Oligomeric phloroglucinols with hAChE inhibitory and antibacterial activities from tropic Rhodomyrtus tomentosa.

Alzheimer's diseases (AD) and other infectious diseases caused by drug-resistance bacteria have posed a serious threat to human lives and global health. With the aim to search for human acetylcholinesterase (hAChE) inhibitors and antibacterial agents from medicinal plants, 16 phloroglucinol oligomers, including two new phloroglucinol monomers (1a and 1b), four new phloroglucinol dimers (3a, 3b, 4b, and 5a), six new phloroglucinol trimers (6a, 6b, 7a, 7b, 8a, and 8b), and two naturally occurring phloroglucinol monomers (2a and 2b), along with two known congeners (4a and 5b), were purified from the leaves of tropic Rhodomyrtus tomentosa. The structures and absolute configurations of these new isolates were unequivocally established by comprehensive analyses of their spectroscopic data (NMR and HRESIMS), ECD calculation, and single crystal X-ray diffraction. Structurally, 3a/3b shared a rare C-5' formyl group, whereas 6a/6b possessed a unique C-7' aromatic ring. In addition, 7a/7b and 8a/8b were rare phloroglucinol trimers with a bis-furan and a C-6' hemiketal group. Pharmacologically, the mixture of 3a and 3b showed the most potent human acetylcholinesterase (hAChE) inhibitory activity with an IC50 value of 1.21 ± 0.16 µM. The molecular docking studies of 3a and 3b in the hAChE binding sites were performed, displaying good agreement with the in vitro inhibitory effects. In addition, the mixture of 3a and 3b displayed the most significant anti-MRSA (methicillin-resistant Staphylococcus aureus) with MIC and MBC values of both 0.50 µg/mL, and scanning electron microscope (SEM) studies revealed that they could destroy the biofilm structures of MRSA. The findings provide potential candidates for the further development of anti-AD and anti-bacterial agents.

Antifungal alkaloids from Mahonia fortunei against pathogens of postharvest fruit.

Postharvest pathogens can affect a wide range of fresh fruit and vegetables, including grapes, resulting in significant profit loss. Isoquinoline alkaloids of Mahonia fortunei, a Chinese herbal medicine, have been used to treat infectious microbes, which might be effective against postharvest pathogens. The phytochemical and bioactive investigation of this plant led to the isolation of 18 alkaloids, of which 9 compounds inhibited the growth of Botrytis cinerea and 4 compounds against Penicillium italicum. The antifungal alkaloids could change the mycelium morphology, the total lipid content, and leak the cell contents of B. cinerea. Furthermore, the two most potent antifungal alkaloids, berberine (13) completely inhibited effect on gray mold of table grape at 512 mg L-1, while jatrorrhizine (18) exhibited an inhibition rate > 90% on grape rot at the same concentration, with lower cytotoxicity and residue than chlorothalonil, which suggested that ingredients of M. fortunei might be a low-toxicity, low-residue, eco-friendly botanical fungicide against postharvest pathogens.

Phytochemical Analysis and Anti-Ascaris suum Activity of Different Zanthoxylum Species In Vitro and In Vivo.

Zanthoxylum plants (ZPs), including multiple Chinese prickly ash species, are dual-purpose functional foods favored by the general population around the world in foods, cosmetics, and traditional medicines and have antipruritic, insecticidal, and fungicidal bioactivities. For the first time, the anti-roundworm bioactivity of ZPs and the active ingredients were compared and investigated. Through nontarget metabolomics following targeted quantitative analysis, qinbunamides, sanshools, sanshooel, asarinin, and sesamin were found to be the main different components of Zanthoxylum species. Coincidentally, the 12 chemical components were also the dominant anti-roundworm ingredients of ZP extracts. The extracts of three species of Chinese prickly ash (1 mg/mL) decreased the hatchability of roundworm eggs significantly, and the ChuanJiao seed killed roundworms (insecticidal rate 100%) and alleviated the symptoms of pneumonia in mice. Furthermore, retention time-accurate mass-tandem mass spectrometry-ion ratio (RT-AM-MS/MS-IR) were modeled by assaying 108 authentic compounds of ZP extracts, and 20 metabolites were confidently identified in biological samples from ZP extract-treated mice by analyzing the m/z values and the empirical substructures. This study provides a good reference for the proper application of ZPs.

Steroidal alkaloid with unprecedented triheterocyclic architecture.

Veratrazine A (1), a steroidal alkaloid with a unique 6/5/5 triheterocyclic scaffold as the side chain, was isolated from Veratrum stenophyllum, and its structure was established via spectroscopic analyses and X-ray diffraction. A plausible biosynthetic pathway for 1 is proposed. Bioassy exhibits moderate anti-inflammatory activities in vitro and in vivo.

The Protective Effect of Sweet Potato Root Tuber on Chemotherapy-Induced Thrombocytopenia.

SCOPE: Sweet potato (Ipomoea batatas L.) is one of the leading crops worldwide, containing high nutritional components such as fiber and polyphenols. Root tuber of Simon 1 (SIMON), a cultivar of sweet potato, is a folk food in China with a hemostasis function but lacking experimental data support. METHODS AND RESULTS: Now the protective effect of SIMON on chemotherapy-induced thrombocytopenia (CIT), a serious complication of cancer treatment, is investigated for the first time by a CIT mouse model induced by intraperitoneal injection of carboplatin. As a result, SIMON raises the number of peripheral platelets, white blood cells, and bone marrow nucleated cells in CIT mice significantly. Besides, carboplatin-induced atrophy of the thymus, spleen, and disordered metabolism of the inflammatory immune system and glycerophospholipids are also reversed by SIMON. Phytochemical analysis of SIMON indicates 16 compounds including eight phenolic derivatives, which might be associated with its anti-CIT bioactivity. CONCLUSION: Sweet potato (SIMON) may be an efficient function food in the prevention of bleeding disorders.

New steroidal alkaloids with anti-inflammatory and analgesic effects from Veratrum grandiflorum.

ETHNOPHARMACOLOGICAL RELEVANCE: "Li-Lu", the roots and rhizomes of Veratrum grandiflorum (Melianthiaceae), has been historically used as a traditional folk medicine for the treatment of wrist pain, fractures, sores, and inflammation in Yunnan Province, China. However, the anti-inflammatory and analgesic studies of this plant have seldom reported. AIM OF THE STUDY: To evaluate the anti-inflammatory and analgesic properties related to the traditional usage of V. grandiflorum both in vitro and in vivo, and further explore the accurate bioactive compounds from the medicinal plant. MATERIALS AND METHODS: Phytochemical investigation was carried out by chromatographic methods and their structures were established based on extensive spectra and comparison with corresponding data in the reported literatures. Anti-inflammatory activities were assessed by the suppression of lipopolysaccharide-activated inflammatory mediators in RAW 264.7 macrophage cells in vitro. Furthermore, anti-inflammatory and analgesic effects were evaluated based on carrageenan-induced paw edema and acetic acid-stimulated writhing in mice. RESULTS: The methanol extract (ME) of V. grandiflorum significantly alleviated the paw edema caused by carrageenan and the writhing numbers induced by acetic acid. Subsequent phytochemical investigation led to isolated of 21 steroidal alkaloids, including seven new compounds, veragranines C-I (1-7). Anti-inflammatory test indicated that steroidal alkaloids could decrease the expression of cyclooxygenase-2 (COX-2), interleukin-1ß (IL-1ß), and tumor necrosis factor α (TNF-α) in lipopolysaccharide (LPS)-stimulated RAW 264.7 macrophage cells at a concentration of 5.0 µg/ml in vitro, comparable to DXM. Moreover, five new steroidal alkaloids (2, 4, 5, 6, and 7) and two major steroidal alkaloids (9 and 13) significantly decreased the numbers of writhing in mice at the doses of 0.5 and/or 1.0 mg/kg (p < 0.01/0.05), roughly comparable to Dolantin™ at 10.0 mg/kg. CONCLUSIONS: The investigation supported the traditional use of V. grandiflorum and provided new steroidal alkaloids as potent analgesic agents.

Phytochemical and Antibacterial Constituents of Edible Globe Amaranth Flower against Pseudomonas aeruginosa.

Globe amaranth flower, the edible inflorescence of Gomphrena globose L., was used to treat dysentery and ulcer as well as other infectious diseases caused by microbes in Southwest China, but its function and bioactive components need experimental support. In this study, phytochemical constituents and antibacterial bioactivity of globe amaranth flower against P. aeruginosa were carried out. As a result, two new (1 and 2) and eleven known (3-11) compounds were isolated, in which compounds 4-7 displayed anti P. aeruginosa bioactivity with the minimum inhibitory concentration (MIC) from 0.008 to 0.256 mg/mL. Furthermore, with aid of the scanning electron microscope (SEM) and a superficial skin infection model in mice, the most potent compound 4 can significantly destroy the structure of bacteria in vitro and restore bacterial infection damage in vivo.

Phytochemical and anti-MRSA constituents of Zanthoxylum nitidum.

Infectious diseases caused by multidrug-resistant bacteria such as methicillin-resistant Staphylococcus aureus, pose a significant threat to humanity. Persistent and repeated invasive infection with MRSA led to higher morbidity and mortality, and required comprehensive measures in treatment and prevention. Zanthoxylum nitidum (Roxb.) DC. is used as detoxifying, analgesic, and hemostatic herbal medicine for thousands of years. Previously pharmacological studies showed that Z. nitidum had antibacterial bioactivity, but only the MIC of a few compounds, crude extracts, and fractions were reported. In our ongoing endeavor to explore bioactive compounds, two new coumarins, 6-(3-oxo-butyl)-limettin (1) and toddalin I (2), and 24 known compounds were isolated from the roots of Z. nitidum, in which two isoquinoline alkaloids, 6-acetonyl-dihydrofagaridine (16) and 6-acetonyl-dihydrochelerythrine (17) showed anti-MRSA bioactivity in vitro and in vivo. Both 16 and 17 showed synergistic action with ampicillin, which decreased the MIC significantly, and both compounds had a significant ability to destroy bacterial biofilm combined with ampicillin. The combined administration showed a strong scavenging effect on the planktonic bacteria in vitro and cleared skin infection effectively in the model of wound infection in vivo. Furthermore, compound 16 inhibited the efflux of the drug by combining with ampicillin or EtBr, resulting in the MIC decreased obviously. Our investigation supported the traditional use of Z. nitidum in treating infections caused by bacteria, and might provide new natural products to reduce the use of antibiotics and the treatment of drug-resistance bacteria.

Bioguided isolation, identification and bioactivity evaluation of anti-MRSA constituents from Morus alba Linn.

ETHNOPHARMACOLOGY RELEVANCE: The root bark of Morus alba Linn. (M. alba), a traditional folk medicine, has been documented in the Chinese Pharmacopoeia, which has been widely used for asthma, fever, pneumonia, edema, vomit, colitis, bronchitis and keratitis diseases. Some of the diseases may be related to respiratory, digestive, urinary tract infections. Although Diels-Alder adducts (DAAs), flavonoids, 2-arylbenzofurans and stilbene compounds have been isolated from the root bark of M. alba, few compounds are reported for their antimicrobial efficacy in vivo and the mechanism. AIM OF THE STUDY: The aim of the study was to isolate and identify compounds of the root bark of M. alba in view of their anti-MRSA bioactivity, evaluate the anti-MRSA bioactivity of compounds and 60% ethanol elution (MA-6) in vitro and in vivo, and explore preliminary antibacterial mechanism in order to provide natural resources against MRSA infection. MATERIALS AND METHODS: Systematic phytochemical investigations were carried out according to the thin layer chromatography (TLC) of the active fraction MA-6 to find more anti-MRSA ingredients. The compounds of the root bark of M. alba were separated by column chromatography and identified by LC-MS/MS and NMR spectroscopy. The anti-MRSA efficacy of the active ingredients were evaluated by broth microdilution method and a murine infection model. The mode of action of compounds was explored by time-kill curve and post-contact effect. The preliminary mechanism of compounds against MRSA was explored by drug efflux pumps and bacterial biofilms. RESULTS: Chemical isolation resulted in twenty-nine known compounds, most with one or more geranyl and prenyl units exhibited superior anti-MRSA bioactivity, with MIC values of 2-16 µg/mL. In addition, the mode of action indicated that compounds presented persistent antimicrobial effect, which also produced concentration-dependent and time-dependent killing activity or property. Preliminary mechanism showed that the compound kuwanon O (29) damaged the bacterial cell membranes, leading to the accumulation of antibiotics inside bacterial cells, moreover, MA-6 and kuwanon O (29) inhibited the efflux of drugs by combining with methicillin or ethidium bromide (EtBr), resulting in the MICs of EtBr and methicillin were obviously decreased three-fold. The anti-MRSA efficacy in vivo indicated that the active fraction MA-6 could reduce bacteria in spleen, liver, kidney and mortality of acutely infectious mice, which was better than the positive drug berberine chloride. CONCLUSION: Experimental investigation showed that the MA-6 and compound 29 have promising bioactivity against MRSA in vitro and in vivo, which might be used as a potential source of new antibacterial medicine or a potential efflux pump inhibitor against MRSA infection.

Bioactivity Ingredients of Chaenomeles speciosa against Microbes: Characterization by LC-MS and Activity Evaluation.

Chaenomeles speciosa (Sweet) Nakai is a dual-purpose Chinese herbal medicine and functional food favored by minorities in Southwest China, and its fruits are used for the treatment of dyspepsia, dysentery, enteritis, and rheumatism inflammation. Some diseases may be related to microbial infection; however, it is not known how the fruits possess antimicrobial activity. We evaluated the antimicrobial bioctivity of different evaluation extracts of C. speciosa fruits by in vitro and in vivo with colony-forming unit assays, and the strongest bioactive-guided fraction was selected for column chromatography (CC), UHPLC-QTOF-MS/MS, and NMR spectroscopy to confirm the chemical constituents. The most possible antimicrobial mechanism of C. speciosa fruits was explored by metabolomics approach, fluorescence microscopy imaging, and scanning electron microscopy (SEM). Thirty compounds, which were major characteristic ions of the bioactive fraction, were determined precisely. The bioactive fraction could inhibit 18 pathogenic microorganisms, significantly reduced, especially drug-resistant bacteria, compared to ampicillin sodium salt, fluconazole, and berberine chloride form; and the minimum inhibitory concentration (MIC) or minimum fungicidal concentration (MFC) values were in the range of 0.1-1 mg/mL. The compounds 2'-methoxyaucuparin (1) and oleanolic acid (20) not only have antibacterial activity but also may have synergistic effects. Further, the bioactive fraction might inhibit the biofilm formation, enhance immunity, and restore bacterial infection damage in vitro and in vivo to kill microorganisms. The data indicated that C. speciosa fruits' major bioactive fraction enriched with triterpenes, flavonoids, and phenolics could be developed as a functional supplement for individuals to prevent and treat microbial infection.

A review of plant characteristics, phytochemistry and bioactivities of the genus Glechoma.

ETHNOPHARMACOLOGICAL RELEVANCE: Plants of the genus Glechoma have been abundantly used for thousands of years in China as folk treatments for cholelithiasis, urolithiasis, inflammation, and other conditions. AIM OF THE STUDY: This review discusses the potential application of Glechoma as an herbal medicine. The plant characteristics, ethnobotanical uses, phytochemistry, and pharmacological activities of Glechoma are summarized as a guide for phytochemical and pharmacological investigations. MATERIALS AND METHODS: Various search engines including SciFinder, Google Scholar, Scopus-Elsevier, Medline, Web of Science, and China National Knowledge Infrastructure were searched for publications on Glechoma using relevant keywords. Additionally, local records, books, and non-English journals were screened up to October 2020. RESULTS: The phytochemistry of several Glechoma plants has been systematically studied, and over one hundred different compounds have been isolated and identified. Terpenoids, flavonoids and polyphenols are the major secondary metabolites. Crude extracts and isolated compounds have been shown to exhibit various pharmacological activities including prevention of nephrolithiasis, anti-inflammatory, analgesic, anticomplement, antimicrobial, antioxidant, depigmenting, anticancer, and antiviral activities, among others. CONCLUSION: Glechoma species have been used as folk medicine to treat various diseases and have diverse biological activities, making them valuable starting materials for drug development. However, in most cases the pharmacological mechanisms, pharmacokinetics, toxicology, safety, and possible interactions with other drugs remain to be determined.

Neothalfine, a potent natural anti-tumor agent against metastatic colorectal cancer and its primary mechanism.

Neothalfine is a natural bisbenzylisoquinoline alkaloid with the abundant resource in medicinal plants and has not been reported its anti-tumor efficacy. In the present study, the anti-tumor efficacy was investigated and it showed broad-spectrum activity against several cancer cell lines, especially metastatic colorectal cancer (HCT116, SW620, T84) with the IC50 values of 7.2, 5.9, 8.2 nM, respectively, roughly equal to well-known anti-tumor agent docetaxel (4.0, 4.7, 2.7 nM) and nearly 1000 folds than CPT-11 (4.4, 5.1, 6.9 µM). Furthermore, neothalfine inhibited colorectal cell proliferation by resulting in cell cycle arrest at the G2/M phase and induced apoptosis through the dysfunction of mitochondria to trigger intrinsic apoptotic pathway by untargeted metabolomic method, mitochondrial membrane potential, and caspase-3/7 activity assay. Moreover, neothalfine damaged colorectal cancer clonal spheres expansion significantly at the concentration of 3.5 nM with nearly 1000 folds efficacy than CPT-11 (3.0 µM). The results supported that neothalfine might be an anti-tumor lead for further investigation.

Bioguided isolation, identification and activity evaluation of antifungal compounds from Acorus tatarinowii Schott.

ETHNOPHARMACOLOGY RELEVANCE: As a traditional folk medicine, Acorus tatarinowii Schott was used to treat digestive diseases, such as diarrhea, which may be related to Candida albicans infection; however according to literature surveys, there have been few studies of A. tatarinowii focusing on its antimicrobial activity, and almost all describe investigations using crude extracts or fractions. AIM OF THE STUDY: The aims of the current study were to isolate and identify antifungal fractions of A. tatarinowii based on their antifungal activity, explore the preliminary mechanism of 60% ethanol elution (AT60) by metabonomics, and evaluate the antifungal activity of AT60 in vivo and in vitro, to provide natural resources against fungal infections. MATERIALS AND METHODS: As a pilot evaluation of activity, A. tatarinowii fractions and compounds with antifungal bioactivity were isolated by bioactive-guided column chromatography, and identified by LC-QTOF-MS/MS and NMR spectroscopy. The antifungal effects of the active ingredients against resistant C. albicans were evaluated by in vivo and in vitro colony forming unit assays. The mechanism underlying the activity of AT60 against C. albicans was explored using an LC-QTOF-based metabonomics approach and fluorescence microscopy imaging. RESULTS: AT60 showed better activity against C. albicans than the same dose of the first line antifungal drugs, fluconazole and itraconazole (positive control drugs). Subsequent phytochemical investigation of AT60 identified twenty-five known compounds, six of which were isolated: asaraldehyde (7), 1-(2,4,5-trimethoxyphenyl)-1,2-propanediol (12), α-asarone (14), ß-asarone (15), γ-asarone (18), acotatarone C (19). Further, the compounds α-asarone (14) and acotatarone C (19) may be responsible for the antifungal activity, and exhibit synergistic effects. Metabonomics analysis indicated that AT60 can inhibit biofilm formation by regulating the C. albicans protein kinase C pathway. CONCLUSIONS: Our results show that A. tatarinowii has potent bioactivity against C. albicans in vitro and in vivo, and can be considered an antifungal botanic agent.

Comparative investigation of phytochemicals among ten citrus herbs by ultra high performance liquid chromatography coupled with electrospray ionization quadrupole time-of-flight mass spectrometry and evaluation of their antioxidant properties.

The citrus herbs have proved their important medicinal and nutritional values as medicine-food dual-purpose herbs, functional foods, or medical herbs in China. In this study, phytochemicals and antioxidant activity among ten typical citrus herbs (ethanol extracts) were investigated comprehensively. The major ingredients and their contents were analyzed by high-resolution mass spectrometry, and the differences of typical fragment ions between flavanone-7-O-rutinoside(s) and flavanone-7-O-neohesperidoside(s) were discriminated properly in negative electrospray ionization mode. Total polyphenols, total flavonoids, 1,1-diphenyl-2-picrylhydrazyl, 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid), and ferric reducing antioxidant power tests were performed, which indicated their beneficial values and antioxidant effects. The medicine-food dual-purpose herbs including Chenpi, Juluo, Daidaihua, Huajuhong, Xiangyuan, and Foshou exhibited antioxidant capacities significantly by decreasing intracellular reactive oxygen species intensity (P < 0.01), enhancing superoxide dismutase, catalase, and glutathione peroxidase activities (P < 0.01) in H2 O2 -induced RIN-m5F cells. Moreover, the functional foods Zhishi, Zhiqiao, and Qingpi showed moderate antioxidant bioactivity, while the medical herb Juhe showed weak antioxidant bioactivity, which were consistent with the multivariate analysis of their major flavonoids. The study provided a new sight for the chemical differentiation and practical application of citrus herbs as medicine-food dual-purpose herbs, functional foods, or medical herbs.