[Advances on cyclopeptides of plants].

Cyclopeptides isolated from a variety of plants are a class of cyclic nitrogen-containing compounds, and they are primarily formed by peptide bonds between amino acids, generally containing 2 to 37 L-configuration encoded or non-encoded amino acid residues. Cyclopeptides have significant values in scientific research as natural small-molecule metabolites produced by plants. The available studies have revealed that such natural products are ubiquitous in plants, which mainly include cyclic dipeptides, cyclic tetrapeptides, cyclic pentapeptides, cyclic hexapeptides, cyclic heptapeptides, cyclic octapeptides, cyclic nonapeptides, and cyclic decapeptides. Among them, cyclic dipeptides, cyclic hexapeptides, and cyclic octapeptides are the major active compounds. It has been reported that plant cyclopeptides have novel and unique chemical structures. They possess diverse pharmacological activities, such as antineoplastic, antimicrobial, antimalarial, anti-inflammatory, and antiviral activities. This paper summarizes the research achievements of plant cyclopeptides since 2006, aiming to provide theoretical reference for the research and application of plant cyclopeptides in medicine, health, and agriculture fields.

Accumulation of antitumor polyketides by fermentation of Rubus delavayi Franch. with Clonostachys rogersoniana.

The aim of this work is to explore the effects of herbal medicine on secondary metabolites of microorganisms during fermentation. Clonostachys rogersoniana was found to metabolize only small amounts of polyketide glycosides rogerson B and C on fresh potatoes, but after replacing the medium to the medicinal plant Rubus delavayi Franch., the type and content of the metabolized polyketones showed significant changes. The sugars and glycosides in R. delavayi are probably responsible for the changes in secondary metabolites. Six polyketide glycosides including a new metabolite, rogerson F, and two potential antitumor compounds, TMC-151C and TMC-151D, were isolated from the extract of R. delavayi fermented by C. rogersoniana. In addition, 13C labeling experiments were used to trace the biosynthesis process of these compounds. TMC-151C and TMC-151D showed significant cytotoxic activity against PANC-1, K562 and HCT116 cancer cells but had no obvious cytotoxic activity against BEAS-2B human normal lung epithelial cells. The yields of TMC-151C and TMC-151D reached 14.37 ± 1.52 g/kg and 1.98 ± 0.43 g/kg, respectively, after fermentation at 28 °C for 30 days. This is the first study to confirm that herbal medicine can induce microbes to metabolize active compounds. And the technology of fermenting medicinal materials can bring more economic value to medicinal plants.

A new C19-diterpenoid alkaloid in Aconitum georgei Comber.

Nine diterpenoid alkaloids were isolated from Aconitum georgei Comber belonging to the genus Aconitum in Ranunculaceae family. Their structures were determinated by using HR-ESI-MS and 1 D/2D NMR spectra as geordine (1), yunaconitine (2), chasmanine (3), crassicauline A (4), forestine (5), pseudaconine (6), 14-acetylalatisamine (7), austroconitine B (8), and talatisamine (9). Among them, compound 1 is a previously undescribed aconitine-type C19-diterpenoid alkaloid, and compounds 3, and 5-9 have not previously been isolated from this species. The results of in vitro experiments indicated that new compound 1 possesses mild anti-inflammatory activity, which inhibited the production of NO in LPS-activated RAW 264.7 cells with an inhibition ratio of 29.75% at 50 µM.

The antifungal metabolites isolated from maize endophytic fungus Fusarium sp. induced by OSMAC strategy.

Six new sesquiterpenes, fusarchlamols A-F (1, 2, 4-7); one new natural product of sesquiterpenoid, methyltricinonoate (3); and ten known compounds were found from Fusarium sp. cultured in two different media by the one strain many compounds strategy. The compounds (1, 2, and 4-11) were isolated from Fusarium sp. in PDB medium, and compounds (3-5, 8, and 10-17) were discovered from Fusarium sp. in coffee medium. Additionally, the configuration of 8 was first reported in the research by Mosher's method. The structures were established by 1D, 2D NMR, mass spectrometry, calculated ECD spectra, and Mosher's method. Compounds 1, 2, 6/7, 12, and 16 indicated significant antifungal activities against the phytopathogen Alternaria alternata isolated from Coffea arabica with MICs of 1 µg/mL. The investigation on the anti-phytopathogen activity of metabolites can provide lead compounds for agrochemicals.

Guided isolation of secondary metabolites from Nectria sp. MHHJ-3 by molecular network strategy.

The fungus Nectria sp. MHHJ-3 was isolated from Illigera rhodantha. A molecular networking-guided the secondary metabolites investigation of Nectria sp. MHHJ-3 led to the isolation of ten metabolites (1-10), including two new naphthalenone derivatives, nectrianaphthalenones A (1) and B (2), and two new steroids, nectriasteroids A (3) and B (4). Their structures were elucidated by extensive spectroscopic analysis including the HRESIMS, 1D/2D NMR and electronic circular dichroism (ECD) spectra. A plausible biosynthetic pathway for 1-2 was proposed. Compounds 1 and 2 exhibited moderate acetylcholinesterase (AChE) inhibitory activities. Compounds 3 and 4 showed significant cytotoxic activity against selected tumor cells. Particularly, compound 3 exhibited the strongest activity against A549 cells with an IC50 value of 13.73 ± 0.03 µM, which was at the same grade with that of positive control cisplatin.

Steroids and dihydroisocoumarin glycosides from Xylaria sp. by the one strain many compounds strategy and their bioactivities.

The fungus Xylaria sp. KYJ-15 was isolated from Illigera celebica. Based on the one strain many compounds (OSMAC) strategy, the strain was fermented on potato and rice solid media, respectively. As a result, two novel steroids, xylarsteroids A (1) and B (2), which are the first examples of C28-steroid with an unusual ß- and γ-lactone ring, respectively, along with two new dihydroisocoumarin glycosides, xylarglycosides A (3) and B (4), were identified. Their structures were elucidated by spectroscopic methods, X-ray diffraction and electronic circular dichroism (ECD) experiments. All isolated compounds were evaluated for cytotoxicity, DPPH radical scavenging activity, acetylcholinesterase inhibitory and antimicrobial effect. Compound 1 exhibited potent AChE inhibitory activity with an IC50 value of 2.61 ± 0.05 µmol·L-1. The ß-lactone ring unit of 1 is critical for its AChE inhibitory activity. The finding was further confirmed through exploring the interaction of 1 with AChE by molecular docking. In addition, both compounds 1 and 2 exhibited obvious antibacterial activity against Bacillus subtilis with a minimum inhibitory concentration (MIC) of 2 µg·mL-1. Compounds 3 and 4 exhibited antibacterial activities against Staphylococcus aureus with MICs of 4 and 2 µg·mL-1, respectively, which also exhibited DPPH radical scavenging activity comparable to the positive control with IC50 values of 9.2 ± 0.03 and 13.3 ± 0.01 µmol·L-1, respectively.

Macrostines A and B: Tetracyclic fisicoccane from the fungus Periconia macrospinosa WTG-10.

Two previous unreported fusicoccane diterpenoids macrostines A and B, together with seven known compounds were isolated from an extract of the fungus Periconia macrospinosa WTG-10. Their structures were elucidated by detailed analysis of spectroscopic data, NMR calculations with DP4+, and their absolute configurations were further determined by quantum chemical calculations of ECD spectra or X-crystallography. Macrostines A and B showed no cytotoxicity, antimicrobial activity and inhibitory effect on nitric oxide production in LPS-activated RAW264.7 macrophages. Compound 9 showed moderate activity against Bacillus subtilis.

Phytotoxic meroterpenoids with herbicidal activities from the phytopathogenic fungus Pseudopestalotiopsis theae.

The fungus Pseudopestalotiopsis theae isolated from the fresh leaves of Illigera celebica, has been reported to be a pathogenic fungus that can cause gray blight on tea leaves, a disease characterized by the appearance of necrotic lesions on tea leaves. The pathogenic substances in this fungus have not been clearly identified. Considering the possible involvement of specialized metabolites in symptom appearance, a chemical investigation of specialized metabolites on P. theae was conducted, resulting in the isolation of eight meroterpenoids, including six undescribed biscognienynes G-L and two known ones (biscognienynes B and D). The structures of these new compounds were characterized by extensive NMR spectroscopic and HR-ESI-MS data, and their absolute configurations were elucidated by ECD calculations. Except for biscogniyne L, all the isolated biscognienynes showed different degrees of phytotoxicity to tea in vivo, thereby revealing for the first time the substances in P. theae that cause tea gray blight. Inspired by the fact that phytotoxins produced by pathogenic fungus are an effective resource for designing natural and safe bioherbicides, when assayed the herbicidal activity through Petri dish bioassays, biscognienynes G-J showed phytotoxic effects against seed germination and seedling growth of Setaria viridis, strongly inhibiting seed germination percentage and radicle and germ lengths of seedlings. The results of this study demonstrated the great potential of biscognienynes G-J to be proposed and developed as ecofriendly herbicides.

Similarities and differences between China and Sweden regarding the core features of palliative care for people aged 60 or older: a systematic scoping review.

BACKGROUND: Despite the increasing longevity of the world's population, with an unprecedented rise in the number of people who need palliative care (PC), there has been sparse research regarding palliative care for older people, especially when it comes to comparison of PC between healthcare systems and cultures. The aim of this systematic scoping review was to identify the characteristics of the body of literature and to examine the knowledge gaps concerning PC research for older people (> 60 years) in two healthcare systems and cultures, mainland China and Sweden. METHODS: The guidelines PRISMA (Preferred Reporting Items for Systematic Reviews), and PICOS (Patient/population, Intervention, Comparison/control, and Outcome) were used. Empirical studies on patients 60 years or older, next of kin or staff participating in a palliative care intervention or setting were included. They were conducted in mainland China or in Sweden during 2007-2019, were published in English and were extracted from seven databases: Embase, PubMed, Scopus, Cinahl, PsycInfo, Academic Search Complete and Cochrane Library. Two independent researchers conducted the selection of studies, data extraction and methodological evaluation. Any disagreements were resolved in consultation with a third researcher. The analysis was manifest directed content analysis based on PICOS domains. RESULTS: Of the 15 studies, four were from mainland China and 11 from Sweden. Both countries included older patients with cancer but also other end-stage diseases such as heart failure and dementia. The studies differed in design, method and the content of the interventions. The study in China based on traditional Chinese medicine concerns traditional Chinese folk music. The six qualitative studies from Sweden were evaluations of five interventions. CONCLUSIONS: Despite the high age of the participating patients, there was no focus on an ageing perspective concerning palliative care. To adapt to the changes taking place in most societies, future research should have increased focus on older persons' need for palliative care and should take account of issues concerning research ethics, ethnicity and culture. REGISTERED IN PROSPERO: CRD42020078685 , available from.

Four new phenanthrene derivatives from Bulbophyllum retusiusculum.

Three new dihydrophenanthrenes, retusiusine D (1), retusiusine E (2), retusiusine F (3), and a new phenanthrene retusiusine G (4), together with two known dihydrophenanthrenes 4,7-dihydroxy-2,3-methylenedioxy-9,10-dihydrophenanthrene (5) and epemeranthol-A (6) were isolated from the tubers of Bulbophyllum retusiusculum. Their structures were established on the basis of extensive spectroscopic analyses. Compounds 1 and 2 exhibited potent cytotoxic activities against SMMC-7721 and weak cytotoxic activities against HL-60. Compound 4 showed moderate cytotoxic activity against SMMC-7721 and MCF-7.

Nagarines A and B, two novel 8,15-seco diterpenoid alkaloids from Aconitum nagarum.

Two novel 8,15-seco C19-diterpenoid alkaloids, nagarines A (1) and B (2), were isolated from the roots of Aconitum nagarum Stapf (Ranunculaceae), a folk herbal medicine used to treat rheumatism and arthritis in Southwestern China, Northern Burma and Northeastern India. They are the first C19-diterpenoid alkaloids possessing unprecedented opened D ring formed by the cleavage of the bond between C-8 and C-15. Compounds 1 and 2 showed certain inhibition activities of interleukin-6 in LPS-activated RAW 264.7 cells with IC50 values of 72.63 ±â€¯0.39 µM and 52.98 ±â€¯0.50 µM, respectively.

Non-alkaloidal constituents from the genus Aconitum: a review.

Species of the genus Aconitum are widely distributed in the north temperate region and have been used in traditional medicine since antiquity due to their biological activities. Phytochemical investigations of Aconitum species have revealed the presence of multiple active ingredients, including flavonoids, phenylpropanoids, phenolics and acids, terpenoids, and polysaccharides in addition to their diterpenoid alkaloids. These non-alkaloidal constituents show great research significance for their novel structures, broad bioactivities, and chemotaxonomical significance. This review addresses, for the first time, the non-alkaloidal constituents and their biological properties and their taxonomic significance for Aconitum plants to facilitate future research.

Three new diterpenoid alkaloids isolated from Aconitum brevicalcaratum.

In the present study, three new aconitine-type diterpenoid alkaloids brochyponines A-C (1-3) were isolated from the roots of Aconitum brevicalcaratum. Their structures were established on the basis of extensive spectroscopic analyses (IR, HR-ESI-MS, and 1D and 2D NMR). The NMR data of salt form for compound 1 in CDCl3 were also measured.

New phenylpropanoids from Bulbophyllum retusiusculum.

Two new phenylpropanoids, retusiusines A (1) and B (2), and a pair of new phenylpropyl enantiomers, (±)-retusiusine C (3a and 3b), together with eight known compounds, dihydroconiferyl dihydro-p-coumarate (4), methyl 3-(4-hydroxyphenyl) propionate (5), 3-(4-hydroxyphenyl)-propanoic acid (6), dihydroferulic acid (7), methyl 3-(4-methoxyphenyl) propionate (8), 3-(3,4-dimethoxyphenyl)-2-propenal (9), trans-p-coumaric acid (10) and dihydroconiferyl alcohol (11), were isolated from the tubers of Bulbophyllum retusiusculum. The absolute configurations of the new compounds were determined by calculating their electronic circular dichroism (ECD), spectra and specific optical rotations and comparing the calculated values with the experimental data. Compound 2 exhibited potent antifungal activity against Candida albicans (16 µg/mL). Compound 3 showed moderate antibacterial activity against Bacillus subtilis (64 µg/mL).

Simultaneous determination of alkaloids dicentrine and sinomenine in Stephania epigeae by 1H NMR spectroscopy.

Stephania epigaea Lo is an important herbal medicine used as antiphlogistic and analgesic drugs. Its major components are dicentrine (1) and sinomenine (2). In the present study, a rapid, accurate, and precise method for simultaneous quantitation of dicentrine (1) and sinomenine (2) in S. epigeae using 1H NMR spectra was developed. The deuterated solvent of DMSO-d6 enabled satisfactory separation of the signals to be integrated in 1H NMR spectrum and dimethyl terephthalate was selected as an internal standard. The feature signals of δ 7.57 and 5.70 were selected for quantifying the dicentrine (1) and sinomenine (2), respectively. Validation of the quantitative method was performed in terms of specificity, accuracy, precision, and stability. This work implied that quantitative 1H NMR represents a feasible alternative to high-performance liquid chromatography-based methods for quantitation of dicentrine (1) and sinomenine (2) in S. epigeae and is suitable for the quality control of S. epigeae.

A novel sesquiterpene derivative with a seven-membered B ring from Illigera aromatica.

A novel sesquiterpene derivative with a seven-membered B ring, illigerine (1), along with four known compounds, 1-epi-chiliophyllin (2), 3,4-dihydroxyphenethyl alcohol (3), coniferyl alcohol (4) and phenylpropionic acid (5), were isolated from Illigera aromatica S. Z. Huang et S. L. Mo. Their structures were identified by 1D/2D NMR, HRESIMS and electronic circular dichroism spectra and the cytotoxic activity and inhibitory effect of NO production in LPS-stimulated RAW264.7 were also evaluated. This is the first report of sesquiterpene isolated from the genus Illigera.

Cytotoxicity of the Defensive Secretion from the Medicinal Insect Blaps rynchopetera.

Blaps rynchopetera Fairmaire has long been used as a folk medicine by the Yi and Bai ethnic groups in China to treat fever, cough, gastritis, boils, and tumors. In the present study, the cytotoxicity of the defensive secretion (TDS) of B. rynchopetera against AGS Caco-2, HepG2 U251 and Bel-7402 was tested, and the results revealed that TDS had potent cytotoxicity against testing cells with IC50 values of 45.8, 17.4, 53.6, 98.4 and 23.4 µg/mL, respectively. Gas chromatography-mass spectrometry (GC-MS) analysis was employed to clarify the cytotoxic constituents in TDS of B. rynchopetera and five volatile compounds, including 2-ethyl-2,5-cyclohexadiene-1,4-dione (3, 31.00%), 1-tridecene (5, 28.02%), 2-methyl-2,5-cyclohexadiene-1,4-dione (2, 22.86%), hydroquinone (4, 1.33%), and p-benzoquinone (1, 1.01%), were identified. Chemical constituent investigation on TDS further supported the presence of 5 above compounds. A cytotoxic assay indicated that compounds 1, 2, 3 and 4 exhibited significant cytotoxicity against the testing cell lines, implying that benzoquinones and hydroquinone played important roles in the cytotoxicity of TDS of B. rynchopetera. TDS is a cytotoxic natural material and further studies investigating mechanisms and inhibitory activities on other cell lines is warranted.

Improving the acetylcholinesterase inhibitory effect of Illigera henryi by solid-state fermentation with Clonostachys rogersoniana.

Illigera henryi, an endemic traditional Chinese medicine, contains abundant aporphine alkaloids that possess various bioactivities. In the present study, tubers of I. henryi were fermented by several fungi, and the acetylcholinesterase (AChE) inhibitory activities of non-fermented and fermented I. henryi were measured. The results showed that the fermentation of I. henryi with Clonostachys rogersoniana 828H2 is effective for improving the AChE inhibitory activity. A key biotransformation was found during the C. rogersoniana fermentation for clarifying the improvement of the AChE inhibitory activity of I. henryi: (S)-actinodaphnine (1) was converted to a new 4-hydroxyaporphine alkaloid (4R,6aS)-4-hydroxyactinodaphnine (2) that possessed a stronger AChE inhibitory activity, with an IC50 value of 17.66±0.06 µM. This paper is the first to report that the pure strain fermentation processing of I. henryi and indicated C. rogersoniana fermentation might be a potential processing method for I. henryi.

Effect of Electroacupuncture at The Zusanli Point (Stomach-36) on Dorsal Random Pattern Skin Flap Survival in a Rat Model.

BACKGROUND: Random skin flaps are commonly used for wound repair and reconstruction. Electroacupuncture at The Zusanli point could enhance microcirculation and blood perfusion in random skin flaps. OBJECTIVE: To determine whether electroacupuncture at The Zusanli point can improve the survival of random skin flaps in a rat model. MATERIALS AND METHODS: Thirty-six male Sprague Dawley rats were randomly divided into 3 groups: control group (no electroacupuncture), Group A (electroacupuncture at a nonacupoint near The Zusanli point), and Group B (electroacupuncture at The Zusanli point). McFarlane flaps were established. On postoperative Day 2, malondialdehyde (MDA) and superoxide dismutase were detected. The flap survival rate was evaluated, inflammation was examined in hematoxylin and eosin-stained slices, and the expression of vascular endothelial growth factor (VEGF) was measured immunohistochemically on Day 7. RESULTS: The mean survival area of the flaps in Group B was significantly larger than that in the control group and Group A. Superoxide dismutase activity and VEGF expression level were significantly higher in Group B than those in the control group and Group A, whereas MDA and inflammation levels in Group B were significantly lower than those in the other 2 groups. CONCLUSION: Electroacupuncture at The Zusanli point can effectively improve the random flap survival.

Monoterpene esters and aporphine alkaloids from Illigera aromatica with inhibitory effects against cholinesterase and NO production in LPS-stimulated RAW264.7 macrophages.

Three new monoterpene phenylpropionic acid esters, illigerates A-C (1-3), and one new aporphine alkaloid, illigeranine (4), as well as four known ones, actinodaphnine (5), nordicentrine (6), 8-hydroxy carvacrol (7), and 3-hydroxy-α,4-dimethyl styrene (8), were isolated from the tubers of Illigera aromatica. The structures of 1-4 were identified by HRESIMS, 1D and 2D NMR, and electronic circular dichroism spectra. Compound 1 potently inhibited NO production in LPS-stimulated RAW264.7 cells with an IC50 value of 18.71 ± 0.85 µM; compound 1, 3, and 4 showed moderate butyrylcholinesterase inhibitory activities with the IC50 values of 46.86 ± 0.65, 53.51 ± 0.71, and 31.62 ± 1.15 µM, respectively. Compound 4 showed weak AChE inhibitory activity with an IC50 value of 81.69 ± 2.07 µM, and compounds 5 and 6 possessed moderate AChE inhibitory activities with the IC50 values of 47.74 ± 1.66 and 40.28 ± 2.73 µM, respectively. This paper provides a chemical structure and bioactive foundation for using I. aromatica as an herbal medicine.