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1.
Water Sci Technol ; 82(6): 1237-1246, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-33055413

RESUMO

This study focused on the simultaneous recovery of carbohydrates (CHO) and phosphorus (P) from Desmodesmus sp. biomass cultivated in municipal wastewater, through a sequential pretreatment. The pretreatment consisted first of ultrasound to trigger cell disruption followed by ozonation to recover CHO and P. For ozone pretreatment, three different parameters were considered: ozone concentration (9, 15, 21, 27, 36, and 45 mg O3/L), contact time (15, 25 and 35 min), and pH (8 and 11). The maximum simultaneous release of 84% of CHO and 58% of P was achieved at the experimental parameters of ozone concentration of 45 mg O3/L, contact time of 35 min, and pH of 11. Also, P was concentrated in solution by 8- to 14-fold with respect to municipal wastewater. The sequential pretreatment was conducted at alkaline pH of 11 and atmospheric conditions, which may considerably reduce energy demand and reagents, in comparison to a traditional hydrolysis pretreatment. The results found suggest that the sequential pretreatment could be feasible on a large scale.


Assuntos
Ozônio , Águas Residuárias , Biomassa , Carboidratos , Fósforo
2.
Nat Commun ; 11(1): 4874, 2020 09 25.
Artigo em Inglês | MEDLINE | ID: mdl-32978395

RESUMO

Organic synthesis methodology enables the synthesis of complex molecules and materials used in all fields of science and technology and represents a vast body of accumulated knowledge optimally suited for deep learning. While most organic reactions involve distinct functional groups and can readily be learned by deep learning models and chemists alike, regio- and stereoselective transformations are more challenging because their outcome also depends on functional group surroundings. Here, we challenge the Molecular Transformer model to predict reactions on carbohydrates where regio- and stereoselectivity are notoriously difficult to predict. We show that transfer learning of the general patent reaction model with a small set of carbohydrate reactions produces a specialized model returning predictions for carbohydrate reactions with remarkable accuracy. We validate these predictions experimentally with the synthesis of a lipid-linked oligosaccharide involving regioselective protections and stereoselective glycosylations. The transfer learning approach should be applicable to any reaction class of interest.


Assuntos
Carboidratos/química , Aprendizado de Máquina , Oligossacarídeos/química , Metabolismo dos Carboidratos , Técnicas de Química Sintética , Glicosilação , Estrutura Molecular , Oligossacarídeos/metabolismo
3.
Bioresour Technol ; 316: 123883, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32739575

RESUMO

This study aimed to evaluate the growth and production of biomolecules by Spirulina sp. LEB 18 cultivated in seawater. The seawater was used without nutrient addition (SW0) and supplemented with 100% (SW100), 50% (SW50), and 25% (SW25) nitrogen, phosphorus, iron, and EDTA concentrations that make up the Zarrouk culture medium. When grown in SW0, Spirulina sp. LEB 18 showed maximum biomass concentration (2.17 g L-1) on the 11th d of cultivation and an increase in the carbohydrate content and productivity by 203% and 52%, respectively, when compared to the control culture. This cultivation strategy demonstrated the feasibility of using seawater as an alternative to freshwater in cultures as well as reduced nutritional requirements for biomass and carbohydrate production.


Assuntos
Microalgas , Spirulina , Biomassa , Carboidratos , Nutrientes , Água do Mar
5.
Wiad Lek ; 73(7): 1373-1376, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32759423

RESUMO

OBJECTIVE: The aim: To assess carbohydrate and lipid metabolic profiles of tuberculosis patients with bilateral injuries of the lungs and mycobacteria excretion. PATIENTS AND METHODS: Materials and methods: Seventy two newly diagnosed pulmonary TB patients were examined. Group I - 17 newly diagnosed TB patients who had unilateral pulmonary lesions and had no mycobacteria excretion. Group II - 55 newly diagnosed TB patients who had bilateral pulmonary lesions and mycobacteria excretion. The control group included 20 healthy persons. Fasting insulin level, indices of lipidogram were measured, oral glucose tolerance test was performed. Statistical processing of the obtained results was carried out by analyzing the contingency tables using the StatisticaBasicAcademic 13 for Windows software package. RESULTS: Results: Tuberculosis patients develop insulin resistance - condition that is a precursor to developing type 2 diabetes and metabolic disorder of lipid exchange - dyslipidemia. Patients with bilateral pulmonary lesions and mycobacteria excretion have the most pronounced disorders of carbohydrate and lipid metabolism compared to patients with limited lesions of the lungs. CONCLUSION: Conclusions: We suppose that mycobacteria excretion and bilateral lesions of lungs may be the markers of the degree of carbohydrate and lipid metabolism disorders in patients with pulmonary tuberculosis.


Assuntos
Tuberculose , Carboidratos , Diabetes Mellitus Tipo 2 , Humanos , Metabolismo dos Lipídeos , Lipídeos , Metaboloma
6.
Nat Methods ; 17(7): 651, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32616923
8.
PLoS One ; 15(7): e0235975, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32649704

RESUMO

Rice cultivar "Weiyou916" (Oryza sativa L. ssp. Indica) were cultured with control (10 mM NO3-) and nitrate deficient solution (0 mM NO3-) for four weeks. Nitrogen (N) deficiency significantly decreased the content of N and P, dry weight (DW) of the shoots and roots, but increased the ratio of root to shoot in O. sativa. N deficiency decreased the photosynthesis rate and the maximum quantum yield of primary photochemistry (Fv/Fm), however, increased the intercellular CO2 concentration and primary fluorescence (Fo). N deficiency significantly increased the production of H2O2 and membrane lipid peroxidation revealed as increased MDA content in O. sativa leaves. N deficiency significantly increased the contents of starch, sucrose, fructose, and malate, but did not change that of glucose and total soluble protein in O. sativa leaves. The accumulated carbohydrates and H2O2 might further accelerate biosynthesis of lignin in O. sativa leaves under N limitation. A total of 1635 genes showed differential expression in response to N deficiency revealed by Illumina sequencing. Gene Ontology (GO) analysis showed that 195 DEGs were found to highly enrich in nine GO terms. Most of DEGs involved in photosynthesis, biosynthesis of ethylene and gibberellins were downregulated, whereas most of DEGs involved in cellular transport, lignin biosynthesis and flavonoid metabolism were upregulated by N deficiency in O. sativa leaves. Results of real-time quantitative PCR (RT-qPCR) further verified the RNA-Seq data. For the first time, DEGs involved oxygen-evolving complex, phosphorus response and lignin biosynthesis were identified in rice leaves. Our RNA-Seq data provided a global view of transcriptomic profile of principal processes implicated in the adaptation of N deficiency in O. sativa and shed light on the candidate direction in rice breeding for green and sustainable agriculture.


Assuntos
Flavonoides/metabolismo , Lignina/metabolismo , Nitratos/metabolismo , Oryza/genética , Fotossíntese , Carboidratos/análise , Clorofila A/química , Regulação da Expressão Gênica de Plantas , Peróxido de Hidrogênio/metabolismo , Malondialdeído/metabolismo , Oryza/metabolismo , Oxirredução , Folhas de Planta/genética , Folhas de Planta/metabolismo , Raízes de Plantas/metabolismo , Brotos de Planta/metabolismo , RNA de Plantas/química , RNA de Plantas/metabolismo , Análise de Sequência de RNA
9.
Ying Yong Sheng Tai Xue Bao ; 31(4): 1378-1388, 2020 Apr.
Artigo em Chinês | MEDLINE | ID: mdl-32530214

RESUMO

Non-structural carbohydrates (NSC) are essential substances for the tree growth and metabolism, and play an important role in environmental adaptation of trees. At temporal scale, NSC contents in trees have limited inter-annual variation, which could be attributed to the strategy of tree growth and carbon storage. Different factors influence NSC contents of trees in various climatic regions, which change substantially at the seasonal scale. At spatial scale, the variations of NSC content in trees show an insignificantly decreasing trend with the decreases of latitude at global and continental scales, which are mainly related to the hydrothermal gradients. The trend at regional scale is opposite because of the decrease of hydrothermal gradients and lower sample frequency. More sophisticated relations exist between the variations of NSC content in trees and altitudes, which are caused by species-specific characteristics and the variations of micro-habitat conditions. The variations of NSC content in trees at multiple spatial-temporal scales are generally determined by both biotic and abiotic factors, which are mainly dependent on the tradeoff among photosynthate production, respiratory depletion, and tree growth. Furthermore, the methods used for the determination of NSC content are different, which results in great uncertainties in comparing conclusions from different studies. The methods used for sample collection and measurement of NSC should be improved and unified to enhance the comparison among different studies. The NSC contents of trees in different age classes should be measured with all organs collected at multiple spatial-temporal scales. The underlying mechanisms, significance of NSC storage, transformation and allocation on tree growth and survival should be further discussed.


Assuntos
Metabolismo dos Carboidratos , Árvores , Carboidratos , Carbono , Estações do Ano
10.
Waste Manag ; 112: 40-51, 2020 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-32497900

RESUMO

Black soldier fly larvae treatment is an emerging technology for the conversion of biowaste into potentially more sustainable and marketable high-value products, according to circular economy principles. Unknown or variable performance for different biowastes is currently one challenge that prohibits the global technology up-scaling. This study describes simulated midgut digestion for black soldier fly larvae to estimate biowaste conversion performance. Before simulation, the unknown biowaste residence time in the three midgut regions was determined on three diets varying in protein and non-fiber carbohydrate content. For the static in vitro model, diet residence times of 15 min, 45 min, and 90 min were used for the anterior, middle, and posterior midgut region, respectively. The model was validated by comparing the ranking of diets based on in vitro digestion products to the ranking found in in vivo feeding experiments. Four artificial diets and five biowastes were digested using the model, and diet digestibility and supernatant nutrient contents were determined. This approach was able to distinguish broadly the worst and best performing rearing diets. However, for some of the diets, the performance estimated based on in vitro results did not match with the results of the feeding experiments. Future studies should try to establish a stronger correlation by considering fly larvae nutrient requirements, hemicellulose digestion, and the diet/gut microbiota. In vitro digestion models could be a powerful tool for academia and industry to increase conversion performance of biowastes with black soldier fly larvae.


Assuntos
Dípteros , Simuliidae , Animais , Carboidratos , Cor , Dieta , Larva
12.
Artigo em Inglês | MEDLINE | ID: mdl-32485615

RESUMO

COMBINING HYDRAULIC: and carbon-related measurements can help elucidate drought-induced plant mortality. To study drought mortality mechanisms, seedlings of two woody species, including the anisohydric Robinia pseudoacacia and isohydric Quercus acutissima, were cultivated in a greenhouse and subjected to intense drought by withholding water and mild drought by adding half of the amount of daily water lost. Patterns of leaf and root gas exchange, leaf surface areas, growth, leaf and stem hydraulics, and carbohydrate dynamics were determined in drought-stressed and control seedlings. We detected a complete loss of hydraulic conductivity and partial depletion of total nonstructural carbohydrates contents (TNC) in the dead seedlings. We also found that intense drought triggered a more rapid decrease in plant water potential and a faster drop in net photosynthesis below zero, and a greater TNC loss in dead seedlings than mild drought. Additionally, anisohydric R. pseudoacacia suffered a rapider death than the isohydric Q. acutissima. Based on these findings, we propose that hydraulic conductivity loss and carbon limitation jointly contributed to drought-induced death, while the relative contributions could be altered by drought intensity. We thus believe that it is important to illustrate the mechanistic relationships between stress intensity and carbon-hydraulics coupling in the context of isohydric vs. anisohydric hydraulic strategies.


Assuntos
Carboidratos/análise , Secas , Quercus/fisiologia , Plântula/fisiologia , Água/fisiologia , Folhas de Planta
13.
Anim Sci J ; 91(1): e13403, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32557958

RESUMO

The effects of inclusion of persimmon peel (PP) in total mixed ration (TMR) silage on its nutrient composition, tannin content, and in vitro ruminal fermentation were studied. Four types of TMR silages containing 0, 50, 100, and 150 g/kg of PP on a dry matter basis were prepared. The dietary contents of non-fiber carbohydrate (NFC) decreased, while soluble protein fraction increased after ensiling of the TMR. In the TMR silages, the content of insoluble tannin increased (p < .05) with increasing PP level. The fraction of soluble protein decreased linearly (p < .01), while that of neutral detergent insoluble protein increased linearly (p < .01) with increasing the PP level in the TMR silages. The total gas and methane yields from the in vitro rumen fermentation of the TMR silages were lower (p < .01) than those of pre-ensiled TMR and declined linearly (p < .01) with increasing PP level. These results indicate that adding PP to TMR silage may resist the breakdown of dietary protein during the ensiling process, although the ruminal fermentability of TMR possibly decreased after ensiling due to the loss of NFC.


Assuntos
Diospyros , Fermentação , Rúmen/fisiologia , Silagem/análise , Taninos/análise , Animais , Biocombustíveis/análise , Carboidratos/análise , Proteínas na Dieta/análise , Técnicas In Vitro , Metano/análise , Solubilidade
15.
Bioresour Technol ; 312: 123566, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32504949

RESUMO

The anaerobic co-digestion (AcoD) of FWs produces variable methane yields, mainly due to variable carbon/nitrogen (C/N) ratio and proportions of lipids (L), carbohydrates (C), and proteins (P) in different FW samples. In this study, a significant interaction between C/N ratio and LCP composition was found and contributed to the differing trends between special (SMP) and theoretical methane production. The highest SMP of 595 mL CH4 gVS-1 occurred at C/N of 25 and LCP of 63.25:22.62:14.13, followed by 592 mL CH4 gVS-1 at C/N of 30 and LCP of 48.94:39.74:11.32, which also reflected their interaction. Attributing to their interactive effect on obtaining optimal process parameters and microbial community, the inhibition threshold of lipid as well as the methane yield was increased. Understanding the interaction between C/N ratio and LCP composition is an effective and promising way to obtain suitable mixture ratios of organic wastes under AcoD.


Assuntos
Biocombustíveis , Eliminação de Resíduos , Anaerobiose , Reatores Biológicos , Carboidratos , Carbono , Alimentos , Lipídeos , Metano , Nitrogênio
16.
Bioresour Technol ; 314: 123723, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32599527

RESUMO

Pretreatment is an essential upstream process to deconstruct oil palm empty fruit bunch fiber (OPEFBF) prior to sugars production. This study aimed to investigate the efficiency of OPEFBF pretreatment using palm oil mill effluent (POME) as solvent. The effect of alkali catalyst (5%w/w NaOH and ammonia), temperature (90,120,135 °C) and time (60,120,180 min) on the efficiency of pretreatment (OPEFBF-to-solvent ratio of 1:25) was also investigated. The results indicated that POME-pretreatment (135 °C, 180 min) enhanced glucose yield by only ~56%. Glucose production was increased about 5.8-fold to 495.3 ± 5.9 mg g-1 OPEFBF when NaOH was added in POME-pretreatment (Na-P). The xylose production from OPEFBF was increased about 3.7-fold after ammonia-catalyzed POME-pretreatment. About 12.1 ± 0.2 g L-1 of ethanol was produced from Na-P-hydrolysate at molar conversion of 59.4 ± 1.4%. This research provides new insight into the use of POME as a cost-effective pretreatment solvent of OPEFBF to reduce upstream process cost by cutting down water usage.


Assuntos
Frutas , Açúcares , Carboidratos , Óleo de Palmeira , Óleos Vegetais , Solventes
17.
Stud Health Technol Inform ; 270: 693-697, 2020 06 16.
Artigo em Inglês | MEDLINE | ID: mdl-32570472

RESUMO

Patients with diabetes are often worried about having low blood glucose because of the unpleasant feeling and possible dangerous situations this can lead to. This can make patients consume more carbohydrates than necessary. Ad-hoc carbohydrate estimation and dosing by the patients can be unreliable and may produce unwanted periods of high blood glucose. In this paper we present a system that automatically estimates and dispenses the amount of juice (or similar) according to the current patients' blood glucose values. The system is remotely accessible and customizable from a chatbot, exploits sensors and actuators to dispense the necessary amount of liquid carbohydrates. It relies on a cloud solution (Nightscout) to acquire the patient's blood glucose values, which are constantly updated thanks to a commercial wearable continuous glucose monitor (CGM).


Assuntos
Diabetes Mellitus , Hipoglicemia , Glicemia , Automonitorização da Glicemia , Carboidratos , Humanos , Hipoglicemiantes , Sistemas de Infusão de Insulina
18.
Bioresour Technol ; 311: 123568, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32467028

RESUMO

This review presents an emerging biorefinery platform for C2-5 bioalcohol production through chemical synthesis using the organic waste materials. Bioalcohols are the most commercialized carbon-neutral transportation fuels, compatible with existing an internal combustion (IC) engine. However, current bioalcohol fermentation processes have made from sugar-rich edible crops. Also, carbon loss from the fermentation process is substantial. To minimize carbon loss, volatile fatty acids (VFAs) can be utilized as a raw material for bioalcohol production. Thus, a two-step chemical upgrading of VFAs into C2-5 alcohols is summarized in comparison with current challenges of biological fermentation processes for bioalcohol production. This review also provides the prospect of the hybrid biological/chemical process, presenting the technical advantages of the system. Finally, economic viability of hybridized process for bioalcohol production is compared with the current biological process.


Assuntos
Fenômenos Biológicos , Ácidos Graxos Voláteis , Reatores Biológicos , Carboidratos , Fermentação , Esgotos , Resíduos
19.
Chemosphere ; 256: 127126, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32470736

RESUMO

Rapid industrialization and consumption of fossil fuels have led to considerable progress in the production of renewable biofuels like bioethanol. Lignocellulosic biomass such as grasses serves as cheap feedstocks for the production of bioethanol. However, the process involved in lignocellulosic bioethanol production is expensive which restricts its industrial production. The present study thus attempted to investigate a partially consolidated bioprocessing (PCB) approach using two isolated anaerobic thermophiles i.e. Bacillus paranthracis and Bacillus nitratireducens for direct conversion of ultra-sonication assisted sodium hydroxide (UA-NaOH) pretreated Denannath grass to bioethanol in co-culture consortium batch fermentation experiments. The process parameters for the PCB approach were optimized using the Box-Behnken design of Response Surface Methodology (RSM). The parameters that were considered were substrate concentration (5-10 g), incubation time (30-66 h), inoculum volume [1:1 to 3:3 (% v/v) and temperature (50-65 °C). The maximum ethanol concentration of 8.46 mM (0.39 g/L from 7.5 g/L of substrate loading) and ethanol yield (Yp/s) of 0.55 g/g of reducing sugar was obtained at 57.5 °C. In the same conditions the cellulase and xylanase activities were 0.8 U/mL and 11.53 U/mL respectively, while the lactate and acetate concentrations were 0.2 mM (0.009 g/L) and 2.9 mM (0.13 g/L) correspondingly. An increase in the substrate loadings to 250 g/L in a batch fermenter (3 L) resulted in the production of 373.35 mM (17.1 g/L) of ethanol concentration and Yp/s of 0.16 g/g of reducing sugar.


Assuntos
Bacillus/metabolismo , Biocombustíveis/análise , Reatores Biológicos/microbiologia , Etanol/análise , Pennisetum/metabolismo , Anaerobiose , Biomassa , Carboidratos , Celulase/metabolismo , Fermentação , Hidrólise , Hidróxido de Sódio
20.
Bioresour Technol ; 311: 123495, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32413641

RESUMO

This study aimed to evaluate the biomass production of Spirulina sp. LEB 18 cultivated in wastewater from the desalination process. The outdoor cultivations (210 L) were performed using as culture medium 100% wastewater supplemented with 25% of Zarrouk constituents (Tcs). In parallel, it was performed a control assay using 100% Zarrouk constituents. The biomass production in Tcs assay (1.14 g L-1) was only 9% lower than the control assay (1.25 g L-1). The Tcs assay showed a higher content of carbohydrates (52.29%), lipids (12.79%) and ash (2.69%) compared to the control assay (47.91; 7.59 and 1.29%, respectively). The biomass from the control and Tcs assays had mostly monounsaturated fatty acids C15:1 and C18:2n6t. The Spirulina sp. LEB 18 could use efficiently the nutrients from the wastewater, showing high removal efficiency of NO3- (96.99%), PO4 (83.11%) and Z (96.43%). At the same time, high added value biomolecules were produced for different purposes.


Assuntos
Microalgas , Spirulina , Biomassa , Reatores Biológicos , Carboidratos , Águas Residuárias
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