Towards the development of innovative multi-mycotoxin reference materials as promising metrological tool for emerging and regulated mycotoxin analyses

The interest in LC-MS/MS multi-mycotoxin methods unveiled an urgent need for multi-mycotoxin reference material. A multi-fusariotoxin, including deoxynivalenol (DON); zearalenone (ZEN); T-2 toxin (T-2); HT-2 toxin (HT-2); enniatin A, A1, B, and B1 (ENNs); and beauvericin (BEA), contaminated wheat flour was obtained by inoculation Fusarium spp. strains. The candidate material has successfully passed the homogeneity test and submitted to an international interlaboratory study achieved by 19 laboratories from 11 countries using their routine analytical method. The dispersion of the results for ZEN and BEA did not allow the derivation of reliable consensus values, while the assignment was only possible for DON, HT-2, T-2, and ENN A. No link was found between the methods used by the participants and the results. Significant changes in dry matter contents (≥±1.4 % of the initial dry matter) and significant changes in ergosterol contents (≥±10 %) did not occur. Using the mycotoxin contents in wheat flour stored at ?80 °C as reference values, statistically significant decreases were observed only for T-2 contents at +24 °C, in contrast to the storage at ?20 and +4 °C. For the other involved toxins, the candidate material was found to be stable at ?20, +4, or +24 °C. Based on the T-2 decreases, a shelf life of 6 years was derived from isochronous study when the material is kept at ?20 °C. At room temperature (e.g., +24 °C) or higher, this time validity drastically decreases down to 6 months. The development of this metrological tool is an important step towards food and feed quality control using multi-mycotoxin analyses. In vivo animal experiments using multi-mycotoxin-contaminated feeds dealing with the carryover or mitigation could further benefit from the methodology of this work.     

Acute Toxicity of Arsenic under Different Temperatures and Salinity Conditions on the White Shrimp Litopenaeus vannamei

The aim of this study was to determine acute toxicity in the post larvae of the white shrimp Litopenaeus vannamei after 96 h of exposure to dissolved arsenic under three different temperatures and salinity conditions. Recent reports have shown an increase in the presence of this metalloid in coastal waters, estuaries, and lagoons along the Mexican coast. The white shrimp stands out for its adaptability to temperature and salinity changes and for being the main product for many commercial fisheries; it has the highest volume of oceanic capture and production in Mexican shrimp farms. Lethal concentrations (LC₅₀–96 h) were obtained at nine different combinations (3?×?3 combinations in total) of temperature (20, 25, and 30 °C) and salinity (17, 25, and 33) showing mean LC₅₀–96 h values (±standard error) of 9.13?±?0.76, 9.17?±?0.56, and 6.23?±?0.57 mgAs?L^?1(at 20 °C and 17, 25, and 33 salinity); 12.29?±?2.09, 8.70?±?0.82, and 8.03?±?0.59 mgAs?L^?1 (at 25 °C and 17, 25, and 33 salinity); and 7.84?±?1.30, 8.49?±?1.40, and 7.54?±?0.51 mgAs?L^?1 (at 30 °C and 17, 25, and 33 salinity), respectively. No significant differences were observed for the optimal temperature and isosmotic point of maintenance (25 °C–S 25) for the species, with respect to the other experimental conditions tested, except for at 20 °C–S 33, which was the most toxic. Toxicity under 20 °C–S 33 conditions was also higher than 25 °C–S 17 and 20 °C (S 17 or 25). The least toxic condition was 25 °C–S 17. All this suggests that the toxic effect of arsenic is not affected by temperature changes; it depends on the osmoregulatory pattern developed by the shrimp, either hyperosmotic at low salinity or hiposmotic at high salinity, as observed at least on the extreme salinity conditions here tested (17 and 33). However, further studies testing salinities near the isosmotic point (between 20 and 30 salinities) are needed to clarify these mechanisms.     

Effect of temperature on the development of Saccharina japonica gametophytes

Spores (collected at 10?±?1 °C, 2 h after releasing) and young gametophytes (newly generated from spores cultured at 10?±?1 °C for 8 days) of Saccharina japonica were first cultured at 15?±?1, 19?±?1, and 23?±?1 °C for various times (2, 5, and 8 days) and then at 10?±?1 °C (culturing patterns S and G, respectively). Spores were also cultured at a constant of 10?±?1 °C (pattern C) and used as the control. The length and percentage of young gametophytes, size and percentage of gametophytes, and ratio of female to male gametophytes were measured in order to determine the effect of temperature on the development of gametophytes. Temperature and exposure time of spores and young gametophytes at the first culturing temperature significantly affected the development of gametophytes as were indicated by all biological parameters except the ratio of female to male gametophytes. The spores were more sensitive to temperature than young gametophytes. Gametophytes developed from the spores that survived temperature stress can recover their growth. High temperature selection at the early developmental stages of gametophytes was effective for screening gametophytes applicable for breeding high temperature-resistant varieties and hybrids.     

Effects of constant and variable temperatures on development and reproduction of the two-spotted spider mite Tetranychus urticae (Acari: Tetranychidae)

We focused on the influence of different temperature amplitudes on development and reproduction of the two-spotted spider mite, Tetranychus urticae Koch, at a 16:8 (L:D) h photoperiod and 60–95 % RH. The temperature amplitudes varied from 0 to 24 °C in steps of 6 °C; i.e. 22 ± 0, 22 ± 3, 22 ± 6, 22 ± 9 and 22 ± 12 °C. Temperature changed every 24 h between a low and an upper value, but without changing the average temperature (22 °C). The number of eggs laid by five females for 24 h was slightly lower at 22 ± 12 °C than at constant temperature (22 ± 0 °C), and egg hatchability differed among the five temperature regimes. Developmental time at 22 ± 0 °C was shorter than that at 22 ± 3 and 22 ± 6 °C, but longer than that at 22 ± 9 and 22 ± 12 °C. The oviposition period, total fecundity per female and adult longevity gradually decreased with increasing amplitudes. Sex ratio was similar at all five temperature regimes. The intrinsic rate of natural increase (r _m) was affected by temperature amplitude and the r _m-values at all amplitudes except 22 ± 12 °C were higher than that at constant temperature. Thus, this study showed that variable temperature regimes influence population growth rates of T. urticae and that large amplitude regimes are stressful for this species.     

GH–IGF system regulation of attenuated muscle growth and lipolysis in Atlantic salmon reared at elevated sea temperatures

Growth regulation in adult Atlantic salmon (1.6 kg) was investigated during 45 days in seawater at 13, 15, 17, and 19 °C. We focused on feed intake, nutrient uptake, nutrient utilization, and endocrine regulation through growth hormone (GH), insulin-like growth factors (IGF), and IGF-binding proteins (IGFBP). During prolonged thermal exposure, salmon reduced feed intake and growth. Feed utilization was reduced at 19 °C after 45 days compared with fish at lower temperatures, and body lipid storage was depleted with increasing water temperature. Although plasma IGF-1 concentrations did not change, 32-Da and 43-kDa IGFBP increased in fish reared at ≤17 °C, and dropped in fish reared at 19 °C. Muscle igf1 mRNA levels were reduced at 15 and 45 days in fish reared at 15, 17, and 19 °C. Muscle igf2 mRNA levels did not change after 15 days in response to increasing temperature, but were reduced after 45 days. Although liver igf2 mRNA levels were reduced with increasing temperatures after 15 and 45 days, temperature had no effect on igf1 mRNA levels. The liver igfbp2b mRNA level, which corresponds to circulating 43-kDa IGFBP, exhibited similar responses after 45 days. IGFBP of 23 kDa was only detected in plasma in fish reared at 17 °C, and up-regulation of the corresponding igfbp1b gene indicated a time-dependent catabolic response, which was not observed in fish reared at 19 °C. However, higher muscle ghr mRNA levels were detected in fish at 17 and 19 °C than in fish at lower temperatures, indicating lipolytic regulation in muscle. These results show that the reduction of muscle growth in large salmon is mediated by decreased igf1 and igf2 mRNA levels in addition to GH-associated lipolytic action to cope with prolonged thermal exposure. Accordingly, 13 °C appears to be a more optimal temperature for the growth of adult Atlantic salmon at sea.     

Life history traits of Blaptostethus pallescens (Hemiptera: Anthocoridae), a candidate for use in augmentative biological control in Egypt

Blaptostethus pallescens Poppius (Hemiptera: Anthocoridae) is an abundant native predator in mango orchards and other cropping systems in Egypt. To determine suitable mass-rearing conditions for this little-studied species, we assessed some of its biological characteristics. Testing its thermal response at three constant temperatures (20, 25, 30 °C), showed that immature development time and adult longevity decreased with increasing temperature. Reproductive success of individual females was greatest when reared at 25 °C (84.3 ± 3.1 eggs) rather than at 20 °C (46.6 ± 2.0 eggs) or 30 °C (65.2 ± 2.5 eggs). Although B. pallescens reared at 25 °C had a significantly higher net reproductive rate (R ₀), which may be attributed to their relatively rapid development and high fecundity, we argue that 30 °C seems to be more convenient for rearing B. pallescens, as mean generation time (T) and doubling time (DT) are clearly shorter, thus more individuals could be reared per unit of time at 30 °C. Mating significantly reduced male and female longevity, as unmated adults lived 25–45 % longer than mated individuals did. Unmated females did not lay eggs, suggesting that mating is a prerequisite for egg maturation. Adult males and females performed best, in terms of longevity, when fed Ephestia kuehniella Zeller (Lepidoptera: Pyralidae) eggs instead of non-prey diets. However, diets of plant sap or pollen could sustain adults in times of limited egg availability. Because its biology is similar to that of other subtropical anthocorids already reared for augmentative releases, B. pallescens may be amenable to mass-rearing using already established techniques. Therefore, B. pallescens could be used to improve augmentative biological control in crops such as mango or maize in Egypt where it already naturally occurs, and therefore would not engender concerns over non-target effects that an exotic, generalist biological control agent would.     

The effect of temperature on growth and lipid and fatty acid composition on marine microalgae used for biodiesel production

Cultivation temperature is one of the major factors affecting the growth and lipid accumulation of microalgae. In this study, the effects of temperature on the growth, lipid content, fatty acid composition and biodiesel properties of the marine microalgae Chaetoceros sp. FIKU035, Tetraselmis suecica FIKU032 and Nannochloropsis sp. FIKU036 were investigated. These species were cultured at different temperatures (25, 30, 35 and 40 °C). The results showed that the specific growth rate, biomass and lipid content of all microalgae decreased with increasing temperature. With regards to fatty acids, the presence of saturated fatty acids (SFAs) in T. suecica FIKU032 and Nannochloropsis sp. FIKU036 decreased with increasing temperature, in contrast with polyunsaturated fatty acids (PUFAs). Moreover, Chaetoceros sp. FIKU035 was the only species that could grow at 40 °C. The highest lipid productivity was observed in Chaetoceros sp. FIKU035 when cultivated at 25 °C (66.73 ± 1.34 mg L^?1 day^?1) and 30 °C (61.35 ± 2.89 mg L^?1 day^?1). Moreover, the biodiesel properties (cetane number, cold filter plugging point, kinematic viscosity and density) of the lipids obtained from this species were in accordance with biodiesel standards. This study indicated that Chaetoceros sp. FIKU035 can be considered as a suitable species for biodiesel production in outdoor cultivation.     

Purification, characterization and cloning of a thermotolerant isoamylase produced from Bacillus sp. CICIM 304

A novel thermostable isoamylase, IAM, was purified to homogeneity from the newly isolated thermophilic bacterium Bacillus sp. CICIM 304. The purified monomeric protein with an estimated molecular mass of 100 kDa displayed its optimal temperature and pH at 70 °C and 6.0, respectively, with excellent thermostability between 30 and 70 °C and pH values from 5.5 to 9.0. Under the conditions of temperature 50 °C and pH 6.0, the K _m and V _max on glycogen were 0.403 ± 0.018 mg/mg and 0.018 ± 0.001 mg/(min mg), respectively. Gene encoding IAM, BsIam was identified from genomic DNA sequence with inverse PCRs. The open reading frame of the BsIam gene was 2,655 base pairs long and encoded a polypeptide of 885 amino acids with a calculated molecular mass of 101,155 Da. The deduced amino acid sequence of IAM shared less than 40 % homology with that of microbial isoamylase ever reported, which indicated it was a novel isoamylase. This enzyme showed its obvious superiority in the industrial starch conversion process.     

Cloning,expression, and characterization of a thermostable glucose-6-phosphate dehydrogenase from <Emphasis Type="Italic">Thermoanaerobacter tengcongensis</Emphasis>

Glucose-6-phosphate dehydrogenases (G6PDs) are important enzymes widely used in bioassay and biocatalysis. In this study, we reported the cloning, expression, and enzymatic characterization of G6PDs from the thermophilic bacterium Thermoanaerobacter tengcongensis MB4 (TtG6PD). SDS-PAGE showed that purified recombinant enzyme had an apparent subunit molecular weight of 60 kDa. Kinetics assay indicated that TtG6PD preferred NADP⁺ (k _cat/K _m = 2618 mM^?1 s^?1, k _cat = 249 s^?1, K _m = 0.10 ± 0.01 mM) as cofactor, although NAD⁺ (k _cat/K _m = 138 mM^?1 s^?1, k _cat = 604 s^?1, K _m = 4.37 ± 0.56 mM) could also be accepted. The K _m values of glucose-6-phosphate were 0.27 ± 0.07 mM and 5.08 ± 0.68 mM with NADP⁺ and NAD⁺ as cofactors, respectively. The enzyme displayed its optimum activity at pH 6.8–9.0 for NADP⁺ and at pH 7.0–8.6 for NAD⁺ while the optimal temperature was 80 °C for NADP⁺ and 70 °C for NAD⁺. This was the first observation that the NADP⁺-linked optimal temperature of a dual coenzyme-specific G6PD was higher than the NAD⁺-linked and growth (75 °C) optimal temperature, which suggested G6PD might contribute to the thermal resistance of a bacterium. The potential of TtG6PD to measure the activity of another thermophilic enzyme was demonstrated by the coupled assays for a thermophilic glucokinase.     

Effect of polyphenols extracted from tamarind (Tamarindus indica L.) seed coat on pathophysiological changes and red blood cell glutathione peroxidase activity in heat-stressed broilers

The purpose of this study was to determine the effect of polyphenols extracted from the tamarind seed coat (PETSC) on glutathione peroxidase (GPx) activity, red blood cell parameters and bilirubin in heat-stressed broilers. One hundred forty-seven broilers, 18-days old were divided into two groups. In group 1, broilers were maintained at an environmental temperature of 26?±?2 °C throughout the experimental period. In group 2, the broilers were maintained at 38?±?2 °C (cyclic temperature: 26?±?2 °C; ?38?±?2 °C; and ?26?±?2 °C, and broilers were maintained at 38?±?2 °C for 6 h/ day) and received PETSC at a concentration of 0, 100, 200, 300, 400 or 500 mg/kg in their diet ad libitum. Parameters were investigated on days 1, 7, 14 and 21 of the experimental period. Results showed that GPx activity of heat-stressed broilers that received 100 mg/kg of PETSC in their diet was lower (P?<?0.05) than that in broilers fed the other concentrations. The mean total red blood cell count and hemoglobin concentration of heat-stressed broilers that received 100 mg/kg PETSC was higher (P?<?0.05) than those in broilers in group 1 and those fed the other concentrations. The mean bilirubin level in the excreta of heat-stressed broilers that received 100 mg/kg of PETSC was lower (P?<?0.05) than that in broilers that received 0, 300, 400 and 500 mg/kg of PETSC. This showed that PETSC could reduce GPx activity and bilirubin in feces, and increase red blood cell parameters in heat-stressed broilers.     

Biochemical characterization and high-level production of oxidized polyvinyl alcohol hydrolase from Sphingopyxis sp. 113P3 expressed in methylotrophic Pichia pastoris

The Sphingopyxis sp. 113P3 gene oph, encoding oxidized polyvinyl alcohol hydrolase (OPH), was optimized with the preferred codons of Pichia pastoris and ligated into the pPIC9K vector behind the α-factor signal sequence. The vector was then transfected into P. pastoris GS115 and genomic integration was confirmed. Large-scale production of recombinant protein was performed by induction with 14.4 g/L methanol at 22 °C in a 3-L bioreactor. The maximal OPH activity obtained was 68.4 U/mL, which is the highest activity reported. The optimal pH and temperature of recombinant OPH were 8.0 and 45 °C, respectively. OPH activity was stable over a pH range of 5.0–8.5, and at a maximal temperature of 45 °C. The K _cat /K _m of recombinant OPH was 598 mM^?1 s^?1, which was 4.27-fold higher than that of recombinant OPH derived from Escherichia coli. The improved catalytic efficiency of OPH expressed in recombinant P. pastoris makes it favorable for industrial applications.     

Effect of change in ambient temperature on core temperature during the daytime

In this study, the hypothesis is tested that continuous increases in ambient temperature (T_a) during daytime would give elevated core and skin temperatures, and consequently better thermal sensation and comfort. Rectal temperature (T_re), skin temperatures and regional dry heat losses at 7 sites were continuously measured for 10 Japanese male subjects in three thermal conditions: cond. 1, stepwise increases in T_a from 26 °C at 9 h00 to 30 °C at 18 h00; cond. 2, steady T_a at 28 °C from 9 h00 to 18 h00 and cond. 3, stepwise decreases in T_a from 30 °C at 9 h00 to 26 °C at 18 h00. Oxygen consumption was measured and thermal sensation and comfort votes were monitored at 15 min intervals. Body weight loss was measured at 1 h intervals. While T_re increased continuously in the morning period in any condition, it increased to a significantly greater (p?<?0.05) 36.9?±?0.3 °C at 18 h00 in cond. 1 relative to 36.7?±?0.28 °C in Cond. 2 and 36.5?±?0.37 °C in cond. 3. Better thermal comfort was observed in the afternoon and the evening in Cond.1 as compared with the other 2 conditions. Thus, a progressive and appropriate increase in T_a may induce optimal cycle in core temperature during daytime, particularly for a resting person.     

A novel structured bioreactor for solid-state fermentation

A novel patented solid-state bioreactor (251 L) with honeycomb loading device was designed and its performance was tested. First, this apparatus gave a 66.87 % of calculated loading coefficient (volume ratio), which was almost twofold compared with conventional fermenters. Next, considering the crucial effect of heat transfer on bed loading and microbial growth, the performance was validated by temperature variance during fermentation and spore viability of Bacillus cereus DM423. Air pressure pulsation or external water jacket was used to control temperature; the maximal temperature variation was 7.7 versus 19.8 °C, respectively during fermentation. The difference was mainly due to the continuous gas phase characterized by solid-state fermentation (SSF). The average living spores of (1.50 ± 0.07) × 10¹¹ cfu/g at 40 h obtained from the device was higher than (0.70 ± 0.03) × 10¹¹ cfu/g from flask at 48 h. The results indicated that this new loading bioreactor with air pressure pulsation could be a good prospect for industrialization of SSF employing bacterial cultures.     

Induction of gene expression in bacteria at optimal growth temperatures

Traditional temperature-sensitive systems use either heat shock (40–42 °C) or cold shock (15–23 °C) to induce gene expression at temperatures that are not the optimal temperature for host cell growth (37 °C). This impacts the overall productivity and yield by disturbing cell growth and cellular metabolism. Here, we have developed a new system which controls gene expression in Escherichia coli at more permissive temperatures. The temperature-sensitive cI857-P _L system and the classic lacI-P _lacO system were connected in series to control the gene of interest. When the culture temperature was lowered, the thermolabile cI857 repressor was activated and blocked the expression of lacI from P _L. Subsequently, the decrease of LacI derepressed the expression of gene of interest from P _lacO . Using a green fluorescent protein marker, we demonstrated that (1) gene expression was tightly regulated at 42 °C and strongly induced by lowering temperature to 25–37 °C; (2) different levels of gene expression can be induced by varying culture temperature; and (3) gene expression after induction was sustained until the end of the log phase. We then applied this system in the biosynthesis of acetoin and demonstrated that high yield and production could be achieved using temperature induction. The ability to express proteins at optimal growth temperatures without chemical inducers is advantageous for large-scale and industrial fermentations.     

High thermal tolerance of two Mediterranean cold-water coral species maintained in aquaria

In the Mediterranean deep-sea, scleractinian cold-water corals (CWC) are observed to survive at the uppermost end of their presumed thermal distribution range (4–13 °C). Here, we show that 2 common CWC species (i.e. Dendrophyllia cornigera and Desmophyllum dianthus) maintained in aquaria can indeed tolerate considerably elevated seawater temperatures (17.5 ± 0.1 °C), while growing at similar (D. dianthus) or significantly higher (D. cornigera) rates than conspecifics cultured in parallel for 87 days at ambient Mediterranean deep-sea temperature (12.5 ± 0.1 °C). Neither differences in coral appearance nor mortality were evident for both species at either temperature. D. dianthus grew significantly faster (0.23 ± 0.08 % day^?1) than D. cornigera (0.05 ± 0.01 % day^?1) under ambient thermal conditions. Growth of D. cornigera increased significantly (0.14 ± 0.07 % day^?1) at elevated temperature, while Desmophyllum dianthus growth showed no significant difference under both conditions. These findings suggest that D. dianthus and D. cornigera may be capable of surviving in warmer environments than previously reported, and thus challenge temperature as the paramount limiting environmental factor for the occurrence of some CWC species.     

Construction of a highly thermostable 1,3-1,4-β-glucanase by combinational mutagenesis and its potential application in the brewing industry

Objectives

To improve the thermostability and catalytic property of a mesophilic 1,3-1,4-β-glucanase by combinational mutagenesis and to test its effect in congress mashing.

Results

A mutant β-glucanase (rE-BglTO) constructed by combinational mutagenesis showed a 25 °C increase in optimal temperature (to 70 °C) a 19.5 °C rise in T ₅₀ value and a 15.6 °C increase in melting temperature compared to wild-type enzyme. Its half-life values at 60 and 70 °C were 152 and 99 min, which were 370 and 800 % higher than those of wild-type enzyme. Besides, its specific activity and k _cat value were 42,734 U mg^?1 and 189 s^?1 while its stability under acidic conditions was also improved. In flask fermentation, the catalytic activity of rE-BglTO reached 2381 U ml^?1, which was 63 % higher than that of wild-type enzyme. The addition of rE-BglTO in congress mashing decreased the filtration time and viscosity by 21.3 and 9.6 %, respectively.

Conclusions

The mutant β-glucanase showed high catalytic activity and thermostability which indicated that rE-BglTO is a good candidate for application in the brewing industry.

     

Alternating temperatures affect life table parameters of Phytoseiulus persimilis, Neoseiulus californicus (Acari: Phytoseiidae) and their prey Tetranychus urticae (Acari: Tetranychidae)

Increasing energy costs force glasshouse growers to switch to energy saving strategies. In the temperature integration approach, considerable daily temperature variations are allowed, which not only have an important influence on plant growth but also on the development rate of arthropods in the crop. Therefore, we examined the influence of two constant temperature regimes (15 °C/15 °C and 20 °C/20 °C) and one alternating temperature regime (20 °C/5 °C, with an average of 15 °C) on life table parameters of Phytoseiulus persimilis and Neoseiulus californicus and their target pest, the two-spotted spider mite Tetranychus urticae at a 16:8 (L:D) h photoperiod and 65 ± 5 % RH. For females of both predatory mites the alternating temperature regime resulted in a 25–30 % shorter developmental time as compared to the corresponding mean constant temperature regime of 15 °C/15 °C. The immature development of female spider mites was prolonged for 7 days at 15 °C/15 °C as compared to 20 °C/5 °C. With a daytime temperature of 20 °C, no differences in lifetime fecundity were observed between a nighttime temperature of 20 and 5 °C for P. persimilis and T. urticae. The two latter species did show a higher lifetime fecundity at 20 °C/5 °C than at 15 °C/15 °C, and their daily fecundity at the alternating regime was about 30 % higher than at the corresponding mean constant temperature. P. persimilis and T. urticae showed no differences in sex ratio between the three temperature regimes, whereas the proportion of N. californicus females at 15 °C/15 °C (54.2 %) was significantly lower than that at 20 °C/5 °C (69.4 %) and 20 °C/20 °C (67.2 %). Intrinsic rates of increase were higher at the alternating temperature than at the corresponding mean constant temperature for both pest and predators. Our results indicate that thermal responses of the studied phytoseiid predators to alternating temperature regimes used in energy saving strategies in glasshouse crops may have consequences for their efficacy in biological control programs.     

The thermal tolerance of crown-of-thorns (Acanthaster planci) embryos and bipinnaria larvae: implications for spatial and temporal variation in adult populations

To understand the role of sea temperature on the population biology of the crown-of-thorns sea star Acanthaster planci, the thermal window for embryonic and larval development was investigated. In two experiments, the response of embryos and larvae across 12 temperatures from 19.4 to 36.5 °C was quantified as the percentage of individuals reaching cleavage stage embryos, blastula, gastrula, early-bipinnaria, late-bipinnaria larvae or abnormal. Measurements were made at 7 times up to 72 h post-fertilisation, with the morphometrics of larvae measured in the 72-h sample. Acanthaster planci developed at temperatures between 19.4 and 33.2 °C, with a thermal window for development to the late-bipinnaria stage between 25.6 and 31.6 °C. Development rate, normal development and larval size were optimal at 28.7 °C, with development rates remaining relatively constant up to 31.6 °C. Rates of abnormality increased steadily (early embryonic stages) above 28.7 °C and was 100 % at temperatures approaching 33 °C. These experiments provide a more detailed insight into the response of A. planci developmental stages to temperature. The present day distribution of the species in eastern Australia overlap with the optimal thermal window for development to the late-bipinnaria stage (≈25–32 °C), implying a role of temperature in controlling population distributions and abundances. Despite this, short- or long-term temperature increases may not be a major modulator of the crown-of-thorns recruitment success, population dynamics and distribution in the future as no significant change in development rates, larval survival and growth occurred within this thermal window. Therefore, moderate (1–2 °C) increases in sea temperatures caused by El Niño or near-future ocean warming may not drive an increase in developmental and settlement success. Indeed, without any acclimation to warmer temperatures expected under near-future warming (+2 to 4 °C), climate change could ultimately reduce larval survival due to elevated mortality above the optimal development temperature.