scholarly journals Antifungal and Antioxidant Properties of Chitosan Polymers Obtained from Nontraditional Polybius henslowii Sources

Marine Drugs ◽  
2019 ◽  
Vol 17 (4) ◽  
pp. 239 ◽  
Author(s):  
Francisco Avelelas ◽  
André Horta ◽  
Luís F.V. Pinto ◽  
Sónia Cotrim Marques ◽  
Paulo Marques Nunes ◽  
...  

Chitin was extracted from Polybius henslowii, a swimming crab, captured in large quantities throughout the Portuguese coast by purse seine vessels as bycatch. After standard chitin extraction procedures, water-soluble chitosan products were obtained via two different methods: (1) N-acetylation with the addition of acetic anhydride and (2) a reaction with hydrogen peroxide. The chemical structure and molecular weight of chitosan derivatives, water-soluble chitosan (WSC) and chitooligosaccharides (COS), were confirmed by Fourier Transform Infrared Spectroscopy (FT-IR) and gel permeation chromatography (GPC). Antioxidant and metal chelation activities were evaluated, and the growth inhibition capacity was tested on four phytopatogens. The chitooligosaccharides from pereopods (pCOS) and shell body parts (sCOS) inhibited all fungal species tested, particularly Cryphonectria parasitica with 84.7% and 85.5%, respectively. Both radical scavenging and antifungal activities proved to be dose-dependent. Chitooligosaccharides with a low molecular weight (2.7, 7.4, and 10.4 Kg·mol−1) showed the highest activity among all properties tested. These results suggested that chitosan derivatives from P. henslowii raw material could potentially be used against phytopathogens or as ingredient in cosmetics and other products related to oxidative stress.

Fisheries ◽  
2020 ◽  
Vol 2020 (2) ◽  
pp. 113-117
Author(s):  
Olga Mezenova ◽  
Vladimir Wolkov ◽  
Larisa Baydalinova ◽  
Natalia Mezenova ◽  
Svetlana Agafonova ◽  
...  

The authors study three fractions obtained as a result of hydrolysis of smoked sprat heads (under temperature of 130oC and presser of 0.25 MPa) – fat, protein water-soluble, and protein-and-mineral ones. Waste from sprat production of two fish canning complexes of the Kaliningrad Region - “RosCon” and “Kolkhoz for the Motherland” - was used as raw material. Hydrolysis was carried out in an aqueous medium in two ways - with preliminary separation of fat and without this operation. The protein fraction was sublimated and its quantitative and qualitative indices were examined - mass yield, solubility, chemical composition and molecular fractional composition of the obtained peptide fractions were determined. The output of sublimated protein fractions is practically independent of the type of raw material and the method of pre-treatment and is 6.47.9% of the mass of raw materials. The chemical composition of protein fractions varies widely in terms of fat (1.4–8.3%), minerals (9.8–13.4%) and proteins (72.1–80.2%). The solubility of the peptide fractions ranged from 91-98%. The molecular weight assessment results showed a high content of a low molecular weight fraction of peptides with an MM of less than 10 kDa in all experimental samples (about 38%). This indicates a high digestibility and biological value of the obtained peptide compositions. Sublimated peptide compositions had typical organoleptic characteristics, pleasant aroma and taste of smoked fish. Ключевые


Molecules ◽  
2019 ◽  
Vol 24 (12) ◽  
pp. 2329 ◽  
Author(s):  
Erna Li ◽  
Shiyuan Yang ◽  
Yuxiao Zou ◽  
Weiwei Cheng ◽  
Bing Li ◽  
...  

A water-soluble oligosaccharide termed EMOS-1a was prepared by enzymatic hydrolysis of polysaccharides purified from mulberries by column chromatography. The chemical structure of the purified fraction was investigated by ultraviolet spectroscopy, Fourier-transform infrared spectroscopy, and gas chromatography–mass spectrometry, which indicated that galactose was the main constituent of EMOS-1a. Chemical analyses showed that the uronic acid and sulfate content of EMOS-1a were 5.6% and 8.35%, respectively, while gel permeation chromatography showed that EMOS-1a had an average molecular weight of 987 Da. The antioxidant activities of EMOS-1a were next investigated, and EMOS-1a exhibited concentration-dependent 1,1-diphenyl-2-picrylhydrazyl radical scavenging activity, Trolox equivalent antioxidant capacity, and ferric reducing antioxidant power. The level of proliferation of Lactobacillus rhamnosus reached 1420 ± 16% when 4% (w/v) EMOS-1a was added, where the number of colonies in MRS (de Man, Rogosa, and Sharpe) medium with no added oligosaccharide was defined as 100% proliferation. These results indicate that the oligosaccharide EMOS-1a could be used as a natural antioxidant in prebiotic preparations.


Polymers ◽  
2019 ◽  
Vol 11 (12) ◽  
pp. 2092 ◽  
Author(s):  
Miaomiao Xu ◽  
Chao Wang ◽  
Gaojin Lyu ◽  
Lei Zhong ◽  
Liyuan Yang ◽  
...  

Xylose residue (XR), after diluted acid treatment of corncob, consists of cellulose and lignin. However, structural changes of XR lignin have not been investigated comprehensively, and this has seriously hindered the efficient utilization of lignin. In this study, corncob milled wood lignin (CC MWL), and xylose residue milled wood lignin (XR MWL) were isolated according to the modified milled wood lignin (MWL) method. The structural features of two lignin fractions were thoroughly investigated via fourier transform infrared spectroscopy (FTIR), gel permeation chromatography (GPC), thermogravimetric analysis (TGA) and two dimensional nuclear magnetic resonance (2D NMR) spectroscopy techniques. XR MWL with higher yield and lower bound carbohydrate contents presented more phenolic OH contents than CC MWL due to partial cleavage of β-O-4. Furthermore, the molecular weights of XR MWL were increased, possibly because of condensation of the lignin during the xylose production. A study on antioxidant activity showed that XR lignin had better radical scavenging ability than that of 2,6-Di-tert-butyl-4-methyl-phenol (BHT) and CC MWL. The results suggested that the lignin in xylose residue, showing great antioxidant properties, has potential applications in food additives.


2014 ◽  
Vol 2014 ◽  
pp. 1-7 ◽  
Author(s):  
Ming Yuan ◽  
Xuejing Jia ◽  
Chunbang Ding ◽  
Shu Yuan ◽  
Zhongwei Zhang ◽  
...  

Hawk tea (Litsea coreanavar.lanuginose) is a very popular herbal tea in the southwest of China. According to the maturity degree of raw materials, Hawk tea can usually be divided into three types: Hawk bud tea (HB), Hawk primary leaf tea (HP), and Hawk mature leaf tea (HM). In this study, some of the bioactive constituents and antioxidant properties of the three kinds of Hawk tea infusions were comparatively investigated. The results showed that the contents of total flavonoids, vitamin C, and carbohydrates in Hawk bud tea infusion (HBI) were higher than those in Hawk primary leaf tea infusion (HPI) and Hawk mature leaf tea infusion (HMI). HPI had higher contents of total polyphenols and exhibited better DPPH radical scavenging activity and ferric reducing activity power. HBI could provide more effective protection against erythrocyte hemolysis. As age is going from bud to mature leaf, the ability to inhibit the formation of low density lipoprotein (LDL) conjugated diene and the loss of tryptophan fluorescence decreased. The bioactive constituents and antioxidant activities of Hawk tea infusions were significantly affected by the maturity degree of the raw material.


Author(s):  
G. F. Prozorova ◽  
A. I. Emel’yanov ◽  
S. A. Korzhova

New water-soluble functional copolymers based on 1-vinyl-1,2,4-triazole and allylamine were synthesized under the action of free-radical initiation conditions and azobisisobutyric acid dinitrile. Сopolymers of various compositions with a molecular weight of 1287–30204 Da were obtained by varying reaction conditions. The structure, molecular weight and physicochemical properties of the copolymers were determined using elemental analysis, IR and NMR 1H-spectroscopy, gel permeation chromatography, potentiometric and turbidimetric titration, as well as dynamic light scattering and thermogravimetric analysis. It was established that the obtained copolymers, exhibiting the properties of high-resistance organic semiconductors, are characterized by a specific electrical conductivity of 10-13 – 10-14 S/cm and high resistance to thermal destruction (up to 260–280 °C). These copolymers are promising as stabilizing polymer matrices in the formation of biologically active water-soluble hybrid organic-inorganic nanocomposites.


2021 ◽  
Vol 3 (1) ◽  
Author(s):  
Fuhao Wang ◽  
Lu Huang ◽  
Xingxing Yuan ◽  
Xiaoyan Zhang ◽  
Luping Guo ◽  
...  

Abstract This study aimed to investigate the proximate and phytochemicals present in seeds of 24 mung bean (Vigna radiate L.) genotypes from four provinces of China for estimating their nutritional and antioxidant properties. Proximate analysis of mung bean genotypes revealed that starch, protein, fat, ash and water-soluble polysaccharide ranged from 39.54–60.66, 17.36–24.89, 4.24–12.18, 2.78–3.53 and 1.99–2.96 g/100 g respectively. The five principal fatty acids detected in mung beans were stearic acid, palmitic acid, linoleic acid, oleic acid, and linolenic acid. The contents of insoluble-bound phenolic compounds, soluble phenolic compounds, and flavonoids ranged from 0.78 to 1.5 mg GAE g− 1, 1.78 to 4.10 mg GAE g− 1, and 1.25 to 3.52 mg RE g− 1, respectively. The black seed coat mung bean genotype M13 (Suheilv 1) exhibited highest flavonoid and phenolic contents which showed strong antioxidant activity. Two flavonoids (vitexin and isovitexin) and four phenolic acids (caffeic, syringic acid, p-coumaric, and ferulic acids) were identified by HPLC. Vitexin and isovitexin were the major phenolic compounds in all mung bean genotypes. The content of soluble phenolic compounds had positive correlation with DPPH (r2 = 0.713) and ABTS (r2 = 0.665) radical scavenging activities. Principal component analysis indicated that the first two principal components could reflect most details on mung bean with a cumulative contribution rate of 66.1%. Twenty-four mung bean genotypes were classified into four groups based on their phenolic compounds contents and antioxidant activities. The present study highlights the importance of these mung bean genotypes as a source of nature antioxidant ingredient for the development of functional foods or a source of health promoting food. Graphical Abstract


2018 ◽  
Vol 12 (3) ◽  
Author(s):  
O. Nikitina ◽  
N. Cherno ◽  
S. Ozolina

Nowadays, it is recognized that a lot of polysaccharides are biologically active. It is well known that these biomolecules show the highest level of their activity if they are water-soluble preparations, their molecular weight being 15–25 kDa, and if they preserve the supramolecular structure of carbohydrates. Basing on the fact that β-glucans of mushrooms are characterized by the antitumor, anticoagulant, anti-inflammatory, and immunomodulatory activities, it is important to determine whether regional raw material contains polysaccharides of a similar structure, and to define the conditions for their fragmentation to obtain products with a given molecular weight. The purpose of the work was to characterize the features of the structure of the hemicellulose complex of the Agaricus bisporous and Pleurotus ostreatus and products of their limited enzymatic hydrolysis. To determine the primary structure of hemicellulose polysaccharides, the 1H-NMR spectra of the samples were registered. It has been shown that β-D-(1→3)/β-(1→6)-glucan dominates in the hemicellulose of Pleurotus ostreatus. Among the hemicelluloses in the Agaricus bisporis, the main polysaccharide was galactoglucan. Its main chain consisted of β-D-glucopyranose residues interconnected with (1→3)-glucosidic bonds. The positions of O-6 monosaccharide are joined by the side branches in the form of β-D-glucopyranoses and the terminal residues of β-D-galactopyranoses. The hemicelluloses of Pleurotus ostreatus also contain manogalactan. Complexes of hemicelluloses of both types of mushrooms contain linear α-(1→3)-glucan in small quantities. It has been studied how the molecular-weight distribution of products of limited hydrolysis of hemicelluloses depends on the conditions of their treatment with the enzyme with β-(1→3)-glucanase activity. The maximum accumulation of a fraction with a given molecular weight of 15–25 kDa was observed at a ratio of E:S = 1:45 and treatment time of 21 hours. A specific reaction with congo red has proved there is a triple helical conformation of the main chain of the polysaccharide for this fraction of carbohydrates, so the supramolecular structure of the molecule is preserved.  


2013 ◽  
Vol 91 (2) ◽  
pp. 508-517 ◽  
Author(s):  
Warayuth Sajomsang ◽  
Pattarapond Gonil ◽  
Uracha Rungsardthong Ruktanonchai ◽  
Maleenart Petchsangsai ◽  
Praneet Opanasopit ◽  
...  

Holzforschung ◽  
2016 ◽  
Vol 70 (4) ◽  
pp. 297-304 ◽  
Author(s):  
Nanlong Hong ◽  
Wei Yu ◽  
Yuyuan Xue ◽  
Weimei Zeng ◽  
Jinhao Huang ◽  
...  

Abstract A new family of water-soluble lignosulfonate polymers with ultrahigh molecular weight (Mw) was developed based on alkali lignin (AL) as starting material in a one-pot reaction in two steps: sulfomethylation of AL as raw material led to AL-S and this material was subsequently cross-linked via alkylation with 1,6-dibromohexane (alkAL-S). Gel permeation chromatography showed a significant increase of Mw from 5200 Da of AL-S to 201 000 Da of alkAL-S with high degree of alkylation. Fourier transform infrared spectroscopy (FTIR) and proton nuclear magnetic resonance spectroscopy and functional group analysis confirmed the efficient polymerization by a nucleophilic substitution reaction mechanism. Additionally, alkAL-S with high Mw showed unexpected viscosity-reducing effect, stability and good rheological properties on a low-rank coal-water slurry (CWS), which are even better than those obtained by naphthalene sulfonate formaldehyde (NSF) as additive. The adsorption properties of the new products were also characterized via a quartz crystal microbalance combined with dissipation monitoring (QCM-D method). Cross-linked structure, large steric hindrance from high Mw and suitable amphiphilic properties of alkAL-S polymers contribute together to the highly improved dispersion performances for CWS.


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