Total Triterpenoid Extraction from Inonotus Obliquus Using Ionic Liquids and Separation of Potential Lactate Dehydrogenase Inhibitors via Ultrafiltration High-Speed Countercurrent Chromatography

Enhancement of hepatoprotective activity of limonin from citrus seeds against acetaminophen-induced liver injury by HSCCC purification and liposomal encapsulation

Limonin is a natural tetracyclic triterpenoid compound in citrus seeds that presents hepatoprotective effects but is often discarded as agricultural waste because of its low content and low solubility. Herein, limonin with high purity (98.11%) from citrus seeds was obtained via purification by high-speed counter-current chromatography (HSCCC) and recrystallization. Limonin-loaded liposomes (Lip-LM) prepared by thin film hydration and high pressure homogenization method to enhance its solubility and hepatoprotective effect on APAP-induced liver injury (AILI). Lip-LM appeared as lipid nanoparticles under a transmission electron microscope, and showed well dispersed nano-scale size (69.04 ± 0.42 nm), high encapsulation efficiency (93.67% ± 2.51%), sustained release, fine stability. Lip-LM also exhibited significantly better hepatoprotective activity on AILI than free limonin in vivo. In summary, Lip-LM might be used as a potential hepatoprotective agent in the form of dietary supplement and provide an effective strategy to improve the potential value of citrus seeds.

Isolation and Evaluation of Erinacine A Contents in Mycelia of Hericium erinaceus Strains

Hericium erinaceus has long been favored for its remarkable nutritional and health-promoting benefits, and erinacine A is the key component responsible for the neuroprotective properties of H. erinaceus. Establishing an efficient method for separating erinacine A from H. erinaceus and screening the erinacine A-enriched strains is crucial to maximizing its benefits. Herein, we first reported that high-speed counter current chromatography (HSCCC) is an effective method for separating high-purity erinacine A. Using a two-phase solvent system composed of n-hexane/ethyl acetate/methanol/water (4.5:5:4.5:5, v/v/v/v), erinacine A with a purity of over 95% was separated. Then, we evaluated the content and yield of erinacine A in the liquid-fermented mycelia of Hericium germplasms. Both the content and yield of erinacine A varied greatly among the surveyed strains. The significant effect of the strain on the erinacine A content and yield was revealed by an analysis of variance. The highest erinacine A content and yield were observed in the mycelia of a wild strain HeG, reaching 42.16 mg/g and 358.78 mg/L, which is superior to the current highest outcomes achieved using submerged cultivation. The isolation method established and the strains screened in this study can be beneficial for the scaling up of erinacine A extraction and nutraceutical development to industrial levels.

Rapid screening and isolation of 5-lipoxygenase inhibitors in Inonotus obliquus and mechanism of action in the treatment of asthma

Accurate screening and targeted preparative isolation of active substances in natural medicines have long been two technical challenges in natural medicine research. This study outlines a new approach to improve the efficiency of natural product preparation, focusing on rapidly and accurately screening potential active ingredients in Inonotus obliquus as well as efficiently preparing 5-lipoxidase (5-LOX) inhibitors, to provide new ideas for the treatment of asthma with Inonotus obliquus. First, we used ultrafiltration (UF) mass spectrometry to screen for three potential inhibitors of 5-LOX in Inonotus obliquus. Subsequently, the inhibitory effect of the active ingredients screened in the UF assay on 5-LOX was verified using the molecular docking technique, and the potential role of the active compounds in Inonotus obliquus for the treatment of asthma was analyzed by network pharmacology. Finally, based on the above activity screening guidelines, we used semi-preparative liquid chromatography and consecutive high-speed countercurrent chromatography to isolate three high-purity 5-LOX inhibitors such as betulin, lanosterol, and quercetin. Obviously, through the above approach, we have seamlessly combined rapid discovery, screening, and centralized preparation of the active ingredient with molecular-level interactions between the active ingredient and the protease.

Relationship of phytochemicals and antioxidant activities in Gymnema inodorum leaf extracts

Gynmena inodorum (GI) is a green leafy vegetable used in the Northern Thai cuisine which has antioxidant activities and may be applicable for preventing oxidative stress and aging-related disease. However, understanding the relationship between GI phytonutrients and their antioxidant properties has been unclear. The aims of this study were to identify the GI leaf phytochemicals and to study their antioxidant activities. A chromatogram of LC-ESI-MS/QTOF-MS showed that the GI leaves were potentially composed of phenolics, quinic acids, flavonoids, and triterpenoid saponins. This study was able to authenticate quercetin, kaempferol, and triterpenoid GIA1 in the samples. The GI materials with high contents of phenolics, flavonoids, quercetin, and kaempferol showed significant relation to antioxidation and protection in endothelial cell death suppressed by reactive nitrogen species. Meanwhile, triterpenoids had a low antioxidant impact. Ultimately, GI leaves with high phenolic compounds are a promising raw material to develop as an antioxidant functional food.

Efficient Combination of Complex Chromatography, Molecular Docking and Enzyme Kinetics for Exploration of Acetylcholinesterase Inhibitors from Poria cocos

Poria cocos (P. cocos) is a traditional Chinese medicinal product with the same origin as medicine and food. It has diuretic, anti-inflammatory and liver protection properties, and has been widely used in a Chinese medicine in the treatment of Alzheimer's disease (AD). This study was conducted to explore the activity screening, isolation of acetylcholinesterase inhibitors (AChEIs), and in vitro inhibiting effect of P. cocos. The aim was to develop a new extraction process optimization method based on the Matlab genetic algorithm combined with a traditional orthogonal experiment. Moreover, bio-affinity ultrafiltration combined with molecular docking was used to screen and evaluate the activity of the AChEIs, which were subsequently isolated and purified using high-speed counter-current chromatography (HSCCC) and semi-preparative high-performance liquid chromatography (semi-preparative HPLC). The change in acetylcholinesterase (AChE) activity was tested using an enzymatic reaction kinetics experiment to reflect the inhibitory effect of active compounds on AChE and explore its mechanism of action. Five potential AChEIs were screened via bio-affinity ultrafiltration. Molecular docking results showed that they had good binding affinity for the active site of AChE. Meanwhile, the five active compounds had reversible inhibitory effects on AChE: Polyporenic acid C and Tumulosic acid were non-competitive inhibitors; 3-Epidehydrotumulosic acid was a mixed inhibitor; and Pachymic acid and Dehydrotrametenolic acid were competitive inhibitors. This study provided a basis for the comprehensive utilization of P. cocos and drug development for the treatment of AD.

Design of experiment techniques for the optimization of chromatographic analysis conditions: A review

Design of experiment (DoE) techniques have been widely used in the field of chromatographic parameters optimization as a valuable tool. A systematic literature review of the available DoE techniques applied to the development of a chromatographic analysis method is presented in this paper. First, the most common available designs and the implementation steps of DoE are comprehensively introduced. Then the studies in recent 10 years for the application of DoE techniques in various chromatographic techniques are discussed, such as capillary electrophoresis, liquid chromatography, gas chromatography, thin-layer chromatography, and high-speed countercurrent chromatography. Current problems and future outlooks are finally given to provide a certain inspiration of research in the application of DoE techniques to the different chromatographic techniques field. This review contributes to a better understanding of the DoE techniques for the efficient optimization of chromatographic analysis conditions, especially for the analysis of complex systems, such as multicomponent drugs and natural products.

Natural products targeting human lactate dehydrogenases for cancer therapy: A mini review

Reprogramming cancer metabolism has become the hallmark of cancer progression. As the key enzyme catalyzing the conversion of pyruvate to lactate in aerobic glycolysis of cancer cells, human lactate dehydrogenase (LDH) has been a promising target in the discovery of anticancer agents. Natural products are important sources of new drugs. Up to now, some natural compounds have been reported with the activity to target LDH. To give more information on the development of LDH inhibitors and application of natural products, herein, we reviewed the natural compounds with inhibition of LDH from diverse structures and discussed the future direction of the discovery of natural LDH inhibitors for cancer therapy.

In Vitro Immunomodulatory Effects of Inonotus obliquus Extracts on Resting M0 Macrophages and LPS-Induced M1 Macrophages

Background

Inonotus obliquus (Chaga) is a parasitic fungus that is distributed mainly in northeast China. Our literature research showed chaga polysaccharides have bilateral effects on tumor necrosis factor (TNF)-α and interleukin (IL)-1β levels when they exert antitumor and antidiabetic activities. The current research tried to explore the influence of chaga extracts on inflammatory factors via macrophage polarization which has bilateral immune-regulation not only on healthy tissue homeostasis but also on pathologies.

Methods

Chaga was extracted with 100°C water and precipitated with 80% ethanol. The extracts were studied on RAW264.7 macrophage at resting condition (M0) and lipopolysaccharide (LPS)-activated subtype (classic activated macrophage, M1). The IL-1β, TNF-α, nitric oxide (NO) level, and the protein expressions of M1 and alternative activated macrophage (M2) markers including IL-1β, inducible NO synthase (iNOS), mannose receptor (CD206), and arginase (Arg)-1 were compared.

Results

The 100 g extracts contained 13.7 g polysaccharides and 1.9 g polyphenols. Compared with M0, the 50 μg/mL extracts increased NO level (P < 0.05) and decreased CD206 and Arg-1 expression significantly (P < 0.05). The extracts at 100–200 μg/mL increased NO and TNF-α level (P < 0.05), but increased iNOS and IL-1β expression significantly (P < 0.05). Compared with M1, the extracts decreased NO level at 25, 50, 100, and 200 μg/mL and decreased IL-1β and TNF-α level at 100–200 μg/mL significantly (P < 0.05). At 25–200 μg/mL, the extracts significantly increased CD206 and Arg-1 expression and decreased IL-1β and iNOS expression separately (P < 0.05).

Conclusions

Our research suggested that the bilateral effects of the chaga extracts on iNOS, IL-1β, and NO level on M0/M1 macrophages might be related with chaga polysaccharides and chaga polyphenols. Some in vivo anticancer and antidiabetic research of purified chaga polysaccharides related to macrophage differentiation should be conducted further.

Anti-Inflammatory Activity of Four Triterpenoids Isolated from Poriae Cutis

In this study, triterpenoid compounds from Poriae Cutis were separated by high-speed countercurrent chromatography (HSCCC) and identified using ultra-high performance liquid chromatography quadrupole time-of-flight tandem mass spectrometry (UHPLC-QTOF-MS/MS) and nuclear magnetic resonance (NMR). The in vitro anti-inflammatory activities of the purified triterpenoids on RAW 264.7 cells were also investigated. Triterpenoids, poricoic acid B, poricoic acid A, dehydrotrametenolic acid, and dehydroeburicoic acid were obtained; their levels of purity were 90%, 92%, 93%, and 96%, respectively. The results indicated that poricoic acid B had higher anti-inflammatory activity than those of poricoic acid A by inhibiting the generation of NO in lipopolysaccharide (LPS)-induced RAW 264.7 cells. However, dehydrotrametenolic acid and dehydroeburicoic acid had no anti-inflammatory activity. In addition, the production of cytokines (TNF-α, IL-1β, and IL-6) in cells treated with poricoic acid B decreased in a dose-dependent manner in the concentration range from 10 to 40 μg/mL. The results provide evidence for the use of Poriae Cutis as a natural anti-inflammatory agent in medicines and functional foods.