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1.
Int J Biol Macromol ; 264(Pt 1): 130462, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38423435

RESUMO

Banana starch has attracted significant attention due to its abundant content of resistant starch. This study aims to compare the multiscale structure and functional properties of banana starch obtained from five cultivated varieties and investigate the impact of dielectric barrier discharge cold plasma (DBD) treatment on these starch characteristics. All five types of natural banana starch exhibited an elliptical and irregular shape, conforming to the CB crystal structure, with a bimodal distribution of branch chain lengths. The resistant starch content ranged from 88.9 % to 94.1 %. Variations in the amylose content, amylopectin branch chain length distribution, and structural characteristics resulted in differences in properties such as gelatinization behavior and sensitivity to DBD treatment. The DBD treatment inflicted surface damage on starch granules, reduced the amylose content, shortened the amylopectin branch chain length, and changed the relative crystallinity to varying degrees. The DBD treatment significantly increased starch solubility and light transmittance. Simultaneously, it resulted in a noteworthy decrease in peak viscosity and gelatinization enthalpy of starch paste. The in vitro digestibility test showed that 76.2 %-86.5 % of resistant starch was retained after DBD treatment. The DBD treatment renders banana starch with reduced viscosity, increased paste transparency, enhanced solubility, and broadens its potential application.


Assuntos
Musa , Gases em Plasma , Amido/química , Amilopectina/química , Amilose/química , Musa/química , Gases em Plasma/química , Amido Resistente , Viscosidade
2.
Int J Biol Macromol ; 263(Pt 2): 130011, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38340913

RESUMO

Nε-(carboxyethyl)lysine (CML), a typical advanced glycosylation end product produced during the processing of meat under high temperature, poses health risks. Active substances like polyphenols are known to inhibit the formation of harmful products during the processing of food. In this study, our objective was to prepare a double network hydrogel (DN) loaded with gallic acid using amyloid fibers and chitosan as a rigid and flexible network, respectively. The network as well as the interactions between the two networks were observed and analyzed. Chitosan concentration was the key factor regulating the structure and properties of the DN. At a chitosan concentration of 0.7%wt, the structure of DN became dense and its mechanical properties were improved, with the loading capacity and loading efficiency being increased by 143.79 % and 128.21 %, compared with those of amyloid fibril alone. Furthermore, the digestibility of gallic acid in simulated intestinal fluid was increased by 215.10 %. Moreover, adding DN to the beef patties effectively inhibited the formation of CML in a dose-response dependent manner. Addition of 3 wt% DN resulted in the inhibitory rate of CML in roast beef patties reaching a high 73.09 %. The quality and palatability of beef patties were improved. These findings suggest that DN shows great potential as an application that may be utilized to deliver active substances aimed at inhibiting CML in the meat processing industry.


Assuntos
Quitosana , Animais , Bovinos , Quitosana/farmacologia , Lisina , Amiloide , Muramidase , Hidrogéis/farmacologia , Produtos Finais de Glicação Avançada , Carne , Ácido Gálico
3.
Food Chem X ; 21: 101212, 2024 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-38389576

RESUMO

The physicochemical properties, fatty acid composition and volatile aroma compounds of cold-pressed passion fruit seed oils were analyzed. The oils were rich in linoleic acid, oleic acid and volatile compounds. A total of 108 volatile compounds including 17 aldehydes, 23 alcohols, 21 esters, 19 ketones, 6 acids, 9 alkenes, 5 pyrazines and 8 others were identified using HS-GC-IMS. The significant differences of volatile compounds in the purple and yellow passion fruit seed oils were observed via the GalleryPlot graph and distinguished by principal component analysis. The results showed that acids, alcohols, esters and ketones were major aromatic compounds in purple passion fruit seed oils, which contribute to flavors such as flowery, fruity, creamy, yogurt. Whereas the contents of aldehydes, pyrazines, alkenes were higher in yellow passion fruit seed oils, which contributes to fatty and nutty odors. The findings filled in our understanding of volatilization characteristics in passion fruit seed oils.

4.
Food Chem ; 442: 138465, 2024 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-38266414

RESUMO

Bioactive peptide's development is facing two challenges in terms of its lower yield and limited understanding of structurally orientated functionality. Therefore, peptides were prepared from wheat bran via a cocktail enzyme for achieving a higher level of hydrophobic amino acids than traditional method. The obtained peptides exhibited great antioxidant activities against H2O2-induced oxidative stress in HepG2 cells. Among them, 91 bioactive peptides were selected through the virtual screening, and their N-terminal and C-terminal contained many hydrophobic amino acids. Then the peptides with capacity to interact with Keap1 were identified by in silico simulation, because Keap1 acts as a sensor of redox insults. The results revealed that peptides DLDW and DLGL demonstrated the highest binding affinities, and a bridge was formed between Asp of DLGL and Arg415 of Klech domain, contributing to interfering Keap1-Nrf2 interaction. These findings implied a potential application of wheat bran peptides as nutraceuticals and health-promoting ingredients.


Assuntos
Antioxidantes , Peróxido de Hidrogênio , Antioxidantes/farmacologia , Antioxidantes/metabolismo , Proteína 1 Associada a ECH Semelhante a Kelch/metabolismo , Peróxido de Hidrogênio/metabolismo , Fibras na Dieta , Fator 2 Relacionado a NF-E2/genética , Fator 2 Relacionado a NF-E2/metabolismo , Peptídeos/química , Aminoácidos
5.
Food Chem ; 429: 136583, 2023 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-37517221

RESUMO

Inhibiting the formation of advanced glycation end products (AGEs) in the heat-processed food can reduce health risks related to diabetic complications. However, additives used for this purpose may also affect the sensory characteristics of food products. In this study, the effects of six hydrocolloids on the formation of AGEs were evaluated in the lysine-glucose model, with κ-carrageenan exhibited the highest inhibitory activity. Mechanistic investigations indicated that κ-carrageenan conjugated with the key intermediates of AGEs, namely glyoxal (GO) and methylglyoxal (MGO). Subsequently, the inhibitory effect of κ-carrageenan on AGEs formation in cakes was verified. The data showed that κ-carrageenan in cakes significantly inhibited the formation of fluorescent and non-fluorescent AGEs. In addition, analysis of cake characteristics and sensory evaluation showed that cakes with 1% (w/w) κ-carrageenan had the highest quality and overall acceptance. Overall, κ-carrageenan is an effective inhibitor of AGEs formation in heat-processed food.


Assuntos
Alimentos , Produtos Finais de Glicação Avançada , Carragenina , Glioxal , Aldeído Pirúvico
6.
Int J Biol Macromol ; 236: 123957, 2023 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-36907309

RESUMO

Musa spp. (banana) is consumed globally as a healthy fruit and improves the immune system. Banana blossoms are a by-product of banana harvesting rich in active substances such as polysaccharides and phenolic compounds; however, these blossoms are typically discarded as waste. In this report, a polysaccharide, MSBP11, was extracted, purified and identified from banana blossoms. MSBP11 is a neutral homogeneous polysaccharide with a molecular mass of ∼214.43 kDa and composed of arabinose and galactose at a ratio of 0.303:0.697. MSBP11 exhibited potent antioxidant and anti-glycation activities in a dose-dependent manner and can be used as a potential natural antioxidant and inhibitor of advanced glycosylation end products (AGEs). In addition, banana blossoms have been shown to decrease the levels of AGEs in chocolate brownies, which might possibly be developed as functional foods for diabetic patients. This study provides a scientific basis to further research the potential application of banana blossoms in functional foods.


Assuntos
Antioxidantes , Musa , Humanos , Antioxidantes/farmacologia , Polissacarídeos/farmacologia , Produtos Finais de Glicação Avançada , Flores , Frutas
7.
Foods ; 11(24)2022 Dec 09.
Artigo em Inglês | MEDLINE | ID: mdl-36553737

RESUMO

Extraction methods directly affect pectin extraction yield and physicochemical and structural characteristics. The effects of acid extraction (AE), ultrasonic-assisted acid extraction (UA), steam explosion pretreatment combined with acid extraction (SEA) and ultrasonic-assisted SEA (USEA) on the yield, structure, and properties of passion fruit pectin were studied. The pectin yield of UA was 6.5%, equivalent to that of AE at 60 min (5.3%), but the emulsion stability of UA pectin was poor. The pectin obtained by USEA improved emulsion stability. Compared with UA, it had higher protein content (0.62%), rhamnogalacturonan I (18.44%) and lower molecular weight (0.72 × 105 Da). In addition, SEA and USEA had high pectin extraction yields (9.9% and 10.7%) and the pectin obtained from them had lower degrees of esterification (59.3% and 68.5%), but poor thermal stability. The results showed that ultrasonic-assisted steam explosion pretreatment combined with acid extraction is a high-efficiency and high-yield method. This method obtains pectin with good emulsifying stability from passion fruit peel.

8.
Animals (Basel) ; 12(22)2022 Nov 13.
Artigo em Inglês | MEDLINE | ID: mdl-36428357

RESUMO

The intestine of animals is a complex micro-ecosystem containing a large number of microbiomes, which is essential for the host's health development. The Hainan black goat with good resistance and adaptability is a unique species in Hainan, China. These unique physiological characteristics are inseparable from their intestinal microbiota. In this study, high-throughput sequencing was used to investigate bacterial communities in different segments of the intestinal tract of Hainan black goat. The results showed that the indices of Chao1 and ACE in the cecum and colon were significantly greater than those in the ileum (p = 0.007, 0.018). According to PCoA, the intestinal flora composition of the cecum and colon is almost equivalent. In contexts of the phylum, Firmicutes, Bacteroidota, and Pseudomonadota were the dominant phyla in the gut of the Hainan black goat. While in context of the genus, the dominant groups in the gut of black goats mainly include Ruminococcaceae_UCG-005, Bacteroides, Paeniclostridium, Christensenellaceae_R-7_group, Rikenellaceae_RC9_gut_group, and Eubacterium coprostanoligenes _group, Prevotella_1, they have different proportions in different intestinal segments. The gut microbiota of Hainan black goat is mainly Firmicutes, Bacteroidota, and Pseudomonadota. Influenced by the intestinal location where they colonize, the large intestine has a more complex intestinal flora than the small intestine. In contrast, there are only minor differences between the caecum and the colon in the large intestine.

9.
Foods ; 11(22)2022 Nov 21.
Artigo em Inglês | MEDLINE | ID: mdl-36429331

RESUMO

Ultrasonic treatment combined with resveratrol modification was used to improve banana starch's solubility, thermal stability, and digestion resistance. The solubility and freeze-thaw stability of the modified starch complex significantly increased. The oil-absorption capacity increased by 20.52%, and the gelatinization temperatures increased from 64.10-73.92 °C to 70.77-75.83 °C. The storage modulus (G') and loss modulus (G″) increased after ultrasound and resveratrol treatment, and the proportion of viscosity was increased after composition with resveratrol. Additionally, the in vitro digestibility decreased from 44.12% to 40.25%. The modified complexes had release-control ability for resveratrol. X-ray diffraction (XRD) and Fourier transform infrared (FT-IR) spectroscopy demonstrated that complex structures became more compact and organized, whereas crystalline patterns were unchanged. Scanning electron microscopy (SEM) showed that the resveratrol modification caused physical change on the granular surface by creating pores and fissures. The findings can help develop antioxidant functional foods using banana starch.

10.
Foods ; 11(19)2022 Oct 08.
Artigo em Inglês | MEDLINE | ID: mdl-36230209

RESUMO

Fermentation technology is of great significance for food preservation; through fermentation, while extending the shelf life of food, it can also improve the sensory quality of food and increase its nutritional value. Compared with natural fermentation, the use of specific microorganisms for fermentation can be used to determine the direction of fermentation. Therefore, in order to better explore the effect of bacterial community structure on the quality of sugarcane juice naturally fermented and inoculated with different lactic acid bacteria in the fermentation process, the most suitable method for sugarcane juice fermentation was found, which provided a theoretical basis for the safe production of fermented sugarcane juice. In this experiment, the sugarcane juice was treated differently and divided into four groups: natural fermentation, fermentation with Lactobacillus HNK10, fermentation with Lactococcus HNK21, and HNK10 + HNK21 compound fermentation. The changes in bacterial community structure of different treatments of sugarcane juice during fermentation were analyzed by high-throughput sequencing technology, and the quality change of different treatments of sugarcane juice during fermentation was analyzed by high-performance liquid chromatography, and the change in its bacteriostatic ability was explored. The results showed that after the sugarcane juice treated with Lactobacillus HNK10 was fermented at 37 °C for 48 h, the final fermented sugarcane juice had a large abundance of lactic acid bacteria and high-quality and strong antibacterial activity. Conclusions: changes in the bacterial community structure during the fermentation of sugarcane juice affect the formation of organic acids and the change of bacteriostatic ability and directly determine the quality and shelf life of fermented sugarcane juice.

11.
Food Chem X ; 15: 100369, 2022 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-35769329

RESUMO

Phenolics have been used to suppress the formation of advanced glycation end products (AGEs) in food; however, enhancing their thermostability and photostability in foods remains a key issue. Ferulic acid (FA), quercetin (QT), and vanillic acid (VA), which reduce production of AGEs, were embedded in bovine ß-lactoglobulin (ß-LG) and their interaction mechanism was investigated. Fluorescence experiments demonstrated that FA and QT displayed typical static quenching, while VA caused fluorescence sensitization of ß-LG. Furthermore, phenolics changed the secondary structure of ß-LG by inducing the transformation from α-helices to ß-structures, with Van der Waals forces and hydrogen bonds as the primary underlying forces. The thermal and photostability of FA/QT/VA was significantly improved upon binding to ß-LG. Furthermore, QT, FA and VA demonstrated good AGEs inhibitory abilities in BSA-fructose, BSA-MGO, arginine-MGO models. These results reveal that ß-LG embedding effectively improves the thermostability and photostability of dietary phenolics in food.

12.
Front Plant Sci ; 12: 625878, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33679839

RESUMO

The excessive use and disposal of plastic packaging materials have drawn increasing concerns from the society because of the detrimental effect on environment and ecosystems. As the most widely used fruit packing material, polyethylene (PE) film is not suitable for long-term preservation of some tropical fruits, such as mangos, due to its inferior gas permeability. Cellulose based film can be made from renewable resources and is biodegradable and environmental-friendly, which makes it a promising alternative to PE as a packaging material. In this study, cellulose film synthesized from delignified banana stem fibers via an ionic liquid 1-Allyl-3-methylimidazolium chloride ([AMIm][Cl]) were evaluated as packing material for mangos preservation. The moisture vapor transmission rate and gas transmission rate of the synthesized cellulose film were 1,969.1 g/(m2⋅24 h) and 10,015.4 ml/(m2⋅24 h), respectively, which are significantly higher than those of commercial PE films. The high permeability is beneficial to the release of ethylene so that contribute to extend fruit ripening period. As a result, cellulose film packaging significantly decreased the disease and color indexes of mangos, while prolonged the storage and shelf life of marketable fruits. In addition, the cellulose film was decomposed in soils in 4 weeks, indicating an excellent biodegradability as compared to the PE plastic film.

13.
Front Chem ; 9: 814647, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-35127654

RESUMO

Biochar is a low-cost adsorbent for sorptive removal of antibiotics from wastewater, but the adsorption efficiency needs to be improved. In this study, coconut-shell biochar was activated with KOH to improve the adsorption efficiency and magnetically modified with FeCl3 to enable recycling. The amount of KOH and the concentration of FeCl3 were optimized to reduce the pollution and production cost. The KOH-activated and FeCl3-magnetized biochar gave good sulfonamide antibiotic (SA) removal. The maximum adsorption capacities for sulfadiazine, sulfamethazine and sulfamethoxazole were 294.12, 400.00 and 454.55 mg g-1, respectively, i.e., five to seven times higher than those achieved with raw biochar. More than 80% of the adsorption capacity was retained after three consecutive adsorption-desorption cycles. A combination of scanning electron microscopy, Brunauer-Emmett-Teller analysis, X-ray diffraction, Fourier-transform infrared and Raman spectroscopies, and magnetic hysteresis analysis showed that KOH activation increased the specific surface area, porosity, and number of oxygen-rich functional groups. Iron oxide particles, which were formed by FeCl3 magnetization, covered the biochar surface. The SAs were adsorbed on the modified biochar via hydrogen bonds between SA molecules and -OH/-COOH groups in the biochar. Investigation of the adsorption kinetics and isotherms showed that the adsorption process follows a pseudo-second-order kinetic model and a monolayer adsorption mechanism. The adsorption capacity at low pH was relatively high because of a combination of π+-π electron-donor-acceptor, charge-assisted hydrogen-bonding, electrostatic, and Lewis acid-base interactions, pore filling, van der Waals forces and hydrophobic interactions. The results of this study show that magnetically modified biochar has potential applications as an effective, recyclable adsorbent for antibiotic removal during wastewater treatment.

14.
Food Sci Nutr ; 7(6): 2006-2016, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31289648

RESUMO

Diabetes is a metabolic disorder disease associated with advanced glycation end products (AGEs) and protein glycation. The effect of polygonum cuspidatum extract (PE) on AGEs and Nε-(Carboxymethyl)-L-lysine formation, protein glycation, and diabetes was investigated. Six primary phenolics in a range of 12.36 mg/g for ellagic acid to 0.01 mg/g for piceid were determined in PE. In an intermediate-moisture-foods model, inhibition rate of PE was as high as 54.2% for AGEs and 78.9% for CML under aw 0.75. The protein glycation was also inhibited by PE. In a diabetic rat model, the levels of blood glucose, serum malondialdehyde, cholesterol, triglycerides, and low-density lipoproteins were effectively reduced by PE treatment. The antioxidation capacity (T-AOC) and superoxide dismutase (SOD) activity were also mediated by PE. Additionally, the activates of liver function-related enzymes including alkaline phosphatase (ALP), glutamate pyruvate transaminase (GPT), and glutamate oxaloacetate transaminase (GOT) in diabetic rat were improved by PE.

15.
Food Sci Nutr ; 7(3): 1004-1016, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30918643

RESUMO

This study evaluated the physicochemical properties of oils extracted from steam-exploded camellia seed (Camellia oleifera Abel.). Steam pressure, resident time, fatty acid composition, total phenolics, tocopherol, squalene, and sterol contents, and volatile compounds were determined. 1H NMR and FTIR spectra were performed for the structure of camellia seed oil. This study has found the highest yield of oil was 86.56% and was obtained when steam explosion pretreatment was at 1.6 MPa 30 s. Oil extracted by steam explosion pretreatment exhibited favorable physicochemical properties and stronger antioxidant activities compared to untreated oil. The compositions of fatty acid were similar between treated and untreated camellia seed oil. According to the 1H NMR and FTIR analyses, the functional groups of the oils were not significantly affected by the steam explosion pretreatment. Furans such as 2-pentyl-furan, 2-furanmethanol, and 3-methyl-furan were produced from stream-exploded camellia seed. Scanning electron microscopy revealed that steam explosion pretreatment efficiently promoted the release of oil by destroying the cell structure of camellia seed. Therefore, steam explosion can be an effective method for the camellia seed oil extraction.

16.
Food Chem ; 216: 153-60, 2017 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-27596404

RESUMO

Glycation can generate advanced glycation end products (AGE) and its intermediates methylglyoxal (MGO) and glyoxal in foods, which increase the risk of developing diabetes diseases. In this study, the effect of resveratrol against AGE formation, carbohydrate-hydrolyzing enzyme activity and trapping MGO capability were evaluated. Resveratrol showed a significant inhibition capability against AGE formation in bovine serum albumin (BSA)-fructose, BSA-MGO and arginine-MGO models with inhibition percentages of 57.94, 85.95 and 99.35%, respectively. Furthermore, resveratrol acted as a competitive inhibitor for α-amylase with IC50 3.62µg/ml, while it behaved in an uncompetitive manner for α-glucosidase with an IC50 of 17.54µg/l. A prevention of BSA protein glycation was observed in the BSA-fructose model with addition of resveratrol. Three types of resveratrol-MGO adducts were identified in the model consisting of MGO and resveratrol. The results demonstrated that resveratrol has potential in reducing glycation in foods and retarding carbohydrate-hydrolyzing enzyme activities.


Assuntos
Carboidratos/química , Produtos Finais de Glicação Avançada/metabolismo , Aldeído Pirúvico/química , Estilbenos/farmacologia , alfa-Amilases/química , alfa-Glucosidases/química , Animais , Antioxidantes/farmacologia , Bovinos , Produtos Finais de Glicação Avançada/efeitos dos fármacos , Glicosilação/efeitos dos fármacos , Hidrólise , Aldeído Pirúvico/metabolismo , Resveratrol , Soroalbumina Bovina/química , Soroalbumina Bovina/metabolismo , alfa-Amilases/metabolismo , alfa-Glucosidases/metabolismo
17.
Front Microbiol ; 7: 1648, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27822203

RESUMO

Lignocellulosic biomass is a renewable source with great potential for biofuels and bioproducts. However, the cost of cellulolytic enzymes limits the utilization of the low-cost bioresource. This study aimed to develop a consolidated bioprocessing without the need of supplementary cellulase for butyric acid production from lignocellulosic biomass. A stirred-tank reactor with a working volume of 21 L was constructed and operated in batch and semi-continuous fermentation modes with a cellulolytic butyrate-producing microbial community. The semi-continuous fermentation with intermittent discharging of the culture broth and replenishment with fresh medium achieved the highest butyric acid productivity of 2.69 g/(L· d). In semi-continuous operation mode, the butyric acid and total carboxylic acid concentrations of 16.2 and 28.9 g/L, respectively, were achieved. Over the 21-day fermentation period, their cumulative yields reached 1189 and 2048 g, respectively, corresponding to 41 and 74% of the maximum theoretical yields based on the amount of NaOH pretreated rice straw fed in. This study demonstrated that an undefined mixed culture-based consolidated bioprocessing for butyric acid production can completely eliminate the cost of supplementary cellulolytic enzymes.

18.
J Agric Food Chem ; 64(24): 5093-100, 2016 Jun 22.
Artigo em Inglês | MEDLINE | ID: mdl-27218138

RESUMO

An intermediate-moisture food (IMF) model consisting of whey protein isolate and glucose and an IMF model fortified with resveratrol were used to study the effect of resveratrol on physicochemical changes and glycation of protein-sugar-rich foods during storage. The water activity (aw) of the storage was controlled at 0.75 or 0.56. The browning rate or hardness of fortified IMFs was significantly lower than that of IMFs after 45-day storage. The rate of Maillard reaction in the samples stored at aw 0.56 was higher than that of samples stored at aw 0.75. The fortified IMFs had lower levels of AGEs (advanced glycation end products), CML (N(ε)-(carboxymethyl)-l-lysine), and insoluble protein during storage. The inhibition capability of resveratrol against glycation was also confirmed by using sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE), liquid chromatography mass spectrometry (LC-MS), and Fourier transform infrared spectroscopy (FTIR) analysis to monitor glycated proteins and protein aggregation in the samples. The results of this study suggested that resveratrol could be used as an inhibitor to reduce the formation of undesirable AGEs and other Maillard reaction products in foods during storage.


Assuntos
Aditivos Alimentares/análise , Glucose/química , Estilbenos/análise , Água/análise , Proteínas do Soro do Leite/química , Armazenamento de Alimentos , Produtos Finais de Glicação Avançada/química , Glicosilação , Reação de Maillard , Resveratrol
19.
Carbohydr Polym ; 141: 135-42, 2016 May 05.
Artigo em Inglês | MEDLINE | ID: mdl-26877005

RESUMO

Banana cellulose contained number of hydrophilic hydroxyl groups which were succinylated to be hydrophobic groups with high oil affinity. Succinic anhydride was used to modify banana cellulose in 1-allyl-3-methylimidazolium chloride ionic liquid in this study. The modified banana cellulose had a high oil absorption capacity. The effects of reaction time, temperature, and molar ratio of succinic anhydride to anhydroglucose on the degree of substitution of modified banana cellulose were evaluated. The optimal reaction condition was at a ratio of succinic anhydride and anhydroglucose 6:1 (m:m), reaction time 60min and temperature 90°C. The maximum degree of acylation reaction reached to 0.37. The characterization analysis of the modified banana cellulose was performed using X-ray diffractometer, Fourier transform infrared spectrometer, scanning electron microscopy and thermogravimetry. The oil absorption capacity and kinetics of the modified banana cellulose were evaluated at the modified cellulose dose (0.025-0.3g), initial oil amount (5-30g), and temperature (15-35°C) conditions. The maximum oil absorption capacity was 32.12g/g at the condition of the cellulose dose (0.05g), initial oil amount (25g) and temperature (15°C). The kinetics of oil absorption of the cellulose followed a pseudo-second-order model. The results of this study demonstrated that the modified banana cellulose could be used as an efficient bio-sorbent for oil adsorption.


Assuntos
Celulose/química , Líquidos Iônicos/química , Musa/química , Óleos/química , Adsorção , Anidridos Succínicos/química
20.
Molecules ; 19(7): 10563-73, 2014 Jul 18.
Artigo em Inglês | MEDLINE | ID: mdl-25045894

RESUMO

The use of α-glucosidase inhibitors is considered to be an effective strategy in the treatment of diabetes. Using a bioassay-guided fractionation technique, five Bacillus stearothermophilus α-glucosidase inhibitors were isolated from the flowers of Musa spp. (Baxijiao). Using NMR spectroscopy analysis they were identified as vanillic acid (1), ferulic acid (2), ß-sitosterol (3), daucosterol (4) and 9-(4'-hydroxyphenyl)-2-methoxyphenalen-1-one (5). The half maximal inhibitory concentration (IC50) values of compounds 1-5 were 2004.58, 1258.35, 283.67, 247.35 and 3.86 mg/L, respectively. Compared to a known α-glucosidase inhibitor (acarbose, IC50=999.31 mg/L), compounds 3, 4 and 5 showed a strong α-glucosidase inhibitory effect. A Lineweaver-Burk plot indicated that compound 5 is a mixed-competitive inhibitor, while compounds 3 and 4 are competitive inhibitors. The inhibition constants (Ki) of compounds 3, 4 and 5 were 20.09, 2.34 and 4.40 mg/L, respectively. Taken together, these data show that the compounds 3, 4 and 5 are potent α-glucosidase inhibitors.


Assuntos
Proteínas de Bactérias , Flores/química , Inibidores de Glicosídeo Hidrolases , Musa/química , Proteínas de Bactérias/antagonistas & inibidores , Proteínas de Bactérias/química , Geobacillus stearothermophilus , Inibidores de Glicosídeo Hidrolases/química , Inibidores de Glicosídeo Hidrolases/isolamento & purificação , alfa-Glucosidases/química
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