title: Chemical aspects of saponin bioactivity and ovine photosensitization diseases

authors: Loader, Jared I.

abstract: A general review of saponin chemistry, bioactivities and of chemical aspects of saponin-associated hepatogenous photosensitization of ruminants (sheep, goats, and cattle) is presented. 
A field trial was undertaken to explore the genin dose/response hypothesis that saponins produced by the plant Narthecium ossifragum may be the direct cause of the toxicity leading to the photosensitization disease alveld seen in Norwegian lambs grazing N. ossifragum containing pastures. The genin content of N. ossifragum leaves from 2 control and 2 outbreak pasture areas, in a region of Norway known for periodic livestock outbreaks of alveld, ranged from 4553 to 10879 mg/kg DM. No significant statistical differences in the mean sapogenin content from the 2 control and 2 outbreak pasture areas were found. Total faecal sapogenin levels determined for lambs grazing the 2 control and 2 outbreak areas ranged from 973 to 36314 mg/kg DM. No obvious relationships between faecal sapogenin levels of lambs exhibiting external alveld symptoms and lambs not exhibiting symptoms were identified. The data does not support the hypothesis that saponins are the sole causative agent for the development of alveld disease symptoms in lambs grazing pastures containing N. ossifragum. 
Genin levels in Scottish collections of N. ossifragum plant material, gathered from pasture on which sheep were photosensitized, were determined. Elevated levels of sarsasapogenin and smilagenin containing saponins were found in flower heads (ca. 18000 mg/kg DM). Significant levels of free genins were found in plant roots (832-1184 mg/kg DM). The percentage contribution (ca. 45-65%) of smilagenin (a 25R-genin) in the Scottish samples was typically 2-4 times greater than is the case for Norwegian collections of N. ossifragum (typically ca. 10-15%). 
A field trial involving the daily intraruminal administration of a 1:4 mixture of [2,2,4,4-2H4]sarsasapogenin and [2,2,4,4-2H4]episarsasapogenin to 4 ewes, their twin lambs, and to 3 weaned lambs over a 21 day period was undertaken in Norway. The results showed that the isotope-dilution methodology can be applied under field conditions to estimate the uptake of sapogenins from plant material under conditions characteristically associated with the development of al veld. 
Mother ewes, on average, consumed 2-3 times the daily weight of N. ossifragum (ca. 700-750 g DM/day) consumed by the lambs (ca. 200-250 g DM/day). Percentage deuterium ratios, determined using SIM GC-MS protocols, while lower that anticipated, were consistent across the animals involved in the trial (between ca. 2-3%). Average N. ossifragum intakes, calculated relative to live-weights, were determined for all sheep involved in the trial. No correlation between the quantity of N. ossifragum consumed and live-weight (g DM day/kg) and the development of alveld was identified. 
The synthesis of sarsasapogenin β-D-galactoside, episarsasapogenin β-D-glucoside, episarsasapogenin β-D-galactoside, betulin 3-(β-D-glucoside) and betulin 3,28-(β-D-diglucoside), was performed via Koenig-Knorr coupling of sarsasapogenin, episarsasapogenin, or betulin with 2,3,4,6-tetra-0-acetyl-α-D-glucopyranosyl bromide, or the corresponding galactoside, followed by hydrolysis of the resulting tetra-0-acetyl-β-Dglycosides.Structures of intermediates, and product glycosides were established using a combination of ES-MS and one- and two-dimensional NMR spectral data. 
The synthesized sarsasapogenin, episarsasapogenin and betulin saponins, 4-methoxyfuran-2(5H)-one 5-(β-D-glucoside), Yucca schidigera 70° Brix extract, a methanol conjugate extract of N. ossifragum leaves and the active triketone fraction (triketone oil) from East Cape Manuka oil were subjected to a bioactivity evaluation against a range of bacterial and fungal organisms using the agar gel well diffusion technique. A possible structure-activity relationship amongst the synthesized saponins is discussed. 
The activity of triketone oil against two fish-pathogenic strains of Saprolegnia parasiticawas evaluated. The evaluation, performed in vitro, required the use of small percentages of water-miscible organic solvents and phosphate buffer solutions to obtain homogenous aqueous solutions. Inhibition of S. parasitica growth was seen at triketone oil concentrations of: (i) 150 and 200 ppm using aqueous solutions containing 0.5% and 1.0% pyrrolidinone, each containing 0.5% Tween 80 and (ii) at 150 and 200 ppm, at both pH 7 .0 and 7.5 of a 0.25 molL-1  phosphate buffer solution. An in vivo toxicity trial found that East Cape triketone oil at 200 ppm was acutely toxic to Atlantic salmon fry, with a 50% mortality rate after a 2 h single dose static bath exposure.

text: Chemical aspects of saponin bioactivity and ovine photosensitization diseases A general review of saponin chemistry, bioactivities and of chemical aspects of saponin-associated hepatogenous photosensitization of ruminants (sheep, goats, and cattle) is presented. 
A field trial was undertaken to explore the genin dose/response hypothesis that saponins produced by the plant Narthecium ossifragum may be the direct cause of the toxicity leading to the photosensitization disease alveld seen in Norwegian lambs grazing N. ossifragum containing pastures. The genin content of N. ossifragum leaves from 2 control and 2 outbreak pasture areas, in a region of Norway known for periodic livestock outbreaks of alveld, ranged from 4553 to 10879 mg/kg DM. No significant statistical differences in the mean sapogenin content from the 2 control and 2 outbreak pasture areas were found. Total faecal sapogenin levels determined for lambs grazing the 2 control and 2 outbreak areas ranged from 973 to 36314 mg/kg DM. No obvious relationships between faecal sapogenin levels of lambs exhibiting external alveld symptoms and lambs not exhibiting symptoms were identified. The data does not support the hypothesis that saponins are the sole causative agent for the development of alveld disease symptoms in lambs grazing pastures containing N. ossifragum. 
Genin levels in Scottish collections of N. ossifragum plant material, gathered from pasture on which sheep were photosensitized, were determined. Elevated levels of sarsasapogenin and smilagenin containing saponins were found in flower heads (ca. 18000 mg/kg DM). Significant levels of free genins were found in plant roots (832-1184 mg/kg DM). The percentage contribution (ca. 45-65%) of smilagenin (a 25R-genin) in the Scottish samples was typically 2-4 times greater than is the case for Norwegian collections of N. ossifragum (typically ca. 10-15%). 
A field trial involving the daily intraruminal administration of a 1:4 mixture of [2,2,4,4-2H4]sarsasapogenin and [2,2,4,4-2H4]episarsasapogenin to 4 ewes, their twin lambs, and to 3 weaned lambs over a 21 day period was undertaken in Norway. The results showed that the isotope-dilution methodology can be applied under field conditions to estimate the uptake of sapogenins from plant material under conditions characteristically associated with the development of al veld. 
Mother ewes, on average, consumed 2-3 times the daily weight of N. ossifragum (ca. 700-750 g DM/day) consumed by the lambs (ca. 200-250 g DM/day). Percentage deuterium ratios, determined using SIM GC-MS protocols, while lower that anticipated, were consistent across the animals involved in the trial (between ca. 2-3%). Average N. ossifragum intakes, calculated relative to live-weights, were determined for all sheep involved in the trial. No correlation between the quantity of N. ossifragum consumed and live-weight (g DM day/kg) and the development of alveld was identified. 
The synthesis of sarsasapogenin β-D-galactoside, episarsasapogenin β-D-glucoside, episarsasapogenin β-D-galactoside, betulin 3-(β-D-glucoside) and betulin 3,28-(β-D-diglucoside), was performed via Koenig-Knorr coupling of sarsasapogenin, episarsasapogenin, or betulin with 2,3,4,6-tetra-0-acetyl-α-D-glucopyranosyl bromide, or the corresponding galactoside, followed by hydrolysis of the resulting tetra-0-acetyl-β-Dglycosides.Structures of intermediates, and product glycosides were established using a combination of ES-MS and one- and two-dimensional NMR spectral data. 
The synthesized sarsasapogenin, episarsasapogenin and betulin saponins, 4-methoxyfuran-2(5H)-one 5-(β-D-glucoside), Yucca schidigera 70° Brix extract, a methanol conjugate extract of N. ossifragum leaves and the active triketone fraction (triketone oil) from East Cape Manuka oil were subjected to a bioactivity evaluation against a range of bacterial and fungal organisms using the agar gel well diffusion technique. A possible structure-activity relationship amongst the synthesized saponins is discussed. 
The activity of triketone oil against two fish-pathogenic strains of Saprolegnia parasiticawas evaluated. The evaluation, performed in vitro, required the use of small percentages of water-miscible organic solvents and phosphate buffer solutions to obtain homogenous aqueous solutions. Inhibition of S. parasitica growth was seen at triketone oil concentrations of: (i) 150 and 200 ppm using aqueous solutions containing 0.5% and 1.0% pyrrolidinone, each containing 0.5% Tween 80 and (ii) at 150 and 200 ppm, at both pH 7 .0 and 7.5 of a 0.25 molL-1  phosphate buffer solution. An in vivo toxicity trial found that East Cape triketone oil at 200 ppm was acutely toxic to Atlantic salmon fry, with a 50% mortality rate after a 2 h single dose static bath exposure.

year: 2004

title: From event streams to process models and back: Challenges and opportunities

authors: Soffer, Pnina

subjects: Science & Technology

abstract: The domains of complex event processing (CEP) and business process management (BPM) have different origins but for many aspects draw on similar concepts. While specific combinations of BPM and CEP have attracted research attention, resulting in solutions to specific problems, we attempt to take a broad view at the opportunities and challenges involved. We first illustrate these by a detailed example from the logistics domain. We then propose a mapping of this area into four quadrants — - two quadrants drawing from CEP to create or extend process models and two quadrants starting from a process model to address how it can guide CEP. Existing literature is reviewed and specific challenges and opportunities are indicated for each of these quadrants. Based on this mapping, we identify challenges and opportunities that recur across quadrants and can be considered as the core issues of this combination. We suggest that addressing these issues in a generic manner would form a sound basis for future applications and advance this area significantly.

text: From event streams to process models and back: Challenges and opportunities The domains of complex event processing (CEP) and business process management (BPM) have different origins but for many aspects draw on similar concepts. While specific combinations of BPM and CEP have attracted research attention, resulting in solutions to specific problems, we attempt to take a broad view at the opportunities and challenges involved. We first illustrate these by a detailed example from the logistics domain. We then propose a mapping of this area into four quadrants — - two quadrants drawing from CEP to create or extend process models and two quadrants starting from a process model to address how it can guide CEP. Existing literature is reviewed and specific challenges and opportunities are indicated for each of these quadrants. Based on this mapping, we identify challenges and opportunities that recur across quadrants and can be considered as the core issues of this combination. We suggest that addressing these issues in a generic manner would form a sound basis for future applications and advance this area significantly.

year: 2019

title: Demystifying a relationship between voluntary work and Māori

authors: Te Momo, Oliver Helena Fiona

abstract: The purpose of this thesis is to provide evidence that critically reviews the relationship between Māori and voluntary work in social service organisations. Since colonisation very little research has been initiated that investigated the involvement of Māori in voluntary activity yet recent statistics show that Māori are the highest participants in this type of work. This thesis provides an analysis of the relationship of Māori to voluntary work and its evolution in a Colonial State, Liberal State, Welfare State, and Neo-Liberal State in New Zealand. Three perspectives of Māori voluntary work provide the foundation for the analysis of this relationship. The first perspective describes voluntary work from a personal experience as an insider. The second perspective explores literature that records Māori involvement in voluntary activity. The third perspective documents life experiences from Māori voluntary workers in New Zealand communities. The three perspectives provide an empirical foundation for the type of relationship that has developed between Māori and voluntary work; Māori and the State; Māori and their place in New Zealand society. My interest in Te Ao Māori (the Māori world) as a valid and thriving ontological position and my academic interest in critical theory provide the theoretical lens for my analysis. 

Personal experience as a Māori volunteer opened doors to the communities I entered and added strength to the research, the first perspective. Western research in Māori communities often by non-Māori researchers, was conducted to gather knowledge for Western policy makers. Māori knowledge was not recognised as valid and the people were treated as objects. Knowing this, I searched for an approach that valued Māori participants, valued Māori people, and contained cultural aspects that separated the procedure from Western research. A review of literature, the second perspective, introduced a cultural approach to research termed kaupapa Māori research, generated out of and for Te Ao Māori detailed further in Chapter Three.

Participants’ life experiences coupled with literature provide a wealth of knowledge and a testimony to the type of relationship that exists between Māori and voluntary work. Criticism from Māori communities as to the exploitation of Māori volunteers has swelled in recent years so that the environment volunteers work in is no longer attractive to Māori people. Therefore, documenting the life experiences of Māori who participate in voluntary work as the primary source of information was imperative and produced evidence to describe the relationship between Māori and voluntary work in the thesis. A triangular study: case study, community study, and cross-section study (Chapters Six, Seven, and Eight), provide the ‘grass roots voices’ and represent the third perspective. 

My observation of Māori organisations’ involvement in voluntary work generated in me a deep concern in what appeared to be an involvement in activity that improved neither the lives of the volunteers nor the wider problems to which they attributed their aroha. This involvement activity is a product of historical developments whereby the Western ideology of voluntary work became confused with a Māori ideology of collective participation. This confusion has created an environment where Māori voluntary organisations are working unpaid with insufficient resources in oppressive conditions in the attempt to provide social solutions. I argue that the Māori ideology of collective participation has been co-opted in the emerging conflict of neo-liberalism to provide social services in communities which government agencies exploit. In conclusion, the thesis is a journey through the world of voluntary work for Māori in communal organisations.

text: Demystifying a relationship between voluntary work and Māori The purpose of this thesis is to provide evidence that critically reviews the relationship between Māori and voluntary work in social service organisations. Since colonisation very little research has been initiated that investigated the involvement of Māori in voluntary activity yet recent statistics show that Māori are the highest participants in this type of work. This thesis provides an analysis of the relationship of Māori to voluntary work and its evolution in a Colonial State, Liberal State, Welfare State, and Neo-Liberal State in New Zealand. Three perspectives of Māori voluntary work provide the foundation for the analysis of this relationship. The first perspective describes voluntary work from a personal experience as an insider. The second perspective explores literature that records Māori involvement in voluntary activity. The third perspective documents life experiences from Māori voluntary workers in New Zealand communities. The three perspectives provide an empirical foundation for the type of relationship that has developed between Māori and voluntary work; Māori and the State; Māori and their place in New Zealand society. My interest in Te Ao Māori (the Māori world) as a valid and thriving ontological position and my academic interest in critical theory provide the theoretical lens for my analysis. 

Personal experience as a Māori volunteer opened doors to the communities I entered and added strength to the research, the first perspective. Western research in Māori communities often by non-Māori researchers, was conducted to gather knowledge for Western policy makers. Māori knowledge was not recognised as valid and the people were treated as objects. Knowing this, I searched for an approach that valued Māori participants, valued Māori people, and contained cultural aspects that separated the procedure from Western research. A review of literature, the second perspective, introduced a cultural approach to research termed kaupapa Māori research, generated out of and for Te Ao Māori detailed further in Chapter Three.

Participants’ life experiences coupled with literature provide a wealth of knowledge and a testimony to the type of relationship that exists between Māori and voluntary work. Criticism from Māori communities as to the exploitation of Māori volunteers has swelled in recent years so that the environment volunteers work in is no longer attractive to Māori people. Therefore, documenting the life experiences of Māori who participate in voluntary work as the primary source of information was imperative and produced evidence to describe the relationship between Māori and voluntary work in the thesis. A triangular study: case study, community study, and cross-section study (Chapters Six, Seven, and Eight), provide the ‘grass roots voices’ and represent the third perspective. 

My observation of Māori organisations’ involvement in voluntary work generated in me a deep concern in what appeared to be an involvement in activity that improved neither the lives of the volunteers nor the wider problems to which they attributed their aroha. This involvement activity is a product of historical developments whereby the Western ideology of voluntary work became confused with a Māori ideology of collective participation. This confusion has created an environment where Māori voluntary organisations are working unpaid with insufficient resources in oppressive conditions in the attempt to provide social solutions. I argue that the Māori ideology of collective participation has been co-opted in the emerging conflict of neo-liberalism to provide social services in communities which government agencies exploit. In conclusion, the thesis is a journey through the world of voluntary work for Māori in communal organisations.

year: 2003