Afzelin Research Articles

Assessment of the health benefits of phytochemicals in Cynometra cauliflora based on an in silico study against Alzheimer’s disease

Aim: Cynometra cauliflora (namnam) belongs to the family Fabaceae and is native to eastern Peninsular Malaysia. It grows well with an annual rainfall of 1,500–2,000 mm. Even though a considerable amount of research has been carried out with C. caulifora, there is a dearth of information about biomolecules that may pave the way for drug discoveries and food supplements, which is a gap addressed in this study. Methods: The study presented in this paper has identified several antimicrobial, antioxidant, and anti-inflammatory substances, and an in silico approach was used to understand the behaviors of kaempferol-3-O-rhamnoside (K-3-Rh) and β-sitosterol acetate against Alzheimer’s disease (AD). The molecular dynamics (MD) simulations were performed with the selected protein ligand complex of two natural molecules and the synthetic ligand to analyze the dynamic behaviors and binding free energy throughout the 100 ns simulation time. Further, both natural molecules that were investigated comply with Lipinski’s drug-likeness rules. Results: The docking scores of both K-3-Rh and sitosterol were found to be compatible with the synthetic AD drug molecules [donepezil analogue (H0L)] used as a reference in the study. Hence, the phytochemicals of Cynometra caulifora showed comparatively similar potency against acetylcholinesterase (AChE). Conclusions: Overall, the potential binding affinity from molecular docking and static thermodynamics features from MD simulation suggest that K-3-Rh and β-sitosterol acetate could be considered as a potential therapeutic lead to inhibit AChE leading for AD treatment.

Kaempferol 3-Rhamnoside on Glutamate Release from Rat Cerebrocortical Nerve Terminals Involves P/Q-Type Ca2+ Channel and Ca2+/Calmodulin-Dependent Protein Kinase II-Dependent Pathway Suppression.

Excess synaptic glutamate release has pathological consequences, and the inhibition of glutamate release is crucial for neuroprotection. Kaempferol 3-rhamnoside (KR) is a flavonoid isolated from Schima superba with neuroprotective properties, and its effecton the release of glutamate from rat cerebrocortical nerve terminals was investigated. KR produced a concentration-dependent inhibition of 4-aminopyridine (4-AP)-evoked glutamate release with half-maximal inhibitory concentration value of 17 µM. The inhibition of glutamate release by KR was completely abolished by the omission of external Ca2+ or the depletion of glutamate in synaptic vesicles, and it was unaffected by blocking carrier-mediated release. In addition, KR reduced the 4-AP-evoked increase in Ca2+ concentration, while it did not affect 4-AP-evoked membrane potential depolarization. The application of selective antagonists of voltage-dependent Ca2+ channels revealed that the KR-mediated inhibition of glutamate release involved the suppression of P/Q-type Ca2+ channel activity. Furthermore, the inhibition of release was abolished by the calmodulin antagonist, W7, and Ca2+/calmodulin-dependent protein kinase II (CaMKII) inhibitor, KN62, but not by the protein kinase A (PKA) inhibitor, H89, or the protein kinase C (PKC) inhibitor, GF109203X. We also found that KR reduced the 4-AP-induced increase in phosphorylation of CaMKII and its substrate synapsin I. Thus, the effect of KR on evoked glutamate release is likely linked to a decrease in P/Q-type Ca2+ channel activity, as well as to the consequent reduction in the CaMKII/synapsin I pathway.

Development of a new validated HPLC method for the chemical specification of Rosa damascena petals

Economical and fast analytical methods are required to determine the content of herbs and herbal medicine. With the increasing interest in rose tea and products prepared from rose flower extracts, it has emerged that products prepared from dried rose petals and rose flower extracts should have certain characteristics. In the European Pharmacopeia, there is no specific method to meet the specific needs of the industry. Therefore, in this study, a simple, cheap, fast and reliable RP-HPLC-DAD method was developed and validated for the identification and quantification of flavonoids in the methanol extract of Rosa damascena Mill. (RD) petals. 10 different RD petal samples obtained from Turkey (Isparta), Pakistan and different parts of Iran were studied and compared with fingerprinting. Several trials were conducted to identify the most robust and consistent HPLC method. Separation of flavonoids was achieved on a reversed-phase C18 column kept at 25 °C by gradient elution with a flow rate of 1.2 mL/min, injection volume of 10 µL and detection at 330 nm. Six different flavonol glycosides were identified which are kaempferol 3-O-glucoside (K3GLU), kaempferol 3-O-galactoside (K3GAL), kaempferol 3-O-rhamnoside (K3RHA), quercetin 3-O-glucoside (Q3GLU), quercetin 3-O-galactoside (Q3GAL), quercetin 3-O-rhamnoside (Q3RHA). K3GLU was determined to be the most suitable compound as a marker and was used for quantification and validation studies. Standard curve of this compound was plotted to calculate quantification. K3GLU amount was found the highest in Isparta rose with 0.7047%. Various validation parameters were done, and the method was found to be specific, stable, linear, sensitive, accurate, precise and robust to determine the chemical specification of RD petals.

Diuretic and Renal Protective Effect of Kaempferol 3-O-Alpha-l-rhamnoside (Afzelin) in Normotensive and Hypertensive Rats

Our previous study showed that kaempferitrin, the main flavonoid from Bauhinia forficata Link leaves, induces diuresis and saluresis when orally given to rats. Since afzelin (AFZ) and kaempferol (KFL) are active compounds from the biometabolism of kaempferitrin, the diuretic and renal protective properties of these two compounds were evaluated. While the acute treatment with AFZ evoked a diuretic action associated with an increase in Cl- excretion and a Ca2+-sparing effect, KFL did not present any activity. The pretreatment with a muscarinic receptor blocker or with an inhibitor of the cyclooxygenase fully avoided AFZ-induced diuresis. AFZ also induced a prolonged (7-day treatment) diuretic effect in normotensive (NTR) and hypertensive rats (SHR), with an increase of urinary Na+ and Cl- excretion, while it decreased the elimination of Ca2+. AFZ was able to decrease ROS and nitrite generation on kidney homogenates in comparison with the SHR group treated with the vehicle, as well as mitigated the changes in the renal corpuscle region (glomerulus and Bowman's capsule). Moreover, AFZ significantly reduced calcium oxalate crystal formation in urine, with inhibition rates of 41% for the NTR and 92% for the SHR group. Taken together, this study shows that AFZ exerts acute and prolonged diuretic effects plus protective renal properties.

A natural small molecule induces megakaryocytic differentiation and suppresses leukemogenesis through activation of PKCδ/ERK1/2 signaling pathway in erythroleukemia cells

Kaempferol-3-O-rhamnoside (KOR) has multiple potency involved in anti-cancer, anti-inflammatory and antibacterial actions. However, the potential roles of KOR and the analogues isolated from the leaves of Cyclocarya paliurus in anti-erythroleukemia remain unclear. In the present study, KOR and the two analogues (Kaempferol-3-O-(4″-O-acetyl-a-L-rhamnopyranoside) (KLR) and (kaempferol-3-O-α-L-(4″-E-p-coumaroyl) rhamnoside) (KCR) were isolated from leaves of Cyclocarya paliurus. Cell viability assay showed that KCR exerted an excellent anti-erythroleukemia activity. We observed that KCR not only significantly increased the percentage of G2 phase and apoptotic cells compared with control group, but also induced megakaryocytic differentiation in HEL and K562 cells by flow cytometry, indicating that KCR might inhibit cell proliferation through inducing differentiation-mediated apoptosis and cell cycle arrest. Mechanism investigation revealed that KCR treatment obviously increased phosphorylation levels of PKCδ and ERK1/2 as well as GATA1 expression. Taken together, these findings demonstrate that KCR induces megakaryocytic differentiation and suppresses leukemogenesis at least partly through activation of PKCδ/ERK1/2 signaling pathway in erythroleukemia cells. KCR may also serve as a promising natural compound for human erythroleukemia treatment.

Biological evaluation and molecular docking study of metabolites from Salvadora Persica L. Growing in Egypt

Background: Methicillin-resistant Staphylococcus aureus (MRSA) is a resistant staph bacterium to several antibiotics causing several lives-threating diseases such as pneumonia and sepsis. Meswak, Salvadora persica, exhibited promising antimicrobial properties before. Objective: Exploring the anti-MRSA activity of S. persica L. metabolites and its mechanism of action on a molecular level. Materials and Methods: Structure elucidation of the isolated metabolites was carried out by spectroscopic data (one-dimensional and two-dimensional nuclear magnetic resonance). The biological activities of the isolated metabolites against MRSA were evaluated and the molecular mode of action against the dehydrosqualene synthase enzyme have been done. Results: Four compounds have been isolated and identifies to be; apigenin (1), luteolin (2), astragalin (3), and kaempferol-3-O-rhamnoside (4). Compounds 1–4 showed good anti-MRSA activities with IC50 values of 10.3, 11.5, 3.5, and 4.5 μg/mL, respectively. In consistent, astragalin and kaempferol-3 rhamnoside showed close high docking scores. Herein, we are reporting the molecular determinates of activity of these new scaffolds as anti-MRSA, which would be of great importance to developing new anti-MRSA candidates. Abbreviations Used: 1D: One-dimensional; 2D: Two-dimensional; CC: Column chromatography; COSY: Correlations spectroscopy; DMSO: Dimethyl sulfoxide; HMBC: Heteronuclear multiple-bond correlation experiment; HRESIMS: High-resolution electrospray ionization mass spectrometry; HSQC: Heteronuclear single-quantum correlation; IR: Infrared; MRSA: Methicillin-resistant Staphylococcus aureus; NMR: Nuclear magnetic resonance; RP: Reversed phase; TLC: Thin-layer chromatography; UV: Ultraviolet; VLC: Vacuum liquid chromatography.

Phytochemical Analysis of Agrimonia pilosa Ledeb, Its Antioxidant Activity and Aldose Reductase Inhibitory Potential.

The aim of this study was to determine aldose reductase (AR) inhibitory activity and 1,1-diphenyl-2-picrylhydrazyl (DPPH) free radical scavenging activity of compounds from Agrimonia pilosa Ledeb (AP). We isolated agrimoniin (AM), four flavonoid glucosides and two flavonoid glucuronides from the n-butanol fraction of AP 50% methanol extract. In addition to isolated compounds, the AR-inhibitory activity and the DPPH free radical scavenging activity of catechin, 5-flavonoids, and 4-flavonoid glucosides (known components of AP) against rat lens AR (RLAR) and DPPH assay were measured. AM showed IC50 values of 1.6 and 13.0 μM against RLAR and DPPH scavenging activity, respectively. Additionally, AM, luteolin-7-O-glucuronide (LGN), quercitrin (QU), luteolin (LT) and afzelin (AZ) showed high inhibitory activity against AR and were first observed to decrease sorbitol accumulation in the rat lens under high-sorbitol conditions ex vivo with inhibitory values of 47.6%, 91.8%, 76.9%, 91.8% and 93.2%, respectively. Inhibition of recombinant human AR by AM, LGN and AZ exhibited a noncompetitive inhibition pattern. Based on our results, AP and its constituents may play partial roles in RLAR and oxidative radical inhibition. Our results suggest that AM, LGN, QU, LT and AZ may potentially be used as natural drugs for treating diabetic complications.

Antidiabetic activity of Sedum dendroideum: metabolic enzymes as putative targets for the bioactive flavonoid kaempferitrin.

The aim of this study was to evaluate the antidiabetic potential of a leaf extract and flavonoids from Sedum dendroideum (SD). Additionally, our goals were to establish a possible structure/activity relationship between these flavonoids and to assess the most active flavonoid on the glycolytic enzyme 6-phosphofructo-1-kinase (PFK). SD juice (LJ), a flavonoid-rich fraction (BF), and separately five flavonoids were evaluated intraperitoneally for their acute hypoglycemic activity in normal and streptozotocin-induced diabetic mice. First, the major flavonoids kaempferol 3,7-dirhamnoside or kaempferitrin (1), kaempferol 3-glucoside-7-rhamnoside (2), and kaempferol 3-neohesperidoside-7-rhamnoside (3) were tested. Then, the monoglycosides kaempferol 7-rhamnoside (5) and kaempferol 3-rhamnoside (6) were assayed to establish their structure/activity relationship. The effect of 1 on PFK was evaluated in skeletal muscle, liver, and adipose tissue from treated mice. LJ (400 mg/kg), BF (40 mg/kg), and flavonoid 1 (4 mg/kg) reduced glycemia in diabetic mice (120 min) by 52, 53, and 61%, respectively. Flavonoids 2, 3, 5, and 6 were inactive or showed little activity, suggesting that the two rhamnosyl moieties in kaempferitrin are important requirements. Kaempferitrin enhanced the PFK activity chiefly in hepatic tissue, suggesting that it is able to stimulate tissue glucose utilization. This result is confirmed testing kaempferitrin on C2C12 cell line, where it enhanced glucose consumption, lactate production, and the key regulatory glycolytic enzymes. The hypoglycemic activity of kaempferitrin depends on the presence of both rhamnosyl residues in the flavonoid structure when intraperitoneally administered. Our findings show for the first time that a flavonoid is capable of stimulating PFK in a model of diabetes and that kaempferitrin stimulates glucose-metabolizing enzymes. This study contributes to the knowledge of the mechanisms by which this flavonoid exerts its hypoglycemic activity.

Phytochemical, cytotoxic, hepatoprotective and antioxidant properties of Delonix regia leaves extract

Hepatocellular carcinoma is considered the third most common cause of cancer-related death worldwide. Thus, the present study was designed to test for the first time the putative cytotoxic effect of Delonix regia extract, besides its hepatoprotective activity. In this context, this study targets four specific aims; first, the phytochemical investigation of D. regia extract which led to the isolation of seven flavonoid glycosides; Kaempferol 3-rhamnoside 1, Quercetin 3-rhamnoside 2, Kaempferol 3-glucoide 3, Kaempferol 3-rutinoside 4, Kaempferol 3-neohesperidoside 5, Quercetin 3-rutinoside 6 and Quercetin 3-glucoside 7. Second, the evaluation of in vitro cytotoxic activity of the extract, where the extract exhibited a potent cytotoxic effect against HepG2 cell line. Third, the hepatoprotective activity was investigated using carbon tetrachloride (CCl4)-induced liver injury. The plant extract at dose of 50, 100 and 200 mg/kg body weight reduced serum aspartate aminotransferase, alanine aminotransferase and alkaline phosphatase as well as total and direct bilirubin in a dose dependent manner. The fourth aim was the investigation of the antioxidant activity of the extract as the treatment of rats with the extract at different doses significantly increased the liver tissue level of superoxide dismutase, catalase, reduced glutathione and total antioxidant capacity and decreased the level of malondialdehyde as compared to CCl4 treated group. The current findings concluded that the extract of D. regia possessed not only a significant anticancer effect against HepG2 cells, but also an effective and a dose dependent hepatoprotective and antioxidant activities due to the presence of flavonoids content.

Slantingly cross loading sample system enables simultaneous performance of separation and mixture to detect molecular interactions on thin-layer chromatography

Anthocyanins are major flower pigments that can be affected by copigments, colorless compounds that can modify anthocyanin coloration to more intense and bluer. Thin-layer chromatography (TLC) is an available technique to separate and analyze anthocyanins and copigments. To easily and comprehensively detect copigments, we added function of mixture of compounds to TLC; by slantingly cross loading samples on TLC, compounds are symmetrically developed at various angle lines from the upper origin to individual Rf values and cross each other in an orderly fashion, where mixture is simultaneously performed with separation. Occurrence of copigments can be detected as a coloration change on the developed line of anthocyanin. Pink sweet pea (Lathyrus odoratus L.) petals were analyzed by the cross-TLC and a more intense spot and a paler spot on the anthocyanin line were detected. As each spot overlapped with an ultraviolet absorbance line, each of these ultraviolet absorption compounds was purified and identified as kaempferol 3-rhamnoside and 2-cyanoethyl-isoxazolin-5-one, respectively. Whereas kaempferol 3-rhamnoside is a flavonoid and had a general copigment effect of more intense and bluer coloration change, 2-cyanoethyl-isoxazolin-5-one is a compound whose structure is outside of conventional categories of copigments and had a novel effect to change anthocyanin coloration paler while maintaining color tone. We determined that the search for copigments should be carried out without pre-existing prediction of structures and effects. We have shown that slantingly cross loading samples system on plate-type chromatography is an effective technique for such comprehensive analysis of molecular interaction.

Comparison of Antioxidant and Antimicrobial Activities of Methanolic Extracts of the Artemisia sp. Recovered by Different Extraction Techniques

The polyphenol content, antioxidant and antimicrobial activities of the extracts obtained by classical, ultrasonic and Soxhlet extractions from dry aerial parts of two Artemisia species ( Artemisia vulgaris and Artemisia campestris) were compared. Ultrasound positively affected the yield of extractive substance and the kinetics of extraction, but the extract obtained by the classical extraction showed the highest antioxidant activities and contained higher total contents of phenolic compounds and flavonoids than the extracts obtained by two other extraction techniques. Both flavonoid aglycones (apigenin, quercetin, quercetin 3,37prime;-dimethyl ether) and flavonoid glycosides (rutin, hyperoside and kaempferol 3-rhamnoside) were identified by thin layer chromatograph (TLC) analysis in the extracts from both species. A. campestris extracts were richer in quercetin than A. vulgaris and its antimicrobial activity was also better than A. vulgaris. Extracts obtained from both species were found to be more effective on the tested yeasts than bacteria. The kinetics of the total extractive substances, such as phenolic, flavonoids and quercetin extraction, was successfully described by the model of unsteady-state diffusion.

Online RP-HPLC-DPPH Screening Method for Detection of Radical-Scavenging Phytochemicals from Flowers of Acacia confusa

Acacia confusa is traditionally used as a medicinal plant in Taiwan. In this study, phytochemicals and antioxidant activities of extracts from flowers of A. confusa were investigated for the first time. In addition, a rapid screening method, online RP-HPLC-DPPH system, for individual antioxidants in complex matrices was developed. Accordingly, six antioxidants including gallic acid ( 1), myricetin 3-rhamnoside ( 2), quercetin 3-rhamnoside ( 3), kaempferol 3-rhamnoside ( 4), europetin 3-rhamnoside ( 5), and rhamnetin 3-rhamnoside ( 6) were detected using the developed screening method. Of these, compounds 2, 3, and 5 were found to be major bioactive phytochemicals, and their contents were determined as 11.3, 6.7, and 8.7 mg/g of crude extract, respectively. By comparison with quercetin, a well-known antioxidant, these compounds had the order of compound 2 > compound 5 > quercetin > compound 3 for DPPH radical-scavenging activity. Their IC 50 values were 3.0, 3.2, 4.5, and 7.4 microM, respectively. Moreover, the same order was observed for superoxide radical-scavenging activity, and their IC50 values were 2.6, 2.7, 4.3, and 5.3 microM, respectively. However, for lipid peroxidation, quercetin, an aglycon, showed the best inhibitory activity. The IC50 values of quercetin, compound 2, compound 5, and compound 3 were 46.7, 88.5, 90.7, and 124.6 microM, respectively. These results indicated that a rhamnoside at the C3 position of flavonoids had a negative effect on radical-scavenging activity and antilipid peroxidation. In contrast, the number of hydroxyl groups on the B-ring exhibited a positive relationship with their inhibitory activities.

Hazel ( Corylus avellana L.) leaves as source of antimicrobial and antioxidative compounds

Aqueous extracts of leaves of different hazel ( Corylus avellana L.) cultivars (Cv. M. Bollwiller, Fertille de Coutard and Daviana), were analysed by reversed-phase HPLC/DAD for the definition of their phenolic composition. Antioxidant potential was assessed by the reducing power assay, and the scavenging effect on DPPH (2,2-diphenyl-1-picrylhydrazyl) radicals and β-carotene linoleate model system. Their antimicrobial capacity was also tested against Gram positive ( Bacillus cereus, Bacillus subtilis, Staphylococcus aureus) and Gram negative bacteria ( Pseudomonas aeruginosa, Escherichia coli, Klebsiella pneumoniae) and fungi ( Candida albicans, Cryptococcus neoformans). Eight phenolic compounds were identified: 3-, 4- and 5-caffeoylquinic acids, caffeoyltartaric acid, p-coumaroyltartaric acid, myricetin-rhamnoside, quercetin 3-rhamnoside and kaempferol 3-rhamnoside. A p-coumaric acid, three myricetin and one quercetin derivatives were also detected. The hazel leaves extract presented high antioxidant activity in a concentration-dependent way, in general with similar behaviour of all cultivars. Gram positive bacteria revealed to be very sensitive to hazel leaf extract (MIC 0.1 mg/ml for B. cereus and S. aureus and 1 mg/ml for B. subtilis). However, Gram negative and the fungi displayed much lower sensitivity, being P. aeruginosa and C. albicans resistant at 100 mg/ml. Cv. M. Bollwiller exhibited the most potent antimicrobial activity.

Phenolic profile of hazelnut (Corylus Avellana L.) leaves cultivars grown in Portugal

In this study, phenolic compounds of hazelnut leaves of 10 different cultivars with the same cultural, geographical, geological and climatic conditions were analyzed by HPLC/DAD and HPLC/DAD/MS/MS – ESI. Eight phenolic compounds (3-caffeoylquinic acid, 5-caffeoylquinic acid, caffeoyltartaric acid, p-coumaroyltartaric acid, myricetin 3-rhamnoside, quercetin 3-glycoside, quercetin 3-rhamnoside and kaempferol 3-rhamnoside) were identified and quantified. All of the analyzed samples showed a similar phenolic profile, in which myricetin 3-rhamnoside and quercetin 3-rhamnoside were the major compounds and caffeoyltartaric and p-coumaroyltartaric acids were present in vestigial amounts.

Flavonol glycosides of Warburgia ugandensis leaves

Four new flavonol glycosides: kaempferide 3-O-β-xylosyl (1→2)-β-glucoside, kaempferol 3-O-α-rhamnoside-7,4′-di-O-β-galactoside, kaempferol 3,7,4′-tri-O-β-glucoside and quercetin 3-O-[α-rhamnosyl (1→6)] [β-glucosyl (1→2)]-β-glucoside-7-O-α-rhamnoside, were characterized from a methanolic leaf extract of Warburgia ugandensis. The known flavonols: kaempferol, kaempferol 3-rhamnoside, kaempferol 3-rutinoside, myricetin, quercetin 3-rhamnoside, kaempferol 3-arabinoside, quercetin 3-glucoside, quercetin, kaempferol 3-rhamnoside-4′-galactoside, myricetin 3-galactoside and kaempferol 3-glucoside were also isolated. Structures were established by spectroscopic and chemical methods and by comparison with authentic samples.

Coumarin Glycoside from Cissus Sicyoides

From the aerial parts of Cissus sicyoides , a new coumarin glycoside 5,6,7,8-tetrahydroxycoumarin-5 g -xylopyranoside was obtained together with known coumarin sabandin, two flavonoids kaempferol 3-rhamnoside and quercetin 3-rhamnoside and two steroids, sitosterol and 3 g - O - g - d -glucopyranosylsitosterol. The structure of compounds was elucidated by spectral analyses.

Estrogenic Flavonoids from Artemisia vulgaris L.

The comprehensive quantitative analysis of the flavonoid chemistry of Artemisia vulgaris L., a plant used as an emmenagogue in traditional medicine, is presented in conjunction with an evaluation of its estrogenic activity. Twenty known flavonoids were isolated and identified as tricine, jaceosidine, eupafolin, chrysoeriol, diosmetin, homoeriodictyol, isorhamnetin, apigenin, eriodictyol, luteolin, luteolin 7-glucoside, kaempferol 3-glucoside, kaempferol 7-glucoside, kaempferol 3-rhamnoside, kaempferol 3-rutinoside, quercetin 3-glucoside, quercetin 3-galactoside, quercetrin, rutin, and vitexin. The most abundant compounds were eriodictyol and luteolin. The estrogenic activity of all flavonoids was assayed by employing a reconstituted estrogen transcription unit in Saccharomyces cerevisiae transformed with both a human estrogen receptor expression plasmid and a reporter plasmid. Two flavonoids, eriodictyol and apigenin, were able to induce the transcription of the reporter gene in transgenic yeast. The transcriptional activity increased proportionally with increased amounts of purified eriodictyol or apigenin added to the yeast cells.

Flavonoid O-Glycosides from the leaves of Morinda morindoides

Eight known flavonoids: quercetin, quercetin 7,4′-dimethylether, luteolin 7-glucoside, apigenin 7-glucoside, quercetin 3-rhamnoside, kaempferol 3-rhamnoside, quercetin 3-rutinoside, kaempferol 3-rutinoside, and a new glycoside, chrysoeriol 7-neohesperidoside, were isolated from the leaves of Morinda morindoides. Their structures were established by the combined use of chemical and spectroscopic methods.

Two phloroglucinol glucosides, flavan gallates and flavonol glycosides from Sedum sediforme flowers

Two new compounds, whose structures were elucidated by spectroscopic means as 1-β- d-gluco pyranosyloxy-3-methoxy- 5-hydroxybenzene and (2 R,3 R)-7,4′-dihydroxy-5,3′,5′-trimethoxyflavan 3- O-gallate, were isolated from Sedum sediforme flowers. They were accompanied by 1-β- d-glucopyranosyloxy-3,5-dihydroxybenzene, limocitrin 3- glucoside, kaempferol 3-rhamnoside, quercetin 3-rhamnoside, myricetin 3-rhamnoside, (−)-epicatechin 3-gallate, (−)- epigallocatechin 3-gallate and gallic acid.

Flavonoid profiles of new zealand Libocedrus and related genera

Flavonoids common to both Libocedrus bidwillii and L. plumosa, which were sampled throughout New Zealand, are: kaempferol and quercetin 3-rhamnoside, kaempferol and quercetin 3-rhamnoside-7-glucoside, quercetin 3-glucoside, apigenin and luteolin 7-glucoside, luteolin 7-di- (and tri)-glucosides, amentoflavone, 7- O-methylamentoflavone, 2,3-dihydroamentoflavone, and the new flavonoids, 8-hydroxyapigenin and 8-hydroxyluteolin 7- O-xylosides and 7- O-methyl-2,3-dihydroamentoflavone. Libocedrus plumosa is distinguished by the additional accumulation of myricetin 3-rhamnoside, and L. bidwillii by the presence of quercetin 3- O-α-[2- p-hydroxybenzoyl-4- O- p-coumaroylrhamnopyranoside] which was found amongst the biflavones. A chromatographic survey of some related non-New Zealand species and genera is also reported.