Structure Characterization, Antioxidant and Immunomodulatory Activities of Polysaccharide from Pteridium aquilinum (L.) Kuhn

Three new flavonoid glycosides isolated from Pteridium aquilinum

Three new flavonoid glycosides, (S)-4',6,8-trihydroxyflavanone-7-C-glucoside (1), (R)-4',6,8- trihydroxyflavanone-7-C-glucoside (2) and distenin-7-O-β-D-glucoside (3), along with nine known flavonoids (4-12) were isolated from the aerial of Pteridium acquilinum. Their structures were elucidated by the analysis of spectroscopy data and their comparison with the reported values. The two C-glycosyl flavanones (1 and 2), were isolated from this specie, which might be chemotaxonomic markers of this specie. In addition, three new flavonoids were preliminarily examined for their anti-inflammatory activity. Compounds 1-3 inhibited the NF-κB induction by 46.3%, 59.6% and 29.2%, respectively.

Pharmacognostic evaluation and antimicrobial activity of Pteridium aquilinum (L.) Kuhn leaves (Onocleaceae) via in vitro and in silico perspectives

BACKGROUND AND OBJECTIVE

Traditionally, Pteridium aquilinum L. has been utilized as medicine for ages, however, it is not listed in the Nigerian herbal pharmacopeia, and there is no information regarding its standardization and antimicrobial activity. Therefore, the purpose of this study was to examine the pharmacognostic parameters and antimicrobial activity of Pteridium aquilinum leaf.

METHODS

Macroscopy, chemo-microscopy, fluorescence, and microscopic analyses of the leaf were investigated using standard methods. Qualitative and quantitative phytochemical screening, thin layer chromatography (TLC), GC-MS, and FTIR were also determined using standard procedures. Antioxidants were evaluated using DPPH. The antimicrobial activities of methanol extract and fractions were evaluated using Agar well diffusion method against Candida albicans, Aspergillus niger, Staphylococcus aureus, Salmonella Typhimurium, Escherichia coli, and Pseudomonas aeruginosa. The macroscopic features of P. aquilinum leaf include a bi-pinnate leaflet and alternate pinna arrangement. The GC-MS-identified compounds in the most active (DCM fraction) were docked against Candida albicans Sterol 14-alpha demethylase (5TZ1) and Escherichia coli DNA gyrase subunit B (6YD9).

RESULTS

The macroscopic features and microscopic features such as anomocytic stomata, numerous stomata in the abaxial layer, and absence of stomata in the adaxial layer were observed. Chemomicroscopy of the powdered leaves shows that the leaf contains tannins, starch, and lignin. GC-MS detected eighteen compounds. The antimicrobial test revealed that the dichloromethane fraction of P. aquilinum leaf was most active on all the test strains (bacteria and fungi) at 25 mg/mL to 100 mg/mL concentrations. Through in silico research, the binding of 1,2-benzenedicarboxylic acid, (4-hydroxybenzoyl) hydrazine, octadecadienoyl chloride, and 11,14-Eicosadienoic acid, detected in the DCM fraction by GC-MS analysis, to the active sites of 5TZ1 and 6YD9 was stable.

CONCLUSION

This research gave scientific credence to the traditional medical practice of treating infections with P. aquilinum leaves.

Effects of simulated digestion and prebiotics properties of polysaccharides extracted from Imperatae Rhizoma based on different pilot processes

Recent studies have highlighted the prebiotic potential of natural plant polysaccharides, demonstrating their role in promoting beneficial gut microbiota and improving health. However, research on the digestive properties and prebiotic activities of Imperatae Rhizoma Polysaccharides (IRPs) remains limited. This study investigated fresh Imperatae Rhizoma as the research object. After processing, dry Imperatae Rhizoma and carbonized Imperatae Rhizoma were prepared. Three polysaccharides from the fresh, dry, and carbonized Imperatae Rhizoma were extracted with traditional hot water. And another polysaccharide was obtained by cold water extraction from fresh Imperatae Rhizoma. Total four IRPs were extracted and named: IRPs-F, IRPs-D, IRPs-C, and IRPs-J. This study evaluated the prebiotic activity of four polysaccharides derived from the roots of thatch, demonstrating their resistance to digestion, their ability to promote probiotic growth, and their enhancement of short-chain fatty acid (SCFA) production. The final results show that four IRPs exhibit strong resistance to digestion and IRPs-F ability to promote the growth of beneficial probiotics, making it a promising candidate for functional foods aimed at improving intestinal health, immune regulation, and metabolic benefits. This research is highly relevant to food microbiology and holds significant potential for application in the functional food and gut health sectors.

Degradation Polysaccharides from Benincasa hispida var. chieh-qua How: Unveiling Bioactive Properties of Degraded Compounds

This study reported an effective method for the degradation of Chieh-qua (Benincasa hispida var. Chieh-qua How) polysaccharides (BHCP) by a hydrogen peroxide-ascorbic acid oxidation (H2O2-VC) system. The degradation conditions were optimized using a Box-Behnken response surface design as concentration of H2O2-VC 19.5 mM, degradation temperature 46.4 °C and degradation time 1.0 h. The average molecular weight was decreased and total sugar content was raised of the degraded polysaccharide (DBHCP). Two refined degraded polysaccharides (DBHCP-1, DBHCP-2) were purified and prepared, and their structures were analyzed by chemical and spectral analysis. The in vitro experiments showed that degraded polysaccharides (DBHCP and DBHCP-1) have better antioxidant and anti-tyrosinase activity than natural polysaccharide BHCP. These findings support the potential application of Chieh-qua polysaccharides in the food and medical industries.

From waste to wonder: exploring the hypoglycemic and anti-oxidant properties of corn processing by-products

Introduction: The industrial processing of corn (Zeamays L.) generates by-products such as corn silk, straw peels, and straw core, which contribute to adverse environmental impacts. Our study aimed to investigate sustainable approaches for mitigating these effects by evaluating the hypoglycemic potential and mechanisms of ethyl acetate fractions derived from these corn derivatives. Methods: We employed glucose consumption assays, high glucose stress tests, UPLC-QE-Orbitrap-MS analysis, molecular docking, and simulations to assess their components and efficacy. Antioxidant capacities were evaluated using DPPH, FRAP, ABTS, and •OH scavenging assays. Results: Notably, the ethyl acetate fraction extracted from straw peels (SPE) exhibited a high concentration of flavonoids and phenolic compounds along with pronounced hypoglycemic activity and antioxidant capacity. SPE significantly enhanced glucose consumption in insulin-resistant HepG2 cells while protecting HUVECs against damage caused by high glucose levels. Molecular docking analyses confirmed the interaction between active compounds and α-glucosidase as well as α-amylase, while molecular dynamic simulations indicated stability at their binding sites. Discussion: In conclusion, the hypoglycemic and antioxidative properties observed in corn by-products such as straw peels, corn silk, and straw core can be attributed to the inhibition of α-glucosidase and α-amylase activities, coupled with their rich phenolic and flavonoid content. These findings highlight the potential of these by-products for applications in healthcare management and their sustainable utilization, demonstrating significant value in the use of agricultural residues.

The traditional utilization, biological activity and chemical composition of edible fern species

ETHNOPHARMACOLOGICAL RELEVANCE

Ferns form an important part of the human diet. Young fern fiddleheads are mostly consumed as vegetables, while the rhizomes are often extracted for starch. These edible ferns are also often employed in traditional medicine, where all parts of the plant are used, mostly to prepare extracts. These extracts are applied either externally as lotions and baths or internally as potions, decoctions and teas. Ailments traditionally treated with ferns include coughs, colds, fevers, pain, burns and wounds, asthma, rheumatism, diarrhoea, or skin diseases (eczema, rashes, itching, leprosy).

AIM OF THE REVIEW

This review aims to compile the worldwide knowledge on the traditional medicinal uses of edible fern species correlating to reported biological activities and isolated bioactive compounds.

MATERIALS AND METHODS

The articles and books published on edible fern species were searched through the online databases Web of Science, Pubmed and Google Scholar, with critical evaluation of the hits. The time period up to the end of 2022 was included.

RESULTS

First, the edible fern species were identified based on the literature data. A total of 90 fern species were identified that are eaten around the world and are also used in traditional medicine. Ailments treated are often associated with inflammation or bacterial infection. However, only the most common and well-known fern species, were investigated for their biological activity. The most studied species are Blechnum orientale L., Cibotium barometz (L.) J. Sm., Diplazium esculentum (Retz.) Sw., Marsilea minuta L., Osmunda japonica Thunb., Polypodium vulgare L., and Stenochlaena palustris (Burm.) Bedd. Most of the fern extracts have been studied for their antioxidant, anti-inflammatory and antimicrobial activities. Not surprisingly, antioxidant capacity has been the most studied, with results reported for 28 edible fern species. Ferns have been found to be very rich sources of flavonoids, polyphenols, polyunsaturated fatty acids, carotenoids, terpenoids and steroids and most of these compounds are remarkable free radical scavengers responsible for the outstanding antioxidant capacity of fern extracts. As far as clinical trials are concerned, extracts from only three edible fern species have been evaluated.

CONCLUSIONS

The extracts of edible fern species exert antioxidant anti-inflammatory and related biological activities, which is consistent with their traditional medicinal use in the treatment of wounds, burns, colds, coughs, skin diseases and intestinal diseases. However, studies to prove pharmacological activities are scarce, and require chemical-biological standardization. Furthermore, correct botanical classification needs to be included in publications to simplify data acquisition. Finally, more in-depth phytochemical studies, allowing the linking of traditional use to pharmacological relevance are needed to be done in a standardized way.

Isolation, structural characterization, and bioactivities of neutral polysaccharides from Zizania latifolia

The swollen culm (also known as Jiaobai) of Zizania latifolia is formed by the smut Ustilago esculenta invades the Z. latifolia. The new tissue formed due to the symbiotic relationship has entices the attention of researchers to study its polysaccharide structure along with biological evaluation. Five fractions of polysaccharides were obtained owing to hot water extraction, alcoholic precipitation, and chromatographic purification. Bioactivity assays showed that ZLPs have good antioxidant, hypoglycemic activities and protective activity against oxidative damage. The ZLP-1 and ZLP-2 were determined to be neutral polysaccharides with high purity, exhibiting propitious bioactivity, consequently they were subjected to indispensable structural characterization. These results showed that ZLP-1 has molecular weight (Mw) of 103 kDa and glucose (Glc) (76.68 %) as the primary monosaccharide; the ZLP-2 has Mw of 122 kDa and galactose (Gal) (41.04 %) and arabinose (Ara) (27.12 %). Structural elucidation by methylation and nuclear magnetic resonance (NMR) analysis suggested ZLP-1 is a glucan, with →3)-β-Glcp-(1→3)-β-Glcp-(1→4)-β-Glcp-(1→4)-β-Glcp-(1→3,6)-β-Galp-(1→3)-β-Glcp-(1→ as the mainchain and the terminal Araf and Glcp; the ZLP-2 is a Galactoxylan, with →3,4)-β-xylp-(1→3)-β-Galp-(1→3,6)-β-Galp-(1→3,6)-β-Galp-(1→ as the mainchain and the terminal Araf and Glcp. The structural arrangements provide a chemical basis for understanding the nutritional and pharmacological activities of polysaccharides from Zizania latifolia.

Health and Environmental Hazards of the Toxic Pteridium aquilinum (L.) Kuhn (Bracken Fern)

Bracken fern (Pteridium aquilinum (L.) Kuhn) is ubiquitous and acts as a cosmopolitan weed in pastures and similar environments. Despite its historical uses, it presents risks due to toxicity. This study, conducted in the second half of 2023, aimed to assess the environmental and health hazards of P. aquilinum, primarily focusing on its carcinogenic compound, ptaquiloside. The literature was comprehensively reviewed using diverse databases, including PubMed, Web of Science, Scopus, and Google Scholar. Information was synthesized from original research articles, meta-analyses, systematic reviews, and relevant animal studies. Animals grazing on bracken fern face annual production losses due to toxin exposure. The substantial impact on biodiversity, animal health, and human well-being arises from the presence of ptaquiloside and related compounds in milk, meat, and water, along with the increasing global prevalence of P. aquilinum and its swift colonization in acidic soil and fire-damaged areas. The objectives were to identify major bioactive compounds and explore their effects at molecular, cellular, pathological, and population levels. Various cooking techniques were considered to mitigate toxin exposure, although complete elimination remains unattainable. Therefore, the findings emphasize the need for cautious consumption. In conclusion, continued research is necessary to better understand and manage its environmental and health implications.

Structure characterization of novel heteropolysaccharides from Pteridium revolutum with antioxidant and antiglycated activities

This study aims to analysis the structures of polysaccharides isolated from Pteridium revolutum and their antioxidant and antiglycated activities. Three novel water-soluble heteropolysaccharides, named PRP0, PRP1, and PRP2, were isolated from P. revolutum. The average molecular weight was determined by high performance gel permeation chromatography analysis as 1.04 × 106, 8.39 × 105, and 7.37 × 105 Da, respectively. Their structures were characterized using physicochemical and spectroscopic methods. The antioxidant and antiglycated activities were assayed in vitro. PRP0, PRP1, and PRP2 consist of l-Ara, l-Rha, d-Man, d-Xyl, d-Fuc, d-Gal, and d-Glc in different proportions. PRP1 mainly has a backbone of (1 → 3,6)-linked d-Man and (1 → 3)-linked d-Gal on main chain. PRP2 is mainly composed of (1 → 2,4)-linked d-Man and (1 → 3)-linked d-Gal on main chain. All polysaccharides have strong scavenging power on 2,2-difenil-1-picril-hidrazil and hydroxyl radicals and significantly antiglycated activity in Bovine serum albumin-Glucose model, which showing that the polysaccharides have potential application value on the functional food.

Preparation of nano-selenium from chestnut polysaccharide and characterization of its antioxidant activity

Chestnut is widely cultivated and has high nutritional value due to its richness in polysaccharides. In order to improve the antioxidant activity of chestnut polysaccharide, chestnut polysaccharide (CP) was extracted by ultrasonic-assisted water extraction and alcohol precipitation and purified by cellulose DEAE-52 exchange and Sephadex G-100 chromatography in this study. CP isolates were characterized by I₂-KI reaction, three-strand helical structure analysis, infrared spectrum analysis, and nuclear magnetic resonance detection. The results showed that CP is a pyrylan sugar with triple helical structure and connected by α-glycosidic bonds, with sugar residues 1,4-α-D-Glcp, 1,6-α-D-Galp, 1,5-α-L-Araf, 1,4-α-L-Rhap, and 1,4-β-D-Glcp in the CP backbone. After purification, the branching structure, rod, and spherical structure were significantly increased, with reduced lamellar structure. The in vitro scavenging rates of CP at 10 mg·mL^-1 against DPPH, hydroxyl radicals, and ABTS were 88.95, 41.38, and 48.16%, respectively. The DPPH free radical scavenging rate of purified polysaccharide fraction CP-1a was slightly enhanced, and the other rates showed a small decrease. Selenized chestnut polysaccharide (CP-Se) was prepared using nano-selenium method. The selenization method was optimized and stable Se-CP was obtained. When the concentration was 5 mg·mL^-1, Se-CP had significantly higher scavenging abilities 89.81 ± 2.33, 58.50 ± 1.60, and 40.66 ± 1.91% for DPPH, hydroxyl radical, and ABTS radicals, respectively, than those of CP. The results of this study provide insight into the effects purification and selenization of chestnut polysaccharide on antioxidant activity, and also provide a theoretical basis for the development of chestnut polysaccharide for use in functional foods or health products.