Characterization of antioxidant and antibacterial compounds from aerial parts of Haplophyllum tuberculatum

The aerial parts of Haplophyllum tuberculatum(H.tuberculatum)have traditionally been used by local communities to treat fever,gastrointestinal disorders,worms,malaria and fractures,how-ever,the responsible ingredients of the selected medicinal plant have not been identified.In the present study,antibacterial and antioxidant ingredients were isolated and characterized from the plant parts of locally grown H.tuberculatum,and their biological activity was evaluated.The powder aerial parts were extracted with methanol and the extract was successively frac-tionated with different polarities of solvents.All polarities of extracts(hexane,chloroform,ethyl acetate,butanol,methanol and water)were used to determine their antibacterial and antioxi-dant activity by established in-vitro method.The disk diffusion and free radical scavenging 2,2-diphenyl-1-picrylhydrazyl(DPPH)methods were used to evaluate antibacterial and antioxidant activities of the prepared extracts and pure isolated compounds at different concentrations against three strains of Gram-positive and three Gram-negative bacteria.The antibacterial activity results showed that all prepared fractions and isolated pure compounds of the plant species gave signif-icant activity against all Gram(+and-)bacterial strains with the range of inhibition 0-20 mm.The antioxidant activity of the prepared extracts at all concentrations also showed substantial activity.Based on the highest activity,ethyl acetate and chloroform extracts were selected for the separation and isolation of antioxidant and antibacterial compounds by thin layer chromatogra-phy(TLC),column chromatography(CC),and preparative thin layer chromatography(PTLIC).The structure of the isolated antioxidant and antibacterial compounds from the ethyl acetate and chloroform extracts were determined on the basis of nuclear magnetic resonance(NMR)and mass spectra.The isolated pure compounds and active extracts could be used as a medicine for various infectious related diseases.

Evaluation of antioxidant potential,total phenolic content and phytochemical screening of aerial parts of a folkloric medicine,Haplophyllum tuberculatum(Forssk)A.Juss

Objective:To quantify total phenols,flavonoids and to investigate the in vitro antioxidant power of Haplophyllum tuberculatum(H.tuberculatum)leaves extracts of varying polarities.Methods:The authenticated sample of H.tuberculatum(50 g)leaves was dried under shade,powdered and extracted exhaustively with ethanol by cold percolation method.The alcoholic extract was further partitioned into petroleum ether,acetone,chloroform and methanol to obtain the fractions of varying polarities which were subjected to qualitative phytochemical testing.Total phenolics and flavonoids content in the acetone,chloroform and methanol extracts were quantified by using standard colorimetric methods.Petroleum ether extract was omitted because it did not show the presence of either tannins or flavonoids.In vitro antioxidant activity and total antioxidant capacity were determined by using 1,1 diphenyl-2-picrylhydrazyl radical and phosphomolybdenum reagent.Ascorbic acid was used as a reference antioxidant for comparison purpose.Results:Qualitative phytochemical results of leaves extracts confirmed the presence of major secondary plant metabolites.The extraction of phenolic compounds varied considerably according to the polarity of solvent.The most polar fractions i.e.methanol were observed to have the highest phenolic content(561.22 mg/g of gallic acid equivalent)and flavonoids(165.54 mg/g of quercetin equivalent).Although the free radical scavenging activity of leaves fractions was noted to be slightly lower than the reference compound,a direct relationship was observed between phenolic content and in vitro antioxidant activity.On the other hand,leaves fractions exhibited significant total antioxidant capacity as ascorbic acid equivalent.Conclusions:The aerial part of H.tuberculatum is rich in phenolic compounds which might play a vital role in the discovery of natural antioxidants.

轮纹异痂蝗卵的过冷却能力与其体内水分和生化物质含量的关系

【目的】低温是影响昆虫生长发育和存活的关键因子之一。为明确轮纹异痂蝗Bryodemella tuberculatum dilutum卵的抗寒性及其机理,研究了其过冷却能力与其体内水分及其他抗寒性相关生化物质含量的关系。【方法】采用热电偶法测定了轮纹异痂蝗卵的过冷却点,同时采用烘干法、残余法、氨基酸自动分析仪和高效液相色谱法分别测定了其卵的含水量、脂肪、氨基酸及小分子糖醇的含量。【结果】土壤含水量对轮纹异痂蝗滞育前卵的含水量、脂肪含量(鲜重)及过冷却点有极显著的影响(P<0.01)。随着土壤含水量从4%增加到13%,卵含水量从45.12%上升到55.25%,卵脂肪含量(鲜重)从10.39%下降到9.39%,而过冷却点从-30.11℃上升到-25.69℃。不同发育阶段卵的过冷却点、含水量、脂肪、氨基酸及小分子糖醇含量存在极显著差异(P<0.01)。从卵产下当天至120 d,卵过冷却点从-26.78℃下降至-30.18℃,含水量从51.93%下降至46.69%,脂肪含量分别从9.99%(鲜重)和17.37%(干重)上升至13.92%(鲜重)和25.29%(干重)。滞育卵的过冷却点显著低于滞育前卵的过冷却点。从卵中共检测到17种氨基酸,其中5种与过冷却点存在显著的相关关系(P<0.05)。卵过冷却点随着甘氨酸和脯氨酸含量的升高而降低,而随着胱氨酸、亮氨酸及天冬氨酸含量的增加而升高。随着卵的发育,海藻糖、甘油、肌醇和山梨醇含量逐渐上升,而葡萄糖和果糖含量逐渐下降。在卵发育过程中,海藻糖和甘油的含量显著高于其他4种物质的含量。卵过冷却点与上述6种小分子糖醇均存在显著的相关关系,其中与海藻糖和葡萄糖的相关性最强。过冷却点随海藻糖、甘油、肌醇和山梨醇含量的升高而降低,而随葡萄糖和果糖含量的升高而上升。【结论】轮纹异痂蝗卵在发育过程中,通过降低含水量,积累脂肪、脯氨酸、甘氨酸及海藻糖、甘油、肌醇和山梨醇等抗寒物质,从而提高其过冷却能力。

轮纹异痂蝗消化道和马氏管组织学观察

利用石蜡切片及HE染色法对轮纹异痂蝗Bryodemella tuberculatum dilutum(Stoll)消化道和马氏管的组织学结构进行研究。结果表明,轮纹异痂蝗的消化道前肠结构由内向外分为内膜、肠壁细胞层、基膜、纵肌、环肌和围膜6层,中肠由内向外分为围食膜、肠壁细胞层、基膜、环肌、纵肌和围膜6层,中肠与前肠的组织结构有显著的差异。后肠的结构与前肠基本相似,但内膜比前肠薄且肌肉排列不规则。马氏管着生在中肠和后肠的交界处,其显微结构由内向外为绒毛膜、上皮层和薄膜。轮纹异痂蝗消化道前肠、中肠及后肠结构有差异,这样的差异与其功能有着密切的联系。

轮纹异痂蝗触角感器的扫描电镜观察

利用扫描电镜观察了轮纹异痂蝗[Bryodemella tuberculatum dilutum(Stoll)]成虫触角感器的类型和分布。结果表明:轮纹异痂蝗触角为丝状,由柄节、梗节和鞭节组成,雄性个体鞭节包括24个亚节,雌性个体鞭节包括23个亚节。雌雄个体均具有12种感受器,即毛形感受器、刺形感受器(Ⅰ型和Ⅱ型)、锥形感受器(Ⅰ型、Ⅱ型、Ⅲ型、Ⅳ型和Ⅴ型)、腔锥形感受器、腔形感受器及Bhm氏鬃毛。根据各类感器的形态、分布和显微结构探讨了其可能承担的功能。

瘤果三宝木枝叶的酚类成分研究

目的:研究瘤果三宝木枝叶的化学成分。方法:利用反相硅胶柱色谱和反相制备液相色谱等手段进行分离纯化,并通过~1H-NMR、^(13)C-NMR等波谱技术进行结构鉴定。结果:从瘤果三宝木枝叶95%乙醇提取物分离得到12个化合物,分别鉴定为:汉黄芩素(1)、8-甲氧基异黄芩素(2)、异嗪皮啶(3)、5,8,2′-三羟基-6,7-甲氧基黄酮(4)、黄芩素(5)、黄芩新素Ⅱ(6)、千层纸素-A(7)、东莨菪素(8)、3,4,5-三甲氧基苯酚(9)、香草醛(10)、2(S)-5,7-二羟基-6-甲氧基二氢黄酮(11)、isoscutellarein(12)。结论:所有化合物均为首次从该植物中分离得到。

曲霉及其有性型散囊菌的新分类群和新记录种

在收集和分离我国曲霉工作中,发现一个国内新纪录和三个新分类群:1.埃及曲霉,国内新记录。2.合阳曲霉新种,与爪甲曲霉相近,但颜色和具刺不育菌丝有所不同。3.温特曲霉烟色变种,与原变种的主要区别在于颜色为蓝灰色并具异常膨大的梗基。4.瘤突散囊菌新种,其子囊孢子的纹饰独特,凸面具粗疏瘤状突起。