Phytochemical and chemotaxonomic study on Dictamnus angustifolius G. Don ex Sweet (Rutaceae)

A phytochemical investigation of Dictamnus angustifolius led to the isolation of 14 compounds, including six furoquinoline alkaloids (1–6), two sesquiterpenoids (7, 8) and six flavonoids (9–14). The structures of these compounds were identified by spectroscopic methods and a comparison of their data with those reported in the literature. This is the first report of three furoquinoline alkaloids 1–3 and six flavonoids 9–14 from the genus Dictamnus and the first isolation of compounds 4–8 from D. angustifolius. The chemotaxonomic significance of furoquinoline alkaloids and sesquiterpenoids has also been summarized.     

The effects of sex,age and diet of mice and gerbils on susceptibility to Microphallus pygmaeus (Digenea: Microphallidae)

Molan A. L. and James B. L. 1984. The effects of sex, age and diet of mice and gerbils on susceptibility to Microphallus pygmaeus (Digenea: Microphallidae). International Journal for Parasitology14: 521–526. Mature male mice (40–100-day-old) and gerbils (60–150-day-old) harbour significantly more Microphallus pygmaeus than their female counterparts. Adult worms from male mice and gerbils consistently contain more eggs than those from females but the differences are not significant. No sex differences in worm recovery occur in immature or ageing mice and gerbils. Seventy-day-old mice and gerbils of both sexes harbour significantly more worms with a higher egg production than immature and ageing animals. The worm burden of sucklings, however, is higher than in weanlings and mature mice and gerbils of both sexes fed on cow's milk harbour significantly more worms than those fed on a normal pellet diet.     

New-D-homoandrost-4,6-diene derivatives as potent progesterone receptor antagonist

The aim of this study was to synthesize three different D-homoandrostadiene derivatives (2–4) and study their biological activity. We carried out in vivo and in vitro experiments using female cycling mice, which were synchronized for estrus with luteinizing hormone-releasing hormone (LHRH) and injected with the steroidal compounds. It was also determined the binding of these compounds to the progesterone receptors (PR). Since these steroids have a new D-homoandrostandienone skeleton in their molecular structure, it was of interest also to study their binding to the androgen receptors (AR).After LHRH treatment, the mice of the control group showed the presence of 14 ± 4 corpus lutea in the ovary whereas the animals treated with steroids 2–4, with RBAs of 100%, exhibited 11 ± 7, 12 ± 2, and 10 ± 4 respectively. As a result of this study, it is evident that these steroids did not inhibit the ovulation in these animals.The uterus of the control group, showed the typical progestational activity with an enlarged endometrial thickness with a secretory activity. However, the endometrium of the mice treated with steroids 2–4 did not show an enlargement of the endometrium and no secretory activity could be detected. This fact indicates that compounds 2–4 had antagonistic activity in this tissue.The overall data show that steroids 2–4 are antagonists of the PR. However, they do not bind to the AR. These results also demonstrate that 2–4 have an antiprogestational activity in vivo, but do not decrease the number of corpus lutea in the ovary of mice treated with LHRH.     

Membrane defects of the tolerant B cell. I. Failure of antigen-induced capping.

In order to study the membrane function of tolerant B antigen-binding cells, tolerance to the trinitrophenyl (TNP) determinant was induced in mice by injecting the reactive form of the hapten, trinitrobenzene sulfonic acid (TNBS). By appropriate transfer experiments, Fidler and Golub (J. Immunol.112, 1891, 1974) had previously shown that this form of tolerance is a B-cell property, induced and expressed in the absence of T cells. Hapten inhibition demonstrated the TNP-specificity of receptors on TNP-donkey erythrocyte(TNP-D)-binding cells in tolerant and nontolerant mice. About 88% of these cells were B cells by immunofluorescence, and the remainder were T cells. In the tolerant mice, challenge with TNP-sheep erythrocytes failed to expand the TNP-binding population, but sheep erythrocyte binders and anti-sheep plaque-forming cells expanded normally. Despite little or no change in TNP-binding cell numbers after tolerance induction, the TNP-binding cells of tolerant animals could not cap their receptors, in contrast to the sheep erythrocyte-binding cells from the same animals which capped normally. Although there is no anti-TNP plaque-forming cell response when tolerogen and immunogen are given simultaneously, capping failure is not evident until 2–4 days after tolerogen exposure. By Day 7, substantial recovery of immune responsiveness had occurred, yet even 12 months after a single dose of tolerogen there was no restoration of capping. Thus despite the association of both capping failure and unresponsiveness with tolerogen exposure, these lymphocyte functional defects appeared not to be causally related.     

Delayed development of aggressive behavior in castrate isolated male mice

Male mice were castrated at 21–22 days of age. Intact and castrated mice were isolated to induce aggressive behavior. The incidence of fighting between paired nonisolated and isolated mice was measured at 3, 6, 12, and 23 weeks to determine the effect of time of isolation on aggressive behavior. After 3 weeks isolation, 90% of the intact isolated mice fought, but none of the castrate isolated mice fought. Aggressive behavior equivalent to that of intact isolated mice developed in the castrate mice after 23 weeks of isolation. These results suggest that the presence of gonadal androgen is important in expediting the onset of aggressive behavior in isolated mice, but its absence does not preclude its eventual development.     

Chemical constituents from the flower buds of Daphne genkwa (Thymelaeaceae)

Phytochemical investigation on the flower buds of Daphne genkwa led to the isolation of 22 compounds, including 17 daphne diterpenes (1–17), three tigliane types (18–20), and two diphenylpentanes (21–22). Compounds 19–21 were isolated from D. genkwa for the first time. These compounds were elucidated using spectroscopic methods and by comparing their data to those reported in the literature. On the basis of chemical research, the chemotaxonomic significance of the isolated compounds were discussed.     

Regio- and enantioselective bioreduction of methyleneketoesters using both polymeric resin and cellulose matrix

Methyleneketoesters were prepared in >90% yield by performing an IBX oxidation of Morita–Baylis–Hillman adducts. A methodology was developed to achieve methyl 3-aryl-3-keto-2-methylenepropanoate reduction using a screening of yeast strains in three different reaction procedures to obtain products with both high yield and diastereoselectivity. The reactions conducted in water provided inferior yields (50%) for substrates 2b–c. Employing Amberlite^® XAD7HP which was a substrate reservoir that also immediately extracted the products from the reaction medium after their formation, syn-4a–c and anti-4a–c were isolated in 60–70% yield, with high stereoselectivity (98–99% ee). The best results were obtained using substrates adsorbed on filter paper which provided products yields above 70%, a 99% ee and a diastereomoeric ratio (syn-4: anti-4) 9:1. Cellulose matrix has excellent potential to be successfully employed in general biocatalytic reactions.     

Echinococcus multilocularis: susceptibility and responses to infection in inbred mice

Kroeze W. K. and Tanner C. E. 1987. Echinococcus multilocularis: susceptibility and responses to infection in inbred mice. International Journal for Parasitology17: 873–883. Of six strains of mice examined, C57L/J mice were the most susceptible to intraperitoneal infections with Echinococcus multilocularis. Five of the six strains developed splenomegaly during the infection. Changes in leukocyte levels in infected mice were most pronounced in the C57L/J and BALB/cJ strains. Two of the six strains of mice, C57BL/6J and C57BL/6J (bg^J), showed low specific IgG responses to E. multilocularis when measured using an ELISA. Many of the responses observed were directly correlated with the parasite burden in infected animals. It is concluded that susceptibility or resistance to E. multilocularis in mice is probably controlled by non-H-2 gene(s); additionally, hematological and immunological responses to infection, although correlated to parasite burden, varied among strains of mice, suggesting some degree of host genetic control of these responses.     

Chemical constituents from Picrasma quassioides (D.Don) Benn. and their network analysis of chemotaxonomic significance

A phytochemical investigation of Picrasma quassioides (D.Don) Benn led to the isolation of seventeen compounds including five coumarins (1–5), six lignans (6–11), two alkaloids (12–13), two phenolic compounds (14–15), one megastigman glycoside (16) and one phenylpropanoid (17). The structures of those compounds were determined by spectroscopy data of NMR spectra. All of the compounds were isolated from P. quassioides for the first time. In this study, in order to discuss the chemotaxonomic significance of those compounds from P. quassioides, network analysis was carried out to determine the chemotaxonomic relationships among the Simaroubaceae family and the other families. The result showed that the Simaroubaceae family and the Rutaceae family, together with the Asteraceae family have some chemotaxonomic relationships.     

Chemical constituents from the roots and rhizomes of Silene tatarinowii Regel

Chemical investigation of the root and rhizome of Silene tatarinowii Regel led to the isolation of nine ecdysteroids (1–9) and one sterol (10). All the compounds were determined on the basis of MS and NMR and by comparison with those in the literature. All these compounds were isolated from S. tatarinowii for the first time. Furthermore, compounds 7–10 were isolated from Silene genus for the first time, of which compounds 7 and 8 were isolated from Caryophyllaceae family members for the first time. This is the first study to report the chemical constituents of S. tatarinowii and the chemotaxonomic relationships between Silene and other genera of Caryophyllaceae.     

SAR of a new antischistosomal urea carboxylic acid

Urea carboxylic acids, products of aryl hydantoin hydrolysis, were recently identified as a new antischistosomal chemotype. We now describe a baseline structure–activity relationship (SAR) for this compound series. With one exception, analogs of lead urea carboxylic acid 2 were quite polar with Log?D_7.4 values ranging from ?1.9 to 1.8, had high aqueous solubilities in the range of 25–100?µg/mL, and were metabolically stable. None of the compounds had measurable in vitro antischistosomal activity or cytotoxicity, but four of these had moderate worm burden reduction (WBR) values of 42–70% when they were administered as single 100?mg/kg oral doses to S. mansoni-infected mice. These data indicate that with the exception of the gem-dimethyl substructure and the distal nitrogen atom of the urea functional group, the rest of the structure of 2 is required for in vivo antischistosomal activity.     

Chemical constituents of sponge Pseudoceratina sp. and their chemotaxonomic significance

The chemical investigation of Pseudoceratina sp. led to the isolation of six compounds including tyrosine brominated isoxazoline alkaloids (1 and 2), polyketide (3), and 5α,8α-epidioxysterols (4–6). The structures of these compounds were identified by comparison of NMR and MS spectroscopic data with those previously reported. Compounds 3–6 were isolated for the first time from sponges of the genus Pseudoceratina. The chemotaxonomic significance of these compounds was discussed.     

Mechanisms of antibody formation: I. Early in vivo proliferation of mouse spleen T cells as an initial step in antibody formation

Spleen cultures prepared from mice injected 24 hr earlier with 2 × 10⁶?2 × 10⁸ sRBC and challenged in vitro with sRBC produced 10 times more anti-sRBC IgM PFC than cultures prepared from uninjected mice. The effect was specific for the particular species of foreign RBC injected in vivo. In vitro responses to TNP were also increased in spleen cultures prepared from animals injected 24 or 12 hr earlier with carrier RBC alone, directly implicating carrier-specific T cells in this process. Similar enhancements of PFC formation occurred in cultures prepared from mice which had been injected with sRBC 24 and 48 hr earlier, but which were exposed to lethal irradiation at 1 hr after injection of antigen, if their spleens were shielded extracorporeally during irradiation. This finding indicated that in vivo recruitment of antigen-reactive extrasplenic X-ray-sensitive cells from the circulating lymphocyte pool by the spleen could not account for the observed enhancement.Proliferation in the spleen of antigen-reactive T cells, commencing 12–20 hr after the administration of antigen, was demonstrated by the tritiated thymidine pulse technique. An 8-hr hot-pulse given to spleen cell cultures from normal animals at 20 hr after in vitro challenge with antigen did not affect the rate of generation of IgM-producing cells; however, administration of a similar pulse to cultures which were initiated at 12 or at 20 hr after the in vivo injection of sRBC eliminated the enhanced generation of PFC and delayed the in vitro response to sRBC by 24 hr.Spleen cell cultures were prepared from mice which had been injected in vivo with sRBC at 12, 20, and 70 hr earlier, and 8- to 10-hr hot pulses were given immediately after initiation of the cultures. The cultures were then challenged with sRBC-TNP; antibody responses to TNP were greatly reduced in hot-pulsed cultures prepared from mice injected in vivo with carrier RBC at 12 or 20 hr prior to initiation of the cultures. In contrast, antibody responses to TNP observed in hot-pulsed cultures prepared from mice which had been injected with carrier RBC at 70 hr prior to initiation of the cultures were generally similar to those of nonpulsed 70 hr control cultures. This result suggests that the onset of T helper cell proliferation begins within 12–20 hr after injection of antigen, but subsides in vivo within 70 hr. By that time, the antigen-reactive T cells have already differentiated to perform their helper function.In spite of the triggering of T-cell proliferation during the first 24 hr after injection of antigen, spleen cell cultures prepared from mice which had been injected 24 hr earlier in vivo with 2 × 10⁸ sRBC produced only minimal numbers of anti-sRBC PFC if no antigen was added to the cultures. The presence of unprocessed antigen thus appears to be a requirement for B-cell proliferation in vitro, even after T-cell division has been triggered. This finding is consistent with earlier suggestions that the function of “helper” T cells may not be limited to passive transport of antigenic determinants to B cells. Evidence is also presented to support the contention that the antigen-reactive T cell involved in this process may have to undergo cell division in order to develop “helper” capacity.     

Meroterpenoids from the fruiting bodies of higher fungus Ganoderma resinaceum

Phytochemical investigation on the fruiting bodies of Ganoderma resinaceum led to the isolation of five new meroterpenoids, namely ganoresinains A–E (1–5), and four known analogues (6–9). The new compounds were identified by extensive analyses of spectroscopic data (NMR, MS, UV, and IR) and comparison with the literature data. Compound 1 and 6 were isolated as enantiomeric mixture, which were separated over analytical chiral HPLC chromatography. Compounds 6–9 were isolated from G. resinaceum for the first time.     

Sterols,aromatic compounds,and cerebrosides from the Hericium erinaceus fruiting body

Chemical investigation of the methanolic extract from the fruiting bodies of Hericium erinaceus, led to the isolation of fifty-one compounds including thirty-five ergostane-type sterols (1–35), fourteen aromatic compounds (36–49), and two cerebrosides (50 and 51). Their structures were identified based on spectroscopic analyses and by comparison of their spectral data with those reported in literature. This is the first comprehensive low-polarity chemical investigation of H. erinaceus. Thirty-one of the compounds (6–8, 11–35, 39, 41, and 49) were isolated for the first time from the genus Hericium and the family Hericiaceae. The chemotaxonomic relationship between H. erinaceus and other Hericium species was also discussed.     

Coumarins from the stems and leaves of Clausena dunniana H. Lév

Phytochemical study on the stems and leaves of Clausena dunniana H. Lév. led to the isolation and identification of 14 coumarins (1–14). Their chemical structures were determined on the basis of MS, NMR, and further supported by comparison with those reported in the literature. This is the first report that compounds 1–2, 4, 8, and 12–14 are present in the genus Clausena, and all of these compounds were isolated from C. dunniana for the first time. The chemotaxonomic significance of these isolated compounds was discussed.     

Presence of males affects the incidence of ovulation after pouch young removal in brushtail possums (Trichosurus vulpecula)

The traditional method for inducing and synchronising oestrus in the brushtail possum (Trichosurus vulpecula) is by removal of their suckling pouch young (RPY). However, our studies have recently shown that, in addition to wide variation between animals in the time of ovulation after RPY, a proportion of animals failed to ovulate. Evidence from several mammalian species indicates that the presence of males can stimulate ovarian activity and synchronise oestrus in females. The aim of this study was to determine the effect of the male on the oestrous cycle of the female brushtail possum after RPY. A total of 67 adult female brushtail possums were treated as three replicates. In order to observe the day of preovulatory follicle emergence and ovulation, animals underwent laparoscopic examination at 1–4 day intervals over a period from 0–21 days after RPY. The first replicate (N=18, May/June 1995) involved only animals kept in isolation from males, whereas the two remaining replicates compared ovarian responses between animals kept with (N=10, July 1995; N=14, June 1996) or in isolation from (N=10, July 1995; N=15, June 1996) males. The incidence of ovulation after RPY was significantly higher in females that were housed with males than in those kept in isolation from males (100%, 92.8% vs. 50.0%, 66.7%, 14.3%; P<0.001). Every animal that ovulated, had previously had a preovulatory follicle present at the site where the corpus luteum formed. Conversely, none of the animals that failed to ovulate, developed a preovulatory follicle during the period of study. The range of mean day of preovulatory follicle emergence (6.00–6.86 days), of ovulation (11.80–12.20 days) and the synchrony of ovulation between animals (range 8–17 days) after RPY, were not significantly affected by the presence of males. This study demonstrates for the first time, that the presence of males significantly increases the incidence of ovulation after RPY in the brushtail possum. However neither the timing of reproductive events nor the synchrony of ovulation were affected by presence of the male.     

New phenolic glycosides isolated from Penthorum chinense Pursh

A phytochemical investigation from 80% ethanol extract of Penthorum chinense Pursh (Saxifragaceae) resulted in the isolation of three new phenolic glycosides (1–3), together with three known phenolic glycosides (4–6). The structures of the new compounds were deduced from their comprehensive spectroscopic analysis including IR, HR-EI-MS, ¹H NMR, ¹³C NMR, DEPT, COSY, HMBC and HMQC. And the structures of known compounds 4–6 were identified by comparison of their spectral data with those reported in the literature.     

Chemical constituents from Cistanche sinensis (Orobanchaceae)

Phytochemical investigation of 70% aqueous EtOH extract of Cistanche sinensis led to the isolation of fifteen compounds (1–15), including nine phenylethanoid glycosides (PhGs, 1–9), five iridoid glycosides (10–14), and one lignan glycoside (15). Their structures were determined on the basis of 1D- and 2D-NMR experiments and by comparison with physical data of known compounds. Among the isolated compounds, 1 was identified as a new compound, three compounds (9, 14, and 15) were firstly reported from the genus Cistanche, and seven compounds (2–6, 11, and 12) were isolated from C. sinensis for the first time. PhGs with a 6′-O-rhamnosyl moiety such as cistansinenside B (1), poliumoside (7), and 2′-O-acetylpoliumoside (9) could serve as chemotaxonomic markers to differentiate C. sinensis from other species of Cistanche.     

Evaluation of single and joint effect of metabolites isolated from marine sponges,Fasciospongia cavernosa and Axinella donnani on antimicrobial properties

The biochemical mechanisms that marine sponges have developed as a chemical defense to protect themselves against micro and subsequent macrobiofouling process might comprise a potential alternative for the preventing attack of biofilm forming bacteria. The present study investigated the antimicrobial activity of a series of major secondary metabolites isolated from the sponges Fasciospongia cavernosa and Axinella donnani against fouling bacteria. Secomanoalide (1), dehydromanoalide (2) and cavernosine (3) have been isolated from F. cavernosa. Their structures were determined by MS, ¹H NMR spectra analyses and by comparison with those reported in the literature. The most promising activity was exhibited by the metabolites from A. donnani, that is, cerebroside (5) against three strains Aeromonas hydrophila subsp. salmonicida A449 and Erythrobacter litoralis. Our investigation revealed that combined metabolites 1, 2 and 3 retained strong activity but individual metabolite had moderate activity indicating that activity probably results from synergistic interactions between multiple compounds. The antibacterial screening of compounds 3, 5 and synergistic effect of 1–3 against fouling bacteria has been studied for the first time. Further, isolation of manoalide related compounds and their synergistic screening can be accelerated for the development of new biofilm inhibitors.