Chemical constituents from the leaves of Crataegus pinnatifida Bge

The phytochemical investigations on the leaves of Crataegus pinnatifida led to the isolation of 20 compounds, including seven triterpenoids (1-7), three hydroxycinnamic acids (8-10), three lignans (11-13) and seven flavonoids (14-20). All chemical structures were established on the basis of NMR (1H NMR, 13C NMR) spectroscopic data. Meanwhile, compounds 3-12 are reported for the first time from Crataegus genus. In addition, compounds 10-11 are isolated from the family Rosaceae for the first time. On the basis of chemical research, the chemotaxonomic significance of the isolated compounds has been discussed.     

Flavonoid ketohexosefuranosides from the leaves of Crataegus pinnatifida Bge. var. major N.E.Br.

Four flavonoid ketohexosefuranosides, pinnatifinoside A, pinnatifinoside B, pinnatifinoside C, and pinnatifinoside D were isolated from the leaves of Crataegus pinnatifida Bge. var. major N.E.Br. Their structures were elucidated by spectroscopic analysis (UV, IR, MS and 1D, 2D NMR) and chemical evidence.     

Identification of potential and selective collagenase,gelatinase inhibitors from Crataegus pinnatifida

Four oligomeric procyanidins were isolated from the MeOH extracts of the leaves of Crataegus pinnatifida (Rosaceae). Investigation of collagenase and gelatinase inhibitory natural components afforded four oligomeric procyanidins. Of these, 2 and 3 exhibited collagenase inhibitory activity (IC₅₀) at a concentration of less than 1 μM, and 3 showed gelatinases A and B inhibitory activity (IC₅₀) at 0.4 and 2.3 μM, respectively.     

Chiral resolution and neuroprotective activities of enantiomeric dihydrobenzofuran neolignans from the fruit of Crataegus pinnatifida

Three pairs of enantiomeric dihydrobenzofuran neolignans (1a/1b-3a/3b) including four new compounds (1a/1b and 2a/2b) were isolated from the fruit of Crataegus pinnatifida. Their structures including the absolute configurations were elucidated by extensive spectroscopic analyses and comparison between the experimental measurements of electronic circular dichroism (ECD) and the calculated ECD spectra. Additionally, all the enantiomeric neolignans were investigated for their neuroprotective activities against H₂O₂-induced cell injury in human neuroblastoma SH-SY5Y cells. It was found that enantiomers 1a and 1b displayed different degrees of neuroprotective activities, and the results showed enantioselectivity, in which that 1b exhibited noticeable neuroprotective activity, while its enantiomer 1a only exhibited obvious protective effect at lower concentration. Further study demonstrated that the potential protective activities of compounds appeared to be mediated via suppressing cell apoptosis.     

不同时期山里红叶片中多元酚类成分含量的测定

The content of polyphenolic compounds including chlorogenic acid, vitexin-4＂-O-glucoside, vitexin rhamnoside, rutin, vitexin, hyperoside in leaf of Crataegus pinnatifida Bunge var. major N. E. Br. at different times was determined by HPLC. The results show that the content of polyphenolic compounds in different times is various. In April, the total content of polyphenolic compounds and the contents of chlorogenic acid, vitexin-4＂-O-glucoside, vitexin rhamnoside, rutin reach the peak. And the content of every compound and the total content of these compounds decrease gradually with the plant growing, and reach the lowest point in July to August. Therefore, in order to extract polyphenolic compounds, the optimal harvest time for C. pinnatifida var. major leaf is April.     

超声法提取山里红叶总黄酮及其抗氧化活性研究

采用超声辅助提取法从山里红叶中提取总黄酮。通过Box Behnken实验设计(BBD)结合响应面法(RSM)来优化超声提取的条件。影响山里红叶总黄酮提取效率的4个主要变量为液固比,温度,乙醇浓度和时间,得到的最佳值分别为15,40℃,40%,32 min。在此条件下,总黄酮的产率为15.50 mg·g^-1。体外抗氧化实验表明,山里红叶提取物的DPPH自由基清除能力为0.69 mg·mL^-1(以IC₅₀值表示) ,与传统的浸渍提取和热回流提取方法相比,超声提取的方法具有更好的抗氧化活性。实验结果表明超声提取法适用于提取山里红叶中的总黄酮,并且其提取物具有较好的抗氧化活性。     

Isolation and identification of oligomeric procyanidins from Crataegus leaves and flowers

Oligomeric procyanidins were isolated from the leaves and flowers of hawthorn (Crataegus laevigata). A trimer, epicatechin-(4β→8)-epicatechin-(4β→6)-epicatechin, and a pentamer consisting of (−)-epicatechin units linked through C-4β/C-8 bonds have been isolated from hawthorn for the first time, in addition to known procyanidins including dimers B-2, B-4 and B-5, trimers C-1 and epicatechin-(4β→6)-epicatechin-(4β→8)-epicatechin, and tetramer D-1. A fraction containing a hexamer was also found.     

山楂叶总黄酮生长积累动态及提取工艺研究

对山楂叶总黄酬生长积累动态及提取工艺进行了研究,结果表明：（1）年生长周期中,山楂叶总黄酮含量有两个高峰期．其中第一个生长高峰期（6月15日～8月1日）峰值较高,持续时间较长;（2）各因素对山楂叶总黄酮的提取率影响是不均等的,影响最大的是料液比,其次是温度和时间。最佳提取工艺为：80Ｃ下,用碱度为0．25％的氢氧化钠乙醇溶液（50％乙醇）回流提取2次,每次lh．料液比为l：20。     

Phytochemical composition,antioxidant activity and neuroprotective effect of Crataegus pinnatifida fruit

Various neurodegenerative diseases e.g., Alzheimer's affect many elderly people that eventually leads to disability and premature death. No effective treatment for these neurodegenerative diseases has been developed yet. Oxidative stress-mediated neurodegeneration is one of the key pathophysiological factors involved in these diseases. Since numerous botanic components are well-known potent antioxidants, in this study, we aim to examine the neuroprotective effects of phytochemical compositions from the water, methanolic, and 95% ethanolic extracts of the Crataegus pinnatifida fruit against hydrogen peroxide (H₂O₂)-induced cytotoxicity in PC12 neuronal cells. Our results revealed that the methanolic extract showed the most favorable antioxidant activities in scavenging various sources of free radicals. All three extracts concentration (0.5–5 μg/ml)-dependently protected PC12 against H₂O₂-induced cell death with the methanolic extract being the most potent one. Component elucidation revealed that the methanolic extract contained the greatest amounts of total phenolic compounds, flavonoids and tannin content. Conversely, the water soluble and 95% ethanolic extracts yielded a comparable amount of total triterpenoid. Our results indicated that methanolic and 95% ethanolic extracts of C. pinnatifida fruit show the potential to be novel neuroprotective agents to be considered in nutraceutical products for preventing oxidative-related disorders. Further investigation is necessary to verify the neuroprotective efficacy and mechanisms in vivo.     

测定山楂及提取物总三萜酸的含量

目的:测定山楂及其提取物的总三萜酸的含量.方法:选用熊果酸为对照品,采用5%香草醛冰醋酸溶液、高氯酸显色后,进行山楂药材及提取物总三萜酸的含量测定.考察了显色剂香草醛、高氯酸用量,水浴温度等.结果:5%香草醛-冰醋酸溶液0.4 mL,高氯酸1.0 mL,60℃水浴15 min,冰浴冷却,加冰醋酸5.0 mL摇匀,在548 nm处测定,其效果最佳.标准曲线方程y=0.006 178x 0.005 600(r=0.999 8),药材的平均回收率为97.22%,RSD为1.32%;总三萜酸提取物的平均回收率为100.6%,RSD为0.82%.结论:该比色法操作简便,吸收值稳定,并且干扰小.     

Monoterpene and lignan glycosides in the leaves of Crataegus pinnatifida

In the present phytochemical study on the leaves of Crataegus pinnatifida, a new monoterpene glycoside, (3S,5R,6R,7E,9R)-3,6-epoxy-7-megastigmen-5,9-diol-9-O-β-Dglucopyranoside(6) and a new sesquilignan glycoside, acernikol-4’’-O-β-D-glucopyranoside (15), together with thirteen known compounds were isolated.     

Phenolic compounds from the leaves of Cornus controversa

Two novel phenolic compounds from the leaves of Cornus controversa (Cornaceae) were characterized as (-)-2,3-digalloyl-4-(E)-caffeoyl-L-threonic acid and (-)-2-galloyl-4-(E)-caffeoyl-L-threonic acid, using spectroscopic methods.     

Four new compounds from the leaves of Acer truncatum

Four new compounds, 3-(4-hydroxy-3,5-dimethoxyphenyl)propyl formate (1), 2,6-dimethoxy-4-[(1S)-3-methoxypropyl]phenol (2), (1R,2R)-4-[(3R)-3-hydroxybutyl]-3,3,5-trimethylcyclohex-4-ene-1,2-diol (3), and (1S,3R,3aR,6S,7S,9aR)-decahydro-1-(hydroxymethyl)-1,7-dimethyl-3a,7-methano-3aH-cyclopentacyclooctene (4) were isolated from the leaves of Acer truncatum, together with twelve known compounds. Their structures were elucidated on the basis of extensive spectroscopic techniques. The absolute configuration of compound 3 was established by the modified Mosher's method. All compounds were evaluated for antibacterial activities.     

Phenolic compounds from Forsythia leaves

Four lignans, four lignan glucosides, one flavonoid and two caffeoyl glycosides of 3,4-dihydroxyphenethyl alcohol were identified variously in leaves of Forsythia suspensa, F. viridissima and F. koreana. The leaf patterns were broadly similar to those reported earlier for the fruits, except that suspensaside and β-hydroxyacteoside were not detected.     

Monoterpene and pregnane glucosides from Solenostemma argel

From the aerial parts of Solenostemma argel, two monoterpene glucosides have been isolated and identified as 6,7-dihydroxy-dihydrolinalool 3-O-beta-glucopyranoside and 6,7-dihydroxy-dihydrolinalool 7-O-beta-glucopyranoside. A pregnane glucoside was also isolated and assigned as pregn-5-ene-3,14-beta-dihydroxy-7,20-dione 3-O-beta-glucopyranoside together with the known compounds benzyl alcohol O-beta-apiofuranosyl-(1-->6)-beta-glucopyranoside, 2-phenylethyl O-alpha-arabinopyranosyl-(1-->6)-beta-glucopyranoside, astragalin and kaempferol-3-O-alpha-rhamnopyranosyl-(1-->2)-beta-glucopyranoside.     

A prenylated xanthone and antiproliferative compounds from leaves of Pentadesma butyracea

A new prenylated xanthone, butyraxanthone F (1) together with 20 known compounds were isolated from the leaves of Pentadesma butyracea. Their identification was achieved by spectroscopic means and comparison of the data with literature or by direct comparison on TLC with authentic samples. To the best of our knowledge, this is the first report of 2-hydroxy-2,3-dihydrosqualene (17) from a natural source. Compounds 2–6 and 11–16 were found for the first time in this genus. The antiproliferative activity of the crude extract, fractions and some isolated compounds was evaluated against three human cancer cell lines, BGC-823, Hela and A549. The crude extract, fractions B and C showed weak activities. Globuxanthone (2) and 30-epi-cambogin (7) were found to be the most active compounds on the three cancer cells. The effect of 2 on Hela cells and that of 7 on BGC-823 cells were noteworthy. The antiproliferative potential of allanxanthone A (3), ergosta-4,6,8(14),22-tetraen-3-one (14) and 2-hydroxy-2,3-dihydrosqualene (17) against BGC-823 and Hela cells could be classified as moderate-to-weak.     

羽叶鬼灯檠中的单萜二糖苷

从羽叶鬼灯檠 (RodgersiapinnataFranch .)的根茎中分离得到 6个单萜二糖苷 ,它们的结构通过波谱方法分别鉴定为 :(E ) 3,7 dimethyl 1 O [α L rhamnopyranosyl (1→ 6 ) β D glu copyranosyl] oct 2 en 7 ol (1) ,(E ) 3,7 dimethyl 1 O [α L arabinofuranosyl (1→ 6 ) β D glucopy ranosyl] oct 2 en 7 ol (2 ) ,geranyl 1 O α L arabinofuranosyl (1→ 6 ) β D glucopyranoside (3) ,gera nyl 1 O α L rhamnopyranosyl (1→ 6 ) β D glucopyranoside (4 ) ,geranyl 1 O β D xylopyranosyl (1→6 ) β D glucopyranoside (5 ) ,geranyl 1 O α L arabinopyranosyl (1→ 6 ) β D glucopyranoside (6 )。其中化合物 1为新化合物 ,单萜二糖苷类化合物系首次在该属中发现。     

Accumulation and degradation of organotin compounds in cultivated sporophytes of the brown alga Undaria pinnatifida

Journal of Applied Phycology - Seaweeds could play a significant role in alleviating coastal chemical pollution through accumulation and degradation. In the present study, the accumulation and...     

Cultivated hawthorn (Crataegus pinnatifida var. major) genome sheds light on the evolution of Maleae (apple tribe)

Cultivated hawthorn (Crataegus pinnatifida var. major) is an important medicinal and edible plant with a long history of use for health protection in China. Herein, we provide a de novo chromosome-level genome sequence of the hawthorn cultivar “Qiu Jinxing.” We assembled an 823.41 Mb genome encoding 40 571 genes and further anchored the 779.24 Mb sequence into 17 pseudo-chromosomes, which account for 94.64% of the assembled genome. Phylogenomic analyses revealed that cultivated hawthorn diverged from other species within the Maleae (apple tribe) at approximately 35.4 Mya. Notably, genes involved in the flavonoid and triterpenoid biosynthetic pathways have been significantly amplified in the hawthorn genome. In addition, our results indicated that the Maleae share a unique ancient tetraploidization event; however, no recent independent whole-genome duplication event was specifically detected in hawthorn. The amplification of non-specific long terminal repeat retrotransposons contributed the most to the expansion of the hawthorn genome. Furthermore, we identified two paleo-sub-genomes in extant species of Maleae and found that these two sub-genomes showed different rearrangement mechanisms. We also reconstructed the ancestral chromosomes of Rosaceae and discussed two possible paleo-polyploid origin patterns (autopolyploidization or allopolyploidization) of Maleae. Overall, our study provides an improved context for understanding the evolution of Maleae species, and this new high-quality reference genome provides a useful resource for the horticultural improvement of hawthorn.