Breaking the Barrier: A Study on Multi-drug Resistance in Breast Abscess at an Academic Malaysian Hospital.

BACKGROUND: In recent years, the increase in antibiotics usage locally has led to a worrying emergence of multi-drug resistant organisms (MDRO), with the Malaysian prevalence rate of methicillin-resistant Staphylococcus aureus (MRSA) ranging from 17.2 to 28.1% between 1999 and 2017. A study has shown that 7% of all non-lactational breast abscesses are caused by MRSA. Although aspiration offers less morbidities compared to surgical drainage, about 20% of women infected by MRSA who initially underwent aspiration subsequently require surgical drainage. This study is conducted to determine the link between aetiology, antimicrobial resistance pattern and treatment modalities of breast abscesses. METHODS: Retrospective study of reviewing microbiology specimens of breast abscess patients treated at Universiti Malaya Medical Centre from 2015 to 2020. Data collected from microbiology database and electronic medical records were analysed using SPSS V21. RESULT: A total of 210 specimens from 153 patients were analysed. One-fifth (19.5%) of the specimens isolated were MDRO. Lactational associated infections had the largest proportion of MDR in comparison to non-lactational and secondary infections (38.5%, 21.7%, 25.7%, respectively; p = 0.23). Staphylococcus epidermidis recorded the highest number of MDR (n = 12) followed by S. aureus (n = 8). Adjusted by aetiological groups, the presence of MDRO is linked to failure of single aspirations (p = 0.554) and significantly doubled the risk of undergoing surgical drainage for resolution (p = 0.041). CONCLUSION: MDR in breast abscess should be recognised as an increasing healthcare burden due to a paradigm shift of MDRO and a rise of resistance cases among lactational associated infection that were vulnerable to undergo surgical incision and drainage for resolution.

Data set on the diversity and core members of bacterial community associated with two specialist fruit flies Bactrocera melastomatos and B. umbrosa (Insecta, Tephritidae).

Bactrocera melastomatos Drew & Hancock and Bactrocera umbrosa (Fabricius) are fruit flies of the subfamily Dacinae under the family Tephritidae [1]. B. melastomatos occurs in India (Andaman Island), Thailand, Peninsular Malaysia, Singapore, and Indonesia (Sumatra, Kalimantan, Java) [1] while B. umbrosa is distributed from southern Thailand and Malaysia to New Guinea and New Caledonia [2]. The adult male flies of B. melastomatos are attracted to Cue lure while the adult male flies of B. umbrosa are attracted to methyl eugenol [3]. Fruit flies of Bactrocera melastomatos infest Melastomataceae while those of B. umbrosa infest Moraceae. We compare the diversity of microbiota associated with the wild adult males of these two specialist fruit flies infesting different families of host plants. Targeted 16S rRNA gene (V3-V4 region) was sequenced using the Illumina MiSeq platform. Six bacterial phyla (Actinobacteria, Armatimonadetes, Bacteroidetes, Cyanobacteria/Melainabacteria group, Firmicutes, Proteobacteria) were detected at 97% similarity clustering and 0.001% abundance filtering. Four phyla (Actinobacteria, Bacteroidetes, Firmicutes, Proteobacteria) were present in all the specimens studied. Proteobacteria was the predominant phylum in both B. melastomatos and B. umbrosa. Enterobacteriaceae was the predominant family in UM B. melastomatos and B. umbrosa, and Orbaceae was the predominant family in Awana B. melastomatos. Klebsiella was the predominant genus in B. umbrosa, Citrobacter in UM B. melastomatos, and Orbus in Awana B. melastomatos. Double Wolbachia infections were present in UM B. melastomatos. In general, the bacterial diversity and richness varied within and between the samples of B. melastomatos and B. umbrosa.

Transcriptomic analysis reveals distinct mechanisms of adaptation of a polar picophytoplankter under ocean acidification conditions.

Human emissions of carbon dioxide are causing irreversible changes in our oceans and impacting marine phytoplankton, including a group of small green algae known as picochlorophytes. Picochlorophytes grown in natural phytoplankton communities under future predicted levels of carbon dioxide have been demonstrated to thrive, along with redistribution of the cellular metabolome that enhances growth rate and photosynthesis. Here, using next-generation sequencing technology, we measured levels of transcripts in a picochlorophyte Chlorella, isolated from the sub-Antarctic and acclimated under high and current ambient CO2 levels, to better understand the molecular mechanisms involved with its ability to acclimate to elevated CO2. Compared to other phytoplankton taxa that induce broad transcriptomic responses involving multiple parts of their cellular metabolism, the changes observed in Chlorella focused on activating gene regulation involved in different sets of pathways such as light harvesting complex binding proteins, amino acid synthesis and RNA modification, while carbon metabolism was largely unaffected. Triggering a specific set of genes could be a unique strategy of small green phytoplankton under high CO2 in polar oceans.

Novel PCR-Based Multiplex Assays for Detecting Major Quality and Biotic Stress in Commercial and Weedy Rice.

While previous research has demonstrated that multiplex polymerase chain reaction (PCR) can be a cost-effective approach to detect various genes in crops, the availability of multiplex assays to simultaneously screen both grain quality and biotic stress resistance traits in rice (Oryza sativa) is limited. In this work, we report six novel multiplex assays that use a universal protocol to detect major rice grain quality (amylose content and fragrance) and biotic stress (blast, sheath blight, and bacterial leaf blight) traits with amplified products consisting of up to four primer pairs that can be analyzed using a standard agarose-based gel electrophoresis system. Recent studies have suggested that weedy rice has novel sources of disease resistance. However, an intensive screening of weedy biotypes has not been reported in Malaysia. Accordingly, we employed one of the developed multiplex assays to screen reported genes or quantitative trait loci (QTLs) associated with blast, sheath blight, and bacterial leaf blight diseases in 100 weedy rice biotypes collected from five local fields, with phenotyping performed to validate the genotyping results. In conclusion, our universal multiplex protocol is effective for the large-scale genotyping of rice genetic resources, and it can be employed in routine molecular laboratories with limited resources.

Marine Autotroph-Herbivore Synergies: Unravelling the Roles of Macroalgae in Marine Ecosystem Dynamics.

Species invasion is a leading threat to marine ecosystems worldwide, being deemed as one of the ultimate jeopardies for biodiversity along with climate change. Tackling the emerging biodiversity threat to maintain the ecological balance of the largest biome in the world has now become a pivotal part of the Sustainable Development Goals (SDGs). Marine herbivores are often considered as biological agents that control the spread of invasive species, and their effectiveness depends largely on factors that influence their feeding preferences, including the specific attributes of their food-the autotrophs. While the marine autotroph-herbivore interactions have been substantially discussed globally, many studies have reported contradictory findings on the effects of nutritional attributes and novelty of autotrophs on herbivore feeding behaviour. In view of the scattered literature on the mechanistic basis of autotroph-herbivore interactions, we generate a comprehensive review to furnish insights into critical knowledge gaps about the synergies based largely on the characteristics of macroalgae; an important group of photosynthetic organisms in the marine biome that interact strongly with generalist herbivores. We also discuss the key defence strategies of these macroalgae against the herbivores, highlighting their unique attributes and plausible roles in keeping the marine ecosystems intact. Overall, the feeding behaviour of herbivores can be affected by the nutritional attributes, morphology, and novelty of the autotrophs. We recommend that future research should carefully consider different factors that can potentially affect the dynamics of the marine autotroph-herbivore interactions to resolve the inconsistent results of specific attributes and novelty of the organisms involved.

Kappaphycus Alvarezii Compound Powder Prevents Chemotherapy-Induced Intestinal Mucositis in BALB/c Mice.

This study aimed to formulate Kappaphycus alvarezii compound powder containing Kappaphycus alvarezii powder (KP), cooked sorghum powder (SP), and longan powder (LP); which was evaluated for its therapeutic effects against chemotherapy-induced intestinal mucosal injury (CIMI). Based on rheological properties, sensory evaluation, and antioxidant activity and using single factor and response surface methodology, the optimal formula to develop the compound powder was determined to be 35% KP, 30% SP, 5% LP, and 30% xylitol. Thereafter, the efficacy of the compound powder was tested by feeding BALB/c mice with diets supplemented with the Kappaphycus alvarezii compound powder (3% and 5%) for 14 consecutive days. The chemotherapeutic drug 5-fluorouracil was intraperitoneally injected (50 mg/kg) in the mice to induce CIMI for the last three consecutive days. Compared to the CIMI mice, those fed 5% Kappaphycus alvarezii compound powder (HC) showed significantly improved the intestinal injury, increased mucin-2 secretion, and reduced TNF-α, IL-1ß, IL-6, LT, and COX-2 levels. Furthermore, HC intake significantly reduced the Firmicutes-to-Bacteroidetes ratio, promoted the growth of beneficial bacteria, such as Alloprevotella, and inhibited the growth of harmful bacteria, such as Clostridium. In conclusion, HC has a protective effect against CIMI and provides a novel dietary strategy for patients undergoing chemotherapy.

A Meta-Analysis of the Characterisations of Plastic Ingested by Fish Globally.

Plastic contamination in the environment is common but the characterisation of plastic ingested by fish in different environments is lacking. Hence, a meta-analysis was conducted to identify the prevalence of plastic ingested by fish globally. Based on a qualitative analysis of plastic size, it was determined that small microplastics (<1 mm) are predominantly ingested by fish globally. Furthermore, our meta-analysis revealed that plastic fibres (70.6%) and fragments (19.3%) were the most prevalent plastic components ingested by fish, while blue (24.2%) and black (18.0%) coloured plastic were the most abundant. Polyethylene (15.7%) and polyester (11.6%) were the most abundant polymers. Mixed-effect models were employed to identify the effects of the moderators (sampling environment, plastic size, digestive organs examined, and sampling continents) on the prevalence of plastic shape, colour, and polymer type. Among the moderators, only the sampling environment and continent contributed to a significant difference between subgroups in plastic shape and polymer type.

Identification of curcumin as a potential α-glucosidase and dipeptidyl-peptidase 4 inhibitor: Molecular docking study, in vitro and in vivo biological evaluation.

Natural compounds have tremendous potential to regulate glucose metabolism, but conventional methods for studying their bioactivities are usually labor intensive. Here, hypoglycemic properties in 22 selected food-derived compounds were examined using molecular docking. The results indicated that curcumin is an inhibitor of both α-glucosidase and dipeptidyl-peptidase 4 (DPP-4), which are important for glycemic control. These effects of curcumin were also confirmed by enzymatic determination in vitro. Furthermore, curcumin significantly improved diet-induced hyperglycemia (e.g., fasting plasma glucose levels and glycogen storage in muscle or liver) in mice. This might be attributed to its inhibitory effects on the activities of α-glucosidase and DPP-4 in vivo. Curcumin also upregulated the expression of genes (e.g., glucagon-like peptide 1) related to DPP-4 activity in the small intestine. In conclusion, curcumin is a potential ingredient of functional foods used for diet-induced hyperglycemia management. PRACTICAL APPLICATIONS: Curcumin has been widely used as a colorant in the food industry. Moreover, a growing number of studies have described its diverse biological functions, such as anti-inflammatory, anti-oxidant, and anti-angiogenic activities. Thus, curcumin is regarded as a potential ingredient in functional foods. Our results highlighted the hyperglycemic effect of curcumin, suggesting that curcumin may be included in food products for hyperglycemic patients.

Sun-Dried and Air-Dried Kappaphycus alvarezii Attenuates 5-Fluorouracil-Induced Intestinal Mucositis in Mice.

5-fluorouracil (5-FU)-induced intestinal mucositis (IM) often makes chemotherapy patients suffer from physical and psychological suffering. Kappaphycus alvarezii (KA) is known for its potent multiple biological activities from decades. In the current study, we explored the effect of sun-dried and air-dried Kappaphycus alvarezii as a whole food supplement on 5-FU-induced IM. Diets supplemented with sun-dried Kappaphycus alvarezii (SKA, 3%), air-dried Kappaphycus alvarezii (AKA, 3%), and 5-aminosalicylic acid (0.005%) for consecutive14 days. While intraperitoneal injection of 5-FU (50 mg/kg) induced IM for last three consecutive days, and IM was assessed by the disease activity index (DAI) and inflammatory cytokine levels. Pretreatment of KA could alleviate phenotypic index, inhibit the increase of DAI, and reverse villus/crypt ratio. On the 14th day, AKA significantly increased the weight growth rate of the mice. The intervention of SKA significantly reduced the level of TNF-α and IL-1ß (P < 0.01, P < 0.01), while the intervention of AKA significantly inhibited the level of TNF-α, IL-1ß, and LT (P < 0.01, P < 0.01, P < 0.001). Therefore, these results showed that KA as a whole food supplement might be prevent the 5-FU-induced IM. For the first time suggest that the use of AKA might be more effective than SKA despite exact mechanism still needs further study.

Core members and differential abundance of chrysomelid microbiota in the life stages of Podontiaaffinis (Galerucinae) and adult Silanafarinosa(Cassidinae, Coleoptera).

The chrysomelid beetlesPodontiaaffinis and Silanafarinosa are members of the subfamilies Galerucinae and Cassidinae, respectively. This study, based on 16S rRNA gene-targeted metagenomics sequencing, reports the core members and differential abundance of bacterial communities in the larvae and adult beetles of P.affinis and the adult S.farinosa. Cyanobacteria/Melainabacteria group was the predominant phylum in the larvae of P.affinis, while Proteobacteria was the predominant phylum in adult P.affinis and S.farinosa. The number of Order, Family, Genus and Species OTUs in the adult stage of P.affinis was higher than that in the larval stage. The bacterial species richness of adult P.affinis was significantly higher than that of adult S.farinosa. Betaproteobacteria was the predominant class in adult P.affinis, Cyanobacteria in the larvae of P.affinis and Gammaproteobacteria in S.farinosa. The larvae and adult beetles of P.affinis and adult S.farinosahad a low number of unique and shared bacterial OTUs (> 5% relative abundance). The differences in the microbiota indicate possible differences in nutrient assimilation, host taxonomy and other stochastic processes. These findings provide new information to our understanding of the bacteria associated with specialist phytophagous chrysomelid beetles and beetles in general.

Complete mitochondrial genomes and phylogenetic relationships of the genera Nephila and Trichonephila (Araneae, Araneoidea).

Spiders of the genera Nephila and Trichonephila are large orb-weaving spiders. In view of the lack of study on the mitogenome of these genera, and the conflicting systematic status, we sequenced (by next generation sequencing) and annotated the complete mitogenomes of N. pilipes, T. antipodiana and T. vitiana (previously N. vitiana) to determine their features and phylogenetic relationship. Most of the tRNAs have aberrant clover-leaf secondary structure. Based on 13 protein-coding genes (PCGs) and 15 mitochondrial genes (13 PCGs and two rRNA genes), Nephila and Trichonephila form a clade distinctly separated from the other araneid subfamilies/genera. T. antipodiana forms a lineage with T. vitiana in the subclade containing also T. clavata, while N. pilipes forms a sister clade to Trichonephila. The taxon vitiana is therefore a member of the genus Trichonephila and not Nephila as currently recognized. Studies on the mitogenomes of other Nephila and Trichonephila species and related taxa are needed to provide a potentially more robust phylogeny and systematics.

Impact of elevated temperature on the physiological and biochemical responses of Kappaphycus alvarezii (Rhodophyta).

The eucheumatoids Kappaphycus and Eucheuma are cultivated in tropical or subtropical regions for the production of carrageenan, a hydrocolloid widely used in the food and cosmetic industries. Kappaphycus alvarezii is a highly valued economic crop in the Coral Triangle, with the Philippines, Indonesia and Malaysia ranked among the largest producers. In the absence of measures to mitigate climate change, extreme events including heatwaves, typhoons, severe El Niño and La Niña, are expected to increase in frequency and magnitude. This inadvertently brings adverse effects to the seaweed cultivation industry, especially in the tropics. Temperatures are rapidly reaching the upper limit of biologically tolerable levels and an increase in reports of ice-ice and pest outbreaks is attributable to these shifts of environmental parameters. Nevertheless, few reports on the response of eucheumatoids to a changing environment, in particular global warming, are available. Understanding the responses and possible mechanisms for acclimation to warming is crucial for a sustainable seaweed cultivation industry. Here, the physiological and biochemical responses of K. alvarezii to acute warming indicated that the strain used in the current study is unlikely to survive sudden increases in temperature above 36°C. As temperature increased, the growth rates, photosynthetic performance, phycocolloid quality (carrageenan yield, gel strength and gel viscosity) and pigment content (chlorophyll-a, carotenoid and phycobiliproteins) were reduced while the production of reactive oxygen species increased indicating the occurrence of stress in the seaweeds. This study provides a basis for future work on long term acclimation to elevated temperature and mesocosm-based multivariate studies to identify heat-tolerant strains for sustainable cultivation.

The 21st Century Agriculture: When Rice Research Draws Attention to Climate Variability and How Weedy Rice and Underutilized Grains Come in Handy.

Rice, the first crop to be fully sequenced and annotated in the mid-2000s, is an excellent model species for crop research due mainly to its relatively small genome and rich genetic diversity. The 130-million-year-old cereal came into the limelight in the 1960s when the semi-dwarfing gene sd-1, better known as the "green revolution" gene, resulted in the establishment of a high-yielding semi-dwarf variety IR8. Deemed as the miracle rice, IR8 saved millions of lives and revolutionized irrigated rice farming particularly in the tropics. The technology, however, spurred some unintended negative consequences, especially in prompting ubiquitous monoculture systems that increase agricultural vulnerability to extreme weather events and climate variability. One feasible way to incorporate resilience in modern rice varieties with narrow genetic backgrounds is by introgressing alleles from the germplasm of its weedy and wild relatives, or perhaps from the suitable underutilized species that harbor novel genes responsive to various biotic and abiotic stresses. This review reminisces the fascinating half-century journey of rice research and highlights the potential utilization of weedy rice and underutilized grains in modern breeding programs. Other possible alternatives to improve the sustainability of crop production systems in a changing climate are also discussed.

Genetic diversity and population structure of Terapon jarbua (Forskål, 1775) (Teleostei, Terapontidae) in Malaysian waters.

A background study is important for the conservation and stock management of a species. Terapon jarbua is a coastal Indo-Pacific species, sourced for human consumption. This study examined 134 samples from the central west and east coasts of Peninsular (West) Malaysia and East Malaysia. A 1446-bp concatenated dataset of mtDNA COI and Cyt b sequences was used in this study and 83 haplotypes were identified, of which 79 are unique haplotypes and four are shared haplotypes. Populations of T. jarbua in Malaysia are genetically heterogenous as shown by the high level of haplotype diversity ranging from 0.9167-0.9952, low nucleotide diversity ranging from 0.0288-0.3434, and high FST values (within population genetic variation). Population genetic structuring is not distinct as shown by the shared haplotypes between geographic populations and mixtures of haplotypes from different populations within the same genetic cluster. The gene flow patterns and population structuring observed among these regions are likely attributed to geographical distance, past historical events, allopatric speciation, dispersal ability and water currents. For instance, the mixture of haplotypes revealed an extraordinary migration ability of T. jarbua (>1200 km) via ancient river connectivity. The negative overall value of the neutrality test and a non-significant mismatch distribution are consistent with demographic expansion(s) in the past. The median-joining network concurred with the maximum likelihood haplotype tree with three major clades resolved. The scarcity of information on this species is an obstacle for future management and conservation purposes. Hence, this study aims to contribute information on the population structure, genetic diversity, and historical demography of T. jarbua in Malaysia.

Native κ-carrageenan induced-colitis is related to host intestinal microecology.

Inflammatory bowel disease (IBD), including Crohn's disease and ulcerative colitis, has gradually emerged as a public health challenge worldwide. Carrageenan is a popular food additive that has been in use for decades. However, controversy exists regarding to the safety of carrageenan due to its exacerbation of colitis in experimental models. In this study, we studied the effects of vehicle and host intestinal microflora on carrageenan inflammatory properties in C57BL/6 J mice. We found that in high-fat diet model, native carrageenan in drinking water increased the disease activity index (DAI), myeloperoxidase (MPO) activity and the mRNA expression of TLR4 in colon, whereas carrageenan-supplemented diet has no visible effects. However, no signs of colitis were observed under low-fat diet regardless of the mode of vehicle used. Moreover, we discovered that carrageenan-induced colitis in high-fat diet model was robustly correlated with changes in the composition of gut microbiota, specifically Alistipes finegoldii and Bacteroides acidifaciens. Hence, we propose that the inflammatory property of carrageenan is influenced greatly by its intake form via modification of host intestinal microecology.

Enhanced coproduction of astaxanthin and lipids by the green microalga Chromochloris zofingiensis: Selected phytohormones as positive stimulators.

Phytohormones comprise a variety of trace bioactive compounds that can stimulate cell growth and promote metabolic shifts. In the present work, a two-stage screening strategy was innovatively established to identify positive phytohormones for enhancement of astaxanthin and lipid coproduction in microplate-based cultures of mixotrophic Chromochloris zofingiensis. The results showed that auxins were the most efficient stimulators for astaxanthin accumulation. The maximum content of 13.1 mg/g and yield of 89.9 mg/L were obtained using indole propionic acid (10 mg/L) and indoleacetic acid (7.8 mg/L), representing the highest levels of astaxanthin in this microalga reported to date. Total lipids with the highest content (64.5% DW) and productivity (445.7 mg/L/d) were coproduced with astaxanthin using indoleacetic acid. Statistical analysis revealed close relations between phytohormones and astaxanthin and lipid biosynthesis. This study provides a novel original strategy for improving astaxanthin and lipid coproduction in C. zofingiensis using the selected phytohormones as positive stimulators.

A metabolomic approach to investigate effects of ocean acidification on a polar microalga Chlorella sp.

Ocean acidification, due to increased levels of anthropogenic carbon dioxide, is known to affect the physiology and growth of marine phytoplankton, especially in polar regions. However, the effect of acidification or carbonation on cellular metabolism in polar marine phytoplankton still remains an open question. There is some evidence that small chlorophytes may benefit more than other taxa of phytoplankton. To understand further how green polar picoplankton could acclimate to high oceanic CO2, studies were conducted on an Antarctic Chlorella sp. Chlorella sp. maintained its growth rate (∼0.180 d-1), photosynthetic quantum yield (Fv/Fm = ∼0.69) and chlorophyll a (0.145 fg cell-1) and carotenoid (0.06 fg cell-1) contents under high CO2, while maximum rates of electron transport decreased and non-photochemical quenching increased under elevated CO2. GCMS-based metabolomic analysis reveal that this polar Chlorella strain modulated the levels of metabolites associated with energy, amino acid, fatty acid and carbohydrate production, which could favour its survival in an increasingly acidified ocean.

Elevated CO2 improves both lipid accumulation and growth rate in the glucose-6-phosphate dehydrogenase engineered Phaeodactylum tricornutum.

BACKGROUND: Numerous studies have shown that stress induction and genetic engineering can effectively increase lipid accumulation, but lead to a decrease of growth in the majority of microalgae. We previously found that elevated CO2 concentration increased lipid productivity as well as growth in Phaeodactylum tricornutum, along with an enhancement of the oxidative pentose phosphate pathway (OPPP) activity. The purpose of this work directed toward the verification of the critical role of glucose-6-phosphate dehydrogenase (G6PDH), the rate-limiting enzyme in the OPPP, in lipid accumulation in P. tricornutum and its simultaneous rapid growth rate under high-CO2 (0.15%) cultivation. RESULTS: In this study, G6PDH was identified as a target for algal strain improvement, wherein G6PDH gene was successfully overexpressed and antisense knockdown in P. tricornutum, and systematic comparisons of the photosynthesis performance, algal growth, lipid content, fatty acid profiles, NADPH production, G6PDH activity and transcriptional abundance were performed. The results showed that, due to the enhanced G6PDH activity, transcriptional abundance and NAPDH production, overexpression of G6PDH accompanied by high-CO2 cultivation resulted in a much higher of both lipid content and growth in P. tricornutum, while knockdown of G6PDH greatly decreased algal growth as well as lipid accumulation. In addition, the total proportions of saturated and unsaturated fatty acid, especially the polyunsaturated fatty acid eicosapentaenoic acid (EPA; C20:5, n-3), were highly increased in high-CO2 cultivated G6PDH overexpressed strains. CONCLUSIONS: The successful of overexpression and antisense knockdown of G6PDH well demonstrated the positive influence of G6PDH on algal growth and lipid accumulation in P. tricornutum. The improvement of algal growth, lipid content as well as polyunsaturated fatty acids in high-CO2 cultivated G6PDH overexpressed P. tricornutum suggested this G6PDH overexpression-high CO2 cultivation pattern provides an efficient and economical route for algal strain improvement to develop algal-based biodiesel production.

Physiological and metabolic responses of Scenedesmus quadricauda (Chlorophyceae) to nickel toxicity and warming.

An ecologically important tropical freshwater microalga, Scenedesmus quadricauda, was exposed to Ni toxicity under two temperature regimes, 25 and 35 °C to investigate the interactive effects of warming and different Ni concentrations (0.1, 1.0 and 10.0 ppm). The stress responses were assessed from the growth, photosynthesis, reactive oxygen species (ROS) generation and metabolomics aspects to understand the effects at both the physiological and biochemical levels. The results showed that the cell densities of the cultures were higher at 35 °C compared to 25 °C, but decreased with increasing Ni concentrations at 35 °C. In terms of photosynthetic efficiency, the maximum quantum yield of photosystem II (F v/F m) of S. quadricauda remained consistent across different conditions. Nickel concentration at 10.0 ppm affected the maximum rate of relative electron transport (rETRm) and saturation irradiance for electron transport (E k) in photosynthesis. At 25 °C, the increase of non-photochemical quenching (NPQ) values in cells exposed to 10.0 ppm Ni might indicate the onset of thermal dissipation process as a self-protection mechanism against Ni toxicity. The combination of warming and Ni toxicity induced a strong oxidative stress response in the cells. The ROS level increased significantly by 40% after exposure to 10.0 ppm of Ni at 35 °C. The amount of Ni accumulated in the biomass was higher at 25 °C compared to 35 °C. Based on the metabolic profile, temperature contributed the most significant differentiation among the samples compared to Ni treatment and the interaction between the two factors. Amino acids, sugars and organic acids were significantly regulated by the combined factors to restore homeostasis. The most affected pathways include sulphur, amino acids, and nitrogen metabolisms. Overall, the results suggest that the inhibitory effect of Ni was lower at 35 °C compared to 25 °C probably due to lower metal uptake and primary metabolism restructuring. The ability of S. quadricauda to accumulate substantial amount of Ni and thrive at 35 °C suggests the potential use of this strain for phycoremediation and outdoor wastewater treatment.