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Evechinus chloroticus (commonly known as kina) is a sea urchin species endemic to New Zealand. Its roe is a culinary delicacy to the indigenous Māori and a globally exported food product. Echinochrome A (Ech A) is a bioactive compound isolated from the waste product of kina shells and spines; however, the molecular mechanisms of Ech A bioactivity are not well understood, partly due to Ech A never being studied using unbiased genome‐wide analysis. To explore the high‐value pharmaceutical potential of kina food waste, we obtained unbiased functional genomic and proteomic profiles of yeast cells treated with Echinochrome A. Abundance was measured for 4100 proteins every 30 min for four hours using fluorescent microscopy, resulting in the identification of 92 proteins with significant alterations in protein abundance caused by Ech A treatment that were over‐represented with specific changes in DNA replication, repair and RNA binding after 30 min, followed by specific changes in the metabolism of metal ions (specifically iron and copper) from 60–240 min. Further analysis indicated that Ech A chelated iron, and that iron supplementation negated the growth inhibition caused by Ech A. Via a growth‐based genome‐wide analysis of 4800 gene deletion strains, 20 gene deletion strains were sensitive to Ech A in an iron‐dependent manner. These genes were over‐represented in the cellular response to oxidative stress, suggesting that Ech A suppressed growth inhibition caused by oxidative stress. Unexpectedly, genes integral to cardiolipin and inositol phosphate biosynthesis were required for Ech A bioactivity. Overall, these results identify genes, proteins, and cellular processes mediating the bioactivity of Ech A. Moreover, we demonstrate unbiased genomic and proteomic methodology that will be useful for characterizing bioactive compounds in food and food waste. [ABSTRACT FROM AUTHOR]

The physiology of the New Zealand sea urchin Evechinus chloroticus was evaluated through feeding, respiration, growth and gonad growth in adult animals acclimated for 90 days at 18 °C (annual mean temperature) and 24 °C (ambient summer temperature (21 °C) + 3 °C). Measured parameters with representative rates of assimilation efficiency were used to calculate scope for growth (SfG) for each treatment. All physiological parameters were negatively affected at 24 °C, showing a decrease in feeding rate which coincided with negative growth and gonad development at the end of the acclimation period, and a decrease in respiration rate suggesting metabolic depression. Histology of gonad samples after the acclimation period also showed no gametic material in animals acclimated at 24 °C. All animals acclimated at 24 °C had negative growth, differing from the calculated SfG which indicated that the animals had sufficient energy for production. The results suggest that calculated SfG in echinoderms should be used together with actual measurements of growth in individuals as, by itself, SfG may underestimate the actual effect of ocean warming when animals are exposed to stressful conditions. Overall, considering the total loss of reproductive output observed in E. chloroticus at higher temperatures, an increase in seawater temperature could dramatically influence the persistence of northern populations of this species, leading to flow-on effects in the subtidal ecosystem. [ABSTRACT FROM AUTHOR]

Seawater temperature is an important environmental factor for the early life stages of marine invertebrates. In this study we evaluated and described the effects of temperature during early development of E. chloroticus, identifying the optimum temperature range and upper thermal limit for successful development. The temperature range evaluated was between 15–24°C which included the normal seawater temperatures during the spawning season in northern New Zealand, as well as the highest temperature projected by the IPCC for this region due to global warming (1–3°C by the year 2100). Gametes from several females and males were used in the experiment. Fertilization was carried out at different temperatures and development was monitored at different time points after fertilization in each temperature. The development rate of E. chloroticus increased with an increase in seawater temperature. However, at temperatures higher than 21.5°C the amount of abnormal development reached ∼30%. The optimum temperature for early development was between 15–21°C, whereas the upper thermal limit was ∼24°C. Therefore, early development of E. chloroticus is negatively affected by an increase in seawater temperature of ∼3–4°C above current seawater temperature levels in northern New Zealand. The thermal sensitivity of early life stages of E. chloroticus could affect survival rates during early development of this species in a global warming scenario, which could impair recruitment in populations which are exposed to higher temperatures, leading to possible distributional shifts of this species. [ABSTRACT FROM AUTHOR]

Abstract: Inherent variability in the New Zealand sea urchin, Evechinus chloroticus gonads quality poses a significant hurdle in the design and implementation of processing and shelf-life trials. This study investigated if the five gonads collected from an individual animal were sufficiently similar to act as replicates in handling and processing trials. For gonads collected from a single urchin, the average standard deviation (SD) and coefficient of variation (CV) of the moisture content (SD: 059; CV: 0.01), protein (SD: 2.45; CV: 0.30), glucose (SD: 0.05; CV: 0.23), glycogen (SD: 1.40; CV: 0.24), alanine (SD: 0.05; CV: 0.23), glycine (SD: 40.74; CV: 0.13); asparagine (SD: 0.27; CV: 0.14), glutamate (SD: 1.93; CV: 0.14), methionine (SD: 0.30; CV: 0.07), valine (SD: 2.20; CV: 0.07), IMP (SD: 2.29; CV: 0.08) and K-value (SD: 1.73; CV: 0.06) were greater than the SD and CV of gonads recovered from different urchins for moisture content (SD: 2.85; CV: 0.04), protein (SD: 7.89; CV: 0.60), glucose (SD: 0.09; CV: 0.39), glycogen (SD: 2.09; CV: 0.30), alanine (SD: 0.09; CV: 0.39), glycine (SD: 239.98; CV: 0.77), asparagine (SD: 01.09; CV: 0.52), glutamate (SD: 12.17; CV: 1.02), methionine (SD: 3.09; CV: 0.80), valine (SD: 313.93; CV: 0.80), IMP (SD: 7.41; CV: 0.22) and K-value (SD: 7.47; CV: 0.21). It was therefore concluded gonads from a single urchin could be used as a valid means of reducing the initial inherent variability in the starting raw material when conducting shelf-life and processing trials. [Copyright &y& Elsevier]

The influence of season, gender and sexual maturity on the biochemical composition (moisture, protein, total lipids, triglycerides, cholesterol, phospholipids, free amino acids, glucose and glycogen) of gonads from the endemic New Zealand sea urchin Evechinus chloroticus was investigated. Gonads were obtained from urchins during the austral autumn, winter, summer and spring, over a 23-month period. Biochemical differences between genders were less pronounced in autumn (March to May) and winter (June to August) when more nutritive cells were present in the gonads, and more distinct over spring (September to November) and summer (December to February) months as the gametogenic cells matured, thus highlighting the importance of assessing testes and ovaries separately during biochemical analysis. Differences in the biochemical composition of testes and ovaries were the least pronounced during autumn, which suggests this will be the best season to harvest E. chloroticus in order to enhance taste and flavour, and reduce variability. [ABSTRACT FROM AUTHOR]

Increased atmospheric CO emissions are inducing changes in seawater carbon chemistry, lowering its pH, decreasing carbonate ion availability and reducing calcium carbonate saturation state. This phenomenon, known as ocean acidification, is happening at a faster rate in cold regions, i.e., polar and sub-polar waters. The larval development of Arbacia dufresnei from a sub-Antarctic population was studied at high (8.0), medium (7.7) and low (7.4) pH waters. The results show that the offspring from sub-Antarctic populations of A. dufresnei are susceptible to a development delay at low pH, with no significant increase in abnormal forms. Larvae were isometric between pH treatments. Even at calcium carbonate (CaCO) saturation states (of both calcite and aragonite, used as proxies of the magnesium calcite) <1, skeleton deposition occurred. Polar and sub-polar sea urchin larvae can show a certain degree of resilience to acidification, also emphasizing A. dufresnei potential to poleward migrate and further colonize southern regions. [ABSTRACT FROM AUTHOR]

Abstract: Sea urchin roe is a high value product; however, previous attempts to market the roe from the New Zealand sea urchin (Evechinus chloroticus) have been unsuccessful due to its inconsistent sensory quality. The current study investigated the odour active volatile profiles of roe from male and female sea urchins, harvested from two locations in New Zealand, using solvent assisted flavour evaporation (SAFE) extracts and a gas chromatography–olfactometry–finger span cross modality (GC–O–FSCM) method. Panellists detected 81 odour active compounds, 18 of which were identified using GC–mass spectrometry (MS). Generalised procrustes analysis (GPA) of the data revealed that there were differences in the volatile profile that were location and gender specific. These differences may have contributed to the inconsistent sensory properties of sea urchin roe. The differences in volatile profiles between sea urchin populations and genders must be appreciated before developing effective strategies to produce consistent sea urchin roe quality. [Copyright &y& Elsevier]

Abstract: Roe from the sea urchin Evechinus chloroticus collected from locations in the North (Mathesons Bay) and South (Doubtful Sound) of New Zealand was characterised according to physical characteristics, sensory properties, and volatile composition. Objective assessment of roe sensory properties (appearance, odour, taste, flavour, texture, and aftertaste) was carried out by a trained sensory panel using descriptive sensory analysis. Proton transfer reaction-mass spectrometry (PTR-MS) was used for headspace analysis of roe, and data were collected over the mass range m/z 22–180. Sea urchins from the Northern population were significantly smaller, and had a lower roe index than those from the Southern population. Roe from Northern sea urchins were rated higher for the attributes of marine, seafood and sharp odour, bitter taste, herbaceous and metallic flavour, astringent texture, and metallic, bitter, and duration of aftertaste than roe from Southern sea urchins, which were rated higher for dairy odour, sweet taste, dairy flavour, moisture content and mouth coating. E. chloroticus roe was also differentiated based on gender by 26 sensory attributes. Volatile analysis significantly discriminated between roe from Northern and Southern sea urchins by 35 mass ions, and between genders of Southern sea urchins by five mass ions. [Copyright &y& Elsevier]

Abstract: An experiment testing the effects of elevated temperatures on roe enhancement of sea urchins Evechinus chloroticus collected from two widely separated sites in New Zealand was conducted over a 10 week period between September and December 2007. Groups of urchins from Central and Northern Populations were held at 18 °C, 20 °C, 22 °C and 24 °C and fed ad libitum a formulated moist feed. After 10 weeks there were no significant differences in GI between urchins held at 18 °C (15.32±0.47) and 20 °C (15.02±0.45) but the GI of urchins held at 22 °C were significantly lower (11.91±0.42) and those held at 24 °C were significantly lower again (8.69±0.33). The increase in GI from the initial GI followed the same pattern, with urchins held at 18 °C and 20 °C having a significantly greater increase than those held at 22 °C, which in turn had a significantly greater increase than those held at 24 °C. There was no significant difference in GI after 10 weeks between the urchins held at 24 °C and urchins that remained in the wild during the experimental period. Urchin survival was also significantly lower at higher temperatures and it was lower in the Central Population compared to the Northern Population, probably because the experimental temperatures exceeded the natural temperature range of the former. There were no significant differences between the increases in GI of the urchins collected from the two populations and held at each of the different experimental temperatures. The benefits from increasing the holding temperature for roe enhancement must be weighed against the increased cost of holding urchins at the higher temperatures. Roe enhancement of E. chloroticus should be carried out at temperatures less than 22 °C and the higher survivorship of urchins taken from populations with higher ambient seawater temperatures, compared with those collected from populations exposed to lower ambient seawater temperatures, must also be taken into consideration. [Copyright &y& Elsevier]

The article presents a study on the size structure of the sea urchin Evechinus chloroticus between 1998 and 2007 at 22 research sites in the Fiordland region in southwestern New Zealand. The study investigated the 22 surveyed research sites around four times and in each site the entire urchins were collected in a swath with a depth of 0 to 20 meters within the shore for 50 to 200 meters depending on density and cryptic juveniles. The study used an arranged random survey at depths of 5, 10, and 15 meters throughout the Fiordland-wide surveys in 2003, 2004, and 2006. Findings showed that the size structures of sea urchins are determined by the effects of availability of high quality food, and the involvement of estuarine circulation.

The article presents a study which looks into the potential impact of fishing on the ecosystem function, particularly the food web dynamics, in the northeastern part of New Zealand. A large-scale experimental framework of four marine reserves and oceanographic gradient in the area are noted to have been employed by the researchers of the study. Derived from their observations, it is believed that there can be an increase in sea urchins in the reduction of predatory snapper or Pagris auratus and lobster or Jasus edwardsii as much as there can be an indirect decrease in kelp biomass.

The article about the growth of Pseudechinus huttoni, sea urchin in New Zealand is presented. It normally inhabits the continental shelf, but in the fiords it is found in the shallower depths, which provide an opportunity to quantify growth of these deep water sea urchin using chemical tag recapture techniques. Continental shelf population was inferred from measured growth in the fiord population by comparing population statistics, morphometrics, and nutritional status.

Extensive research has shown that the early life stages of marine organisms are sensitive to ocean acidification (OA). Less is known, however, on whether larval settlement and metamorphosis may be affected, or by which mechanisms. These are key processes in the life cycle of most marine benthic organisms, since they mark the transition between the free swimming larval stage to benthic life. We investigated whether OA could affect the larval settlement success of the sea urchin Evechinus chloroticus , a key coastal species with ecological, economic and cultural importance in New Zealand. We performed four settlement experiments to test whether reduced seawater pH (ranging from 8.1 to 7.0, at an interval of ~0.2 pH units) alters larval settlement and metamorphosis success. Our results show that settlement success was not significantly reduced when the larvae were exposed to a range of reduced seawater pH treatments (8.1–7.0) at time of settlement (on direct effects). Similarly, when presented with crustose coralline algae (CCA) pre-conditioned in seawater pH of either pH 8.1 or 7.7 for 28 days, larval settlement success remained unaltered (on indirect effects). We conclude that competent larvae in this species are resilient to OA at time of settlement. Further research on a range of taxa that vary in settlement selectivity and behaviour is needed in order to fully understand the effects of OA on the life cycle of marine invertebrates and the consequences it might have for future coastal marine ecosystems. • Settlement success of E. chloroticus was unaffected when left to settle in a range of reduced seawater pH (7.0 to 8.1). • Larval settlement success remained unaltered in presence of CCA pre-conditioned for 28 days at either ambient or reduced pH (7.7). • Larvae did not lose their ability to recognize their preferred settlement substrate in presence of reduced seawater pH. • No interactive effects were observed between seawater pH and preconditioned substrates on the larval settlement success. [ABSTRACT FROM AUTHOR]