Structural Characterization and Biological Activity of Polysaccharides from Stems of Houttuynia cordata

Effect of ultrasonic degradation on the physicochemical property, structure characterization, and bioactivity of Houttuynia cordata polysaccharide

This study aimed to evaluate the influence of ultrasonic degradation on Houttuynia cordata polysaccharide (HCP) physicochemical properties, structure characterization, and bioactivities. The results indicated that the ultrasonic degradation could significantly decrease HCP's molecular weight (MW). Total polysaccharide, uronic acid content, solubility, and thermal stability of HCP increased gradually with the increase in ultrasonication power. Fourier transform infrared (FTIR) and Nuclear magnetic resonance spectroscopy (NMR) spectra proved that the primary structure of HCP had not been changed via ultrasonic degradation. Antioxidant and hypoglycemic activity results confirmed that ultrasonication enhanced the ability to scavenge free radicals (DPPH, ABTS, and OH) and improved α-glycosidase and α-amylase inhibition with the increase of ultrasonic power, which was increased in order HCP Collapse

Key Words

• Antioxidant activity
• Houttuynia cordata polysaccharide
• Hypoglycemic activity
• Polyphenols
• Structure characterization
• Ultrasonication

Collapse

MESH Headings

• Polysaccharides/chemistry
• Polysaccharides/pharmacology
• Houttuynia/chemistry
• alpha-Amylases/antagonists & inhibitors
• Ultrasonic Waves
• Antioxidants/chemistry
• Antioxidants/pharmacology
• Chemical Phenomena
• Molecular Weight
• Solubility
• Sonication
• Hypoglycemic Agents/chemistry
• Hypoglycemic Agents/pharmacology

Collapse

Grants Collapse

Affiliation(s)

Mohammed Mansour College of Food Science and Technology, Huazhong Agricultural University, Wuhan 430070, China; Key Laboratory of Environment Correlative Food Science (Huazhong Agricultural University), Ministry of Education, China; Hubei Key Laboratory of Fruit & Vegetable Processing & Quality Control, Huazhong Agricultural University, Wuhan, 430070, China; Desert Research Center (DRC), Matariya, Cairo, Egypt
Ramy M Khoder College of Food Science and Technology, Huazhong Agricultural University, Wuhan 430070, China
Lin Xiang College of Food Science and Technology, Huazhong Agricultural University, Wuhan 430070, China; Key Laboratory of Environment Correlative Food Science (Huazhong Agricultural University), Ministry of Education, China; Hubei Key Laboratory of Fruit & Vegetable Processing & Quality Control, Huazhong Agricultural University, Wuhan, 430070, China
Lan Lan Zhang College of Food Science and Technology, Huazhong Agricultural University, Wuhan 430070, China; Key Laboratory of Environment Correlative Food Science (Huazhong Agricultural University), Ministry of Education, China; Hubei Key Laboratory of Fruit & Vegetable Processing & Quality Control, Huazhong Agricultural University, Wuhan, 430070, China
Ahmed Taha Department of Food Science, Faculty of Agricultural, (Saba Basha), Alexandria University, Alexandria 21531, Egypt
Alsadig Yahya College of Food Science and Technology, Huazhong Agricultural University, Wuhan 430070, China; Key Laboratory of Environment Correlative Food Science (Huazhong Agricultural University), Ministry of Education, China; Hubei Key Laboratory of Fruit & Vegetable Processing & Quality Control, Huazhong Agricultural University, Wuhan, 430070, China
Ting Wu College of Food Science and Technology, Huazhong Agricultural University, Wuhan 430070, China; Key Laboratory of Environment Correlative Food Science (Huazhong Agricultural University), Ministry of Education, China; Hubei Key Laboratory of Fruit & Vegetable Processing & Quality Control, Huazhong Agricultural University, Wuhan, 430070, China
Hassan Barakat Department of Food Science and Human Nutrition, College of Agriculture and Food, Qassim University, Buraydah 51452, Saudi Arabia
Ibrahim Khalifa Food Technology Department, Faculty of Agriculture, Benha University, Moshtohor, Toukh 13736, Egypt
Xu Xiaoyun College of Food Science and Technology, Huazhong Agricultural University, Wuhan 430070, China; Key Laboratory of Environment Correlative Food Science (Huazhong Agricultural University), Ministry of Education, China; Hubei Key Laboratory of Fruit & Vegetable Processing & Quality Control, Huazhong Agricultural University, Wuhan, 430070, China.

Collapse

Purification, structural characterization, and in vitro immunomodulatory activity of a low-molecular-weight polysaccharide from cultivated Chinese cordyceps

Cultivated Chinese cordyceps, an optimal substitute for the endangered wild resource, has recently been produced on a large scale. This work sought to explore the structural features and immunomodulatory activity of a novel low-molecular-weight polysaccharide (CSP1a, 15.7 kDa) isolated from cultivated Chinese cordyceps. CSP1a was prepared with a multi-step process that encompassed hot water extraction, alcohol precipitation, and column chromatographic purification. The monosaccharide composition, infrared spectroscopy, methylation, and nuclear magnetic resonance results revealed that CSP1a was highly branched (with a branching degree of 49.21 %) and primarily constituted of galactose (30.60 %), glucose (12.87 %) and mannose (56.53 %), comprising 13 distinct types of glycosidic linkage fragments. The main chain of CSP1a consisted of different mannose residues, with several exposed β-d-Galf-(1→ residues in various side chains. The results from scanning electron microscopy and Congo red analyses revealed that CSP1a possessed a reticulated porous chain conformation, which enhanced its bioavailability and demonstrated its potential as a carrier. In vitro immunological investigations demonstrated that CSP1a significantly promoted splenic lymphocyte proliferation. Additionally, CSP1a increased RAW264.7 cell proliferation, improved phagocytic capacity, and stimulated the secretion of nitric oxide (NO), interleukin-6 (IL-6), and tumor necrosis factor-alpha (TNF-α) in a dose-dependent manner. Collectively, CSP1a, a novel low-molecular-weight polysaccharide galactoglucomannan with a high branching degree and reticulated porous chain conformation, was isolated for the first time from cultivated Chinese cordyceps and showed promise as a potential immunomodulator or drug carrier. These findings contribute to elucidating the polysaccharide material basis for the immune activity of Chinese cordyceps and promote its industrial development as a functional food product.

Unveiling polysaccharides of Houttuynia cordata Thunb.: Extraction, purification, structure, bioactivities, and structure-activity relationships

BACKGROUND

Houttuynia cordata Thunb. is a plant valued for both its culinary and medicinal properties, utilized in the prevention and treatment of various ailments. Houttuynia cordata Thunb. polysaccharides (HCP) exhibit a range of biological activities, including antioxidant, immune modulation, anti-inflammatory, antiviral, maintenance of gut homeostasis, and antibacterial effects, rendering them significant for research in ethnopharmacology.

PURPOSE

This review consolidates recent advancements in the extraction, isolation, purification, structural characteristics, and biological activities of Houttuynia cordata Thunb. polysaccharides, while exploring the structure-activity relationships of HCP and the prospects for future research, thereby providing valuable insights for its drug development.

METHODS

Relevant literature regarding the extraction, isolation, purification, structural analysis, and biological activities of Houttuynia cordata Thunb. polysaccharides was sourced from databases such as PubMed, ScienceDirect, Web of Science, and CNKI.

RESULTS

Houttuynia cordata Thunb. is a perennial herbaceous plant that thrives in shady, humid environments and exhibits a semi-prostrate growth form. As a traditional herb used for heat-clearing and detoxification, it is effective against various conditions, including cholera, dysentery, and hemorrhoids. Houttuynia cordata Thunb. polysaccharides are key active components that can be extracted through various methods, including water extraction, enzymatic extraction, ultrasonic-assisted extraction, acid extraction, and alkali extraction. Structural analyses of the extracted and purified polysaccharides were conducted, focusing on their monosaccharide composition, molecular weight, and glycosidic bond structure. Additionally, pharmacological investigations reveal that Houttuynia cordata Thunb. polysaccharides possess a variety of biological activities, including antioxidant, immune modulation, antiviral, anti-inflammatory, maintenance of gut homeostasis, and antibacterial effects.

CONCLUSIONS

Research on HCP has established a solid foundation regarding its monosaccharide composition, molecular weight, and glycosidic linkages, with substantial documentation of its biological activities, including antioxidant, immune-regulating, and antiviral properties. However, investigations into the structural modification of HCP and the correlation between its structure and biological activity remain relatively underexplored. Additionally, the extraction yield of HCP is significantly affected by the choice of extraction and purification methods, highlighting the necessity for further optimization of extraction protocols.

Extraction, purification, structural features, and pharmacological properties of polysaccharides from Houttuynia cordata: A review

Houttuynia cordata Thunb, also known as "Chinese medicine antibiotic", is a medicine food homology plant. It has functions of clearing heat, eliminating toxins, in folk medicine. The extraction purification and bioactivity of Houttuynia cordata polysaccharides (HCPs) have been of wide interest to researchers in recent years studies. Studies have confirmed that HCPs exhibit various biofunctionalities, such as anti-inflammatory, antiviral, antibacterial, antioxidant, immunomodulatory, regulation of gut microbiota, and gut-lung axis, as well as anti-radiation, and anti-cancer properties. Therefore, a comprehensive systematic review is needed to summarize the recent advances of HCPs and facilitate a better understanding of their biofunctionalities. This paper reviews the research progress of HCPs in extraction and purification methods, chemical structures, biological activities, possible mechanisms of action, and potential application prospects, which can provide some valuable insights and updated information for their further development and application of HCPs in the fields of therapeutic agents, functional foods, cosmetics, animal feeds.

Effects of Separation and Purification Methods on Antioxidation, Hypoglycemic and DNA Protection Activity of Fenugreek Polysaccharide

Six low molecular weight fenugreek polysaccharides (FP) were isolated and purified by ethanol stepwise precipitation (EFP-20, EFP-40, and EFP-60) and DEAE-52 cellulose column method (DFP-0, DFP-0.15, and DFP-0.3), respectively. The effects of different separation and purification techniques on the preliminary properties and biological activities of fenugreek polysaccharides were compared. The results showed that the DEAE-52 cellulose-eluted fractions had a higher total sugar content and displayed a looser structure. The molecular weights of all six fractions were in the range of 4-19 kDa, with significant changes in the ratio of galactose to mannose. All six fractions contained α-D-galactopyranose and β-D-mannopyranose structures. Activity tests showed that all six fractions possessed antioxidant, hypoglycemic and DNA-protective activities. Among them, the DFP-0 fraction showed the highest activity. Overall, different isolation and purification methods lead to changes in the properties and bioactivities of FP, which provides a theoretical basis for the development and application of FP in functional foods and drugs.

Acetylation of the polysaccharide from Houttuynia cordata rhizome and their α-glucosidase inhibition mechanism

In this study, the polysaccharide (RHCP) extracted from Houttuynia cordata rhizome was acetylated through the acetic anhydride method. The physicochemical properties of RHCP and its acetylated derivatives (Ac-RHCP) were determined by infrared spectra, scanning electron microscopy, and Congo red test. Meanwhile, the α-glucosidase inhibition mechanism of RHCP and Ac-RHCP was analyzed by inhibition kinetics, and circular dichroism and fluorescence spectroscopy. Ac-RHCP resulted in a more porous surface structure and 1.83-fold higher solubility compared with RHCP. At a concentration of 6 mg/mL, the α-glucosidase inhibition rate of Ac-RHCP was 75.40%, while that of RHCP was 44.68%. RHCP and Ac-RHCP inhibited α-glucosidase in a mixed-type manner, reduced the endogenous fluorescence of α-glucosidase, affected the microenvironment of amino acid residues, and changed the conformation of α-glucosidase. The study indicates that Ac-RHCP exhibits a certain level of α-glucosidase inhibition, demonstrating its potential as a functional food for glycemic control.

Structural characterization and anti-oxidant activity of polysaccharide HVP-1 from Volvariella volvacea

In this study, a novel homogeneous polysaccharide (HVP-1) was purified from the Volvariella volvacea. Its structural characteristics and anti-oxidant activity in vitro were further evaluated. The results revealed that HVP-1 was composed of mannose, glucose, galactose and arabinose in a molar ratio (mol %) of 55.37: 15.74: 25.20: 3.69. Its main chain consisted of →4)-β-D-Galp-(1→, →6)-α-D-Glcp-(1→, →3)-α-D-Glcp-(1→, →4)-β-D-Manp-(1→ and →3,6)-β-D-Manp-(1→. The branched structure α-L-Araf-(1→, →2)-β-D-Glcp-(1→ and →6)-β-D-Manp-(1→ were connected to →3,6)-β-D-Manp-(1→ through the O-3 position. Scanning electron microscopy (SEM) and atomic force microscopy (AFM) showed that HVP-1 had porous sheet-like structure with a triple helix conformation. Anti-oxidant activity experiments showed that HVP-1 alleviated H2O2-induced oxidative damage by reducing the accumulation of reactive oxygen species, increasing the activity of related enzymes in cells, and activating the Nrf2/HO-1 signaling pathway. These results suggested that HVP-1 had the potential to be used as a natural anti-oxidant in functional foods and pharmaceuticals.

Impact of soybean protein isolate concentration on chitosan-cellulose nanofiber edible films: Focus on structure and properties

Chitosan and cellulose nanofiber films are frequently employed as biodegradable materials for food packaging. However, many exhibit suboptimal hydrophobicity and antioxidant properties. To address these shortcomings, we enhanced the performance by adding different concentrations of soybean protein isolate (SPI) to chitosan-cellulose nanofiber (CS-CNF) films. As SPI concentration varied, the turbidity, particle size, and ζ-potential of the film-forming solutions initially decreased and subsequently increased. This suggests that 1 % SPI augments the electrostatic attraction and compatibility. Rheological analysis confirmed a pronounced apparent viscosity at this concentration. Analyses using Fourier transform infrared spectra, Raman spectra, X-ray diffraction, and Scanning electron microscope revealed the presence of hydrogen bonds and electrostatic interactions between SPI and CS-CNF, indicative of superior compatibility. When SPI concentration was set at 1 %, notable enhancements in film attributes were observed: improvements in tensile strength and elongation at break, a reduction in water vapor permeability by 8.23 %, and an elevation in the contact angle by 18.85 %. Furthermore, at this concentration, the ABTS+ and DPPH scavenging capacities of the film surged by 61.53 % and 46.18 %, respectively. Meanwhile, the films we prepare are not toxic. This research offers valuable insights for the advancement and application of protein-polysaccharide-based films.

Uncovering nutritional metabolites and candidate genes involved in flavonoid metabolism in Houttuynia cordata through combined metabolomic and transcriptomic analyses

The perennial herb Houttuynia cordata has long been cultivated and used as medicinal and edible plant in Asia. Nowadays, increasing attention is attracted due to its numerous health benefits. Flavonoids are the main chemical constituents exerting pharmacological activities. In the present study, we investigated both metabolome and transcriptome of two H. cordata accessions (6# and 7#) with distinct flavonoids contents. In total 397 metabolites, i.e., 220 flavonoids, 92 amino acids and derivatives, 20 vitamins, and 65 saccharides were abundant in aboveground part. Cyanidin-3-O-rutinoside and quercetin-3-O-galactoside were the most abundant flavonoids, which can be categorized into seven classes, namely anthocyanidins, chalcones, flavanols, flavanones, flavanonols, flavones, and flavonols. Flavonols was the most abundant group. Contents of 112 flavonoids differed significantly between the two accessions, with catechin-(7,8-bc)-4α-(3,4-dihydroxyphenyl)-dihydro-2-(3H)-one, cinchonain Id, and cinchonain Ic being the dominant flavonoid metabolites among them. Pinocembrin-7-O-neohesperidoside, pinocembrin-7-O-rutinoside, and kaempferol-3-O-galactoside-4'-O-glucoside were uniquely abundant in accession 7. Transcriptome data revealed a total of 110 different expressed genes related to flavonoid metabolism, with more highly expressed genes observed in 7#. We annotated a total of 19 differential flavonoid metabolites and 34 differentially expressed genes that are associated with the flavonoid metabolic network. Based on the transcriptome and qPCR data a total of 8 key candidate genes involved in flavonoid metabolism were identified. The ANS gene were found to play an important role in the synthesis of cyanidin-3-O-glucoside, while the CHI, F3'H and FLS genes were mainly responsible for controlling the levels of flavanones, flavones, and flavonols, respectively. Collectively, the present study provides important insights into the molecular mechanism underlying flavonoid metabolism in H. cordata.

Introduction to the Special Issue: Preparation, Physicochemical Properties and Application of Natural Plant Polysaccharides

As natural products, plant polysaccharides have been demonstrated to induce a variety of biological activities by numerous epidemiological investigations and interventional studies, including immunomodulation and antioxidant, antibacterial, antitumor, hypolipidemic, hypoglycemic processes, etc [...].

Structural Characterization, In Vitro Digestion Property, and Biological Activity of Sweet Corn Cob Polysaccharide Iron (III) Complexes

This study aimed to enhance the utilization value of sweet corn cob, an agricultural cereal byproduct. Sweet corn cob polysaccharide-ron (III) complexes were prepared at four different temperatures (40 °C, 50 °C, 60 °C, and 70 °C). It was demonstrated that the complexes prepared at different temperatures were successfully bound to iron (III), and there was no significant difference in chemical composition; and SCCP-Fe-C demonstrated the highest iron content. The structural characterization suggested that sweet corn cob polysaccharide (SCCP) formed stable β-FeOOH iron nuclei with −OH and −OOH. All the four complexes’ thermal stability was enhanced, especially in SCCP-Fe-C. In vitro iron (III) release experiments revealed that all four complexes were rapidly released and acted as iron (III) supplements. Moreover, in vitro antioxidant, α-glucosidase, and α-amylase inhibition studies revealed that the biological activities of all four complexes were enhanced compared with those of SCCP. SCCP-Fe-B and SCCP-Fe-C exhibited the highest in vitro antioxidant, α-glucosidase, and α-amylase inhibition abilities. This study will suggest using sweet corn cobs, a natural agricultural cereal byproduct, in functional foods. Furthermore, we proposed that the complexes prepared from agricultural byproducts can be used as a potential iron supplement.

Antioxidant activity and interactions between whey protein and polysaccharides from different parts of Houttuynia cordata

Houttuynia cordata polysaccharides (PSY) are known to exhibit a variety of beneficial activities, but these are currently not specifically utilized in food. Hence, using the two edible parts of Houttuynia cordata, a herbaceous plant native to Southeast Asia, this study developed polysaccharides of a stem (HCPS)-whey protein concentrate (WPC) complex and a leaf (HCPL)-WPC complex, and studied their stability, structure and antioxidant activity. The results showed that stability differed in complexes with different proportions, exhibiting only relative stability in the two complexes in which the ratio of HCPS-WPC and HCPL-WPC was 1:4, but increased stability in the HCPL-WPC complex (ζ-potential of HCPL-WPC: | -21.87 mv| >ζ-potential of HCPS-WPC: | -21.70 mv|). Structural characterization showed that there was electrostatic interaction between HCPS and WPC and between HCPL and WPC. The HCPL-WPC was found to have better antioxidant activity. The findings of this study, thus, provide a reference for the development of Houttuynia cordata polysaccharide applications in food.