[Two pairs of phloroglucinol enantiomers from Hypericum wightianum and their stereochemical structures].

The chemical constituents in the ethanol extract of Hypericum wightianum(Hypericaceae) were purified by column chromatography and identified via magnetic resonance imaging(NMR), high-resolution mass spectrum, and circular dichroism. A total of 22 compounds were identified, including eight polyprenylated phloroglucinols(1-8), three chromones(9-11), and three terpenoids(14-16) and so on. Among them, compounds 16 and 17 were first reported in the genus Hypericum, and compounds 1-11, 14, 15, and 19 were first isolated from H. wightianum. Compounds 1-4 were previously reported as two pairs of enantiomers. This study reported the chiral resolutions and absolute configurations of compounds 1-4 for the first time.

[Traditional medicinal knowledge in Lancang-Mekong River:a case study in Lancang Lahu autonomous county].

Lancang Lahu autonomous county, where the Lancang-Mekong River flows by, was selected as the case site to investigate the traditional medicinal knowledge(TMK). A comparison of TMK between Lancang county and other places in the Lancang-Mekong sub-region was conducted. Research on TMK has been seldom reported although there are abundant medicinal resources in this sub-region. The key informant interview and other methods have been adopted in the field surveys in the past six years. The investigation revealed that there was rich TMK and various herbal medicine resources in Lancang county. A total of 220 folk prescriptions have been collected, which were normally simple with easy processing methods and usages, and most raw materials were freshly used. As for medicinal plants, 121 species in 67 families have been documented. Other findings included that TMK in Lancang county was remained at the level of medication based on experience only. The processing methods of herbal medicines were simple and the bioactive ingredients were not clear. Without text and cultural support for self-teaching, coupled with conservative inheritance, it resulted in massive losses of TMK. The folk doctors have accumulated their factions based on self-study or ancestral experience. There was different treatment experience among folk doctors, but the safety and effectiveness should be paid attention to. The folk doctors used various herbal medicines, but there was a lack of standards or specifications for quality control. Given the problems existing in inheritance and development, conservation strategies were proposed in the present study.

Modified Abietane Diterpenoids from Whole Plants of Selaginella moellendorffii.

A new modified abietane diterpenoid, (3S,4S,5R,10S)-18(4→3)-abeo-3,4,12,18-tetrahydroxy-8,11,13-abietatrien-7-one (1), and two novel dimers, selaginedorffones A (2) and B (3), featuring a new cyclohexene moiety that was biogenetically constructed from two modified abietane diterpenoids through a Diels-Alder reaction were obtained from a methanolic extract of Selaginella moellendorffii, a traditional Chinese herb. The structures of 1-3 were identified by a combination of NMR spectroscopic analysis and ECD calculations. In the present study, diterpenoids were identified from S. moellendorffii for the first time, which supports the presence of diterpene synthases in this plant. These three diterpenoids (1-3) were evaluated for their growth-inhibitory activities against several human cancer cell lines. Of these substances, selaginedorffone B (3) showed cytotoxicity against the MCF-7 human-breast-cancer-cell line (IC50 9.0 µM).

New aporphine alkaloids from the aerial parts of Piper semiimmersum §.

Two new aporphine alkaloids, semiimmersumines A (1) and B (2), along with 20 known compounds, were isolated from the aerial parts of Piper semiimmersum (Piperaceae). The structures of the new compounds were elucidated based on the analysis of 1D and 2D NMR, MS, and CD data. The absolute configuration of semiimmersumine A (1) was determined by single crystal X-ray diffraction analysis using anomalous dispersion with copper radiation. The effects of all compounds from the plant on rabbit platelet aggregation induced by thrombin (IIa) or PAF were also evaluated.

[Chemical constituents of Hypericum stellatum and their antioxidant bioactivities].

Hypericum stellatum is an important ethnomedicinal plant endemic to southwest China. Ultra high performance liquid chromatography with quadrupole time-of-flight mass spectrometry (UPLC-Q-TOF-MS) was applied to analyze the chemical constituents of H. stellatum. Seventeen compounds from H. stellatum were tentatively identified using UPLC-Q-TOF-MS data. Antioxidant activity and total phenolic content were investigated by DPPH assay and Folin-Ciocalted methods. The EtOAc extract with high total phenolic content showed prominent antioxidant activity. The EtOAc extract of H. stellatum was separated and purified by column chromatography, including silica gel, Sephedex LH-20, and RP-HPLC. The isolates were defined by 1D, 2D NMR data. As a result, ten compounds were isolated and assigned as quercetin (Ⅰ), quercetin 3-O-ß-D-glucopyranoside (Ⅱ), 1,3,6,7-tetrahydroxylxanthone (Ⅲ), 1,3,5,6-tetrahydroxyxanthone (Ⅳ), 1,3,7-trihydroxyxanthone (Ⅴ), 3, 6, 7-trihydroxy-1-methoxyxanthone (Ⅵ), calycinoxanthon D (Ⅶ), caffeic acid ethyl ester (Ⅷ), chlorogenic acid (Ⅸ) and chlorogenic acid ethyl ester (Ⅹ). This is the first report on chemical constituents and bioactivity of H. stellatum. The antioxidant activity of chemical constituents was tentatively found, which provided a foundation for further researches on the genus Hypericum and the traditional uses of H. stellatum.

[Studies on volatile oils compounds of Acorus macrospadiceus based on GC-MS, an ethnomedicinal and food plant used by local people in southwest China].

Acorus macrospadiceus is a common medicinal and food plant used different ethnic groups in Guizhou and surrounding areas. In this paper, the leaf and rhizome tissues of A. macrospadiceus were hydro-distilled to extract the volatile oils. The chemical constituents of these oils were analyzed by GC-MS and identified using the NIST 14.0 & NIST 14.0s mass spectral libraries. The relative contents of chemical constituents from the different plant parts were determined by area normalization. The analysis of A. macrospadiceus volatile oils resulted in the identification of 25 compounds from the leaf and 36 compounds from the rhizome. The identified compounds accounted for 97.85% of the leaf essential oil content and 97.18% of the rhizome essential oil content. The main volatile constituent of A. macrospadiceus was identified as estragole (93.56% of total oil content in leaf and 71.62% of total oil content in rhizome). Fourteen compounds were found to be common to essential oils of both leaf and rhizome. However, the relative amounts of these compounds were significantly different between the plant parts; the remaining identified compounds were unique to each part. This comparison of volatile oils from the different parts of A. macrospadiceus can serve as a reference for future development. Because of the higher estragole content and better harvesting sustainability of the leaves compared to rhizomes, the leaves of A. macrospadiceus deserve consideration for sustainable development. However, when we use it as a medical plant, we should draw a distinction between it with A. tatarinowii.

Multidrug resistance-selective antiproliferative activity of Piper amide alkaloids and synthetic analogues.

Twenty-five amide alkaloids (1-25) from Piper boehmeriifolium and 10 synthetic amide alkaloid derivatives (39-48) were evaluated for antiproliferative activity against eight human tumor cell lines, including chemosensitive and multidrug-resistant (MDR) cell lines. The results suggested tumor type-selectivity. 1-[7-(3,4,5-Trimethoxyphenyl)heptanoyl]piperidine (46) exhibited the best inhibitory activity (IC50=4.94 µM) against the P-glycoprotein (P-gp)-overexpressing KBvin MDR sub-line, while it and all other tested compounds, except 9, were inactive (IC50 >40 µM) against MDA-MB-231 and SK-BR-3. Structure-activity relationships (SARs) indicated that (i) 3,4,5-trimethoxy phenyl substitution is critical for selectivity against KBvin, (ii) the 4-methoxy group in this pattern is crucial for antiproliferative activity, (iii) double bonds in the side chain are not needed for activity, and (iv), in arylalkenylacyl amide alkaloids, replacement of an isobutylamino group with pyrrolidin-1-yl or piperidin-1-yl significantly improved activity. Further study on Piper amides is warranted, particularly whether side chain length affects the ability to overcome the MDR cancer phenotype.

Indole alkaloid glycosides from the aerial parts of Strobilanthes cusia.

Three indole alkaloid glycosides, strobilanthosides A-C (1-3), two known indole alkaloid glucosides (4 and 5), and five phenylethanoid glycosides (8-10) were isolated from the aerial parts of Strobilanthes cusia. The structures of the new compounds were elucidated by spectrometric analysis, and the absolute configurations of 1 and 2 were established by ECD spectrocsopy. N'-ß-d-Glucopyranosylindirubin (5) showed weak antibacterial activity (MIC 62.5-125 µM) against Staphylococcus aureus.

Nudibaccatumone, a trimer comprising a phenylpropanoid and two sesquiterpene moieties from Piper nudibaccatum.

A new complex natural product with a C39 skeleton, named nudibaccatumone, and the known sesquiterpenes (+)-spathulenol, (-)-4ß,10α-aromadendranediol, and ent-T-muurolol, as well as the phenylpropanoid hydroxychavicol, were isolated from the aerial parts of Piper nudibaccatum. The structure and absolute configuration of nudibaccatumone were elucidated using spectroscopic methods and ECD calculations. A 1,8-Michael addition reaction and an intermolecular, inverse electron demand Diels-Alder reaction are proposed as the key steps in the biosynthesis of nudibaccatumone.

New monoterpene lactones from Actaea cimicifuga.

Three new monoterpene lactones, cimicifugolides A-C (1-3), along with a known one (4), were identified from the dried rhizome of Actaea cimicifuga L. that was used as traditional Chinese medicine for thousands of years with the Chinese common name of shengma. The structures of the new isolates were established using spectroscopic methods, including NMR, mass, UV, and IR spectra. The inhibition activity of compounds 1, 2, and 4 against pancreatic lipase was evaluated.

Sarmentosumols A to F, new mono- and dimeric alkenylphenols from Piper sarmentosum.

Two new mono- and four new dimeric alkenylphenols, namely sarmentosumols A to F (1-6), were isolated from the aerial parts of Piper sarmentosum. The structures of these compounds were determined through a detailed analysis of NMR and MS data. Their antimicrobial activity against Escherichia coli, Staphyloccocus aureus, and Candida albicans, and their cytotoxic activity against human myeloid leukemia (K562) and human lung adenocarcinoma (A549) cell lines were also evaluated. Except for sarmentosumol A (1), whose MIC on S. aureus was reported to be 7.0 µg/mL, none of the other newly discovered compounds exhibited antimicrobial property. The studied compounds did not possess any cytotoxic property.

Diversification and genetic differentiation of cultivated melon inferred from sequence polymorphism in the chloroplast genome.

Molecular analysis encouraged discovery of genetic diversity and relationships of cultivated melon (Cucumis melo L.). We sequenced nine inter- and intra-genic regions of the chloroplast genome, about 5500 bp, using 60 melon accessions and six reference accessions of wild species of Cucumis to show intra-specific variation of the chloroplast genome. Sequence polymorphisms were detected among melon accessions and other Cucumis species, indicating intra-specific diversification of the chloroplast genome. Melon accessions were classified into three subclusters by cytoplasm type and then into 12 subgroups. Geographical origin and seed size also differed between the three subclusters. Subcluster Ia contained small-seed melon from Southern Africa and South and East Asia and subcluster Ib mainly consisted of large-seed melon from northern Africa, Europe and USA. Melon accessions of subcluster Ic were only found in West, Central and Southern Africa. Our results indicated that European melon groups and Asian melon groups diversified independently and shared the same maternal lineage with northern African large-seed melon and Southern African small-seed melon, respectively. Cultivated melon of subcluster Ic may have been domesticated independently in Africa. The presence of 11 cytoplasm types in Africa strongly supported African origin of cultivated melon and indicated the importance of germplasm from Africa.

Chemical constituents of Arisaema franchetianum tubers.

A novel pyrrolidine alkaloid, (2R*,3S*,5S*)-N,2-dimethyl-3-hydroxy-5-(10-phenyldecyl)pyrrolidine (1), and 17 known compounds were isolated from Arisaema franchetianum Engl. (Araceae) tubers. The 17 compounds were bergenin (2), emodin (3), caffeic acid (4), nobiletin (5), 3-O-ß-d-galactopyranosyl-hederagenin 28-O-ß-d-xylopyranosyl(1 â†’ 6)-ß-d-galactopyranosyl ester (6), coniferin (7), qingyangshengenin (8), methylconiferin (9), syringaresinol 4'-O-ß-d-glucopyranoside (10), gagaminine (11), perlolyrine (12), (S)-1-(1'-hydroxyethyl)-ß-carboline (13), 1-(ß-carboline-1-yl)-3,4,5-trihydroxy-1-pentanone (14), 1-methoxycarbonyl-ß-carboline (15), indolo[2,3-α]carbazole (16), 4-hydroxycinnamic acid methyl ester (17), and methyl 4-[2-hydroxy-2-(4-hydroxy-3-methoxyphenyl)-1-(hydroxymethyl)ethyl] ferulate (18). The inhibitory activities of compound 1 and its N-methyl derivative (1a) against porcine respiratory and reproductive syndrome virus (PRRSV), human leukemic K562 cells, and human breast cancer MCF-7 cells were evaluated. Compounds 1 [50% inhibited concentration (IC(50)) = 12.5 ± 0.6 µM] and 1a (IC(50) = 15.7 ± 0.9 µM) were cytotoxic against K562 cells. Compound 1a also had a weak effect on PRRSV with an IC(50) value of 31.9 ± 6.0 µM [selectivity index (SI) = 18.7].

Bioactive isoquinoline alkaloids from Corydalis saxicola.

Twelve isoquinoline alkaloids including two new nitro-containing tetrahydroprotoberberines, (-)-2,9-dihydroxyl-3,11-dimethoxy-1,10-dinitrotetrahydroprotoberberine (1) and (+)-4-nitroisoapocavidine (2), were isolated from the whole plant of Corydalis saxicola Bunting. The structures of the new compounds were established by spectroscopic analysis and chemical evidence. The inhibitory activity of these isolates against cholinesterase and canine parvovirus were evaluated. Compounds 1 and 1A, (+)-1-nitroapocavidine (5), berberine (8), palmatine (9), dehydrocavidine (10), and sanguinarine (11) showed potent inhibitory activity against acetylcholinesterase with IC(50) values of less than 10 µM, while only compound 1 possessed weak activity against canine parvovirus. Structure-activity studies demonstrated that the nitro substituents at ring A in the tetrahydroprotoberberines led to an increase in the anti-acetylcholinesterase activity.

Fire-prone Rhamnaceae with South African affinities in Cretaceous Myanmar amber.

The rapid Cretaceous diversification of flowering plants remains Darwin's 'abominable mystery' despite numerous fossil flowers discovered in recent years. Wildfires were frequent in the Cretaceous and many such early flower fossils are represented by charcoalified fragments, lacking complete delicate structures and surface textures, making their similarity to living forms difficult to discern. Furthermore, scarcity of information about the ecology of early angiosperms makes it difficult to test hypotheses about the drivers of their diversification, including the role of fire in shaping flowering plant evolution. We report the discovery of two exquisitely preserved fossil flower species, one identical to the inflorescences of the extant crown-eudicot genus Phylica and the other recovered as a sister group to Phylica, both preserved as inclusions together with burned plant remains in Cretaceous amber from northern Myanmar (~99 million years ago). These specialized flower species, named Phylica piloburmensis sp. nov. and Eophylica priscastellata gen. et sp. nov., exhibit traits identical to those of modern taxa in fire-prone ecosystems such as the fynbos of South Africa, and provide evidence of fire adaptation in angiosperms.

Cytotoxic amide alkaloids from Piper boehmeriaefolium.

Eight new amide alkaloids (1-8) and 19 known ones were isolated from the whole plant of Piper boehmeriaefolium. Their structures were determined through spectroscopic data analyses. Cytotoxic activity of these amides against human cervical carcinoma HeLa cells was evaluated, and 1-[(9E)-10-(3,4-methylenedioxyphenyl)-9-decenoyl]pyrrolidine (9) exhibited significant inhibitory activity with an IC(50) value of 2.7 µg/mL.

Molecular authentication of the ethnomedicinal plant Sabia parviflora and its adulterants by DNA barcoding technique.

Sabia parviflora Wall. ex Roxb. is a traditional herb widely used by Chinese people, especially by the Buyi ethnic group which resides in Guizhou and Yunnan provinces. According to the Chinese Ethnic Pharmacopeia, the species is commonly used for soothing the liver and for the treatment of icteric hepatitis, hemostasis, and inflammation. However, due to the similar morphological characters of Sabia species and higher market demands, there are many substitutes and adulterants of S. parviflora. In this study, the differential identification of 6 Sabia species and 7 adulterants were investigated through DNA sequence analysis of three candidate DNA barcodes (trnH-psbA, rbcL-α, matK). Based on sequence alignments, we concluded that not only the trnH-psbA spacer sequence can distinguish S. parviflora from other Sabia species, but the matK + rbcL-α sequences also can differentiate it from the substitutes and adulterants. The classification tree of all samples based on rbcL-α sequences indicated that the rbcL region can identify samples into a family/genus level. Our results suggest that the three candidate barcodes can be used for the identification of S. parviflora and to distinguish it from common substitutes or adulterants.

Two new compounds from Comastoma pedunlulatum.

Two new compounds, a xanthonoid and a flavonoid C-glycoside, were isolated from the ethyl acetate extract of the dried herb of Comastoma pedunlulatum. The structures of the new compounds were elucidated, respectively, as 1,8-dihydroxy-3,5-dimethoxyxanthone 1-O-[2-(4'-hydroxy-3',5'-dimethoxy-E-cinnamoyl)]-ß-D-xylopyranosyl-(1-6)-ß-D-glucopyranoside (1) and 6″-O-acetylisoorientin (2) on the basis of their spectroscopic and physicochemical properties.

Utricularia lihengiae (Lentibulariaceae), a new species from Northwest Yunnan, China.

Utricularia lihengiae, a new species from the Dulongjiang region of northwest Yunnan, China, is here described and illustrated. The new species belongs to the section Oligocista and is similar to U. bifida L. and U. scandens Benj., from which it can be easily distinguished by the dark purple stripe on the corolla. The new species also differs in its shorter inflorescence and the shape of the calyx lobes.

Genetic Diversity Evaluation and Conservation of Kam Fragrant Glutinous Rice (Oryza sativa L.) Germplasm in Southeast Guizhou, China.

The genetic diversity of rice germplasm is the basis for increases in rice yield and quality. The collection, assessment, and protection of the genetic diversity of rice germplasm is important for achieving sustainable agriculture and assuring food security. Many underdeveloped indigenous areas have abundant and valuable rice germplasm resources. However, in-depth assessments of the genetic diversity of rice germplasm from these areas and studies related to protecting these traditional cultures are not available. In this study, from 2005 to 2016, the authors have conducted in-depth evaluation of the genetic diversity of Kam fragrant glutinous rice germplasm resources in southeast Guizhou by using multidisciplinary comprehensive methods such as ethnobotany, cultural anthropology, and modern molecular markers. In total, 376 Kam fragrant glutinous rice samples from 42 villages in the Dong community in southeast Guizhou were collected. Agronomic traits of panicles were complex and exhibited diversity. Some varieties had good disease resistance and adaptation to cold and wet climates. The Dong people named the Kam fragrant glutinous rice varieties by using seven elements, including diverse traits, growth environment, and origin. Traditional folk classification, in addition to morphology and biological analysis using molecular markers, indicates that Kam fragrant glutinous rice includes 91 varieties. Kam fragrant glutinous rice comprises a very high number of varieties, most of which are japonica-type and exhibit a high level of genetic diversity. The traditional folk classification of Kam fragrant glutinous rice by the Dong community is consistent with the biological classification. The traditional naming of Kam fragrant glutinous rice provides an important reference for understanding its genetic diversity. The high level of genetic diversity in Kam fragrant glutinous rice is not only related to the natural environment of the area but also tightly linked with the abundant and diverse Dong ethnic traditional cultures, which has led to protection of Kam fragrant glutinous rice's genetic diversity.