Extraction, purification, and structure characterization of polysaccharides from Crassostrea rivularis

Shellfish polysaccharides: A comprehensive review of extraction, purification, structural characterization, and beneficial health effects

Global food systems are currently facing great challenges, such as food sources, food safety, and environmental crises. Alternative nutritional resources have been proposed as part of the solution to meeting future global food demand. In the natural resources, shellfish are the major component of global aquatic animals. Although most studies focus on the allergy, toxin, and contamination of shellfish, it is also a delicious food to the human diet rich in proteins, polysaccharides, minerals, and omega-3. Among the functional ingredients, shellfish polysaccharides possess nutritional and medicinal values that arouse the great interest of researchers. The selection of the extraction approach and the experimental condition are the key factors that influence the extraction efficiency of shellfish polysaccharides. Importantly, the purification of crude polysaccharides comprises the enrichment of shellfish polysaccharides and isolation of fractions, also resulting in various structural characteristics and physicochemical properties. Chemical modification is also an efficient method to further improve the biological activities of shellfish polysaccharides. This review summarizes the extraction, purification, structural characterization, and chemical modification methods for shellfish polysaccharides. Additionally, the beneficial health effects of shellfish polysaccharides are highlighted, with an emphasis on their potential mechanism. Finally, current challenges and perspectives on shellfish polysaccharides are also spotlighted.

Size exclusion chromatography and asymmetrical flow field-flow fractionation for structural characterization of polysaccharides: A comparative review

Natural polysaccharides exhibit a wide range of biological activities, which are closely related to their structural characteristics, including their molecular weight distribution, size, monosaccharide composition, glycosidic bond types and spatial conformation, etc. Size exclusion chromatography (SEC) and asymmetrical flow field-flow fractionation (AF4), as two potent separation techniques, both harbor potential for continuous development and enhancement. This manuscript reviewed the fundamental principles and separation applications of SEC and AF4. The structural information and spatial conformation of polysaccharides can be obtained using SEC or AF4 coupled with multiple detectors. In addition, this manuscript elaborates in detail on the shear degradation of samples such as polysaccharides separated by SEC. In addition, the abnormal elution that occurs during the application of the two methods is also discussed. Both SEC and AF4 possess considerable potential for ongoing development and refinement, thereby offering increased possibilities and opportunities for polysaccharide separation and characterization.

Effect of ecotype and Enteromorpha polysaccharide supplementation on the growth performance of indigenous chickens in Northwest Ethiopia

The study was conducted to compare the growth performance of indigenous chickens and evaluate the effect of Enteromorpha prolifera (EP) supplementation on the growth of chickens. A total of 180 indigenous chicken ecotypes (Sinan, Dembecha, North Achefer, and Jawi) were used in the study. Chicken ecotype and sex had a highly significant (p < 0.001) effect on body weight and average daily gain (ADG). The highest final body weight (1811.5 ± 16.6 g) and ADG at twenty weeks of age (12.76 ± 0.12 g) were recorded for the Jawi ecotype, followed by the North Achefer. A significantly higher body weight and ADG in male chickens than female chickens were observed. The EP supplemented (EP +) chickens showed a significantly (P < 0.05) higher body weight and ADG than the non-supplemented (EP-) chickens. The interaction effect of ecotype and feed type was not statistically significant on body weight in the starter and grower phases, except at week 9. In the first four weeks, the highest (100%) and lowest (91.7%) survivability rates were recorded for the Sinan ecotype and the Jawi ecotype, respectively. In general, the Jawi and North Achefer ecotypes had better growth performance, and the Sinan ecotype relatively showed better survivability. EP supplementation could improve the growth performance of chickens.

Optimization and evaluation of Atrina pectinata polysaccharides recovered by subcritical water extraction: A promising path to natural products

In this study, the recovery of Atrina pectinata posterior adductor polysaccharides (APP-PS) using subcritical water extraction (SWE) was optimized by response surface methodology (RSM) and the physicochemical and biological properties of the recovered APP-PS were evaluated. The optimal extraction conditions, which resulted in a maximum yield of 55.58 ± 1.12 %, were temperature, 152.08 °C; extraction time, 10 min; solid-liquid ratio, 30 g/600 mL. The obtained APP-PS was found to be 88.05 ± 0.17 % total sugar. Fourier transform infrared (FT-IR) and Nuclear magnetic resonance (NMR) analyses confirmed the presence of the α-coordination of D-glucan in the polymer sample. The analysis of monosaccharide composition, along with thermogravimetric analysis, revealed the typical structure of the sample, composed of glucose alone. Total phenolic contents of APP-PS were measured as 5.47 ± 0.01 mg Gallic acid/g of dry sample and total flavonoids contents were determined to be 0.78 ± 0.06 mg Quercetin/g of dry sample. For biological activities, ABTS+, DPPH and FRAP antioxidant activities were measured to be 20.00 ± 0.71, 2.35 ± 0.05 and 4.02 ± 0.07 μg Trolox equivalent/100 g of dry sample, respectively. Additionally ACE inhibitory was confirmed to be 87.02 ± 0.47 %. These results showed that SWE is an effective method to recover biofunctional materials from marine organisms.

A review on shellfish polysaccharides: Extraction, characterization and amelioration of metabolic syndrome

Shellfish are diverse, widely distributed organisms that are a rich source of biological resources. Polysaccharides are an important components in shellfish, hence a great deal of attention has been directed at isolation and characterization of shellfish polysaccharides because of their numerous health benefits. Differences in shellfish species, habits, and environment result in the diversity of the structure and composition of polysaccharides. Thus, shellfish polysaccharides possess special biological activities. Studies have shown that shellfish polysaccharides exert biological activities, including antioxidant, antitumor, immune-regulation, hypolipidemic, antihypertensive, and antihyperglycemic effects, and are widely used in cosmetics, health products, and medicine. This review spotlights the extraction and purification methods of shellfish polysaccharides and analyses their structures, biological activities and conformational relationships; discusses the regulatory mechanism of shellfish polysaccharides on hyperlipidemia, hypertension, and hyperglycemia caused by lipid metabolism disorders; and summarizes its alleviation of lipid metabolism-related diseases. This review provides a reference for the in-depth development and utilization of shellfish polysaccharides as a functional food to regulate lipid metabolism-related diseases. To achieve high value utilization of marine shellfish resources while actively promoting the development of marine biological industry and health industry.

Immunomodulatory effects of the polysaccharide from Sinonovacula constricta on RAW264.7 macrophage cells

This study aimed to evaluate the immunomodulatory effect of the polysaccharide from Sinonovacula constricta (SCP‐1‐1) in RAW264.7 cells. SCP‐1‐1 with a molecular weight of 440.0 kDa consisted of glucose and mannose. The immunomodulatory assay results showed that SCP‐1‐1 could significantly enhance phagocytic ability, NO production, and some cytokines (TNF‐α, IL‐6, and IL‐1β) secretion of RAW264.7 cell in a dose‐dependent manner. Western blot analysis results demonstrated that SCP‐1‐1 could regulate the expression levels of the key proteins in the signaling pathways of RAW264.7 cell and might associated with NF‐κβ and PI3K signaling pathway. These findings could contribute to elucidate the immunomodulatory activities of the polysaccharide from Sinonovacula constricta.

Extraction method development for nanoplastics from oyster and fish tissues

Nanoplastics are now found in some environmental media and consumer products. However, very limited data on nanoplastics are available for one of the main human consumption sources of microplastics: seafood. Unlike microplastics, a method for extracting nanoplastics from seafood is still lacking. Herein, a combination of common extraction techniques including enzymatic digestion, sequential membrane filtration, centrifugal concentration, and purification (dialysis and sodium dodecylsulfate (SDS) incubation), was developed to extract nanoplastics from oyster and fish tissues. Corolase with subsequent lipase treatment achieved the highest digestion efficiencies (88- 89%) for non-homogenized tissues compared to other proteases and additional cellulase or H₂O₂ treatment. With the exception of polyethylene terephthalate (PET), enzymatic digestion did not change the morphology or structure of polyvinyl chloride (PVC), polyethylene (PE), or polystyrene (PS) nanoplastic particles, and the subsequent extraction procedures had good recoveries of 71- 110% for fluorescence-labeled 76-nm PVC and 100- and 750-nm PS, as validated by a Nanoparticle Tracking Analysis (NTA). Few of the 10¹¹ digested residual particles of 150- 300 nm in diameter per oyster or per serving of fish tissue were left in the method blank. Consequently, this efficient approach could be used as a pretreatment protocol for current potential nanoplastic detection methods.

Photoprotective effect of the fucose-containing polysaccharide FucoPol

This study reports the performance of FucoPol, a fucose-containing bacterial polysaccharide, as a photostable agent with high absorption yield at concentrations as low as 0.02 % (w/v). FucoPol is non-cytotoxic, efficiently protects from UVA and UVB at concentrations of 0.02-2 % (w/v) and 0.2-2 % (w/v), respectively, has over 94 % overall photostability up to 1.5 h of irradiation time. The lowest concentration studied (0.02 %, w/v) shows a sun protection factor (SPF) of 2.61 ± 0.08. The SPF-to-concentration unit ratio showed that FucoPol is about 60-fold more photoprotective than combinations of common organic and inorganic UV filters. In vitro radiation exposure experiments of adhered Vero epithelial and PM1 keratinocytic cells in the presence of 0.25 % (w/v) FucoPol further showed that cell viability was preserved, and delayed radiation-induced cell death was prevented. Overall, FucoPol outperforms common cosmetic biopolymers like xanthan and fucogel. These results are very promising for the development of bio-based sunscreen formulations.

Utilization of Response Surface Methodology in Optimization of Polysaccharides Extraction from Vietnamese Red Ganoderma lucidum by Ultrasound-Assisted Enzymatic Method and Examination of Bioactivities of the Extract

Red Ganoderma lucidum (G. lucidum) is a popular medicinal herb commonly used in Vietnamese traditional remedies due to its potential value for health. In this study, polysaccharides were extracted from G. lucidum using ultrasound-assisted enzymatic extraction method. The response surface methodology and Box-Behnken design were employed to investigate the effects of pH, extraction temperature, extraction time, and ultrasonic power on the content of polysaccharides. Based on ultraviolet-visible spectroscopy analysis, the highest content of polysaccharides in the extract was 32.08 mg/g under optimum experimental parameters including enzyme concentration of 3%, pH of 5.5, extraction temperature of 45°C, extraction time of 30 min, and ultrasonic power of 480 W. The Fourier-transform infrared spectroscopy was also used to identify the functional groups in the extracts. The molecular weights of polysaccharides were determined by gel permeation chromatography. The obtained extract was then evaluated for anticancer activities by using (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) assay, showing the anticancer activities with the half-maximal inhibitory concentration value of more than 512 μg/mL. This result suggested that UAEE could be considered as an appropriate and effective extraction method for bioactive crude polysaccharides from G. lucidum.

Extracting Conditions Optimization and Bioactivity of Polysaccharides from the Pods of Haricot Vert

Polysaccharides from the pods of haricot vert (Phaseolus vulgaris L.) were extracted using a simple heating method, by varying extracting temperature, heating time, solid-to-liquid ratio, and solvent compositions. The obtained results were processed using statistical analysis that helped to identify the optimal conditions for the polysaccharides’ extraction process. This study represents a promising production method of bioactive polysaccharides extract in the food and pharmaceutical industry.