Study of dynamic accumulation of secondary metabolites in three subspecies of Hypericum perforatum

St. John's Wort extracts are used for the treatment of mild to moderately severe depression, and their composition and standardization have been thoroughly investigated. Standardization of St. John's Wort extracts has to cope with several factors that affect the phytochemical profile of the plant, with geographic location, seasonal variations and subspecies all being important. To address this issue, three different subspecies of Hypericum perforatum L. were profiled in relation to different maturation phases, evaluating the variations in the context of the major secondary metabolites from this plant. HPLC analysis indicated that H. perforatum subsp. perforatum is richer in secondary metabolites than the other subspecies, and that the three subspecies show a different profile during the developmental stages. Hypericins, hyperforins and flavonoids peak at quite different stages, and the standardization of Hyperici extracts based only on the contents of hypericin is not adequate to guarantee batch reproducibility of the extracts.     

乌腺金丝桃茎尖离体培养基激素配比筛选

为寻求乌腺金丝桃的高效人工繁殖方法,以乌腺金丝桃茎尖作为外植体,筛选初代诱导、继代增殖、生根培养3个阶段的最佳培养基激素配方。结果得出,把经过消毒后的乌腺金丝桃茎尖切割成0.3 mm、周围带2~3个叶原基,转入MS+6-BA 3.0 mg/L+NAA 0.1 mg/L+LH 500 mg/L培养基,分化率达到100%,能诱导出大量的健壮不定芽;然后将这些不定芽切割成1 cm小段转入MS+6-BA 2.0 mg/L+IBA 0.2 mg/L+GA_3 1.0 mg/L培养基,增殖效果最好;经过2~3次的继代增殖后,将增殖的大量苗木切割成2 cm小段转入到1/2 MS+IAA 0.2 mg/L生根培养基中,生根效果最佳,平均根数达到4.6,且根系粗壮,有利于今后出瓶移栽。     

贯叶金丝桃的电子束辐照杀菌研究

研究电子束辐照贯叶金丝桃杀菌的可行性,为科研和生产中有效地应用该方法提供理论依据。辐照样品中微生物数量的测定依据《中华人民共和国药典》提供的方法;应用高效液相色谱检测有效成分金丝桃素和金丝桃苷含量;依据微生物存活对数与辐照剂量的线性关系,求得D10;采用目测、鼻嗅、品尝的评定方法,评定样品辐照前后的外部性状变化。结果表明:细菌、霉菌+酵母菌的D10值分别为2.91 kGy和4.69 kGy,霉菌和酵母菌相对于细菌对电子束有更强的耐受力,适宜的辐照加工剂量为4.5~6.5 kGy,经过辐照后,样品可以保存30~150 d,卫生指标仍达到国家药典中规定的中药粉剂微生物限度标准,金丝桃苷和金丝桃素的含量未发生显著变化。因此,利用电子束辐照贯叶金丝桃杀菌是一种行之有效的方法。     

乌腺金丝桃显微特征观察

为了探讨乌腺金丝桃(Hypericum attenuatum Choisy)的显微特征,采用显微鉴定方法对乌腺金丝桃茎、叶横切面及全草粉末进行生药学研究。结果表明,乌腺金丝桃茎横切面维管束为外韧型;叶为异面叶,栅栏细胞一列;全草粉末石细胞众多;导管为螺纹、具缘纹孔,少为网纹;花粉粒长球形;气孔为不定式或不等式。     

长柱金丝桃(Hypericum ascyron L.)分泌结构的研究

对长柱金丝桃各类器官进行了整体透明和解剖学研究,确定合理的采收部位和采摘时间。结果表明,植株富含分泌囊和分泌小管道两种分泌结构;叶片中分泌囊(道)的发育属于裂生型;地上部分泌结构分布较多,尤以叶片中数量最多、分布密度最大;确定植物的最佳采收时期是每年8～9月的花果期、最佳采收部位是地上部。此研究结果为此药用植物合理的采收部位和采收时间的确定提供解剖学依据,同时为其他植物分泌囊(道)发育规律的研究提供理论依据。     

Essential oil composition of Hypericum perfoliatum L. and Hypericum tomentosum L. growing wild in Tunisia

The essential oils obtained by hydrodistillation from the aerial parts of Tunisian native Hypericum perfoliatum L. (sect. Drosocarpium Spach.) and Hypericum tomentosum (sect. Adenosepalum Spach.) were analyzed by GC and GC–MS. Thirty-two compounds were identified in the essential oils of H. perfoliatum with α-pinene (13.1%), allo-aromadendrene (11.4%), germacrene-D (10.6%), n-octane (7.3%), α-selinene (6.5%) and β-selinene (5.5%) as main constituents. Sixty-seven components were identified in the oil of H. tomentosum with menthone (17.0%), n-octane (9.9%), β-caryophyllene (5.3%), α-pinene (5.2%), lauric acid (4.1%) and β-pinene (3.7%) as the most abundant components. Both oils were characterized by the presence of many components which could have numerous applications in food, pharmaceutical and perfume industries.     

Induction of hypericins and hyperforin in Hypericum perforatum L. in response to biotic and chemical elicitors

Hypericum perforatum L. produces hyperforins, a family of antimicrobial acylphloroglucinols; and hypericins, a family of phototoxic anthraquinones exhibiting anti-microbial, anti-viral, and anti-herbivore properties in vitro. To determine whether these secondary metabolites are part of the specific plant defense systems that are mediated by methyl jasmonate or salicylic acid, we used meristem cultures to assess the effects of exposure to exogenous application of these chemical elicitors. Levels of hypericins in plant tissue increased in response to both elicitor treatments; total hypericin levels increased as much as 3.3 times control levels when treated with 200 μ methyl jasmonate for 14 days. Increased hyperforin concentrations were detected when plantlets were treated with 1 m salicylic acid or 50 μ methyl jasmonate. For assessing responses to a biotic elicitor, greenhouse-grown plant materials were inoculated with the plant pathogen, Colletotrichum gloeosporioides. Levels of hypericins increased twice as much as the control when inoculated with 1 × 10⁴ spores per ml; higher doses of spores overwhelmed the plant defenses. The elevation of hypericins and hyperforin in response to chemical and biotic elicitors suggests that these secondary metabolites are components in the inducible plant defense responses of H. perforatum.     

西南金丝梅中结构新颖的PPAPs类化合物

以西南金丝梅(Hypericum henryi Levl.et fan)地上部分为材料,将其正己烷组分通过硅胶柱层析、中压制备色谱(MPLC)、SephadexLH-20凝胶柱层析等方法,分离并得到4个化合物,包括2个内酯环的间苯三酚类化合物(PPAPs),1个单环体系的间苯三酚类化合物(MPAPs)和1个双环体系的间苯三酚类化合物(BPAPs),其中1个为新的PPAPs类化合物,将其命名为hyphenrone Y。所有化合物的结构均通过核磁共振和质谱等多种波谱技术进行确定。     

Agronomic and chemical characterization of 39 Hypericum perforatum accessions between 1998 and 2000

Thirty‐nine accessions of St John's Wort were studied over a 3‐year period. The percentage of diseased plants ranged from 0 to 100%. After 3 years of cultivation, 18% of the accessions presented a dieback rate of <10%. Hypericins and hyperforins in flowering tops (top 30 cm of plants at full bloom) and flowers were assayed using high‐performance liquid chromatography (HPLC‐DAD Diode Array Detector) (one to three cuttings a year). The hypericin contents in flowering tops ranged from 0.7 to 3%. These levels were, on average, 2.8‐fold lower than those recorded in flowers. Hyperforin levels varied in the different accessions, ranging from 0.65 to 3% in flowering tops and 2 to 5.7% in the flowers. In line with present industrial needs, a minimum content of one or more of the active components, it will therefore be necessary to select accessions in terms of the dry weight yield and the contents of flowering tops and flowers. Dry weight depends on cutting height, which also affects the quality of the plant material harvested. Because of the plant to plant variability, the performance of the accessions selected would be improved.     

不同生长调节剂对金丝梅组培快繁的影响

本研究以云南野生金丝梅(Hypericum patulum)带休眠芽的茎段为外植体,研究了不同植物生长调节剂对其离体培养的影响,以建立金丝梅离体快繁技术体系。研究结果表明,腋芽诱导的适宜培养基为MS+6-BA 2.0 mg/L+NAA 0.1 mg/L,诱导率可达90%;适合腋芽增殖的培养基为MS+6-BA 1.0 mg/L+NAA 0.1 mg/L+GA30.1 mg/L,增殖系数可达5.12;最佳生根培养基为1/2MS+IBA 0.5 mg/L+活性炭0.1 g/L,生根率为96.69%。炼苗移栽到草炭土∶珍珠岩=2∶1的基质中,成活率达100%,移栽到苗圃后成活率为100%。研究结果为金丝梅高效快速繁殖以及优良品种选育提供科学依据。