The ethnopharmacology, phytochemistry, pharmacology and toxicology of the genus Erycibe (Convolvulaceae).

ETHNOPHARMACOLOGICAL RELEVANCE: The genus Erycibe belongs to the Convolvulaceae family that contains approximately 70 species mainly distributed from tropical and subtropical Asia to north of Australia. Several Erycibe species are traditionally used in folk medicine for the treatment of various ailments, including rheumatic arthralgia, primary glaucoma, hepatopathies, and infectious and malignant diseases. AIM OF THE REVIEW: This review aims to summarize comprehensive and updated information on traditional medicinal uses, phytochemistry, pharmacology, and toxicology of Erycibe species to provide a reference for the further research and application of the Erycibe genus. MATERIALS AND METHODS: The scientific and extensive literatures between 1975 and 2020 were systematically gathered from scientific databases such as SciFinder Scholar, Science Direct, Web of Science, PubMed, Google Scholar, Scopus, Springer Link and China National Knowledge Infrastructure (CNKI), as well as Chinese herbal classic books, PhD and MSc theses, and several official websites. RESULTS: Erycibe species have been used for the treatment of various rheumatoid diseases, glaucoma, a variety of hepatic diseases, infectious diseases and various malignancies in the traditional and local medicine. Since the 1970s, 153 compounds, including coumarins, quinic acid derivatives, flavonoids, alkaloids, lignans, and others have been isolated from five species of the Erycibe genus. Pharmacological studies have shown that these extracts and compounds from the Erycibe genus have extensive activities consistent with the traditional and local applications, such as anti-glaucoma, anti-arthritic, hepatoprotective and anti-cancer activities, as well as anti-inflammatory, anti-respiratory syncytial virus (RSV), and neuroprotective properties. CONCLUSIONS: Although there are extensive data on the genus Erycibe, certain specific gaps still exist. For herbal preparations containing Erycibe species, clinical toxicological investigation is required for the safety of these herbal preparation therapies, as well as further investigations on pharmacokinetics and bioavailability for guideline for clinical application. Furthermore, more detailed pharmacological, toxicological and clinical researches are needed to assess the alternatives to Erycibe species. Systematic and comprehensive pre-clinical studies are similarly required to estimate the possibility of extracts and compounds from the genus Erycibe with bioactivity developing into new drugs.

Microscopic investigations of palynological features of convolvulaceous species from arid zone of Pakistan.

The pollen morphology of some species of glamorous family Convolvulaceae from arid zones of Pakistan has been evaluated. The pollen grains were acetolyzed, measured, described qualitatively, and illustrated using Light microscopy and scanning electron microscopy (SEM). The examined species have differences in shape, size, polarity and exine ornamentation, confirming the eurypalynous character. The pollen types varies from psilate to echinate and colpi to tricolporate, tetracolporate and pantocolporate. Exine ornamentation was exposed as perforate, reticulate and echinate. Spine morphology and exine sculpture are vital for the distinction of species. Pollen fertility shows that selected plants species are well-known in the Arid Zone. A taxonomic key is prepared to use these variations in the identification of species. Statistical analysis by using the Software XLSTAT exhibited that some morphological features is the main characters in identification of the taxa. These studied taxa were separated from each other using cluster Analysis. Our results constructed on MVSP ver. 3.22 software analyses that show morphological explanation; thus, the results highlight the importance of pollen morphology in the identification and characterization of species of the family convolvulacae in arid zone.

Phylogenetic and chemotypic diversity of Periglandula species in eight new morning glory hosts (Convolvulaceae).

Periglandula ipomoeae and P. turbinae (Ascomycota, Clavicipitaceae) are recently described fungi that form symbiotic associations with the morning glories (Convolvulaceae) Ipomoea asarifolia and Turbina corymbosa, respectively. These Periglandula species are vertically transmitted and produce bioactive ergot alkaloids in seeds of infected plants and ephemeral mycelia on the adaxial surface of young leaves. Whether other morning glories that contain ergot alkaloids also are infected by Periglandula fungi is a central question. Here we report on a survey of eight species of Convolvulaceae (Argyreia nervosa, I. amnicola, I. argillicola, I. gracilis, I. hildebrandtii, I. leptophylla, I. muelleri, I. pes-caprae) for ergot alkaloids in seeds and associated clavicipitaceous fungi potentially responsible for their production. All host species contained ergot alkaloids in four distinct chemotypes with concentrations of 15.8-3223.0 µg/g. Each chemotype was a combination of four or five ergot alkaloids out of seven alkaloids detected across all hosts. In addition, each host species exhibited characteristic epiphytic mycelia on adaxial surfaces of young leaves with considerable interspecific differences in mycelial density. We sequenced three loci from fungi infecting each host: the nuclear rDNA internal transcribed spacer region (ITS), introns of the translation factor 1-α gene (tefA) and the dimethylallyl-tryptophan synthase gene (dmaW), which codes for the enzyme that catalyzes the first step in ergot alkaloid biosynthesis. Phylogenetic analyses confirmed that these fungi are in the family Clavicipitaceae and form a monophyletic group with the two described Periglandula species. This study is the first to report Periglandula spp. from Asian, Australian, African and North American species of Convolvulaceae, including host species with a shrub growth form and host species occurring outside of the tropics. This study demonstrates that ergot alkaloids in morning glories always co-occur with Periglandula spp. and that closely related Periglandula spp. produce alkaloid chemotypes more similar than more distantly related species.

Different fingerprinting strategies to differentiate Porana sinensis and plants of Erycibe by high-performance liquid chromatography with diode array detection, ultra high performance liquid chromatography with tandem quadrupole mass spectrometry, and chemometrics.

Plants of Erycibe are widely used in traditional Chinese medicine for the treatment of joint pain and rheumatoid arthritis. With the reduction of Erycibe resources in the wild, Porana sinensis has been widely used as a substitute. However, it is important to understand the chemical distinctions between the two kinds of plants and identify their individual chemical markers. In this study, multiwavelength chromatographic fingerprint and precursor ion fingerprint techniques were used in conjunction with chemometric tools to fingerprint and thus differentiate between plant samples. The similar results obtained from different fingerprints prove the reliability of the two fingerprints. Results obtained from principal component analysis and orthogonal projection to latent structures discriminant analysis identified similarities between the chemical components of P. sinensis and plants of Erycibe. However, concentrations of 4-caffeoylquinic acid, 3,5-dicaffeoylquinic acid, 3,4-dicaffeoylquinic acid, and 4,5-dicaffeoylquinic acid were higher in P. sinensis than in plants of Erycibe, suggesting that P. sinensis may be more effective in medical treatments of some diseases than Erycibe.

[Analysis and identification of Semen Glycines Nigrae and Semen Pharbitidis by infrared spectroscopy].

Semen Glycines Nigrae and Semen Pharbitidis containing a large amount of fats and proteins are commonly used in Chinese herbal medicine. Tri-step infrared spectroscopy was applied to fast analyze and identify the two samples. In the conventional infrared spectroscopy, the samples both have obvious characteristic absorption peaks at 1,745 cm(-1) assigned to the stretching mode of C==O in esters. Furthermore, the two kinds of herbs have the peaks at 1,656 and 1,547 cm(-1) assigned to the amide I and II bands of protein. Obviously, the infrared spectra of herbs demonstrate that protein and fat is the major component in two kinds of herbs, and the relative intensity of the peaks assigned to fat and protein indicate their relative content is different. And the result is consistent with the reported. In the second derivative spectra, Semen Pharbitidis has a peak at 1,712 cm(-1) assigned to the organic acid, however, Semen Glycines Nigrae has not this absorption peak. In addition, in the second derivative spectra, appeared more differences between the two samples in shape and intensity of the peaks. In two-dimensional correlation infrared spectra, the two samples were visually distinguished due to their significant differences in auto-peak position and intensity. In the region of 1,500-1,700 cm(-1), Semen Glycines Nigrae has two autopeaks and Semen Pharbitidis has three autopeaks. In the region of 2,800-3,000 cm(-1), the samples both have two autopeaks, but the position of the strongest autopeak is different. It was demonstrated that the Tri-step infrared spectroscopy were successfully applied to fast analyze and identify the two kinds of samples containing the same major component, and made sure the foundation for future researches.

Estaquia de Ipomoea cairica (L. ) Sweet / Stem cutting of Ipomoea cairica (L. ) Sweet

A Ipomoea cairica (L.) Sweet é uma trepadeira herbácea nativa, amplamente utilizada na medicina popular brasileira e inexistem informações sobre a propagação vegetativa. Em vista disso, objetivou-se avaliar a presença de folhas nas estacas, o substrato e a dose de reguladores vegetais mais adequados para a propagação por estaquia. Foram conduzidos dois experimentos, no primeiro, foram avaliados dois tipos de estacas (com e sem folhas) e quatro substratos (areia, casca de arroz carbonizada, latossolo vermelho distrófico + matéria orgânica - 1:1, latossolo vermelho distrófico + matéria orgânica + areia - 1:1:2), enquanto no segundo foram testadas cinco concentrações diferentes de AIB (0, 250, 500, 750 e 1000 mg L-1). Após 20 dias, obteve-se 86,2% de estacas enraizadas no substrato areia e, no segundo experimento, observou-se que o AIB não influenciou a porcentagem de enraizamento (94% em média). Conclui-se que a presença de folhas melhora a qualidade do enraizamento, que os substratos indicados para a propagação são areia e casca de arroz carbonizada devido ao maior enraizamento, fácil disponibilidade e baixo custo, e que a utilização de AIB na concentração 250 mg L-1 é a mais adequada para propagação por estaquia de I. cairica.

Ipomoea cairica (L.) Sweet is an herbaceous climbing plant widely used in Brazilian folk medicine and there is no information regarding its vegetative propagation. In view of this, the aim of this study was to evaluate the presence of leaves on stem cuttings and the most adequate substrate and level of plant growth regulators for propagation by stem cuttings of this morning glory. Two experiments were conducted, in the first, two types of stem cuttings (with and without leaves) and four substrates (sand; carbonized rice hull; Haplortox + organic matter - 1:1; Haplortox + organic matter + sand - 1:1:2) were evaluated, and in the second experiment five different concentrations of IBA (0, 250, 500, 750 and 1000 mg L-1) were tested. After 20 days, we obtained 86.2% of cuttings rooted in sand substrate and in the second experiment IBA did not affect the rooting percentage (94% on average). We can conclude that the presence of leaves improved the quality of rooting, the substrates indicated for propagation are sand and carbonized rice hull due to greater rooting, easy availability and low cost, and the use of IBA at 250 mg L-1 is more appropriate to propagation by stem cuttings of I. cairica.

Phylogenetic analyses of nucleotide sequences confirm a unique plant intercontinental disjunction between tropical Africa, the Caribbean, and the Hawaiian Islands.

Phylogenetic analyses of nucleotide sequences of the internal transcribed spacers and 5.8 regions of the nuclear ribosomal DNA and of the trnH-psbA spacer of the chloroplast genome confirm that the three taxa of the Jacquemontia ovalifolia (Choicy) Hallier f. complex (Convolvulaceae) form a monophyletic group. Levels of nucleotide divergence and morphological differentiation among these taxa support the view that each should be recognized as distinct species. These three species display unique intercontinental disjunction, with one species endemic to Hawaii (Jacquemontia sandwicensis A. Gray.), another restricted to eastern Mexico and the Antilles [Jacquemontia obcordata (Millspaugh) House], and the third confined to East and West Africa (J. ovalifolia). The Caribbean and Hawaiian species are sister taxa and are another example of a biogeographical link between the Caribbean Basin and Polynesia. We provide a brief conservation review of the three taxa based on our collective field work and investigations; it is apparent that J. obcordata is highly threatened and declining in the Caribbean.

Phylogeny of seed dormancy in Convolvulaceae, subfamily Convolvuloideae (Solanales).

BACKGROUND AND AIMS: The water gap is an important morphoanatomical structure in seeds with physical dormancy (PY). It is an environmental signal detector for dormancy break and the route of water into the non-dormant seed. The Convolvulaceae, which consists of subfamilies Convolvuloideae (11 tribes) and Humbertoideae (one tribe, monotypic Humberteae), is the only family in the asterid clade known to produce seeds with PY. The primary aim of this study was to compare the morphoanatomical characteristics of the water gap in seeds of species in the 11 tribes of the Convolvuloideae and to use this information, and that on seed dormancy and storage behaviour, to construct a phylogenetic tree of seed dormancy for the subfamily. METHODS: Scanning electron microscopy (SEM) was used to define morphological changes in the hilum area during dormancy break; hand and vibratome sections were taken to describe the anatomy of the water gap, hilum and seed coat; and dye tracking was used to identify the initial route of water entry into the non-dormant seed. Results were compared with a recent cladogram of the family. KEY RESULTS: Species in nine tribes have (a) layer(s) of palisade cells in the seed coat, a water gap and orthodox storage behaviour. Erycibe (Erycibeae) and Maripa (Maripeae) do not have a palisade layer in the seed coat or a water gap, and are recalcitrant. The hilar fissure is the water gap in relatively basal Cuscuteae, and bulges adjacent to the micropyle serve as the water gap in the Convolvuloideae, Dicranostyloideae (except Maripeae) and the Cardiochlamyeae clades. Seeds from the Convolvuloideae have morphologically prominent bulges demarcated by cell shape in the sclereid layer, whereas the Dicranostyloideae and Cardiochlamyeae have non-prominent bulges demarcated by the number of sub-cell layers. The anatomy and morphology of the hilar pad follow the same pattern. CONCLUSIONS: PY in the subfamily Convolvuloideae probably evolved in the aseasonal tropics from an ancestor with recalcitrant non-dormant seeds, and it may have arisen as Convolvulaceae radiated to occupy the seasonal tropics. Combinational dormancy may have developed in seeds of some Cuscuta spp. as this genus moved into temperate habitats.

Evolvulus alsinoides (Convolvulaceae): an American herb in the Old World.

People in the Indian region often apply shankhapushpi and vishnukranti, two Sanskrit-based common names, to Evolvulus alsinoides. These are pre-European names that are applied to a medicinal American species transported into the area. The period of introduction is uncertain, but probably took place in the 1500s or 1600s. Examination of relationships of Evolvulus alsinoides, geographic distribution, its names in Asia, medical uses, and chemical and laboratory analysis indicates that the alien plant was adopted, given an ancient Indian name, and incorporated into some Old World pharmacopoeias. The herb apparently was included in medicines because it not only reminded people of certain aspects of their gods and goddesses, but also because the chemicals it contained were useful against some maladies.

Systematics and plastid genome evolution of the cryptically photosynthetic parasitic plant genus Cuscuta (Convolvulaceae).

BACKGROUND: The genus Cuscuta L. (Convolvulaceae), commonly known as dodders, are epiphytic vines that invade the stems of their host with haustorial feeding structures at the points of contact. Although they lack expanded leaves, some species are noticeably chlorophyllous, especially as seedlings and in maturing fruits. Some species are reported as crop pests of worldwide distribution, whereas others are extremely rare and have local distributions and apparent niche specificity. A strong phylogenetic framework for this large genus is essential to understand the interesting ecological, morphological and molecular phenomena that occur within these parasites in an evolutionary context. RESULTS: Here we present a well-supported phylogeny of Cuscuta using sequences of the nuclear ribosomal internal transcribed spacer and plastid rps2, rbcL and matK from representatives across most of the taxonomic diversity of the genus. We use the phylogeny to interpret morphological and plastid genome evolution within the genus. At least three currently recognized taxonomic sections are not monophyletic and subgenus Cuscuta is unequivocally paraphyletic. Plastid genes are extremely variable with regards to evolutionary constraint, with rbcL exhibiting even higher levels of purifying selection in Cuscuta than photosynthetic relatives. Nuclear genome size is highly variable within Cuscuta, particularly within subgenus Grammica, and in some cases may indicate the existence of cryptic species in this large clade of morphologically similar species. CONCLUSION: Some morphological characters traditionally used to define major taxonomic splits within Cuscuta are homoplastic and are of limited use in defining true evolutionary groups. Chloroplast genome evolution seems to have evolved in a punctuated fashion, with episodes of loss involving suites of genes or tRNAs followed by stabilization of gene content in major clades. Nearly all species of Cuscuta retain some photosynthetic ability, most likely for nutrient apportionment to their seeds, while complete loss of photosynthesis and possible loss of the entire chloroplast genome is limited to a single small clade of outcrossing species found primarily in western South America.

Chemotaxonomy of the pantropical genus Merremia (Convolvulaceae) based on the distribution of tropane alkaloids.

The occurrence and distribution of tropane and biogenetically related pyrrolidine alkaloids in 18 Merremia species of paleo-, neo-, and pantropical occurrence have been studied. The extensive GC-MS study included members of almost all sections of the genus and has been carried out with epigeal vegetative parts as well as with roots. It comprises altogether 74 tropanes and 13 pyrrolidines including nicotine. Along with datumetine known already from a solanaceous species, the study led to the isolation (from M. dissecta and M. guerichii, respectively) and structure elucidation (spectral data) of four novel 3alpha-acyloxytropanes, merresectines A-D: 3alpha-(4-methoxybenzoyloxy)nortropane (A), 3alpha-kurameroyloxytropane (B), 3alpha-nervogenoyloxytropane (C), 3alpha-[4-(beta-D-glucopyranosyloxy)-3-methoxy-5-(3-methyl-2-butenyl)benzoyloxy]tropane (beta-d-glucoside of D). Moreover, the novel 3alpha,6beta-di-(4-methoxybenzoyloxy)tropane (merredissine) has been isolated from M. dissecta and structurally elucidated. In addition the structures of datumetine and merresectine A could be confirmed by synthesis. Spectral data for two known 3alpha-acyloxytropanes (merresectine E beta-D-glucoside, 4'-dihydroconsabatine) and one known 3beta-acyloxytropane (concneorine) are documented for the first time. The structures of three further merresectines (F-H) have been determined by mass spectrometry. Furthermore, the linkage (2',3- and 2',4-, respectively) of two position isomer N-methylpyrrolidinylhygrines was proven by synthesis. The results of the study contribute to the solution of infrageneric taxonomic problems. Whereas all species yield pyrrolidine alkaloids without suitably differentiating results the diverging occurrence of tropane alkaloids leads to three groups of sections: (1) taxa free of tropanes, (2) taxa with simple tropanes, and (3) taxa with merresectines in addition to simple tropanes.

Calystegines as chemotaxonomic markers in the Convolvulaceae.

An extended GC-MS study of 129 convolvulaceous species belonging to 29 genera (all 12 tribes) including the results of a previous survey (65 spp.) revealed the occurrence of one to six polyhydroxy alkaloids of the nortropane type (calystegines) in 62 species belonging to 22 genera of all tribes except the unique parasitic Cuscuteae. The large genus Ipomoea turned out to comprise calystegine-positive species in at least eight out of ten sections checked. The number of the calystegines used as reference compounds has been increased from seven (previous survey) to 11 (present study). Furthermore, the results concerning these additional four alkaloids could also be completed for all species of the previous survey. The plant material (epigeal vegetative parts and/or roots, flowers, fruits/seeds) was obtained from collections in the wild from a wide range of tropical, subtropical, and temperate locations of all continents as well as from cultivation in the greenhouse. All plant organs turned out to be potential locations for the occurrence of these metabolites though they are detectable often only in certain organs of a given species. Three genera (Cuscuta, Operculina, Polymeria) might have lost the ability to synthesize these plesiomorphic characters in the course of the evolution since the examination of several different organs and/or provenances of five species each failed to show calystegines as constituents. Nevertheless, the present data clearly demonstrate that the occurrence of calystegines is an almost consistent trait in the Convolvulaceae in principle, from basal to most advanced tribes.