Chemical constituents of Impatiens chapaensis Tard. and their α-glucosidase inhibition activities.

Sixteen compounds (1-16) were isolated from Impatiens chapaensis. Chemical structures were determined by spectroscopic analyses and comparisons with previously published data. This report is the first to identify compounds 1, 5-7, 10, 12-14, and 16 from the genus Impatiens. Seven chosen isolates (5, 7, 10, 11, 12, 15, and 16) were submitted for α-glucosidase inhibition assays with acarbose as the positive control (IC50 = 227.14 ± 13.71 µM). Flavonoid 5 exhibited a significant inhibitory effect (IC50 = 101.00 ± 9.01 µM).

Quality consistency evaluation of commercial Impatiens Caulis by integrating UPLC-QTOF-MS/MS chemical profiling and UPLC-DAD multi-components quantification approaches.

In this study, ultra-high performance liquid chromatography coupled with quadrupole time-of-flight mass spectrometry (UPLC-QTOF-MS/MS) and ultra-high performance liquid chromatography coupled with photo-diode array spectrometry (UPLC-DAD) were firstly integrated to qualitatively characterize the chemical profiles and quantitatively determine the major components in Impatiens Caulis (IC), a Chinese medicinal herb derived from the dried stem of Impatiens balsamina. The qualitative analysis revealed that there was no difference in chemical profiles of twenty commercial IC samples. A total of 45 components were characterized, there in 5 naphthoquinones, 3 coumarins, 5 phenolic acids, 12 flavonoids and 3 other compounds were identified definitely. However, the quantitative results showed a significant difference in these IC samples. In particular, the highest content of total quantified compounds was even 9.49 times of the lowest one. Furthermore, the average contents of these quantified compounds in twenty commercial IC samples had high values of relative standard deviation (RSD) ranged from 15.64% to 98.76%, suggesting a poor quality consistency in these commercial IC samples. Therefore, efficacy related chemical markers as well as the cultivation region, harvest time and/or post-harvest handling of IC should be further investigated for ensuring its quality and efficacy consistency.

Total Synthesis of (±)-Impatien A via Aza-Heck Cyclization.

The first total synthesis of the natural product impatien A is described. This concise synthesis features an aza-Heck cyclization to construct the complex spirocyclic ring system and provides a rare example of the use of aza-Heck cyclizations in complex molecule synthesis. To enable this key cyclization of an electrophilic nitrogen atom with a tetrasubstituted alkene, we utilized high-throughput experimentation to identify a new ligand and ultimately deliver impatien A in seven steps from known compounds.

Evaluation of antibacterial and acute oral toxicity of Impatiens tinctoria A. Rich root extracts.

The high prevalence of morbidity and mortality from bacterial infections, together with the growing threat of antibacterial resistance, necessitated the development of alternative new drugs from traditional medicine. In Ethiopia, Impatiens tinctoria A. Rich has been traditionally used for the treatment of fungal infections such as ringworms that cause tinea pedis and it have also different medical values. Scientific information on its biological activity against a broad range of bacteria and safety data is scant, compared to its folklore data. In this study, we evaluated antibacterial activities and acute oral toxicity of aqueous, ethanol and ethyl acetate root extracts of Impatiens tinctoria A. Rich. Aqueous, ethanol and ethyl acetate extracts of the plant were evaluated using agar hole diffusion and agar dilution methods. Biological activities of the plant extracts were expressed as a zone of inhibition diameter, minimum inhibitory concentration (mg/ml), and minimum bactericidal concentration (mg/ml). The safety studies were performed by oral acute toxicity study according to the organization of economic cooperation and development test Guidelines 420.Gram-positive bacteria were more susceptible to the extracts compared to gram-negative bacteria, especially against S. aureus and S. epidermidis, which are commonly found in the skin. Ethyl acetate extract was more potent than ethanol and aqueous extracts. The 50% lethal dose (LD50) of tested mice was above 9600 mg/kg. This study provides a scientific basis for the antibacterial activity of the root extracts of I. tinctoria A. Rich, where, the ethyl acetate extract showed the most promising activity. Therefore, the antibacterial potential and practical non-toxicity of the study plant extracts suggested the possibility of using it for the development of antimicrobial drugs by further studying the plant in different directions.

Chemical Composition and Bioactive Characterisation of Impatiens walleriana.

The attractive colour characteristics of the flowers of the species Impatiens walleriana have been arousing great interest in the food industry, which is looking for potential natural sources of colouring ingredients. In this sense, the present work focused on the chemical and bioactive characterization of pink and orange flowers of I. walleriana. The phenolic compounds were determined by HPLC-DAD-ESI/MS; in addition, different bioactivities (antioxidant, antimicrobial, anti-inflammatory and cytotoxicity) were also analysed. Both samples studied showed significant amounts of phenolic compounds, especially phenolic acids, flavonoids, and anthocyanins, which justifies the excellent performance in the different bioactivities studied. The orange variety, despite having a greater variety of phenolic compounds, showed a total amount of compounds lower than the pink variety. Overall, the flowers of I. walleriana emerge as a promising resource to be explored by the food industry.

Anti-inflammatory activity of saponins from roots of Impatiens parviflora DC.

Two triterpene saponins (IPS-1, IPS-2) for the first time were isolated from the roots of Impatiens parviflora DC. (Balsaminaceae). Their anti-inflammatory activity was evaluated by means of two in vitro models: anti-hyaluronidase and anti-denaturation assays. Both saponins were shown to be potent hyaluronidase inhibitors that affect the enzyme in a dose-dependent manner. The anti-hyaluronidase effect of IPS-2 (IC50 = 286.7 µg/mL) was higher than that of the reference drug: escin (IC50 = 303.93 µg/mL). Both saponins protected bovine serum albumin from heat-induced denaturation in a dose-dependent manner. IPS-1 demonstrated higher anti-denaturation effect (IC50 = 86.7 µg/ml) than IPS-2 (IC50 = 109.76 µg/mL) or the standard drug: acetylsalicylic acid (IC50 = 262.22 µg/mL). In conclusion, potent activity of IPS-1, IPS-2 in both in vitro assays shows that saponins from I. parviflora have anti-inflammatory activity. The obtained results allow to suggest that such compounds may be beneficial in inflammatory conditions, especially associated with excessive degradation of hyaluronic acid.

Phenolic constituents of the aerial parts of Impatiens glandulifera Royle (Balsaminaceae) and their antioxidant activities.

As a continuation of investigating Impatiens L. genus, eight flavonoids, eriodyctiol, eriodyctiol 7-O-ß-ᴅ-glucoside, kaempferol 3-O-ß-ᴅ-glucoside, kaempferol 3-O-ß-ᴅ-galactoside, kaempferol 3-rhamnosyl-di-glucoside, kaempferol 3-O-ß-ᴅ-rutinoside, quercetin 3-O-ß-ᴅ-glucoside and quercetin 3-O-ß-ᴅ-galactoside, two phenolic acids - p-hydroxybenzoic acid and protocatechuic acid, and 2-methoxynaphthalene-1,4-dione were isolated from the aerial parts of I. glandulifera collected in Poland. The structures of the compounds were established by analysis of their spectroscopic (1H and 13C NMR) and spectrometric (MS) data, as well as by comparison of these with those reported in the literature. Quercetin 3-O-ß-ᴅ-glucoside, kaempferol 3-O-ß-ᴅ-galactoside and kaempferol 3-O-ß-ᴅ-rutinoside were isolated for the first time from the investigated taxon. In addition, the antioxidant activities in different tests of all obtained compounds were evaluated. The results clearly showed that among analyzed constituents, quercetin 3-O-ß-ᴅ-glucoside exhibited antioxidant activity comparable or better than ascorbic acid and Trolox which were used as a positive control.

Preliminary Characterization and Bioactivities of Some Impatiens L. Water-Soluble Polysaccharides.

Preliminary characterization and bioactivity of water-soluble polysaccharides from four Impatiens species-I. glandulifera Royle, I. parviflora DC., I. balsamina L., and I. noli-tangere L.-were investigated. The yields of polysaccharides range widely from 1.97% for I. parviflora roots to 18.63% for I. balsamina aerial parts. SEC (Size exclusion chromatography) chromatograms show that all samples contained a low molecular weight part that consisted of components of similar molecular weight. The aerial parts and roots of I. balsamina, and I. glandulifera aerial parts had considerable amounts of high molecular weight components up to 2.3 MDa. The sugar composition analysis revealed that Impatiens polysaccharides consisted primarily of galactose, arabinose, rhamnose, mannose, xylose, and glucose. All polysaccharide fractions, except for I. parviflora roots, also contain galacturonic acid. Moreover, in vitro bioactivity of obtained polysaccharides were evaluated. The antioxidant activity was evaluated on the basis of 2,2-diphenyl-1-picrylhydrazyl (DPPH) and 2,2-azino-bis-(3-ethyl-benzthia-6-sulfonic acid) (ABTS) radical scavenging assays. The highest antioxidant activity was obtained for I. balsamina aerial parts and I. parviflora roots. Among the tested fractions, only the polysaccharides from I. glandulifera aerial parts were able to significantly decrease the production of IL-8 by 32.7 ± 10.5%. The results suggest that Impatiens species can be considered as a new source of antioxidants.

Anti-Neurodegenerative Biflavonoid Glycosides from Impatiens balsamina.

Four biflavonoid glycosides, balsamisides A-D (1-4), and nine known compounds (5-13) were obtained from the white petals of Impatiens balsamina. The 2D structures of the purified phytochemicals were established using conventional NMR techniques in addition to the new long-range HSQMBC NMR experiment. Acid hydrolysis followed by experimental and quantum-mechanics-based ECD data analysis permitted full configurational assignment of the purified metabolites. Compounds 1-13 were assessed for their potential to impede the generation of nitric oxide in lipopolysaccharide-stimulated BV2 cells. They were also investigated for potential neuroprotective activity using C6 cells and cytotoxicity against some human tumor cell lines, but were inactive (IC50 > 10 µM) against all the cell lines.

A new label-free screen for steroid 5α-reductase inhibitors using LC-MS.

Steroid 5α-reductase (S5αR) plays an important role in metabolizing testosterone into active androgen dihydrotestosterone (DHT) which is involved in many androgen dependent disorders, such as androgenic alopecia, benign prostatic hyperplasia and acne. The method for screening for S5αR inhibition is key in finding new antagonists. In this study, the label-free S5αR inhibitory assay using LC-MS was developed. S5αR type 1 enzyme was obtained from LNCaP prostate cancer cells. The enzymatic assay was optimised for enzyme-substrate (testosterone) concentration, NADPH-cofactor concentration, solvent tolerance, enzyme activity stability and incubation time. The developed assay was validated by measuring the signal to background ratio (S/B), the signal to noise ratio (S/N), the signal window (SW) and the zeta factor Z' in accordance with published bioassay guidelines. The enzymatic reaction was performed in 96-well plates and DHT formation was determined by LC-MS. S/B, S/N, SW and Z' factor were well above acceptable criteria and the reproducibility was good using Z' factor other 3days and further validated by dutasteride and finasteride inhibition. The method was successfully applied to quantify S5αR inhibitory activity of some Thai herbal extracts. Two plant extracts, Impatiens balsamina L. and Curcuma longa L. showed IC50 at 5.4±0.2 and 9.0±1.2µgmL-1 and are therefore promising sources of new S5αR inhibitors. The assay has high selectability and reproducibility and suited to medium throughput screening required by phytochemistry.

Comparison of the Essential Oil Composition of Selected Impatiens Species and Its Antioxidant Activities.

The present paper describes the chemical composition of the essential oils obtained by hydrodistillation from four Impatiens species, Impatiens glandulifera Royle, I. parviflora DC., I. balsamina L. and I. noli-tangere L. The GC and GC-MS methods resulted in identification of 226 volatile compounds comprising from 61.7%-88.2% of the total amount. The essential oils differed significantly in their composition. Fifteen compounds were shared among the essential oils of all investigated Impatiens species. The majority of these constituents was linalool (0.7%-15.1%), hexanal (0.2%-5.3%) and benzaldehyde (0.1%-10.2%). Moreover, the antioxidant activity of the essential oils was investigated using different methods. The chemical composition of the essential oils and its antioxidant evaluation are reported for the first time from the investigated taxon.

Glanduliferins A and B, two new glucosylated steroids from Impatiens glandulifera, with in vitro growth inhibitory activity in human cancer cells.

Impatiens glandulifera has been imported from Himalaya in Europe and is considered as an invasive alien plant whose spreading arouses increasing interest among scientific literature. Via anti-cancer bioguiding, two new glucosylated steroids, named glanduliferins A and B, were isolated from the dried stem of I. glandulifera plants, together with the well-known α-spinasterol and 2-methoxy-1,4-naphthoquinone, which are also isolated from roots and leaves. They were characterized as 17-(2-hydroxy-2-pentamethylcyclopropyl-ethyl)-10,13-dimethyl-2,3,4,5,6,9,10,11,12,13,14,15,16,17-tetradecahydro-1H-cyclopents[a]phenathren-3-O-(4-O-acetyl)-α-D-glucopyranoside and 17-(4-ethyl-1,5-dimethyl-hex-2-enyl)-10,13-dimethyl-2,3,4,5,6,9,10,11,12,13,14,15,16,17-tetradecahydro-1H-cyclopents[a]phenathren-3-O-(6-O-acetyl)-ß-D-glucopyranoside using various NMR and HRESIMS techniques and chemical methods. In vitro determination of the growth inhibitory activity of the four isolated compounds using the MTT colorimetric assay revealed mean IC50 growth inhibitory value of ~30 µM for glanduliferin A while glanduliferin B and α-spinasterol were poorly active till 100 µM. 2-methoxy-1,4-naphthoquinone revealed to be active in the single micromolar digit range as previously described. Quantitative videomicroscopy analyses of the effects of glanduliferins A and B suggested cytostatic rather than cytotoxic activity in U373 glioblastoma (GBM) cells.

Flavonoids from the flowers of Impatiens glandulifera Royle isolated by high performance countercurrent chromatography.

INTRODUCTION: Impatiens glandulifera Royle (Balsaminaceae) is an annual herb from the Himalaya region, currently widespread along European river systems and one of the most important neophyte invading plants in Germany. Exploring the effects of allelopathic plant chemicals is important for the understanding of its ecological impacts in the process of suppression of indigenous plant species. OBJECTIVE: To investigate the chemical composition of Impatiens glandulifera flowers (IGFs) using high performance countercurrent chromatography (HPCCC). METHODS: The flowers of Impatiens glandulifera were manually separated and extracted with ethanol. LC-ESI-MS/MS was used to characterise the crude extract of IGF. The various flavonoids detected were isolated by HPCCC using of methyl tert-butyl ether-acetonitrile-water (2:2:3, v/v/v). The combination of the data provided by preparative ESI-MS/MS metabolite profiling, LC-ESI-MS/MS, UV-vis and 1D/2D-NMR spectroscopic analysis was used to elucidate the structures of the isolated compounds. RESULTS: HPCCC runs led to the direct isolation of pure dihydromyricetin (ampelopsin), eriodictyol-7-O-glucoside, kaempferol-3-O-glucoside (astragalin) and kaempferol-3-O-6"-malonyl-glucoside, as well as the pre-purification of kaempferol-3-O-rhamno-rhamnosyldiglucoside, quercetin-3-O-galactoside (hyperoside), quercetin and kaempferol in a single step. CONCLUSION: This is the first report on the flavonoid composition of the species Impatiens glandulifera. The developed protocol was successfully used to isolate the main flavonoids from the crude extract of IGFs. This combined HPCCC and HPLC procedure could be applied to the fast fractionation and recovery of flavonoid derivatives of other plant extracts.

Effects of extended growth periods on subcellular distribution, chemical forms, and the translocation of cadmium in Impatiens walleriana.

Impatiens walleriana plants accumulate sufficiently high concentrations of cadmium (Cd) for this species to be considered a potential Cd hyperaccumulator. Rooted cuttings were grown hydroponically for 25 and 50 days in solutions spiked with various Cd concentrations. The subcellular distribution and chemical forms of Cd in different organs were analyzed, and its upward translocation was also assessed. The plants accumulated large amounts of Cd; the Cd concentration in the roots and shoots reached 120-1900 and 60-1600 mg/kg, respectively. Regardless of the growth period, the Cd accumulated in the roots was primarily compartmentalized in the soluble fraction or ethanol and deionized water extractable chemical forms with high migration abilities. Translocation to the shoots was followed by an association of Cd mainly in the cell wall or with pectate and protein. The roots' Cd showed a high migration capacity for predicting the shoots' Cd concentrations. Different exposure periods significantly affected the subcellular distribution of Cd in the stems, and thus the upward translocation.

In vitro anti-denaturation and anti-hyaluronidase activities of extracts and galactolipids from leaves of Impatiens parviflora DC.

The in vitro anti-denaturation and anti-hyaluronidase activities of Impatiens parviflora extracts and isolated galactolipids (MGDG-1, DGDG-1) were investigated. This is the first report on these compounds in I. parviflora. All extracts showed anti-hyaluronidase activity, but only methanolic extract from fresh leaves exhibited significant activity against heat-induced denaturation of BSA in a dose-dependent manner. At 500 µg/mL, the extract and the reference drug showed 79.05% and 99.81% inhibition of protein denaturation, respectively. These results indicate that fresh leaves of I. parviflora may be beneficial in inflammatory conditions, especially those associated with protein denaturation, such as rheumatoid arthritis. The study revealed that only MGDG-1 showed weak activity in anti-denaturation assay but both galactolipids were potent inhibitors of hyaluronidase. MGDG-1 completely inhibited the enzyme activity at the concentration of 127.9 µg/mL. These results indicate the potential of galactolipids in the treatment of diseases associated with the loss of hyaluronic acid.

[Chemical constituents from Impatiens pritzllii var. hupehensis].

Eight compounds were isolated from the 50% ethanol extract of Impatiens pritzllii var.hupehensis through various column chromatography methods including silica gel, Sephadex LH-20, and preparative HPLC. Their structures were elucidated as 2,6-dimethyl-2-vinyl-2,3,4,7-tetrahydrooxepine(1), 1,3,6-trihydroxy-7-methyl-anthraquinone(2),4-hydroxybenzaldehyde(3),4-(3-methoxy-4-hydroxyphenyl)-2-butanone(4), podophyllotoxin(5),scopoletin(6), α-spinasterol(7) and 3-O-ß-D-glucopyranosyl-α-spinasterol(8) based on the NMR and MS spectral data. Compound 1 is new compound and compounds 2-8 are isolated from this plant for the first time.

Depside derivatives with anti-hepatic fibrosis and anti-diabetic activities from Impatiens balsamina L. flowers.

Eighteen compounds (1-18), seven new (3-9) and eleven previously reported (1, 2, and 10-18), were isolated from the flowers of Impatiens balsamina (Linn). The structures of the isolated compounds were elucidated using different spectroscopic methods, including NMR (1D and 2D), UV, IR, and HR-ESI-MS. Analysis of the bioassay results showed the compounds had notable anti-hepatic fibrosis activity against murine Hepatic Stellate Cells (t-HSC/Cl-6) and anti-diabetics activity against α-glucosidase. Specifically, new compounds 7, 8, 9 showed significant inhibitory activity on t-HSC/Cl-6 cells with IC50 values of 42.12, 109.2, and 34.04 µg/mL respectively, while the IC50 values of positive control Silymarin and Fufang Biejia Ruangan Pian were 202.34 and 231.56 µg/mL, respectively. In addition, compounds 2, 4, 7, 8, 10, 11, 17, and 18 exhibited excellent α-glucosidase inhibitory activity. Among these compounds, 7 exhibited the highest activity with an IC50 value of 0.72 µg/mL, while the IC50 value of the positive control acarbose was 3.36 µg/mL. This is the first study evaluating the anti-hepatic fibrosis and anti-diabetic activities of compounds isolated from the flowers of I. balsamina.

Anti-inflammatory effect of Impatiens textori Miq. extract via inhibition of NLRP3 inflammasome activation in in vitro and in vivo experimental models.

ETHNOPHARMACOLOGICAL RELEVANCE: Impatiens textori Miq. (I. textori, Balsaminaceae) is a traditional medicinal herb used for centuries to treat several inflammatory related skin infections and allergic disorders in Asian countries. AIM OF THE STUDY: In this study, we elucidated the effects of whole plant extracts of I. textori on inflammasome activation using in vitro and in vivo models. MATERIALS AND METHODS: LPS-stimulated murine bone marrow macrophages were used to study the regulatory effect of I. textori extract (IT) on inflammasome activation. ATP, nigericin and MSU were used as danger-associated molecules to activate the NLRP3 inflammasome. An LPS-induced acute lung injury (ALI) mouse model was used to study the in vivo effect of IT on inflammasome activation. RESULTS: IT treated at 25, 50, and 100µg/mL concentrations suppressed interleukin-1ß secretion through the attenuation of NLRP3 inflammasome activation (p<0.001 at 100µg/mL) leading to the decreased amount of ASC oligomerization and caspase-1 maturation. For the in vivo model, IT inhibited the NLRP3 expression and cell recruitment at the lung tissue in the ALI mouse model. CONCLUSION: IT exhibited potent anti-inflammatory effects via the attenuation of NLRP3 inflammasome activation supporting the traditional claims and may provide a valuable therapeutic strategy in treating various inflammation-related disorders.

Nectar protein content and attractiveness to Aedes aegypti and Culex pipiens in plants with nectar/insect associations.

We chose five easily propagated garden plants previously shown to be attractive to mosquitoes, ants or other insects and tested them for attractiveness to Culex pipiens and Aedes aegypti. Long term imbibition was tested by survival on each plant species. Both mosquito species survived best on Impatiens walleriana, the common garden impatiens, followed by Asclepias curassavica, Campsis radicans and Passiflora edulis, which sponsored survival as well as the 10% sucrose control. Immediate preference for imbibition was tested with nectar dyed in situ on each plant. In addition, competition studies were performed with one dyed plant species in the presence of five undyed plant species to simulate a garden setting. In both preference studies I. walleriana proved superior. Nectar from all plants was then screened for nectar protein content by SDS-PAGE, with great variability being found between species, but with I. walleriana producing the highest levels. The data suggest that I. walleriana may have value as a model plant for subsequent studies exploring nectar delivery of transgenic mosquitocidal proteins.