Analysis of oligosaccharides from Panax ginseng by using solid-phase permethylation method combined with ultra-high-performance liquid chromatography-Q-Orbitrap/mass spectrometry

Li, Lele,Ma, Li,Guo, Yunlong,Liu, Wenlong,Wang, Yang,Liu, Shuying The Korean Society of Ginseng 2020 Journal of Ginseng Research Vol.44 No.6

Background: The reports about valuable oligosaccharides in ginseng are quite limited. There is an urgent need to develop a practical procedure to detect and analyze ginseng oligosaccharides. Methods: The oligosaccharide extracts from ginseng were permethylated by solid-phase methylation method and then were analyzed by ultra-high-performance liquid chromatography-Q-Orbitrap/MS. The sequence, linkage, and configuration information of oligosaccharides were determined by using accurate m/z value and tandem mass information. Several standard references were used to further confirm the identification. The oligosaccharide composition in white ginseng and red ginseng was compared using a multivariate statistical analysis method. Results: The nonreducing oligosaccharide erlose among 12 oligosaccharides identified was reported for the first time in ginseng. In the comparison of the oligosaccharide extracts from white ginseng and red ginseng, a clear separation was observed in the partial least squares-discriminate analysis score plot, indicating the sugar differences in these two kinds of ginseng samples. The glycans with variable importance in the projection value large than 1.0 were considered to contribute most to the classification. The contents of oligosaccharides in red ginseng were lower than those in white ginseng, and the contents of maltose, maltotriose, maltotetraose, maltopentaose, maltohexaose, maltoheptaose, maltooctaose, maltononaose, sucrose, and erlose decreased significantly (p < 0.05) in red ginseng. Conclusion: A solid-phase methylation method combined with liquid chromatography-tandem mass spectrometry was successfully applied to analyze the oligosaccharides in ginseng extracts, which provides the possibility for holistic evaluation of ginseng oligosaccharides. The comparison of oligosaccharide composition of white ginseng and red ginseng could help understand the differences in pharmacological activities between these two kinds of ginseng samples from the perspective of glycans.

Field Test on Uplift Bearing Capacity of Rock-Socketed Belled Piles

Qinke Wang,Jianlin Ma,Zili Xiao,Wenlong Chen,Yukun Ji 대한토목학회 2020 KSCE JOURNAL OF CIVIL ENGINEERING Vol.24 No.8

The thick sandstone with an upper layer of clay (2 m to 3 m) was identified at the transmission line projects in western China. Tower foundations are affected by extreme weather such as strong wind and snow all the year round, so the research of foundation uplift is very significant. Belled piles are widely used in the area due to its high uplift bearing capacity, however, further research studies regarding the uplift bearing capacity of the belled piles in this special scenario still need to be conducted. The uplift bearing characteristics of five rock-socketed belled piles were studied by field testing method. The load-displacement curves, fitting analysis of load-displacement curves, change rate of pullout stiffness, distribution of axial force alone the pile, and pile side friction were analyzed. Observation results show that the load-displacement curves of rock-socketed belled piles are steeply changed. Moreover, we find that the hyperbolic model can provide a good fitting result for load-displacement curves, and the ultimate uplift bearing capacity is suggested to be predicted by using a reduction parameter of 0.64 − 0.85. Both uplift bearing capacity coefficient Nu and utilization ratio of pile material ηincrease with the increase of L/d under a same diameter, while the growth rate decreases. In this paper, the significant size effect is observed with increasing of pile diameter. The change rate of pullout stiffness-displacement curves are consistent with the trend of the safety factor-displacement curves, and can be fitted by power function model. Additionally, the change rate of pullout stiffness at the limit state will decrease to around 154 in this study, which can be used as the instability threshold for the rock-socketed belled piles in a similar soil foundation.

Green Synthesis of Gold Nanoparticles Using Longan Polysaccharide and their Reduction of 4-nitrophenol and Biological Applications

Xiaoyu Zhang,Liyuan Fan,Yanshuai Cui,Tianming Cui,Shengfu Chen,Guanglong Ma,Wenlong Hou,Longgang Wang 성균관대학교(자연과학캠퍼스) 성균나노과학기술원 2020 NANO Vol.15 No.02

The green synthesis of gold nanoparticles (Au NPs) for catalytic and biological applications has been drawing great attention. To compare with plant extracts, the polysaccharides may be good reducing and stabilizing agents. In this work, we describe the preparation of longan polysaccharide stabilized gold nanoparticles (Aun-LP NPs) by reduction of gold ions using a green synthetic method. The formation of gold nanoparticles (Au NPs) was confirmed by UV-Vis spectra. TEM showed that Au NPs had a small size (7.8–15.6 nm) and were highly dispersed without any aggregation. XPS confirmed that the surface elemental composition of Aun-LP NPs was C, O, and Au. DLS demonstrated that Aun-LP NPs had good stability and negative zeta potential. In addition, Aun-LP NPs had high catalytic activity for the reduction of 4-nitrophenol. More importantly, Aun-LP NPs had ignorable cytotoxicity towards HeLa cells and showed good antioxidant activity. Taken together, the results indicated that longan polysaccharide can be used as reducing agents and stabilizers for the preparation of metallic nanoparticles, and the product had wide applications.

Screening a Panel of Acid-producing Strains by Developing a High-throughput Method

Lijuan Zhu,Hui Zhang,Shiyuan Wang,Anqi Zhao,Lingbo Qu,Wenlong Xiong,Md. Asraful Alam,Wenlong Ma,Yongkun Lv,Jingliang Xu 한국생물공학회 2022 Biotechnology and Bioprocess Engineering Vol.27 No.5

Organic acids are natural cellular metabolites, which are widely used in food, pharmaceutical, and chemical industries. Among them, L-lactic acid is of special interest, because it is widely used in food and pharmaceutical industries and its monopolymer (poly (lactic acid)) is a green, renewable, biodegradable, and biocompatible alternative to the petroleum-based polymers. Currently, organic acids are predominantly produced by microbial fermentation. Their productions have been substantially improved by genetic modifications, metabolic engineering, and fermentation optimizations. However, the commonly used microbial producers still suffer from low acidic tolerance. Screening higher tolerant acid-producing microorganisms from the nature is relatively less explored. The traditional fermented foods are good resources for the screening of acid-producing and probiotic microorganisms. However, they are relatively less explored, especially those foods in developing countries. To speed up the acid-producing microorganism screening, we developed and validated a high-throughput method in this study. By using this method, we screened 1,296 colonies in 4 days and obtained a panel of acid-producing microorganisms. Among them, a Lacticaseibacillus rhamnosus showed the potential for organic acid production and probiotics applications.

Transcriptional profiling reveals the molecular bases of immune regulation in Apis mellifera in response to Ascosphaera apis infection

Bo Xu,Yingzhe WANG,Shixin ZHU,Haizhu ZHOU,Changlong GOU,Wenlong DONG,Yu Wang,Yunhang GAO,Hongxia MA 한국곤충학회 2019 Entomological Research Vol.49 No.1

Chalkbrood, which results from Ascosphaera apis infection, is one of the bee diseases that causes serious damage to the bee colony. Understanding the molecular bases underlying immune response to chalkbrood disease would facilitate the genetic breeding of bees by selecting races with superior chalkbrood resistance. In this study, transcriptome sequencing was performed to identify genes and pathways involved in the immune response to As. apis infection in A. mellifera larvae. In total, 2,890 differentially expressed genes (DEGs) (FDR < 0.001) were identified between the healthy and As. apis infected bee larvae, including 2,214 up‐regulated and 676 down‐regulated unigenes. Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway classification of the DEGs revealed association with development, energy metabolism, signal transduction, disease, and immune response. Among the immune‐related genes, p38, toll‐like receptors (TLRs), integrin, and antimicrobial peptides were up‐regulated under As. apis infection. This study provides valuable gene transcriptional information towards the investigation of molecular mechanisms related to chalkbrood immune response and host pathogenesis in A. mellifera.

Antioxidant capacity, flavor and physicochemical properties of FH06 functional beverage fermented by lactic acid bacteria: a promising method to improve antioxidant activity and flavor of plant functional beverage

Yan Xian-Tao,Zhang Ziqi,Wang Yubao,Zhang Wenmiao,Zhang Longfei,Liu Yang,Chen Dawei,Wang Wenqiong,Ma Wenlong,Qian Jian-Ya,Gu Ruixia 한국응용생명화학회 2023 Applied Biological Chemistry (Appl Biol Chem) Vol.66 No.-

The ability of natural plants to treat chronic diseases is closely related to their antioxidant function. Lactic acid bacteria (LAB) fermentation is an effective way to improve the nutritional value, biological activity and flavor of food. This study investigated the pH, titratable acidity, total polysaccharide, total flavone, total saponin, total polyphenol, and antioxidant activity of the FH06 beverage before and after probiotic fermentation. Results: After fermentation, FH06 had lower contents of total polysaccharides, total flavonoids, total saponins and total polyphenols but higher titratable acidity. The antioxidant activity was tested by total antioxidant capacity (FRAP method) and DPPH· scavenging ability. The FRAP value significantly increased after fermentation (P < 0.05), and the maximum increase was observed for Lactobacillus fermentum grx08 at 25.87%. For DPPH· scavenging ability, the value of all fermentations decreased, and L. fermentum grx08 had the smallest reduction at 2.21% (P < 0.05). The results of GC–MS and sensory analysis showed that fermentation eliminated bad flavors, such as grass, cassia and bitterness, and highlighted the fruit aroma and soft sour taste. Conclusion: The FRAP value and sensory flavor of FH06 fermentation by L. fermentum grx08 were significantly improved, indicating its great potential as a functional food with both strong antioxidant activity and good flavor.