Isolation and Structural Characterization of a Second Polysaccharide from Bulbs of Lanzhou Lily

A Comparison Analysis of Quality and Metabolic Compounds in Lilies with Different Drying Treatments

The present study aimed to investigate the variations in the nutritional composition, antioxidant capacity, and metabolite profile of lilies subjected to different drying treatments, including vacuum freeze drying (VFD), hot air drying (HAD), vacuum drying (VD), and infrared drying (ID). The results show that VFD provided better preservation of the original coloration and displayed the highest levels of total amino acid content, total phenolic content, total flavonoid content, and polysaccharide and alkaloid content. Our results reveal that VFD treatment can be employed to obtain high-quality lilies with desirable appearance characteristics and nutrient compositions. Metabolomics analysis identified a total of 464 metabolites from various dried lilies. Differential metabolite screening found 150 differential metabolites across all pairwise comparisons. Hierarchical clustering analysis (HCA) indicated that lilies subjected to VFD treatment exhibited a higher abundance of steroids, saponin, flavonoids, and phenolic glycoside, whereas those subjected to HAD, VD, or ID treatments showed relatively elevated levels of specific amino acids or derivatives. This study elucidates the significant impact of various drying treatments on the quality and metabolic profile of lilies, thereby providing valuable insights for enhancing the nutritional quality of processed lilies.

Integrative analysis of metabolome and transcriptome provides new insights into functional components of Lilii Bulbus

Objective

Lilium brownii var. viridulum (LB) and L. lancifolium (LL) are the main sources of medicinal lily (Lilii Bulbus, Baihe in Chinese) in China. However, the functional components of these two species responsible for the treatment efficacy are yet not clear. In order to explore the therapeutic material basis of Lilii Bulbus, we selected L. davidii var. willmottiae (LD) only used for food as the control group to analyze the differences between LD and the other two (LB and LL).

Methods

Metabolome and transcriptome were carried out to investigate the differences of active components in LD vs LB and LD vs LL. Data of metabolome and transcriptome was analysed using various analysis methods, such as principal component analysis (PCA), hierarchical cluster analysis (HCA), and so on. Differentially expressed genes (DEGs) were enriched through KEGG and GO enrichment analysis.

Results

The PCA and HCA of the metabolome indicated the metabolites were clearly separated and varied greatly in LL and LB contrasted with LD. There were 318 significantly differential metabolites (SDMs) in LD vs LB group and 298 SDMs in LD vs LL group. Compared with LD group, the significant up-regulation of steroidal saponins and steroidal alkaloids were detected both in LB and LL groups, especially in LB group. The HCA of transcriptome indicated that there was significant difference in LB vs LD group, while the difference between LL and LD varied slightly. Additionally, 47 540 DEGs in LD vs LB group and 18 958 DEGs in LD vs LL group were identified. Notably, CYP450s involving in the biosynthesis of steroidal saponins and steroidal alkaloids were detected, and comparing with LD, CYP724, CYP710A, and CYP734A1 in LB and CYP90B in LL were all up-regulated.

Conclusion

This study suggested that steroidal saponins and steroidal alkaloids maybe the representative functional components of Lilii Bulbus, which can provide new insights for Lilii Bulbus used in the research and development of classic famous formula.

Extraction, purification, structural characteristics, biological activities, and applications of polysaccharides from the genus Lilium: A review

The genus Lilium (Lilium) has been widely used in East Asia for over 2000 years due to its rich nutritional and medicinal value, serving as both food and medicinal ingredient. Polysaccharides, as one of the most important bioactive components in Lilium, offer various health benefits. Recently, polysaccharides from Lilium plants have garnered significant attention from researchers due to their diverse biological properties including immunomodulatory, anti-oxidant, anti-diabetic, anti-tumor, anti-bacterial, anti-aging and anti-radiation effects. However, the limited comprehensive understanding of polysaccharides from Lilium plants has hindered their development and utilization. This review focuses on the extraction, purification, structural characteristics, biological activities, structure-activity relationships, applications, and relevant bibliometrics of polysaccharides from Lilium plants. Additionally, it delves into the potential development and future research directions. The aim of this article is to provide a comprehensive understanding of polysaccharides from Lilium plants and to serve as a basis for further research and development as therapeutic agents and multifunctional biomaterials.

Extraction, purification, characteristics, bioactivities, prospects, and toxicity of Lilium spp. polysaccharides

The genus Lilium has been widely used worldwide as a food and medicinal ingredient in East Asia for over 2000 years due to its higher nutritional and medicinal value. Polysaccharide is the most important bioactive ingredient in Lilium spp. and has various health benefits. Recently, Lilium spp. polysaccharides (LSPs) have attracted significant attention from industries and researchers due to their various biological properties, such as antioxidant, immunomodulatory, antitumor, antibacterial, hypoglycaemic, and anti-radiation. However, the development and utilization of LSP-based functional biomaterials and medicines are limited by a lack of comprehensive understanding regarding the structure-activity relationships (SARs), industrial applications, and safety of LSPs. This review provides an inclusive overview of the extraction, purification, structural features, bioactivities, and mechanisms of LSPs. SARs, applications, toxicities, and influences of structural modifications on bioactivities are also highlighted, and the potential development and future study direction are scrutinized. This article aims to offer a complete understanding of LSPs and provide a foundation for further research and application of LSPs as therapeutic agents and multifunctional biomaterials.

Extraction, structural characterization and immunoactivity of glucomannan type polysaccahrides from Lilium brownii var. viridulum Baker

Homogeneous polysaccharide (LBP) was extracted and purified from the bulblets of Lilium brownii var. viridulum Baker with a molecular weight of 312 kDa. The monosaccharides are composed of mannose and glucose, and the corresponding molar ratios are 0.582 and 0.418, respectively. FT-IR, LC-MS, NMR, GC-MS and HPAEC were used to analyze the functional groups, glycosidic linkages and chemical structure of LBP, which was a 1-4-linked glucomannan and contained a dodecasaccharide repeating units of →4)-β-D-Manp-(1 → 4)-β-D-Manp-(1 → 4)-β-D-Manp-(1 → 4)-β-D-Glcp-(1 → 4)-β-D-Manp-(1 → 4)-β-D-Manp-(1 → 4)-β-D-Glcp-(1 → 4)-α-D-Glcp-(1 → 4)-β-D-Glcp-(1 → 4)-β-D-Glcp-(1 → 4)-β-D-Manp-(1 → 4)-β-D-Manp-(1 → . In vitro experimental results showed that LBP had noble biocompatibility, and a low dose of 5 μg/mL LBP significantly up-regulated the mRNA expression of TNF-α, iNOS, IL-6, IL-1β and Toll-like receptors family (TLRs) in RAW 264.7 cells. In conclusion, LBP played an important role in immunomodulation, and further studies on the specific immunomodulatory mechanisms of LBP on RAW 264.7 cells are still needed.

Extraction, structure, pharmacological activity, and structural modification of Lilium polysaccharides

Polysaccharides primarily composed of glucose, arabinose, rhamnose, xylose, and galactose are pharmacologically active ingredients in Lilium. The pharmacological activities shown by polysaccharides from Lilium include antioxidant, anti-tumor, immunomodulatory, hypoglycemic, bacteriostatic, and radiation protection effects. This review provides a comprehensive summary of the distribution of Lilium medicinal resources in China, current extraction and purification methods of Lilium polysaccharide (LP), the strategies used for analyzing the polysaccharide structure and monosaccharide composition in LP, and the pharmacological activities and structural modification of LP. This review provides a basis for the development and clinical application of LP along with the conservation and utilization of Lilium resources.

Fine structure and hypoglycemic effect of a galactoglucan from the bulbs of Lanzhou lily

The present research aimed to further identify the fine structure, morphology, and thermal behaviors of a galactoglucan BHP-2 derived from Lanzhou lily bulbs through partial acid hydrolysis, methylation, 2D NMR (1H1H COSY, HSQC, and HMBC), scanning electron microscopy (SEM) and thermogravimetric-differential thermal analysis (TG-DTA). Additionally, the study assessed the potential in vitro hypoglycemic effect of BHP-2 by examining its inhibitory effect on α-glucosidase and α-amylase. The results indicated that the main backbone composition of BHP-2 consisted of →4)-α-D-Glcp-(1→, →3)-β-D-Glcp-(1 → and →6)-β-D-Galp-(1→, while the side chain composition predominantly featured →4)-α-D-Glcp-(1→, →3,5)-α-L-Araf-(1 → and →3)-β-D-Galp-(1→, attached to the C-2 and/or C-3 positions of →4)-α-D-Glcp-(1→. Terminal residues consisted of α-D-Glcp-(1 → and β-L-Araf-(1→. BHP-2 exhibited excellent thermal stability, with a microscopic surface characterized by tightly packed sheets and numerous spiral depressions, which might contribute to its remarkable in vitro hypoglycemic effect. BHP-2 showed competitive inhibition of α-amylase and mixed non-competitive inhibition of α-glucosidase, with respective IC50 values of 0.31 and 0.18 mg/mL, closely resembling to those of acarbose (0.27 and 0.12 mg/mL). These findings suggested that BHP-2 had potential as an additive for glycemic intervention.

Research progress on the hypoglycemic activity and mechanisms of natural polysaccharides

The incidence of diabetes, as a metabolic disease characterized by high blood sugar levels, is increasing every year. The predominantly western medicine treatment is associated with certain side effects, which has prompted people to turn their attention to natural active substances. Natural polysaccharide is a safe and low-toxic natural substance with various biological activities. Hypoglycemic activity is one of the important biological activities of natural polysaccharides, which has great potential for development. A systematic review of the latest research progress and possible molecular mechanisms of hypoglycemic activity of natural polysaccharides is of great significance for better understanding them. In this review, we systematically reviewed the relationship between the hypoglycemic activity of polysaccharides and their structure in terms of molecular weight, monosaccharide composition, and glycosidic bonds, and summarized underlying molecular mechanisms the hypoglycemic activity of natural polysaccharides. In addition, the potential mechanisms of natural polysaccharides improving the complications of diabetes were analyzed and discussed. This paper provides some valuable insights and important guidance for further research on the hypoglycemic mechanisms of natural polysaccharides.

The Polysaccharides from the Aerial Parts of Bupleurum chinense DC Attenuate Epilepsy-Like Behavior through Oxidative Stress Signaling Pathways

Bupleurum chinense DC. is a traditional Chinese medicine with a long medicinal history and is often used as the main ingredient in prescription drugs for epilepsy. The aerial parts of B. chinense DC. have similar efficacy and composition to B. chinense DC. Therefore, we speculated that the aerial parts of B. chinense DC. could be used in the treatment of epilepsy. Polysaccharides from the aerial parts of B. chinense DC. were selected to explore their therapeutic effects on epilepsy and their potential mechanism of action. The study is aimed at clarifying the antiepileptic effects of the polysaccharides from the aerial parts of B. chinense DC. and their potential underlying mechanisms. The chemical profile of the aerial parts of B. chinense DC. polysaccharides (ABP) was characterized by FT-IR spectrum and HPLC chromatogram. To determine the therapeutic effects of ABPs on epilepsy, we established a kainic acid- (KA-) induced rat model of epilepsy, and through H&E staining, Nissl staining, immunohistochemistry, biochemical analysis, ELISA, and Western blot analysis, we explored the mechanisms underlying the therapeutic effects of ABPs on epilepsy. The monosaccharide content of ABP included galacturonic acid (45.19%), galactose (36.63%), arabinose rhamnose (12.13%), and mannose (6.05%). Moreover, the average molecular weight of ABP was 1.38 × 10³ kDa. ABP could improve hippocampal injuries and neuronal function in the KA-induced epilepsy rat model. ABP significantly inhibited oxidative stress in the hippocampus of KA-induced rats. More importantly, ABP could regulate TREM2 activation in the PI3K/Akt/GSK-3β pathway to inhibit neuronal apoptosis, including increasing the expression of superoxide dismutase and lactate dehydrogenase and decreasing the expression of malondialdehyde. The current study defined the potential role of ABP in inhibiting the development of epilepsy, indicating that ABP could upregulate TREM2 to alleviate neuronal apoptosis, by activating the PI3K/Akt/GSK-3β pathway and oxidative stress in epilepsy.

Changes of starch and sucrose content and related gene expression during the growth and development of Lanzhou lily bulb

As the main forms of carbohydrates, starch and sucrose play a vital role in the balance and coordination of various carbohydrates. Lanzhou lily is the most popular edible lily in China, mainly distributed in the central region of Gansu. To clarify the relationship between carbohydrate metabolism and bulb development of Lanzhou lily, so as to provide a basis for the promotion of the growth and development in Lanzhou lily and its important economic value, we studied lily bulbs in the squaring stage, flowering stage, half withering stage and withering stage. The plant height, fresh weight of mother and daughter bulbs continued to increase during the whole growth period and fresh weight of stem and leaf began to decrease in the half withering stage. The content of starch, sucrose and total soluble sugar in the lily mother bulb accumulated mostly in the flowering, withering and half withering stages, respectively. Starch, sucrose and total soluble sugar accumulated in the daughter bulb with the highest concentration during the withering stage. In the transcription level, sucrose synthase (SuSy1) and sucrose invertase (INV2) expressed the highest in squaring stage, and the expression was significantly higher in the mother bulb than in the daughter bulb. In flowering stage, the expression levels of soluble starch synthase (SSS1), starch-branching enzyme (SBE) and adenosine diphosphate-glucose pyrophosphorylase (AGP1) genes were higher in the mother bulb than in the daughter bulb. Altogether, our results indicate that starch and sucrose are important for the bulb growth and development of Lanzhou lily.

The Extraction, Functionalities and Applications of Plant Polysaccharides in Fermented Foods: A Review

Plant polysaccharides, as prebiotics, fat substitutes, stabilizers, thickeners, gelling agents, thickeners and emulsifiers, have been immensely studied for improving the texture, taste and stability of fermented foods. However, their biological activities in fermented foods are not yet properly addressed in the literature. This review summarizes the classification, chemical structure, extraction and purification methods of plant polysaccharides, investigates their functionalities in fermented foods, especially the biological activities and health benefits. This review may provide references for the development of innovative fermented foods containing plant polysaccharides that are beneficial to health.

Effects of Lactobacillus plantarum Fermentation on the Chemical Structure and Antioxidant Activity of Polysaccharides from Bulbs of Lanzhou Lily

Recently, Lanzhou lily has attracted more attention because of its bioactive components specifically polysaccharides. We studied in vitro the effects of Lactobacillus plantarum fermentation on the physicochemical properties, chemical structure, and antioxidant activity of the Lanzhou lily polysaccharide. The results showed that compared with the unfermented Lanzhou lily polysaccharide (LP-W), the molecular weight (M _w) of the fermented Lanzhou lily polysaccharide (LPF-W) decreased from 4334 to 1684 kDa, the particle size decreased from 300.8 ± 6.38 to 141.9 ± 4.96 nm, and the solubility increased from 72.33 ± 3.58 to 104.27 ± 2.91 mg/mL. In addition, after fermentation, the monosaccharide composition of LPF-W changed, and the alternation of mannose residues and glucose residues disappeared. The results of the analysis of the antioxidant activity in vitro showed that compared with LP-W, the fermented LPF-W had higher DPPH radical ability, superoxide anion radical scavenging ability, and reducing efficiency, but the hydroxyl radical scavenging ability decreased. These findings provide a reference for the potential application of the lily polysaccharide as a plant-derived antioxidant in functional foods.

The extraction of phenolic acids and polysaccharides from Lilium lancifolium Thunb. using a deep eutectic solvent

Establishing a fast and effective extraction method for herbs is beneficial for the determination of their main compounds and estimating their quality. In this study, deep eutectic solvents (DESs) were optimized to simultaneously extract three main types of phenolic acids, i.e., regaloside B, regaloside C, and regaloside E, and polysaccharides from the bulbs of Lilium lancifolium Thunb. Based on the optimized extraction conditions, i.e., an extraction temperature of 50 °C, an extraction time of 40 min, a solid-liquid ratio of 1 : 25, and a ratio of water in the DES of 20%, the extracted amounts of regaloside B, regaloside C, and regaloside E reached 0.31 ± 0.06 mg g-1, 0.29 ± 0.03 mg g-1, and 3.04 ± 0.38 mg g-1, respectively. The extraction efficiencies were higher than those obtained using conventional organic solvents. Next, the polysaccharide levels were measured and compared with those obtained using a conventional hot water extraction method, and equivalent extraction efficiencies were obtained with the conventional hot water extraction method. This study provides a new application of deep eutectic solvents (DESs) for simultaneously extracting phenolic acids and polysaccharides from the bulbs of L. lancifolium Thunb. Considering the biodegradability and pharmaceutical acceptability, DESs as a class of green solvents could have wide applications in the extraction of natural products.

Metabolome-Based Discrimination Analysis of Five Lilium Bulbs Associated with Differences in Secondary Metabolites

The bulbs of several Lilium species are considered to be both functional foods and traditional medicine in northern and eastern Asia. Considering the limited information regarding the specific bioactive compounds contributing to the functional properties of these bulbs, we compared the secondary metabolites of ten Lilium bulb samples belonging to five different species, using an ultrahigh-performance liquid chromatography-electrospray ionization-tandem mass spectrometry (UPLC-ESI-MS/MS)-based secondary metabolomics approach. In total, 245 secondary metabolites were detected; further, more metabolites were detected from purple Lilium bulbs (217 compounds) than from white bulbs (123–171 compounds). Similar metabolite profiles were detected in samples within the same species irrespective of where they were collected. By combining herbal analysis and screening differential metabolites, steroid saponins were considered the key bioactive compounds in medicinal lilies. Of the 14 saponins detected, none were accumulated in the bulbs of L. davidii var. willmottiae, also called sweet lily. The purple bulbs of L. regale accumulated more secondary metabolites, and, notably, more phenolic acid compounds and flavonoids. Overall, this study elucidates the differential metabolites in lily bulbs with varying functions and colors and provides a reference for further research on functional foods and the medicinal efficacy of Lilium species.

Structural characterization of Lanzhou lily (Lilium davidii var. unicolor) polysaccharides and determination of their associated antioxidant activity

BACKGROUD

The Lanzhou lily (Lilium davidii var. unicolor) is the only Lilium species that is used for both culinary and medicinal purposes in China. Its bulbs contain various bioactive substances, such as polysaccharides, saponins and colchicine. Lanzhou lily polysaccharides are known to have anti-immunity, anti-tumor and anti-oxidation functions.

RESULTS

The present study used a Box-Behnken design to optimize the ultrasound-assisted extraction of Lanzhou lily polysaccharides. Compared to other enzymes, trypsin significantly increased the polysaccharide yields, whereas the protein content of polysaccharides extracted with trypsin was the lowest. Monosaccharide mainly includes glucose (> 50%) and mannose (> 10%). 1,1-Diphenyl-2-picrylhydrazyl radical scavenging activity, chelating activity, total antioxidant capacity and hydroxyl radical scavenging activity of Lanzhou lily polysaccharides extracted with trypsin were stronger than those extracted without enzymes (control). Structural characteristics of Lanzhou lily polysaccharides extracted with trypsin and extracted without enzymes were characterized by scanning electron microscopy and nuclear magnetic resonance spectroscopy. When water extracted polysaccharide and trypsin extracted polysaccharide concentrations were 200 μg mL^-1 , Raw264.7 proliferation rates were 101.69% and 159.41%, respectively.

CONCLUSION

The Lanzhou lily polysaccharide was identified as α-(1 → 6)-d-glucan. Consequently, the effects of both potential antioxidant and proliferative activity of trypsin are significant. © 2020 Society of Chemical Industry.