a skin care ointment containing oligomeric maltose X, and vehicle control group topically treated with an ointment vehicle. The ointments were applied during the attacks of itching for 14 consecutive days. Visits were scheduled before, 7, and 14 days after the start of the adjuvant treatment. The efficacy was evaluated according to the eczema area and severity index (EASI) and visual analog scale (VAS) , and adverse events were recorded. The efficacy and safety analyses were conducted by using chi-square test and t test. Results:Totally, 232 patients with eczema were enrolled, including 90 males and 142 females, with the age being 40.13 ± 13.36 years; 156 patients were in the observation group, and 76 in the vehicle control group. Before the adjuvant treatment, there were no significant differences in EASI (2.07 ± 2.24 points vs. 2.29 ± 2.28 points) or VAS (6.22 ± 1.78 points vs. 6.20 ± 1.79 points) scores between the observation group and vehicle control group ( t = -0.70, 0.06, P = 0.486, 0.955, respectively) . After one-day treatment, the VAS scores significantly decreased compared with the baseline scores in the two groups ( P < 0.001, P = 0.003, respectively) . After 14-day treatment, the VAS score was significantly lower in the observation group (2.67 points) than in the vehicle control group (3.35 points; t = -2.28, P = 0.024) . After 7- and 14-day treatment, the EASI scores significantly decreased compared with the baseline scores in both the two groups (all P < 0.001) , but there were no significant differences between the two groups ( P = 0.853, 0.731) . No adjuvant treatment-related adverse events were recorded in either of the two groups. Conclusion:The skin care ointment containing oligomeric maltose X is safe and effective in the adjuvant treatment of eczema-related pruritus, and can be applied to clinical practice.

Uma revisão sobre: tratamento biológico de drenagem de mina — cenário atualizado, perspectivas e recomendações de futuros trabalhos / Biological treatment of mine drainage — scenario updated, perspectives, and recommendations for future works

RESUMO Rochas contendo sulfetos metálicos podem ser oxidadas em um processo catalisado por procariotos quimiolitoautotróficos ou Fe3+. A atividade mineradora acelera esse processo ao gerar resíduos contendo sulfetos metálicos com grande superfície de contato. O lixiviado resultante, conhecido como drenagem de mina (DM), é rico em sulfato, íons hidrogênio e contaminantes químicos inorgânicos como ferro (Fe), zinco (Zn), cádmio (Cd), manganês (Mn), níquel (Ni), arsênio (As) e alumínio (Al). Para remover tais poluentes, atualmente, o principal tratamento utilizado é a adição de reagentes alcalinos. Entretanto, esse método tem limitada eficiência, alto custo e gera grandes volumes de resíduos sólidos tóxicos de relativa solubilidade. Bactérias redutoras de sulfato (BRS) podem oxidar matéria orgânica com geração de sulfeto. Algumas vias metabólicas do processo consomem H+neutralizando o pH. O sulfeto produzido pode reagir com contaminantes inorgânicos e precipitá-los, permitindo sua recuperação da fase líquida. O uso de subprodutos industriais e urbanos contendo diferentes fontes de carbono como doadores de elétrons no tratamento de DM tem sido investigado. Este artigo sumariza dados sobre as variáveis relevantes para a atividade microbiana durante o tratamento biológico de DM, analisando o atual cenário de pesquisas com fontes alternativas de carbono. Discute-se ainda novas fontes de matéria orgânica ainda não aplicadas para tratamento biológico de efluentes e que, sob aspectos de sustentabilidade, dos pontos de vista sustentável e econômico, podem ser usadas no tratamento de resíduos.

ABSTRACT Rocks containing metal sulfides be can oxidized biologically or chemically. Chemolithoautotrophics prokaryotes and Fe3+ catalyze this process. The mining activities also accelerate the process for creates metal sulphides tailings with a big contact surface. The leached formed is called Mine Drainage (MD) whose composition is rich in sulphate, hydrogen ions and inorganic chemical contaminants such as Fe, Zn, Mn, Cd, Ni, As e Al. Currently, in order to remove these pollutants, the main treatment used is the addition of alkaline reagents. However, the method has limited efficiency, high cost with input reagents and generates wide amounts of toxic solid residues with high solubility. The sulphide reducing bacterias (RSB) can oxidize organic matter generating sulphide. Some metabolic pathways consume H+ neutralizing the pH. The sulphide formed can react and precipitate inorganic pollutants, allowing their recuperation from the liquid phase. The use of industrial and urban by-products containing different carbon sources have been investigated as an electron donor in the MD treatment. The diverse microbial consortia synergic acting can present bigger efficiency in the presence of mixed carbon sources, besides lower cost in relation to the pure matter. Here will be detailed the biological treatment about which and how the variables of the system can influence the microbial activity and relevant molecules to the treatment. After is described the current situation of the research about alternative carbon sources. New carbon sources whose are a by-product of the expanding industry presenting good feature to anaerobic degrading are suggested. The by-product potential is described from the point of view of sustainability, and waste management.

Changes in freshwater sediment microbial populations during fermentation of crude glycerol

BACKGROUND: This work studied how the exposure to an unusual substrate forced a change in microbial populations during anaerobic fermentation of crude glycerol, a by-product of biodiesel production, with freshwater sediment used as an inoculum. RESULTS: The microbial associations almost completely (99.9%) utilized the glycerol contained in crude glycerol 6 g L 1 within four days, releasing gases, organic acids (acetic, butyric) and alcohols (ethanol, n-butanol) under anaerobic conditions. In comparison with control medium without glycerol, adding crude glycerol to the medium increased the amount of ethanol and n-butanol production and it was not significantly affected by incubation temperature (28 C or 37 C), nor incubation time (4 or 8 d), but it resulted in reduced amount of butyric acid. Higher volume of gas was produced at 37 C despite the fact that the overall bacterial count was smaller than the one measured at 20 C. Main microbial phyla of the inoculum were Actinobacteria, Proteobacteria and Firmicutes. During fermentation, significant changes were observed and Firmicutes, especially Clostridium spp., began to dominate, and the number of Actinobacteria and Gammaproteobacteria decreased accordingly. Concentration of Archaea decreased, especially in medium with crude glycerol. These changes were confirmed both by culturing and culture-independent (concentration of 16S rDNA) methods. CONCLUSIONS: Crude glycerol led to the adaptation of freshwater sediment microbial populations to this substrate. Changes of microbial community were a result of a community adaptation to a new source of carbon.

Effects of glycerol and sodium pentaborate containing new formulation on sleeve gastrectomy model in rats

ABSTRACT Purpose: The development of cutting surface leakage and postoperative peritoneal adhesions (PPA) after sleeve gastrectomy (SG) are the most serious operative complications. We investigated the effectiveness of the newly developed glycerol and sodium pentaborate containing formulation on the prevention of these complications. Methods: Sixteen Sprague Dawley rats (mean weight 310 ± 50 g, mean age 3 months old) were divided into two groups, consisting of eight rats in each. SG and a double-layer suture technique were performed for each group. In study group, there was the mixture of 2 mL 3% glycerol plus 3% sodium pentaborate formulation, and in the control group 2 mL 0.9% NaCl was injected into the peritoneal cavity. Rats were sacrificed after 30 days, then macroscopic adhesion grade scoring and histopathological evaluations were assessed. Results: Macroscopic PPA scores in the control and study groups were 2.75 ± 0.16 and 1.50 ± 0.327, respectively (p = 0.004). Histopatologic fibrosis scores in the control and study groups were 0.87 ± 0.125 and 2.00 ± 0.26, respectively (p = 0.002). Conclusions: In SG operation model, glycerol plus sodium pentaborate compound decreased PPA formation and also increased stomach cut surface line fibrosis. This new formulation is hopeful for more safe SG operations.

Tea grape reduces abdominal aortic occlusion-induced lung injury

Abstract Introduction: Ischemia-associated mortality caused by aortic cross-clamps, as in ruptured abdominal aorta aneurysm surgeries, and reperfusion following their removal represent some of the main emergency conditions in cardiovascular surgery. The purpose of our study was to examine the potential protective effect of tea grape against aortic occlusion-induced lung injury using biochemical, histopathological, immunohistochemical, and quantitative analyses. Methods: Thirty-two male Sprague-Dawley rats were randomly assigned into four groups: control (healthy), glycerol + ischemia/reperfusion (I/R) (sham), I/R, and I/R + tea grape. Results: Following aortic occlusion, we observed apoptotic pneumocytes, thickening in the alveolar wall, edematous areas in interstitial regions, and vascular congestion. We also observed an increase in pulmonary malondialdehyde (MDA) levels and decrease in pulmonary glutathione (GSH). However, tea grape reduced apoptotic pneumocytes, edema, vascular congestion, and MDA levels, while increased GSH levels in lung tissue. Conclusion: Our findings suggest that tea grape is effective against aortic occlusion-induced lung injury by reducing oxidative stress and apoptosis.

Development of resin-based bioactive endodontic cements with glycerol salicylate and calcium silicate / Desenvolvimento de cimentos endodônticos bioativos à base de resina com salicilato de glicerol e silicato de cálcio

Introduction: The combination of sol-gel derived calcium silicate particles and glycerol salicylate resins may enhance the pyhisico-chemical properties contribute to the unders-tanding of the interaction between these materials. This study aims to evaluate the physical-chemical properties of resin-based bioactive endodontic cements with glycerol salicylate resins and calcium silicate particles. Materials and methods: Calcium silicate was produced by the sol-gel route, while the resin was produced by mixing 60wt% glycerol salicylate, 30wt% methyl salicylate and 10wt% distilled water. Calcium silicate was added in three different concentrations, 50, 40 and 25% by weight. The cement was tested for setting time, flow, radiopacity and pH. Results: The 50:50 group shows the time of 15min8s while the 75:25 shows the time of 256min13s (p < 0.05). The 50:50 group has a lower flow (15.156mm) compared to 60:40 (23.588 mm) and 75:25 (25.396 mm). All radiopacity values were below 3mmAl. All groups showed a pH increase up to 24 hours and the pH value drop was inversely proportional to the amount of calcium silicate. Discussion: Bioactive calcium silicate particles were used in a composite material with a glycerol salicylate resin. Among the tested cements, the combination of 50wt% calcium silicate particles to 50wt% glycerol salicylate resin showed adequate setting time and promoted an increase in water pH. Conclusion: The 50:50 group showed the setting time and the pH, showing that these materials may be able to promote enhanced biological response. The adjustment of flow and radiopacity should be considered for its clinical application.

Introdução: A combinação entre partículas de silicato de cálcio e glycerol salicilato tem potencial para melhorar as propriedades físico-químicas de cimentos endodônticos bioativos. O objetivo deste estudo foi avaliar as propriedades físico-químicas de cimentos resinosos contendo glicerol salicilato e silicatos de cálcio. Materiais e métodos: O silicato de cálcio foi produzido pelo método sol-gel, en-quanto o líquido foi obtido pela mistura de 60% de salicilato de glicerol, 30% de salicilato de metila e 10% de água destilada em peso. O silicato de cálcio foi adicionado em três diferentes concentrações, sendo elas 50, 40 e 25% em peso. O cimento foi testado em relação ao tempo de presa, escoamento, radiopacidade e pH. Resultados: O grupo 50:50 apresentou tempo de presa de 15min8s enquanto o 75:25 apresentou um tempo de 256min13s (p < 0,05). O grupo 50:50 apresentou menor escoamento (15,156mm) em comparação ao 60:40 (23,588mm) e 75:25 (25,396mm). Quanto à radiopacidade, todos obtiveram valores menores que 3mmAl. Todos apresentaram aumento de pH até 24h, e após esse período tiveram quedas inversamente proporcionais a quantidade de silicato de cálcio em cada um. Discussão: Partículas bioativas de silicato de cálcio foram utilizadas em um compósito com base resi-nosa de glicerol salicilato. Dentre os cimentos utilizados, a combinação de 50:50 entre os componentes tem resultados promissores para a aplicação destes materiais. Conclusão: O grupo 50:50 apresentou adequado tempo de presa e pH, indicando que o material pode manter suas propriedades biológicas. A radiopacidade e o escoamento, no entando, devem ser adequadas para aplicação do material.

Enhanced pyruvic acid yield in an osmotic stress-resistant mutant of Yarrowia lipolytica

BACKGROUND: Pyruvic acid (PA), a vital α-oxocarboxylic acid, plays an important role in energy and carbon metabolism. The oleaginous yeast Yarrowia lipolytica (Y. lipolytica) has considerable potential for the production of PA. An increased NaCl concentration reportedly increases the biomass and PA yield of Y. lipolytica. RESULTS: To increase the yield of PA, the NaCl-tolerant Y. lipolytica A4 mutant was produced using the atmospheric and room temperature plasma method of mutation. The A4 mutant showed growth on medium containing 160 g/L NaCl. The PA yield of the A4 mutant reached 97.2 g/L at 120 h (0.795 g/g glycerol) in a 20-L fermenter with glycerol as the sole carbon source, which was 28.9% higher than that of the parental strain. CONCLUSION: The PA yield from Y. lipolytica can be improved by increasing its NaCl tolerance.

Perfil de ácidos graxos do leite de vacas Holandês x Gir alimentadas com silagem de milho e concentrado contendo ou não glicerina bruta / Milk fatty acid profile from Holstein x Gyr cows fed corn silage and concentrate containing or not crude glycerin

O objetivo deste estudo foi avaliar o perfil de ácidos graxos (AG) do leite de vacas alimentadas com dietas à base de silagem de milho contendo 0% e 8,9% de glicerina bruta (GB) na matéria seca (MS). Foram utilizadas 18 vacas Holandês x Gir com 48±18 dias em lactação, produzindo 19,8±4,9kg/dia de leite. Utilizou-se delineamento de blocos ao acaso, com nove vacas/tratamento e duas medidas repetidas no tempo, com os resultados analisados por modelos mistos. A inclusão de GB na dieta não alterou a ingestão de MS, mas reduziu os consumos dos AG oleico, linoleico e α-linolênico. Os teores dos AG mirístico, palmítico, rumênico, vacênico, esteárico, oleico, linoleico, α-linolênico e CLA trans-10 cis-12 na gordura do leite foram semelhantes entre dietas. A inclusão de GB reduziu os teores dos AG elaídico e C18:1 trans-10 e aumentou os teores dos AG de cadeia ímpar linear e do ácido láurico. Não houve efeito da inclusão da GB sobre os índices de aterogenicidade e trombogenicidade da gordura do leite. Concluiu-se que a inclusão de glicerina bruta em dieta à base de silagem de milho não afetou a qualidade nutricional da gordura do leite de vacas Holandês x Gir.(AU)

The objective of this study was to evaluate the milk fatty acid (FA) composition of cows fed corn silage-based diets containing 0% and 8.9% of crude glycerin (GB) on a dry matter (DM) basis. Eighteen Holstein x Gyr cows with 48±18 days in milk and producing 19.8±4.9kg milk/day were used in the study. The experimental design was a randomized block with nine cows per treatment and two repeated measures. Results were analyzed using mixed models. The milk fat contents of myristic, palmitic, rumenic, vaccenic, estearic, oleic, linoleic, α-linolenic, and trans-10 cis-12 CLA were similar between diets. Dietary inclusion of GB decreased elaidic and trans-10 C18:1, and increased lauric acid and odd linear-chain FA contents in milk fat. Both atherogenicity and trombogenicity indices were unaffected by GB inclusion. It was concluded that GB inclusion in corn silage-based diets had no effect on the nutritional quality of milk fat from Holstein x Gyr dairy cows.(AU)

Synthesis of poly(glycerol sebacate) and its research hotspots / 中国组织工程研究

BACKGROUND: Poly(glycerol sebacate) holds excellent and good biocompatibility, flexibility and degradability, which is widely used in soft tissue replacement and tissue engineering, drug delivery carrier, wound dressing, and bone-cartilage regeneration. OBJECTIVE: To summarize the research progress in the optimal synthesis and medical application of poly(glycerol sebacate) and its composites. METHODS: PubMed, Elsevier, CNKI and WanFang databases were retrieved. The key words were “poly(glycerol sebacate), synthesis, cardiac muscle, blood vessels, nerves, skin, drug delivery carrier, wound dressing, bone regeneration” in English and Chinese, respectively. Finally, 43 articles eligible for the inclusion criteria were obtained. RESULTS AND CONCLUSION: In recent years, poly(glycerol sebacate) has attracted much attention because of its many excellent properties. Many basic scientific studies and animal experiments have confirmed that it is suitable for tissue engineering. Conventional poly(glycerol sebacate) curing process requires high temperature, high vacuum and long duration, which prevents the polymer from binding directly to cells or temperature-sensitive molecules, resulting in some limitations in its application. The composite scaffold material synthesized with a variety of other materials can make up for the corresponding shortcomings of its application in myocardial and vascular tissue engineering, drug delivery carrier, nerve guiding materials, skin and wound dressing, and bone-cartilage tissue engineering. At present, most of the studies on poly(glycerol sebacate) composites focus on the cytobiology level, and few studies focus on the mechanism of action in vivo. Further study may develop an important material for tissue replacement.

Progress in metabolic engineering of biosynthesis of 3-hydroxypropionic acid / 生物工程学报

As an important platform compound, 3-hydroxypropionic acid (3-HP) can be used as a substrate to synthesize a variety of biological products with commercial potential. The titer of 3-HP by wild-type bacteria is low, which severely limits the large-scale application and production of 3-HP. By modifying the genes related to the metabolic pathway, engineered bacteria using cheap substrates as carbon sources are constructed, the aim of reducing production cost and increasing output is realized. In this paper, the recent progress in the synthesis of 3-HP by metabolic engineering at home and abroad is reviewed. The advantages and disadvantages of glycerol pathway, malonyl-CoA pathway and beta-alanine pathway for synthesis of 3-HP are also summarized and analyzed, and the future development of 3-HP is prospected.

3--Acetyl-11-keto- -boswellic acid ameliorated aberrant metabolic landscape and inhibited autophagy in glioblastoma

Glioblastoma is the most common and aggressive primary tumor in the central nervous system, accounting for 12%-15% of all brain tumors. 3--Acetyl-11-keto--boswellic acid (AKBA), one of the most active ingredients of gum resin from Birdw., was reported to inhibit the growth of glioblastoma cells and subcutaneous glioblastoma. However, whether AKBA has antitumor effects on orthotopic glioblastoma and the underlying mechanisms are still unclear. An orthotopic mouse model was used to evaluate the anti-glioblastoma effects of AKBA. The effects of AKBA on tumor growth were evaluated using MRI. The effects on the alteration of metabolic landscape were detected by MALDI-MSI. The underlying mechanisms of autophagy reducing by AKBA treatment were determined by immunoblotting and immunofluorescence, respectively. Transmission electron microscope was used to check morphology of cells treated by AKBA. Our results showed that AKBA (100 mg/kg) significantly inhibited the growth of orthotopic U87-MG gliomas. Results from MALDI-MSI showed that AKBA improved the metabolic profile of mice with glioblastoma, while immunoblot assays revealed that AKBA suppressed the expression of ATG5, p62, LC3B, p-ERK/ERK, and P53, and increased the ratio of p-mTOR/mTOR. Taken together, these results suggested that the antitumor effects of AKBA were related to the normalization of aberrant metabolism in the glioblastoma and the inhibition of autophagy. AKBA could be a promising chemotherapy drug for glioblastoma.

Effects of aerosolized glycerol on human lung epithelial cells by air-liquid interface cloud exposure / 中国药理学通报

Aim To investigate the cytotoxicity of glycerol aerosol on human lung adenocarcinoma cells (A549) by air-liquid interface exposure, aimingto provide a guidance for the application of glycerol in inhalation products and e-cigarettes. Methods A549 cells cultured at air-liquid interface condition were exposed by VITROCELL cloud exposure system. Firstly, the delivery efficiency of the system was verified by fluorescein sodium, and repeatability and difference between inserts were investigated. Then, a glycerol aerosol airliquid interface exposure test was performed, and a negative control (1% PBS) and high, medium, and low dose of glycerol(10%, 6%, and 4%) were set to examine the cell viability, LDH release, as well as the expression of IL-6. Results The exposure system delivered an accurate dose. The delivery efficiency was high, the deposition rate was 53. 4%, and the characteristic parameters such as repeatability was 14. 8% and insert-insert difference was 5. 2%. After exposure to aerosolized glycerol, there was no significant difference in cell variability, LDH release, and IL-6 expression of A549 cells compared to the negative control. Conclusions A reliable and rapid in vitro model of acute exposure model of the respiratory tract is established. A single short-term exposure to aerosolized glycerol has no significant effect on cell viability and cytotoxicity, as well as inflammatory changes.

Conversion of renewable substrates for biosurfactant production by Rhizopus arrhizus UCP 1607 and enhancing the removal of diesel oil from marine soil

BACKGROUND: The use of agro-industrial wastes to produce high value-added biomolecules such as biosurfactants is a promising approach for lowering the total costs of production. This study aimed to produce biosurfactants using Rhizopus arrhizus UCP 1607, with crude glycerol (CG) and corn steep liquor (CSL) as substrates. In addition, the biomolecule was characterized, and its efficiency in removing petroderivatives from marine soil was investigated. RESULTS: A 22 factorial design was applied, and the best condition for producing the biosurfactant was determined in assay 4 (3% CG and 5% CSL). The biosurfactant reduced the surface tension of water from 72 to 28.8 mN/m and produced a yield of 1.74 g/L. The preliminary biochemical characterization showed that the biosurfactant consisted of proteins (38.0%), carbohydrates (35.4%), and lipids (5.5%). The compounds presented an anionic character, nontoxicity, and great stability for all conditions tested. The biomolecule displayed great ability in dispersing hydrophobic substrates in water, thereby resulting in 53.4 cm2 ODA. The best efficiency of the biosurfactant in removing the pollutant diesel oil from marine soil was 79.4%. CONCLUSIONS: This study demonstrated the ability of R. arrhizus UCP1607 to produce a low-cost biosurfactant characterized as a glycoprotein and its potential use in the bioremediation of the hydrophobic diesel oil pollutant in marine soil