title: Indole diterpenoid secondary metabolites produced by the Epichloë festucae var. lolii – Lolium perenne symbiosis.

authors: Kaufononga, Sangata Ana Fiealu

abstract: The indole diterpenoid intermediates of lolitrems in a crude extract of Lolium perenne (L. perenne) seed infected with Epichloë festucae var. lolii (E. festucae var. lolii) and their biological activity against porina larvae were investigated.

Liquid-liquid partitioning of the crude extract, together with a series of bench columns (normal and reversed phase) and semi-preparative High Performance Liquid Chromatography (HPLC) yielded the novel compounds A – D (64 – 67).

Mass spectrometry (MS) and Nuclear Magnetic Resonance (NMR) spectroscopy were used to determine the structures of these alkaloids. The indole moiety of known indole diterpenoids was modified to a six-membered ring in the novel compounds A – D (64 – 67), with the right side of these molecules similar to that of lolitrem B (3) and terpendole C (49). Compounds A – D (64 – 67) differ in the stereochemistry and substituent at C-2. The structural features of these compounds are very unusual. These contain a spiro centre that fuses the modified indole region to the right side, indicating that they may be artefacts rather than naturally occurring, which in turn, could explain why they are not detectable in the Liquid Chromatography Mass Spectrometry (LC-MS) analysis of fresh extract. However, further work would be required to confirm this. 

The known alkaloids, terpendole D (50), 13-desoxypaxilline (37) and paspaline (42) were also isolated, together with a potential emindole analogue. This is the first report of terpendole D (50) from this ryegrass-endophyte association. The presence of an emindole analogue suggested that further intermediates are yet to be isolated from this association as indicated in the LC MS analysis of the crude extract. However, due to the scarcity of the emindole analogue, complete structural confirmation was not possible.

The biological activity of paxilline (36), lolitrem B (3), 13-desoxypaxilline (37), paspaline (42), terpendole D (50) and compounds A (64) and B (65) on porina larvae was determined using a semi-synthetic diet feeding bioassay. These compounds had not been previously tested on porina. Paxilline (36) had a dose-dependent effect on both food consumption and larval weight. Diet consumption and weight gain of porina larvae were significantly reduced by paxilline at concentrations of  2.5, 5 and 10 μg/g but not at concentrations of 1.0 μg/g, compared to dimethyl sulfoxide (DMSO) solvent control diet. Lolitrem B (3) had a similar effect on consumption and weight gain to that of paxilline (36) at concentrations of 5 and 10 μg/g but there was no indication that 13-desoxypaxilline (37), terpendole D (50), paspaline (42), compound A (64) or compound B (65) reduced feeding by porina larvae.

text: Indole diterpenoid secondary metabolites produced by the Epichloë festucae var. lolii – Lolium perenne symbiosis. The indole diterpenoid intermediates of lolitrems in a crude extract of Lolium perenne (L. perenne) seed infected with Epichloë festucae var. lolii (E. festucae var. lolii) and their biological activity against porina larvae were investigated.

Liquid-liquid partitioning of the crude extract, together with a series of bench columns (normal and reversed phase) and semi-preparative High Performance Liquid Chromatography (HPLC) yielded the novel compounds A – D (64 – 67).

Mass spectrometry (MS) and Nuclear Magnetic Resonance (NMR) spectroscopy were used to determine the structures of these alkaloids. The indole moiety of known indole diterpenoids was modified to a six-membered ring in the novel compounds A – D (64 – 67), with the right side of these molecules similar to that of lolitrem B (3) and terpendole C (49). Compounds A – D (64 – 67) differ in the stereochemistry and substituent at C-2. The structural features of these compounds are very unusual. These contain a spiro centre that fuses the modified indole region to the right side, indicating that they may be artefacts rather than naturally occurring, which in turn, could explain why they are not detectable in the Liquid Chromatography Mass Spectrometry (LC-MS) analysis of fresh extract. However, further work would be required to confirm this. 

The known alkaloids, terpendole D (50), 13-desoxypaxilline (37) and paspaline (42) were also isolated, together with a potential emindole analogue. This is the first report of terpendole D (50) from this ryegrass-endophyte association. The presence of an emindole analogue suggested that further intermediates are yet to be isolated from this association as indicated in the LC MS analysis of the crude extract. However, due to the scarcity of the emindole analogue, complete structural confirmation was not possible.

The biological activity of paxilline (36), lolitrem B (3), 13-desoxypaxilline (37), paspaline (42), terpendole D (50) and compounds A (64) and B (65) on porina larvae was determined using a semi-synthetic diet feeding bioassay. These compounds had not been previously tested on porina. Paxilline (36) had a dose-dependent effect on both food consumption and larval weight. Diet consumption and weight gain of porina larvae were significantly reduced by paxilline at concentrations of  2.5, 5 and 10 μg/g but not at concentrations of 1.0 μg/g, compared to dimethyl sulfoxide (DMSO) solvent control diet. Lolitrem B (3) had a similar effect on consumption and weight gain to that of paxilline (36) at concentrations of 5 and 10 μg/g but there was no indication that 13-desoxypaxilline (37), terpendole D (50), paspaline (42), compound A (64) or compound B (65) reduced feeding by porina larvae.

year: 2019

title: Lie theory and separation of variables. 6. The equation iUt + ∆2U = 0

authors: Boyer, C.P.

subjects: Mathematics

abstract: This paper constitutes a detailed study of the nine−parameter symmetry group of the time−dependent free particle Schrödinger equation in two space dimensions. It is shown that this equation separates in exactly 26 coordinate systems and that each system corresponds to an orbit consisting of a commuting pair of first− and second−order symmetry operators. The study yields a unified treatment of the (attractive and repulsive) harmonic oscillator, linear potential and free particle Hamiltonians in a time−dependent formalism. Use of representation theory for the symmetry group permits simple derivations of addition and expansion theorems relating various solutions of the Schrödinger equation, many of which are new.

text: Lie theory and separation of variables. 6. The equation iUt + ∆2U = 0 This paper constitutes a detailed study of the nine−parameter symmetry group of the time−dependent free particle Schrödinger equation in two space dimensions. It is shown that this equation separates in exactly 26 coordinate systems and that each system corresponds to an orbit consisting of a commuting pair of first− and second−order symmetry operators. The study yields a unified treatment of the (attractive and repulsive) harmonic oscillator, linear potential and free particle Hamiltonians in a time−dependent formalism. Use of representation theory for the symmetry group permits simple derivations of addition and expansion theorems relating various solutions of the Schrödinger equation, many of which are new.

year: 1975-03

title: Interface of gender and culture

authors: Tamasese, Kiwi

subjects: Maori

abstract: I greet you in the soothing waters of the Pacific. The birth waters of Hawai’i to the North, island of the dream time, and Aotearoa, to the south. Papua New Guinea to the West and Marquesas to the East.  These islands are the gathering places of the world’s largest Continent, the Pacific. We of this continent know that her birth waters are our connection.  We also know that she is woman identified. It is no surprise therefore that from Hawai’i to the north to Aotearoa in the south the positioning of women in each of these societies bears a different story to that of the women of the continent of Europe.  This reality lived out in Hawai’i means women shared with men the ultimate leadership of peoples.  This location of women power is named Kuhinanui. Many remarkable women of Hawai’i occupied this position.  From times of peace throughout to the first clash with imposed new culture, women of Hawai’i led, bled, struggled, defied and kept the kukui of self belief burning. Genealogically Hawai’i is connected to her other sisters throughout the Pacific.  The story of Kuhinanui Liliuokalani is poignant.

text: Interface of gender and culture I greet you in the soothing waters of the Pacific. The birth waters of Hawai’i to the North, island of the dream time, and Aotearoa, to the south. Papua New Guinea to the West and Marquesas to the East.  These islands are the gathering places of the world’s largest Continent, the Pacific. We of this continent know that her birth waters are our connection.  We also know that she is woman identified. It is no surprise therefore that from Hawai’i to the north to Aotearoa in the south the positioning of women in each of these societies bears a different story to that of the women of the continent of Europe.  This reality lived out in Hawai’i means women shared with men the ultimate leadership of peoples.  This location of women power is named Kuhinanui. Many remarkable women of Hawai’i occupied this position.  From times of peace throughout to the first clash with imposed new culture, women of Hawai’i led, bled, struggled, defied and kept the kukui of self belief burning. Genealogically Hawai’i is connected to her other sisters throughout the Pacific.  The story of Kuhinanui Liliuokalani is poignant.

year: 1993