Enhanced wound healing potential of arabincoside B isolated from Caralluma Arabica in rat model; a possible dressing in veterinary practice.

BACKGROUND: Wound management is a critical procedure in veterinary practice. A wound is an injury that requires the body's cells' alignment to break down due to external assault, such as trauma, burns, accidents, and diseases. Re-epithelization, extracellular matrix deposition, especially collagen, inflammatory cell infiltration, and development of new blood capillaries are the four features that are used to evaluate the healing process. Using a natural extract for wound management is preferred to avoid the side effects of synthetic drugs. The current study aimed to assess the effect of major pregnane glycoside arabincoside B (AR-B) isolated from Caralluma arabica (C. arabica) for the wound healing process. METHOD: AR-B was loaded on a gel for wound application. Rats were randomly distributed into six groups: normal, positive control (PC), MEBO®, AR-B 0.5%, AR-B 1%, and AR-B 1.5%, to be 6 animals in each group. Wounds were initiated under anesthesia with a 1 cm diameter tissue needle, and treatments were applied daily for 14 days. The collected samples were tested for SOD, NO, and MDA. Gene expression of VEGF and Caspase-3. Histopathological evaluation was performed at two-time intervals (7 and 14 days), and immunohistochemistry was done to evaluate α -SMA, TGF-ß, and TNF-α. RESULT: It was found that AR-B treatment enhanced the wound healing process. AR-B treated groups showed reduced MDA and NO in tissue, and SOD activity was increased. Re-epithelization and extracellular matrix deposition were significantly improved, which was confirmed by the increase in TGF-ß and α -SMA as well as increased collagen deposition. TNF-α was reduced, which indicated the subsiding of inflammation. VEGF and Caspase-3 expression were reduced. CONCLUSION: Our findings confirmed the efficiency of AR-B in enhancing the process of wound healing and its potential use as a topical wound dressing in veterinary practice.

The Composition and Biochemical Properties of Strophantus (Apocynaceae), with a Focus on S. sarmentosus.

The genus Strophantus belongs to the Apocynaceae family of flowering plants which grows primarily in tropical Africa. The plants are widely used in traditional herbal medicine. S. sarmentosus, in particular, is used for the treatment of, e.g., joint pain and rheumatoid arthritis, wound infections, head lice, diarrhea, snake bite, and eye conditions. Despite its widespread use, dedicated research characterizing its bioactive plant components is scarce. Investigations have focused mainly on its cardenolides because of their cardioactivity and historical use as cardiotonic. There are also studies concerning the antibacterial, antioxidant, and anti-inflammatory activity of plant extracts. This review summarizes the present knowledge surrounding the biochemical and analytical research on Strophantus, in general, and S. sarmentosus, in particular, and describes the current state of the field based on the available scientific literature.

Antifungal Potential of Secondary Metabolites Derived from Arcangelisia flava (L.) Merr.: An Analysis of In Silico Enzymatic Inhibition and In Vitro Efficacy against Candida Species.

Considering the escalating resistance to conventional antifungal medications, it is critical to identify novel compounds that can efficiently counteract this challenge. The purpose of this research was to elucidate the fungicidal properties of secondary metabolites derived from Arcangelisia flava, with a specific focus on their efficacy against Candida species. This study utilized a combination approach comprising laboratory simulations and experiments to discern and evaluate the biologically active constituents present in the dichloromethane extract of A. flava. The in vitro experiments demonstrated that compounds 1 (palmatine) and 2 (fibraurin) exhibited antifungal properties. The compounds exhibited minimum inhibitory concentrations (MICs) ranging from 15.62 to 62.5 µg/mL against Candida sp. Moreover, compound 1 demonstrated a minimum fungicidal concentration (MFC) of 62.5 µg/mL against Candida glabrata and C. krusei. In contrast, compound 2 exhibited an MFC of 125 µg/mL against both Candida species. Based on a molecular docking study, it was shown that compounds 1 and 2 have a binding free energy of -6.6377 and -6.7075 kcal/mol, respectively, which indicates a strong affinity and specificity for fungal enzymatic targets. This study utilized pharmacophore modeling and Density Functional Theory (DFT) simulations to better understand the interaction dynamics and structural properties crucial for antifungal activity. The findings underscore the potential of secondary metabolites derived from A. flava to act as a foundation for creating novel and highly efficient antifungal treatments, specifically targeting fungal diseases resistant to existing treatment methods. Thus, the results regarding these compounds can provide references for the next stage in antifungal drug design. Further investigation is necessary to thoroughly evaluate these natural substances' clinical feasibility and safety characteristics, which show great potential as antifungal agents.

Style head in Apocynaceae: a very complex secretory activity performed by one tissue.

Nuptial glands are very diverse and associated with different pollination mechanisms. The greater the specificity in the pollen transfer mechanism from anther to stigma, the greater the morphological elaboration of flowers and functional complexity of the nuptial glands. In Apocynaceae, pollination mechanisms reached an extreme specificity, a fact that was only possible due to an extreme morphological synorganization and a profusion of floral glands. Although these glands are of different types, the vast majority have secretory cells only in the epidermis. In general, these epidermal cells produce many different compounds at the same time, and previous studies have demonstrated that in the style head, the functional complexity of epidermis has become even greater. Four types of style head are found in the family, which have different degrees of functional complexity in relation to the secretion produced and pollen dispersal mechanism. The secretion is fluid in types I, II and III, and the pollen is dispersed and adhered to the pollinator by the secretion produced by the style head. In type IV, the secretion hardens and acquires a specific shape, moulded by the spatial constraints of the adjacent floral organs. This evolutionary alteration is accompanied by changes in the structure and arrangement of the secretory cells, as well as in pollen aggregation and position of stigma. Histochemical analysis has shown that the secretion is mixed and highly complex, especially in the style head type IV, where the secretion, called translator, is formed by a rigid central portion, which adheres to the pollinator, and two caudicles that attach to two pollinia. The translator has a distinct composition in its different parts. Further studies are needed to answer the new questions that have arisen from the discovery of this highly functional complexity of the secretory tissue.

Exposure of Caralluma tuberculata to biogenic selenium nanoparticles as in vitro rooting agent: Stimulates morpho-physiological and antioxidant defense system.

The commercial-scale production of Caralluma tuberculata faces significant challenges due to lower seed viability and sluggish rate of root growth in natural conditions. To overcome these obstacles, using phyto-mediated selenium nanomaterials as an in vitro rooting agent in plant in vitro cultures is a promising approach to facilitate rapid propagation and enhance the production of valuable therapeutic compounds. This study aimed to investigate the impact of phytosynthesized selenium nanoparticles (SeNPs) on the morphological growth attributes, physiological status, and secondary metabolite fabrication in in vitro propagated Caralluma tuberculata. The results demonstrated that a lower dose of SeNPs (100 µg/L) along with plant growth regulators (IBA 1 mg/L) had an affirmative effect on growth parameters and promoted earliest root initiation (4.6±0.98 days), highest rooting frequency (68.21±5.12%), number of roots (6.3±1.8), maximum fresh weight (710±6.01 mg) and dry weight (549.89±6.77 mg). However, higher levels of SeNPs (200 and 400 µg/L) in the growth media proved detrimental to growth and development. Further, stress caused by SeNPs at 100 µg/L along with PGRs (IBA 1 mg/L) produced a higher level of total chlorophyll contents (32.66± 4.36 µg/ml), while cultures exposed to 200 µg/L SeNPs alone exhibited the maximum amount of proline contents (10.5± 1.32 µg/ml). Interestingly, exposure to 400 µg/L SeNPs induced a stress response in the cultures, leading to increased levels of total phenolic content (3.4 ± 0.052), total flavonoid content (1.8 ± 0.034), and antioxidant activity 82 ± 4.8%). Furthermore, the combination of 100 µg/L SeNPs and plant growth regulators (1 mg/L IBA) led to accelerated enzymatic antioxidant activities, including superoxide dismutase (SOD = 4.4 ± 0.067 U/mg), peroxidase dismutase (POD = 3.3 ± 0.043 U/mg), catalase (CAT = 2.8 ± 0.048 U/mg), and ascorbate peroxidase (APx = 1.6 ± 0.082 U/mg). This is the first report that highlights the efficacy of SeNPs in culture media and presents a promising approach for the commercial propagation of C. tuberculata with a strong antioxidant defense system in vitro.

[Two new benzyl-benzoate glucosides from Plumeria rubra].

The components with hypoglycemic activity in Plumeria rubra were isolated and purified by various column chromatography techniques and activity tracing methods. The physical and chemical properties of all the purified monomer compounds were characterized and analyzed, and a total of six compounds were isolated and identified, including 6″-acetyl-6-hydroxy-benzyl-benzoate-2-O-ß-D-glucoside(1), 6-acetyl-6-hydroxy-benzyl-benzoate-2-O-ß-D-glucoside-(1→6″)-ß-D-glucoside(2), 2-hydroxy-6-methoxy-benzyl-benzoate-2-O-ß-D-glucoside(3), 6-hydroxy-benzyl-benzoate-2-O-ß-D-glucoside(4), 6-hydroxy-benzyl-benzoate-2-O-ß-D-glucoside-(1→6″)-ß-D-glucoside(5), and 6-hydroxy-benzyl-benzoate-2-O-ß-D-glucoside-(1→6″)-ß-D-xyloside(6). Compounds 1 and 2 were new compounds, and compounds 3-6 were isolated from Plumeria for the first time. The α-glucosidase inhibitory activity of six identified compounds was tested. The results show that compounds 1-6 show certain inhibitory activity with an IC_(50) value ranging from 8.2 to 33.5 µmol·L~(-1).

A remarkable new deep-sea nereidid (Annelida: Nereididae) with gills.

Nereidid polychaetes are well known from shallow marine habitats, but their diversity in the deep sea is poorly known. Here we describe an unusual new nereidid species found at methane seeps off the Pacific coast of Costa Rica. Specimens of Pectinereis strickrotti gen. nov., sp. nov. had been observed dating back to 2009 swimming just above the seafloor at ~1,000 m depth but were not successfully captured until 2018. Male epitokes were collected as well as a fragment of an infaunal female found in a pushcore sample. The specimens were all confirmed as the same species based on mitochondrial COI. Phylogenetic analyses, including one based on available whole mitochondrial genomes for nereidids, revealed no close relative, allowing for the placement of the new species in its own genus within the subfamily Nereidinae. This was supported by the unusual non-reproductive and epitokous morphology, including parapodial cirrostyles as pectinate gills, hooked aciculae, elfin-shoe-shaped ventral cirrophores, and elongate, fusiform dorsal ligules emerging sub-medially to enlarged cirrophores. Additionally, the gill-bearing subfamily Dendronereidinae, generally regarded as a junior synonym of Gymnonereidinae, is reviewed and it is here reinstated and as a monogeneric taxon.

In Silico and In Vitro Screening of Some Pregnane Glycosides Isolated from Certain Caralluma Species as SARS-COV-2 Main Protease Inhibitors.

SARS-CoV-2 caused pandemic represented a major risk for the worldwide human health, animal health and economy, forcing extraordinary efforts to discover drugs for its prevention and cure. Considering the extensive interest in the pregnane glycosides because of their diverse structures and excellent biological activities, we investigated them as antiviral agents against SARS-COV-2. We selected 21 pregnane glycosides previously isolated from the genus Caralluma from Asclepiadaceae family to be tested through virtual screening molecular docking simulations for their potential inhibition of SARS-CoV-2 Mpro. Almost all target compounds showed a more or equally negative docking energy score relative to the co-crystallized inhibitor X77 (S=-12.53 kcal/mol) with docking score range of (-12.55 to -19.76 kcal/mol) and so with a potent predicted binding affinity to the target enzyme. The activity of the most promising candidates was validated by in vitro testing. Arabincoside C showed the highest activity (IC50=35.42 µg/ml) and the highest selectivity index (SI=9.9) followed by Russelioside B (IC50=50.80 µg/ml), and Arabincoside B (IC50=53.31 µg/ml).

Review of Herbal Medicinal Plants Used in the Management of Cancers in the East Africa Region from 2019 to 2023.

BACKGROUND: In the East African region, herbal plants are essential in the treatment and control of cancer. Given the diverse ecological and cultural makeup of the regional states, it is likely that different ethnic groups will use the same or different plants for the same or different diseases. However, since 2019, this has not been compiled into a single study. PURPOSE: The study aimed to compile and record the medicinal plants utilized in East Africa from April 2019 to June 2023 to treat various cancer types. MATERIALS AND METHODS: The study examined 13 original studies that included ethnobotanical research conducted in East Africa. They were retrieved from several internet databases, including Google Scholar, Scopus, PubMed/Medline, Science Direct, and Research for Life. The study retrieved databases on plant families and species, plant parts used, preparation methods and routes of administration, and the country where the ethnobotanical field surveys were conducted. Graphs were produced using the GraphPad Prism 8.125 program (GraphPad Software, Inc., San Diego, CA). Tables and figures were used to present the data, which had been condensed into percentages and frequencies. RESULTS: A total of 105 different plant species from 45 different plant families were identified, including Asteraceae (14), Euphorbiaceae (12), Musaceae (8), and Apocynaceae (7). Uganda registered the highest proportion (46% of the medicinal plants used). The most commonly mentioned medicinal plant species in cancer management was Prunus africana. Herbs (32%), trees and shrubs (28%), and leaves (45%) constituted the majority of herbal remedies. Most herbal remedies were prepared by boiling (decoction) and taken orally (57%). CONCLUSION: East Africa is home to a wide variety of medicinal plant species that local populations and herbalists, or TMP, frequently use in the treatment of various types of cancer. The most frequently used families are Asteraceae and Euphorbiaceae, with the majority of species being found in Uganda. The most frequently utilized plant species is Prunus africana. Studies on the effectiveness of Prunus africana against other malignancies besides prostate cancer are required.

ß-keto amyrin isolated from Cryptostegia grandiflora R. br. inhibits inflammation caused by Daboia russellii viper venom: Direct binding of ß-keto amyrin to phospholipase A2.

The search for mechanism-based anti-inflammatory therapies is of fundamental importance to avoid undesired off-target effects. Phospholipase A2 (PLA2) activity is a potential molecular target for anti-inflammatory drugs because it fuels arachidonic acid needed to synthesize inflammation mediators, such as prostaglandins. Herein, we aim to investigate the molecular mechanism by which ß-keto amyrin isolated from a methanolic extract of Cryptostegia grandiflora R. Br. Leaves can inhibit inflammation caused by Daboia russellii viper (DR) venom that mainly contains PLA2. We found that ß-keto amyrin neutralizes DR venom-induced paw-edema in a mouse model. Molecular docking of PLA2 with ß-keto amyrin complex resulted in a higher binding energy score of -8.86 kcal/mol and an inhibition constant of 611.7 nM. Diclofenac had a binding energy of -7.04 kcal/mol and an IC50 value of 620 nM, which predicts a poorer binding interaction than ß-keto amyrin. The higher conformational stability of ß-keto amyrin interaction compared to diclofenac is confirmed by molecular dynamics simulation. ß-keto amyrin isolated from C. grandiflora inhibits the PLA2 activity contained in Daboia russellii viper venom. The anti-inflammatory property of ß-keto amyrin is due to its direct binding into the active site of PLA2, thus inhibiting its enzyme activity.

Chemodiverse monoterpene indole alkaloids from Kopsia teoi, inhibitory potential against α-amylase, and their molecular docking studies.

Diabetes mellitus stands as a metabolic ailment marked by heightened blood glucose levels due to inadequate insulin secretion. The primary aims of this investigative inquiry encompassed the isolation of phytochemical components from the bark of Kopsia teoi, followed by the assessment of their α-amylase inhibition. The phytochemical composition of the K. teoi culminated in the discovery of a pair of new indole alkaloids; which are 16-epi-deacetylakuammiline N(4)-methylene chloride (akuammiline) (1), and N(1)-methoxycarbonyl-11-methoxy-12-hydroxy-Δ14-17-kopsinine (aspidofractinine) (2), together with five known compounds i.e. kopsiloscine G (aspidofractinine) (3), akuammidine (sarpagine) (4), leuconolam (aspidosperma) (5), N-methoxycarbonyl-12-methoxy-Δ16, 17-kopsinine (aspidofractinine) (6), and kopsininate (aspidofractinine) (7). All compounds were determined via spectroscopic analyses. The in vitro evaluation against α-amylase showed good inhibitory activities for compounds 5-7 with the inhibitory concentration (IC50) values of 21.7 ± 1.2, 34.1 ± 0.1, and 30.0 ± 0.8 µM, respectively compared with the reference acarbose (IC50 = 34.4 ± 0.1 µM). The molecular docking outputs underscored the binding interactions of compounds 5-7 ranging from -8.1 to -8.8 kcal/mol with the binding sites of α-amylase. Consequently, the outcomes highlighted the anti-hyperglycemic attributes of isolates from K. teoi.

Bioactive 5/5/5/6 Four-Ring System Iridoids from Plumeria alba L.

Two rare 5/5/5/6 four-ring system iridoids, allamancins A and B (1 and 2) together with one known biogenetically related iridoid derivative, 3-O-methyallamancin (3) were isolated from the flowers of Plumeria alba L. The structures of these iridoid derivatives were determined by comprehensive spectroscopic analyses. The absolute configuration of 1 was confirmed by X-ray crystallographic analysis. The inhibitory activities of compounds 1-3 against nitric oxide (NO) production induced and three cancer cell lines were evaluated in vitro. Compounds 1 and 3 showed inhibitory activities on NO production with IC50 values of 18.3±0.12 and 22.1±0.14 µM, respectively. Compounds 1-3 showed moderate inhibitory activities against cancer cell lines of A549, Hela and MCF-7.

Caralluma pauciflorabased Ag-NPs activate ROS - induced apoptosis through down-regulation of AKT, mTOR and pI3K signaling in human gastric cancer (AGS) cells.

The phytochemicals found inCaralluma pauciflorawere studied for their ability to reduce silver nitrate in order to synthesise silver nanoparticles (AgNPs) and characterise their size and crystal structure. Thunbergol, 1,1,6-trimethyl-3-methylene-2-(3,6,9,13-tetram, Methyl nonadecanoate, Methyl cis-13,16-Docosadienate, and (1R,4aR,5S)-5-[(E)-5-Hydroxy-3-methylpent were the major compounds identified in the methanol extract by gas chromatography-mass spectrum analysis. UV/Vis spectra, Fourier-transform infrared spectroscopy, x-ray diffraction, scanning electron microscope with Energy Dispersive Xâray Analysis (EDAX), Dynamic Light Scattering (DLS) particle size analyser and atomic force microscope (AfM) were used to characterise theCaralluma paucifloraplant extract-based AgNPs. The crystal structure and estimated size of the AgNPs ranged from 20.2 to 43 nm, according to the characterization data. The anti-cancer activity of silver nanoparticles (AgNPs) synthesised fromCaralluma paucifloraextract. The AgNPs inhibited more than 60% of the AGS cell lines and had an IC50 value of 10.9640.318 g, according to the findings. The cells were further examined using fluorescence microscopy, which revealed that the AgNPs triggered apoptosis in the cells. Furthermore, the researchers looked at the levels of reactive oxygen species (ROS) in cells treated with AgNPs and discovered that the existence of ROS was indicated by green fluorescence. Finally, apoptotic gene mRNA expression analysis revealed that three target proteins (AKT, mTOR, and pI3K) were downregulated following AgNP therapy. Overall, the findings imply that AgNPs synthesised from Caralluma pauciflora extract could be used to treat human gastric cancer.

Quinoline, Indole, and Isogranatanine Alkaloids from Malayan Leuconotis eugeniifolia.

Nine new alkaloids, eugeniinalines A-H (1-8) and (+)-eburnamenine N-oxide (9), comprising one quinoline, six indole, and two isogranatanine alkaloids, were isolated from the stem-bark extract of the Malayan Leuconotis eugeniifolia. The structures and absolute configurations of these alkaloids were established based on the analysis of the spectroscopic data, GIAO NMR calculations, DP4+ probability analysis, TDDFT-ECD method, and X-ray diffraction analysis. Eugeniinaline A (1) represents a new pentacyclic quinoline alkaloid with a 6/6/5/6/7 ring system. Eugeniinaline G (7) and its seco-derivative, eugeniinaline H (8), were the first isogranatanine alkaloids isolated as natural products. The known alkaloids leucolusine (10) and melokhanine A (11) were found to be the same compound, based on comparison of the spectroscopic data of both compounds, with the absolute configuration of (7R, 20R, 21S). Eugeniinalines A and G (1 and 7) showed cytotoxic activity against the HT-29 cancer cell line with IC50 values of 7.1 and 7.2 µM, respectively.

Mitochondrial genome of Hancornia speciosa gomes: intergenic regions containing retrotransposons and predicted genes.

BACKGROUND: Plant mitochondrial genomes are characterized by high homologous recombination, extensive intergenic spacers, conservation in DNA sequences, and gene content. The Hancornia genus belongs to the Apocynaceae family, with H. speciosa Gomes being the sole species in the genus. It is an siganificant commercial fruit crop; however, only a number of studies have been conducted. In this study, we present the mitochondrial genome of H. speciosa and compare it with other mitochondrial genomes within the Apocynaceae family. METHODS AND RESULTS: A total of 2.8 Gb of Illumina paired-end reads were used to obtain the mitogenome, resulting in 22 contigs that were merged using 6.1 Gb of Illumina mate-pair reads to obtain a circular chromosome. The mitochondrial genome of H. speciosa is circular, containing 63 predicted functional genes, spanning a length of 741,811 bp, with a CG content of 44%. Within the mitogenome, 50 chloroplast DNA sequences, equivalent to 1.72% of the genome, were detected. However, intergenic spaces accounted for 703,139 bp (94.79% of the genome), and 287 genes were predicted, totaling 173,721 bp. CONCLUSION: This suggests the incorporation of nuclear DNA into the mitogenome of H. speciosa and self duplication. Comparative analysis among the mitogenomes in the Apocynaceae family revealed a diversity in the structure mediated by recombination, with similar gene content and large intergenic spaces.

Low-laser action analysis associated with Himatanthus drasticus extract in wound healing.

The aim of this study was to analyze the healing action of low-intensity laser therapy associated with Himatanthus drasticus in wound healing in mice. The study was experimental, analytical, controlled, randomized, and prospective. Twenty Wistar rats were divided into four groups: control with injury, injury + laser, wound + Himatanthus drasticus, and wound + laser + Himatanthus drasticus. The animals underwent surgical skin wounds on their backs, and different treatments were applied based on the group. The healing process was evaluated histologically through the analysis of collagen fibers, neovascularization, and inflammatory reaction. The results showed that low-intensity laser therapy and Himatanthus drasticus treatment improved the healing process in terms of collagen synthesis, decreased inflammatory cell migration, fibroblast proliferation, neovascularization, wound size reduction, and edema reduction. However, the combination of laser and Himatanthus drasticus did not show significant improvement compared to individual treatments. There were no statistical differences in polymorphonuclear cells between the treatment groups. Low-intensity laser therapy and Himatanthus drasticus have demonstrated positive properties in improving the healing process. Further research is needed to better understand their individual and combined effects. The study contributes to the exploration of alternative wound healing methods and encourages further investigation in this field.

Silver nanoparticles improve the fungicidal properties of Rhazya stricta decne aqueous extract against plant pathogens.

One of the most promising, non-toxic, and biocompatible developments for many biological activities is the green synthesis of nanoparticles from plants. In this work, we investigated the antifungal activity of silver nanoparticles (AgNPs) biosynthesized from Rhazya stricta aqueous extract against several plant pathogenic fungi. UV-visible spectroscopy, Zeta potential analysis, Fourier-transform infrared spectroscopy (FTIR), and transmitted electron microscopy (TEM) were used to analyze the biosynthesized AgNPs. Drechslera halodes, Drechslera tetramera, Macrophomina phaseolina, Alternaria alternata, and Curvularia australiensis were tested for their potential antifungal activity. Surface Plasmon Resonance (SPR) of Aq. AgNPs and Alkaline Aq. AgNPs was observed at 405 nm and 415 nm, respectively. FTIR analysis indicated hydroxyl, nitrile, amine, and ketone functional groups. Aq. AgNPs and Alka-line Aq. AgNPs had velocities of - 27.7 mV and - 37.9 mV and sizes of 21-90 nm and 7.2-25.3 nm, respectively, according to zeta potential studies and TEM. The antifungal examination revealed that all species' mycelial development was significantly inhibited, accompanied by severe ultra-structural alterations. Among all treatments, Aq. AgNPs were the most effective fungicide. M. phaseolina was statistically the most resistant, whereas A. alternata was the most vulnerable. To the best of our knowledge, this is the first report on R. stricta's antifungal activity against these species.

Specialized pollination by cecidomyiid flies and associated floral traits in Vincetoxicum sangyojarniae (Apocynaceae, Asclepiadoideae).

Specialized pollination systems frequently match a particular set of floral characteristics. Vincetoxicum spp. (Apocynaceae, Asclepiadoideae) have disk-shaped flowers with open access to rewards and reproductive organs. Flowers with these traits are usually associated with generalized pollination. However, the highly modified androecium and gynoecium that characterize asclepiads are thought to be associated with specialized pollinators. In V. sangyojarniae, we investigated floral biology, pollination, and the degree of pollinator specialization in two localities in Thailand. We examined floral traits that target legitimate pollinators. Flowers of V. sangyojarniae opened only at night, emitted floral scents containing mainly (E)-ß-ocimene, 1-octen-3-ol, (E)-4,8-dimethyl-1,3,7-nonatriene (E-DMNT) and N-(3-methylbutyl)acetamide, and provided sucrose-dominated nectar openly to insect visitors. Assessment of pollinator effectiveness indicated that V. sangyojarniae is functionally specialized for pollination by cecidomyiid flies. Although various insects, particularly cockroaches, frequently visited flowers, they did not carry pollinaria. Our results suggest that V. sangyojarniae attracts its fly pollinators by emitting floral volatiles bearing olfactory notes associated with the presence of fungi or, less likely, of prey captured by predatory arthropods (food sources of its pollinators) but offers a nectar reward upon insect arrival. Hence, there is a mismatch between the advertisement and the actual reward. Our results also suggest that the size of floral parts constitutes a mechanical filter where reciprocal fit between flower and insect structures ensures that only suitable pollinators can extract the pollinaria, a prerequisite for successful pollination.

Studies on neurobehavioural properties of Caralluma dalzielii N.E Br. aqueous aerial parts extract in mice.

ETHNOPHARMACOLOGICAL RELEVANCE: Caralluma dalzielii (Asclepiadiaceae) is a shrub used in folkloric medicine to treat epilepsy, pain and infertility in sub-Saharan Africa. Previous studies demonstrated its analgesic, antiulcer, anticonvulsant, and anti-inflammatory activities. AIM: This study aimed to determine the neurobehavioural properties of Caralluma dalzielii aqueous aerial parts extract (CDAE) in mice using standard experimental models. MATERIALS AND METHODS: Neurobehavioural activities of CDAE were evaluated (100, 200, and 400 mg/kg) in Swiss Albino mice using the beam walk, staircase, hole board, object recognition, open field assay, Y-maze and forced swimming tests. Phytochemical constituents were analysed using GC-MS. RESULTS: CDAE significantly increased the mean number of head dips, recognition index and spontaneous alternation in hole board (14.03 at 400 mg/kg and 6.01 in distilled water group; p < 0.05), object recognition (68.16% at 400 mg/kg compared with 51.66% of distilled water group) and Y maze (9.16 at 400 mg/kg as against 4.66 of distilled water group; p < 0.05) tests respectively. It decreased the rearing counts as well as the peripheral and central square crossing in the staircase (4.2 at 400 mg/kg as against 7.87 of the distilled water group; p < 0.05) and open field tests (central, 0.81; peripheral, 1.66 at 400 mg/kg as against central, 5.23; peripheral 11.83 of the distilled water control group; p < 0.05), respectively. There were no significant effects on beam walk assays and forced swim tests. The GC-MS analysis identified a hundred compounds in CDAE. Some compounds which have been reported to possess neurobehavioural activity that were identified include 3,5-Dimethylpyrazole, 2-Amino-5-methylbenzoic acid, Acetophenone, and Tetrahydropyran. CONCLUSION: CDAE demonstrated anxiolytic, anti-hyperactivity, and memory-improving effects in mice. The extract may possess GABAergic and glutamatergic properties. More studies are needed to confirm this. Isolation of the bioactive compounds is currently ongoing to unravel the bioactive constituents present in C. dalzielii extract.