酸浆的化学成分及药理作用研究进展

酸浆为茄科多年生草本植物,资源丰富,应用广泛。迄今已从酸浆中分离鉴定出159种化合物,可分为类固醇类、黄酮类、苯丙素类、含氮化合物等。借助现代药理学研究手段,酸浆广泛的药理活性被陆续发现,其可发挥抗炎、抗菌、抗氧化、抗肿瘤等功效,同时在抗糖尿病、抗衰老、抗肥胖以及调节肠道菌群平衡等方面也发挥着重要的作用。本文主要对酸浆化学成分及药理作用的研究进展进行综述,以期为酸浆的合理开发和综合应用提供科学依据。     

Effect of Heliothis subflexa herbivory on fruit abscission by Physalis species: the roles of mechanical damage and chemical factors

1. Insect oral secretions are important for the induction of a number of plant responses, but the relative role of mechanical damage in the induction of these responses is often not well understood. Damage from the frugivore Heliothis subflexa, a specialist on Physalis species, causes herbivore‐induced fruit abscission. In this field study, we examined the separate and combined effects of mechanical damage and H. subflexa oral secretions on Physalis fruit abscission. 2. To determine the relative role of mechanical and chemical factors, the following treatments were administered to fruit: (1) three levels of mechanical damage, (2) natural herbivore damage by control larvae and by larvae surgically treated to inhibit saliva secretion, and (3) injection of H.subflexa oral secretions and a water control. Abscission of mechanically damaged fruit with and without the addition of oral secretions was also compared. 3. Mechanical damage was sufficient to cause fruit abscission, and the addition of oral secretions to mechanically damaged fruit did not cause an increase in fruit abscission. Normal caterpillars and those treated to inhibit saliva secretion caused similar abscission rates. 4. Though most studies examining the effects of insect oral secretions on induced plant responses find these chemical stimuli to be important or essential, the results of the present study showed that oral secretions are not necessary for fruit abscission. Future work is needed to determine the relative importance of mechanical damage in herbivore‐induced plant responses in other systems.     

Physalin B inhibits Rhodnius prolixus hemocyte phagocytosis and microaggregation by the activation of endogenous PAF-acetyl hydrolase activities

The effects of physalin B (a natural secosteroidal chemical from Physalis angulata, Solanaceae) on phagocytosis and microaggregation by hemocytes of 5th-instar larvae of Rhodnius prolixus were investigated. In this insect, hemocyte phagocytosis and microaggregation are known to be induced by the platelet-activating factor (PAF) or arachidonic acid (AA) and regulated by phospholipase A₂ (PLA₂) and PAF-acetyl hydrolase (PAF-AH) activities. Phagocytic activity and formation of hemocyte microaggregates by Rhodnius hemocytes were strongly blocked by oral treatment of this insect with physalin B (1 μg/mL of blood meal). The inhibition induced by physalin B was reversed for both phagocytosis and microaggregation by exogenous arachidonic acid (10 μg/insect) or PAF (1 μg/insect) applied by hemocelic injection. Following treatment with physalin B there were no significant alterations in PLA₂ activities, but a significant enhancement of PAF-AH was observed. These results show that physalin B inhibits hemocytic activity by depressing insect PAF analogous (iPAF) levels in hemolymph and confirm the role of PAF-AH in the cellular immune reactions in R. prolixus.     

Agrobacterium-mediated transformation of tomatillo (Physalis ixocarpa) and tissue specific and developmental expression of the CaMV 35S promoter in transgenic tomatillo plants

A protocol for the Agrobacterium-mediated transformation of tomatillo was developed. Up to 40 transgenic plants could be obtained in experiments using 60 cotyledon expiants. The transformed nature of the regenerated plants was confirmed by NPT II and Southern blot hybridization analysis. Using the b-glucuronidase system the tissue specific and developmental patterns of expression of the Cauliflower Mosaic Virus 35S promoter were determined in transgenic tomatillo plants. It was found that this promoter is developmentally regulated during fruit and seed formation.     

Immune depression in Rhodnius prolixus by seco-steroids, physalins

A comparative study of the effects of physalins, seco-steroidal substances of Physalis angulata (Solanaceae), on the immune reactions of R. prolixus was carried out. Ecdysis and mortality were not affected by treatment with physalins B, D, F or G (1-10 microg/ml of blood meal). R. prolixus larvae fed with blood containing physalins and inoculated with 1 microl of Enterobacter cloacae beta12 (5 x 10(3)/insect) exhibited mortality rates three times higher than controls. The insects treated with physalin B, and F (1 microg/ml) and inoculated with E. cloacae beta12 showed significant differences on lysozyme activity in the hemolymph compared to untreated insects. Furthermore, physalin D (1 microg/ml) significantly reduced the antibacterial activity. Concerning cellular immune reactions, all insects treated with physalins (1 microg/ml), exhibited drastic reductions in the quantity of yeast cell-hemocyte binding and subsequent internalization. Insects inoculated with bacteria and treated with physalins B, F and G showed reductions of microaggregate formation but physalin D did not. Physalins B and F also reduced total hemocyte count in the hemolymph. These results suggest that, in different ways, probably due to their different chemical structures, physalin B, D, F and G are immunomodulatory substances for the bloodsucking insect, R. prolixus.     

ABA诱导毛酸浆下胚轴体细胞胚状结构的直接发生

研究了ABA与2,4-D等植物激素对毛酸浆组织培养的影响。其中,以浓度为1.0mg/L的2,4-D对毛酸浆下胚轴愈伤组织诱导结果最好。在子叶、子叶柄、下胚轴以及胚根四者当中,下胚轴对2,4-D的反应状况最好。结合ABA与2,4-D在MS培养基上能够有效地诱导出高质量的球形胚状结构。经过4周的培养,在2.0mg/L2,4-D和1.0mg/L ABA组合的情况下,球形胚状结构的诱导频率可达96.7％,每块外植体平均能产生6.7个球形胚状结构。球形胚状结构可以至少在5代以内反复发生。进一步讨论了ABA对毛酸浆体细胞胚发生的影响以及体细胞胚发生与环境胁迫的可能关系。     

Cytotoxic withanolides from Physalis angulata L

Four new withanolides, physagulins L-O (1-4), were isolated from the MeOH extract of the aerial parts of Physalis angulata L. (Solanaceae), together with seven known withanolides, compounds 5-11. Their structures were determined by spectroscopic techniques, including 1H-, 13C-NMR (DEPT), and 2D-NMR (HMBC, HMQC, 1H,1H-COSY, NOESY) experiments, as well as by HR-MS. All eleven compounds were tested for their antiproliferative activities towards human colorectal-carcinoma (HCT-116) and human non-small-cell lung-cancer (NCI-H460) cells. Compound 5 exhibited the highest anticancer activity against the HCT-116 cell line, with an IC50 value of 1.64+/-0.06 microM. Compound 9 exhibited the highest cytotoxicity towards the NCI-H460 cell line, with an IC50 value of 0.43+/-0.02 microM.     

Trypanosoma rangeli: effects of physalin B on the immune reactions of the infected larvae of Rhodnius prolixus

Physalins are seco-steroids obtained from plants of the family Solanaceae. Herein, we tested Physalis angulata L purified physalin B as an immunomodulatory compound in 5th-instar larvae of Rhodnius prolixus, which were systemically infected with the H14 Trypanosoma rangeli strain protozoan. In uninfected insects, the effective concentration of physalin B, which inhibited 50% of the blood ingested (ED(50)) volume, was 15.2+/-1.6 microg/ml of the meal. Ecdysis processes and mortality in uninfected larvae, treated orally with physalin B in concentrations ranging from 1 to 10 microg/ml, was similar to that observed in insects not treated with physalin B. However, R. prolixus larvae previously fed on blood containing 1.0, 0.1, and 0.01 microg of physalin B/ml exhibited mortality rates of 78.1, 54.3, and 12.7%, respectively, 6 days after inoculation of T. rangeli (1 x 10(3) parasites/insect), whereas only 7.2% mortality was observed in the control group, injected with sterile culture medium. The insects treated with physalin B (0.1 microg/ml) and inoculated with T. rangeli did not modify the phenoloxidase (PO) activity and total hemocyte count in the hemolymph. However, physalin B treatment caused a reduction in hemocyte micro-aggregation and nitric oxide production and enhanced the parasitemia in the hemolymph. These results demonstrate that physalin B from P. angulata is a potent immunomodulatory substance for the bloodsucking insect, R. prolixus.     

13,14‐seco‐Withanolides from Physalis minima with Potential Anti‐inflammatory Activity

Four new 13,14‐seco‐withanolides, minisecolides A – D ( 1  –  4 ), together with three known analogues 5  –  7 , were isolated from the whole plants of Physalis minima. The structures of new compounds were determined on the basis of spectroscopic analysis, including ¹H‐, ¹³C‐NMR, 2D‐NMR (HMBC, HSQC, ROESY), and HR‐ESI‐MS. Evaluation of all isolates for their inhibitory effects on nitric oxide (NO) production was conducted on lipopolysaccaride‐activated RAW264.7 macrophages. Compounds 2 , 3 , 5 , and 6 showed inhibitory activities, especially for compound 5 with IC₅₀ value of 3.87 μm .     

Chromatographic analysis of carotenol fatty acid esters in Physalis alkekengi and Hippophae rhamnoides

The carotenol fatty acid esters of two potentially valuable sources of plant carotenoids, sepals of Physalis alkekengi (Chinese lantern) and fruits of Hippophae rhamnoides (sea buckthorn), were separated by column chromatography and identified by HPLC-DAD and HPLC-MS. A chemical and an enzymatic hydrolysis were employed to identify the parent carotenoids and to remove the lipid components. Zeaxanthin and beta-cryptoxanthin esters represented the main fraction in P. alkekengi sepals and an important one in H. rhamnoides fruits. Beta-Cryptoxanthin palmitate and zeaxanthin dipalmitate were identified as major compounds in both plants. In P. alkekengi, the carotenoids were mainly (> 90%) esterified with palmitic acid, and a high proportion (> 80%) of saturated medium chain fatty acids was found (by GC-MS) in the total lipid extract. Although the total lipid extract of H. rhamnoides contained significant amounts of unsaturated fatty acids, especially oleic and palmitoleic acids, the xanthophylls were mainly esterified with saturated fatty acids. The oleoresins of both species represent potential sources of carotenoid esters and can be used as food additives, cosmetic ingredients or nutraceuticals.