Unprecedented Neoverrucosane and Cyathane Diterpenoids with Anti-Neuroinflammatory Activity from Cultures of the Culinary-Medicinal Mushroom Hericium erinaceus.

The culinary medicinal mushroom Hericium erinaceus holds significant global esteem and has garnered heightened interest within increasingly ageing societies due to its pronounced neuroprotective and anti-neuroinflammatory properties. Within this study, two novel diterpenes, 16-carboxy-13-epi-neoverrucosane (1) and Erinacine L (2); three known xylosyl cyathane diterpenoids, Erinacine A (3), Erinacine C (4), and Erinacine F (5); and four lanostane-type triterpenoids, and three cyclic dipeptides (10-12), in addition to orcinol (13), were isolated from the rice-based cultivation medium of H. erinaceus. Their structures were determined by NMR, HR-ESI-MS, ECD, and calculated NMR. Compound 1 marks a pioneering discovery as the first verrucosane diterpene originating from basidiomycetes, amplifying the scope of fungal natural product chemistry, and the intricate stereochemistry of Compound 5 has been comprehensively assessed for the first time. Compounds 2-5 not only showed encouraging neurotrophic activity in rat adrenal pheochromocytoma PC-12 cells, but also significantly inhibited lipopolysaccharide (LPS)-induced nitric oxide (NO) production in BV2 microglia cell cultures with IC50 values as low as 5.82 ± 0.18 µM. To elucidate the mechanistic underpinnings of these bioactivities, molecular docking simulation was used to analyze and support the interaction of 1 and 2 with inducible NO synthase (iNOS), respectively. In particular, compound 2, a cyathane-xyloside containing an unconventional hemiacetal moiety, is a compelling candidate for the prevention of neurodegenerative diseases. In summation, this investigation contributes substantively to the panorama of fungal diterpene structural diversity, concurrently furnishing additional empirical substantiation for the role of cyathane diterpenes in the amelioration of neurodegenerative afflictions.

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)-ß-D-Glcp-(1 â†’ and →6)-ß-D-Galp-(1→, while the side chain composition predominantly featured →4)-α-D-Glcp-(1→, →3,5)-α-L-Araf-(1 â†’ and →3)-ß-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 â†’ and ß-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.

Molecular properties, structure, neurotrophic and anti-inflammatory activities of cultured secondary metabolites from the cultures of the mushroom Cyathus striatus CBPFE A06.

Two previously undescribed natural cyathane diterpenoids Me-dentifragilin A (1) and Epi-neocyathin O (2), and three known cyathane diterpenoids 3-5, cyathin O, neocyathin P, and cyathin I, were isolated from the rice medium of the Cyathus striatus CBPFE A06. Their structures were established by NMR spectra, and HR-ESI-MS. Compounds 1-5 displayed encouraging neurotrophic activity in PC-12 cells at doses of 5 µM. Meanwhile, 1-5 significantly inhibited LPS-induced NO generation in BV2 cells with the IC50 values ranging from 2.44 ± 0.16 to 4.33 ± 0.32 µM. Western blot analysis showed that 2 and 4 inhibited the expression of genes involved in nitric oxide (NO) production. Molecular docking revealed that five residues of inducible NO synthase (iNOS) are key residues affecting the interaction of 2 and 4 with iNOS. This study enriches the structural diversity of cyathane diterpenes and adds to the evidence that cyathane diterpenes prevent and treat neurodegenerative diseases.

Structure characterization, antioxidant and hypoglycemic activity of an arabinogalactoglucan from Scutellaria baicalensis Georgi.

An arabinogalactoglucan SBP-1 was purified from Scutellaria baicalensis by DEAE-52 and Sephadex G-100 column chromatography. The structure of SBP-1 was characterized using HPLC, IR, GC-MS, 1-D and 2-D NMR. The antioxidant and hypoglycemic activity of SBP-1 was investigated by vitro evaluation. The results showed that SBP-1 was composed of arabinose, glucose and galactose in a molar ratio of 1.0:5.9:1.1 and its Mw were 91,156. The backbone of SBP-1 was mainly composed of repeating →1)-α-D-Glcp-(4 â†’ 1)-α-D-Glcp-(3 â†’ 1)-α-D-Galp-(4→. The braches were composed of →2)-α-L-Araf-(1→, →3)-ß-D-Glcp-(1→ and α-D-Glcp-(1→, which mainly substituted at O-6 of Glc, while terminal residue was α-L-Araf-(1→ and α-D-Glcp-(1→. Vitro bioactivity showed that SBP-1 had dose-dependent antioxidant and hypoglycemic activity. The scavenging rate on ABTS, DPPH, hydroxyl and superoxide radicals was all beyond 60% as SBP-1 concentration reached 4 mg/mL, and the inhibition rate on α-glucosidase and α-amylase was both more than 80%, which was closely to that of acarbose.

Extracts of Dracocephalum tanguticum Maxim Ameliorate Acute Alcoholic Liver Disease via Regulating Transcription Factors in Mice.

Alcoholic liver disease (ALD) caused by excessive drinking is a health and economic concern worldwide. Given the high morbidity, mortality, and the progressive nature of ALD, finding effective interventions is essential. Previous studies have confirmed that edible food plants and their bioactive compounds exert a protective effect against ALD. Dracocephalum tanguticum Maxim (DTM) is one of the important traditional Tibetan medicines in China with the effect of clearing away liver heat, used for the treatment of hepatitis. In this study, the DTM chloroform extract (DtM-C), ethyl acetate extract (DtM-E), and n-butanol extract (DtM-B) were obtained by ethanol extraction combined with fractional extraction. Acute ALD was induced in mice given intragastric ethanol. Serum and liver biochemical markers were detected by ELISA. Liver histological observation, Oil Red O, and Masson's trichrome staining were performed. Liver injury cells were induced by ethanol. The cell vitality was detected by using MTT colorimetry. The expressions of Nrf2, NF-κB, STAT3, AP-1, CREB, HIF-1α, HO-1, NQO-1, GSTA1, IKB2, and Keap1 were detected by real-time polymerase chain reaction (PCR) to elucidate the mechanism of hepatoprotective effect, and the results were verified by using Western blot. The results of serum liver function indicators (ALT, AST, and ADH), serum hepatic lipid indicators (TC, TG, HDL-C, and LDL-C), and lipid peroxidation indicators (ADH, MDA, SOD, CAT, and GSH-Px) in liver tissue and liver histological observation showed that DtM-E could improve liver function, alleviate fatty degeneration, edema, cell necrosis, and liver fibrosis caused by alcohol. DtM-E also increased the vitality of EtOH-induced liver injury cells, upregulated the mRNA expression of Nrf2, HO-1, NQO-1, and GSTA1, while downregulated the expression of Keap-1, p65, and NF-κB. Western blot results were consistent with PCR. The results suggest that DtM-E has a protective effect against ALD in vitro and in vivo, and its mechanism of action may be related to the activation of Nrf2/Keap-1 and inhibition of the P65/NF-κB signaling pathways.

Allelochemicals from the Rhizosphere Soil of Potato (Solanum tuberosum L.) and Their Interactions with the Soilborne Pathogens.

To reveal the allelopathic effects of potato, seven compounds were isolated from the rhizosphere soil: 7-methoxycoumarin (1), palmitic acid (2), caffeic acid (3), chlorogenic acid (4), quercetin dehydrate (5), quercitrin (6), and rutin (7). Bioassays showed that compounds 1, 2, 4, and 6 had inhibitory effects on the growth of L. sativa and tissue culture seedlings of potato. The existence of the allelochemicals was confirmed by HPLC, and their contents were quantified with a total concentration of 9.02 µg/g in the rhizosphere soil of replanted potato. Approaches on the interactions of the allelochemicals and pathogens of potato including A. solani, B. cinerea, F. solani, F. oxysporum, C. coccodes, and V. dahlia revealed that compound 1 had inhibitory effects but compounds 2-4 promoted the colony growth of the pathogens. These findings demonstrated that the autotoxic allelopathy and enhancement of the pathogens caused by the accumulation of the allelochemicals in the continuously cropped soil should be one of the main reasons for the replant problems of potato.

Anti-aging effects on Caenorhabditis elegans of a polysaccharide, O-acetyl glucomannan, from roots of Lilium davidii var. unicolor Cotton.

The anti-aging activities on Caenorhabditis elegans of a polysaccharide, O-acetyl glucomannan (LPR), purified from roots of Lilium davidii var. unicolor Cotton, were assessed by observing the mean lifespan, reproduction, pharyngeal pumping and stress response on nematodes. Additionally, the fluorescence intensity of lipofuscin and the level of reactive oxygen species (ROS) were detected. Also the activities of superoxide dismutase (SOD), catalase (CAT) and contents of malondialdehyde (MDA) were determined by the kit method. The results showed that LPR effectively delayed the aging of C. elegans in a dose-dependent manner. When the concentration reached 4 mg/mL, LPR extended the mean lifespan of C. elegans by up to 40%, 61% (P < 0.01) and 50% (P < 0.05) under normal, thermal and oxidative stress culture conditions, respectively. Moreover, LPR remarkably increased the reproduction duration of the nematodes at a concentration of 1 mg/L, and significantly decreased the ROS and lipofuscin level of C. elegans in three dosage groups. Further study illustrated that LPR at 4 mg/mL strongly increased the activity of SOD and CAT by 39.03% (P < 0.01) and 41.89% (P < 0.05), and decreased the lipid peroxidation of MDA level in C. elegans by 52.59% (P < 0.005) compared to a control. It was inferred that LPR provided stress resistance to heat and oxidation, and prolonged the lifespan of wild type N2 C. elegans mainly by elevating the function of nematode antioxidant defense systems and by scavenging free radicals. These findings provided evidence for the anti-aging properties of this polysaccharide from L. davidii.

Structural characterization, antioxidant and antibacterial activities of two heteropolysaccharides purified from the bulbs of Lilium davidii var. unicolor Cotton.

Two heteropolysaccharides, BHP-1 and BHP-2, were separated and purified from the edible bulbs of Lilium davidii var. unicolor Cotton by anion-exchange and gel-permeation chromatography. The primary structural characteristics of BHP-1 and BHP-2 were investigated by Congo red test, X-ray diffractometry (XRD) analysis, IR, GC and NMR. The results showed that the weight-average molecular weight (MW) and number-average molecular weight (Mn) of BHP-1 and BHP-2 were nearly 1.93 × 105 g/moL, 8.86 × 104 g/moL and 3.52 × 104 g/moL, 2.95 × 104 g/moL, respectively. Glucose and mannose comprised BHP-1 in a relative molar ratio of 5.9:2.0, and BHP-2 was consisted of glucose, galactose, mannose and arabinose with approximate molar ratios of 8.3:1.5:1.0:1.1. Their backbone mainly contained α-(1 → 4)-linked d-glucopyranosyl. In addition, the C-6 of the glucose and C-2 of mannose residue of BHP-1 and BHP-2 were substituted. The two polysaccharides were semi-crystalline substance with multi-branching structure and triple helix conformation. Bioassays showed that BHP-1 and BHP-2 had effective antioxidant activities evaluated by DPPH, scavenging superoxide radical and OH radical in a dose-dependent manner. The two heteropolysaccharides also displayed distinct and selective antibacterial activity against B. cereus, P. putida, M. luteus and K. pneumonia with inhibition zones of 13 mm, 16 mm, 17 mm, 23 mm and 12 mm, 17 mm, 19 mm, 20 mm, respectively. These findings provided a reference for potential applications of the polysaccharides from L. davidii as natural antioxidants and antibacterial agents in food and pharmaceuticals.

Purification, characterization and antioxidant activities of a polysaccharide from the roots of Lilium davidii var. unicolor Cotton.

A polysaccharide (LPR) was separated from the roots of Lilium davidii var. unicolor Cotton with hot water extraction, ethanol precipitation, and purification by anion-exchange and gel-permeation chromatography. LPR was characterized. The weight-average molecular weight (MW) of LPR was 5.12 × 104 g/moL. Glucose and mannose comprised LPR with a molar ratio of 2.9:3.3. IR, NMR and methylation analysis showed that LPR was a natural O-acetyl glucomannan, the backbone mainly contained ß-(1 → 4)-linked d-glucopyranosyl and ß-(1 → 4)-linked D-mannopyanosyl, and the branches probably linked at O-2 and/or O-3 of the mannosyl and glucosyl residues. The acetyl groups mainly attached at O-2 or O-3 of mannosyl residues. X-ray diffractometric (XRD) analysis and scanning electron microscopy (SEM) analysis revealed that LPR was a semi-crystalline substance with porous lamellar structure. Bioassays in vitro indicated that LPR had distinct scavenging activities on hydroxyl radical and DPPH radical. These findings provided a reference for functional underutilization roots of L. davidii as natural antioxidant in food and pharmaceutical industry.