Phytochemical Profiles and Biological Activities of Five Wild Camellia Species from Ta Dung, Vietnam.

The C. luuana (TD3), C. furfuracea (TD4), C. bidoupensis (TD6), C. sinensis (L.) (TD7), and C. kissii (TD8), have been traditionally used as a health-promoting beverage by local people in Ta Dung, Dak Nong. Despite their potential health benefits, further scientific data on biological and phytochemical properties of these plants is needed. This study aimed to investigate phytochemical and biological properties of five Camellia species extracts, using DPPH, ABTS radical scavenging, copper chelating (Cu-chelator), and tyrosinase inhibition (TI), α-amylase (Al-AI), and α-glucosidase (Al-GI) analyses. Ten compounds were identified using UPLC method, in which catechins (mainly EGCG and catechin (Cat)), were the most prevalent, and followed by chlorogenic acid (ChlA), quercitrin (Querci), rutin, and quercetin (Querce). Multiple factor analysis (MFA) also revealed that TD7, TD3, and TD4 containing high TPC, TFC, EGCG, ChlA, and caffeine were responsible for their high DPPH, ABTS radical scavenging activities and TI, Al-AI and Al-GI. TD6 and TD8, possessing elevated levels of Apig, Querce, Rutin, Querce, Cat, and EA, exhibited a high Cu-chelator property, but a weak enzyme inhibition. From all above-mentioned results, the antioxidative and enzyme inhibitory potentials of Camellia species extracts were scientifically demonstrated paving a pathway to develop health supplement in further studies.

Fostering the Job Performance of Nurses: A Responsibility of an Ethical Hospital.

Introduction: Corporate social responsibility (CSR) practices refer to the deliberate actions and strategies implemented by a company or organization to generate positive outcomes for its stakeholders beyond the sole objective of profit maximization. Internal CSR is a significant management and investment concept within enterprises, such as hospitals, that enhances organizational performance excellence. Objectives: The article aims to trace how hospitals thrive in nurses' job performance by leveraging internal CSR practices. Methods: Cross-sectional design quantitative research through structured questionnaire interviews on 215 nurses in Vietnam. Data collection was conducted from May 2023 to August 2023. Partial least squares structural equation modeling was applied to test the hypotheses. Results: The study has proven that a hospital's internal CSR practices impact nurses' job performance. Income and benefits, human resource training and development, and work-related quality of life directly and significantly impact three dimensions of a nurse's job performance (competence to practice patient care, attitude to performance work, and management and professional development capacity). Connection and trust in the workplace and health and safety at work significantly affect two dimensions of a nurse's job performance (namely, competence to practice patient care and attitude to performance work). Diversity in the workplace impacts nurses' competence in practicing patient care and their management and professional development capacity. Demographic variables did not correlate statistically significantly with dimensions of internal CSR and nurses' job performance. Conclusion: The study presents significant findings on the influence of internal CSR on nurses' job performance within the hospital management theory of an emerging market. The results of the present study contribute to a better understanding of the benefits of hospitals' socially responsible actions and contribute further to resource management in hospitals, especially nursing. If the nursing staff positively perceives the hospital's internal CSR practices, they will be more able to perform their job, impacting the hospital's overall performance. This study has certain limitations regarding the representative nature of the sample, the use of the self-report survey instrument, and the use of cross-sectional data.

Vitamin Solutions Effects on Reproduction of Broodstock, Growth Performance, and Survival Rate of Pangasius Catfish Fingerlings.

This study evaluates the effect of different diets supplemented with vitamin solutions on Pangasius catfish broodstock reproduction, growth performances, and the survival rates of fish larvae and fingerling. The growth and reproductive performances of breeders fed with different test diets showed significant differences among the six tested diets (p < 0.05). The highest final body weight (FBW), weight gain (WG), daily weight gain (DWG), specific growth rate (SGR) of broodstock, and survival rate of Pangasius fingerlings were found in Treatment 5, which contained 0.6% H-OVN mixed with 12.6% algal oil, and Treatment 3, which contained 0.6% vitamin premix H-OVN. The average gonadosomatic index (GSI), relative fecundity index (RFI), fertilized eggs, hatching rates of eggs, and survival rate of fingerlings was 9.1 ± 2.8 (6.7-12.8%), 133,224 ± 39,090 (104,267-199,512 eggs/kg), 77.9 ± 22.2 (62.2-93.6%), and 45.3 ± 17.4 (22.0-66.3%), respectively. The findings of this study showed that the diet containing 35% CP contents supplemented with 0.6% vitamin premix H-OVN mixed with algal oils showed the highest results in terms of growth, reproductive performance indices, and survival rates of Pangasius catfish fingerlings.

Rare complications of chronic cholangitis: Pseudoaneurysm of the hepatic artery causing serious gastrointestinal bleeding.

Gastrointestinal bleeding due to hemobilia is a rare condition but can be very serious, even life-threatening. The main causes of biliary bleeding are invasive procedures in treatment, trauma, or malignant diseases. Chronic obstruction of the biliary tract can cause inflammation, erosion, and leakage of adjacent vascular structures and lead to pseudoaneurysm or hemorrhage, but this is very rare. In this article, we present a clinical case of upper gastrointestinal bleeding due to a pseudoaneurysm of the hepatic artery believed to have formed due to chronic cholangitis. An 81-year-old female patient with a medical history of chronic cholangitis was admitted to the hospital with recurrent inflammation accompanied by progressive upper gastrointestinal bleeding, potentially life-threatening. Ultrasound images and blood tests confirmed that the patient had anemia and cholangitis caused by stones. Gastrointestinal endoscopy showed bleeding suspected to be from the biliary tract. Hepatobiliary computed tomography confirmed that the common hepatic artery pseudoaneurysm located at the upper end of the common bile duct had active bleeding.

Effects of cutting tool geometry on material removal of a gradient nanograined CoCrNi medium entropy alloy.

CoCrNi medium-entropy alloys (MEAs) have attracted extensive attention and research because of their superior mechanical properties, such as higher ductility, strength, and toughness. This study uses molecular dynamics (MD) simulations to investigate the cutting behavior of a gradient nanograined (GNG) CoCrNi MEA. Moreover, it explores the influence of relative tool sharpness and rake angle on the cutting process. The results show that an increase in the average grain size of the GNG samples leads to a decrease in the average resultant cutting force, as predicted by the Hall-Petch relationship. The deformation behavior shows that grain boundaries are crucial in inhibiting the propagation of strain and stress. As the average grain size of the GNG sample increases, the range of shear strain distribution and average von Mises stress decreases. Moreover, the cutting chips become thinner and longer. The subsurface damage is limited to a shallow layer at the surface. Since thermal energy is generated in the high grain boundary density, the temperature of the contact zone between the substrate and the cutting tool increases as the GNG size decreases. The cutting chips removed from the GNG CoCrNi MEA substrates will transform into a mixed structure of face-centered cubic and hexagonally close-packed phases. The sliding and twisting of grain boundaries and the merging of grains are essential mechanisms for polycrystalline deformation. Regarding the cutting parameters, the average resultant force, the material accumulation, and the chip volume increase significantly with the increase in cutting depth. In contrast to sharp tools, which mainly use shear deformation, blunt tools remove material by plowing, and the cutting force increases with the increase in cutting-edge radius and negative rake angle.

Evaluation of Selective Culling as a Containment Strategy for African Swine Fever at a Vietnamese Sow Farm.

Selective culling, also known as the "tooth extraction approach", is a strategy for controlling African swine fever (ASF) by removing only sick and suspect animals instead of the entire herd in Vietnam. This method prioritizes preserving healthy animals, particularly valuable breeding pigs. Despite its implementation in various forms, no standardized protocol based on scientific principles has been established. Farms typically adapt this strategy based on their understanding, which can vary significantly. In implementing of selective culling that is not based on scientific principles, there is a significant risk of spreading the disease. The aim of this study is to evaluate the consequences of selective culling as currently implemented in Vietnam. Our analysis on a large sow farm revealed that current practices rely heavily on clinical observations without laboratory confirmations. This approach allows ASF-infected animals to remain on the farm longer, potentially exacerbating the spread of the virus. Thus, selective culling poses a substantial risk by potentially exacerbating the spread of disease. Our findings emphasize that early diagnosis of ASF and systematic removal of infected pigs are critical components for the effective implementation of selective culling strategies and that a high level of fragmentation to minimize contact between animals plays a key role. The optimal approach is to test conspicuous animals and separate them. Under no circumstances should suspect animals be left in the herd for several days before they become severely ill and succumb to the disease.

A case of giant labia majora lipoma in an adult.

Lipomas are common benign adipose tissue tumors but are infrequently found in the labia majora, especially at a large size. We report a case of a giant lipoma of the labia majora in a 37-year-old woman diagnosed by imaging methods and successfully treated by surgery. This case highlights the importance of considering lipoma in the differential diagnosis of labial masses and underscores the role of imaging in diagnosis. They need to be differentiated from liposarcoma or omental herniation into Nuck's canal. It also demonstrates the effectiveness of surgical management for large lipomas in sensitive areas, with attention to both medical and aesthetic outcomes.

The Human Microbiome as a Therapeutic Target for Metabolic Diseases.

The human microbiome functions as a separate organ in a symbiotic relationship with the host. Disruption of this host-microbe symbiosis can lead to serious health problems. Modifications to the composition and function of the microbiome have been linked to changes in host metabolic outcomes. Industrial lifestyles with high consumption of processed foods, alcoholic beverages and antibiotic use have significantly altered the gut microbiome in unfavorable ways. Therefore, understanding the causal relationship between the human microbiome and host metabolism will provide important insights into how we can better intervene in metabolic health. In this review, I will discuss the potential use of the human microbiome as a therapeutic target to improve host metabolism.

Assessment of the level and risk of radioactive hazards in coastal sediments in northern Vietnam.

Radioactivity in coastal sediments in northern Vietnam was examined using data from five sediment cores to assess radioactivity concentrations and radiation risk indices. Radiation risk indices included radium equivalent activity (Raeq), the absorbed dose rate (ADR), the annual effective dose equivalent (AEDE), the activity utilization index (AUI), the external hazard index (Hex), the representative level gamma index (Iγr), and the annual gonadal effective dose rate (AGDE). The radioactivity concentrations of 40K, 232Th, 226Ra, 238U, and 137Cs were 567, 56.1, 35.1, 37.9, and 1.18 Bq/kg, respectively. The average concentrations of 40K, 232Th, 226Ra, and 238U were above the global average at five sites, except for 137Cs, which was low. The Raeq, Hex, and AUI indices were below the recommended values, while the AEDE, ADR, AGDE, and Iγr indices were above the recommended values. Moreover, 40K, 232Th, 226Ra, and 238U had significant impacts on the radiation hazard indices Raeq, ADR, AEDE, Iγr, AUI, Hex, and AGDE. There are three coastal sediment groups on the northern coast of Vietnam: Group 1 has a higher radioactivity and radiation risk index than Group 2 but a lower value than Group 3. Group 3 had the highest radioactivity and radiation risk index. The values of 40K, 232Th, 226Ra, and 238U and the ADR, AUI, Iγr, and AGDE indices in the sediment threaten the living environment.

Production, Purification, and Characterization of a Cellulase from Paenibacillus elgii.

Cellulases are one of the most essential natural factors for cellulose degradation and, thus, have attracted significant interest for various applications. In this study, a cellulase from Paenibacillus elgii TKU051 was produced, purified, and characterized. The ideal fermentation conditions for cellulase productivity were 2% carboxymethyl cellulose (CMC) as the growth substrate, pH = 8, temperature of 31 °C, and 4 days of culturing. Accordingly, a 45 kDa cellulase (PeCel) was successfully purified in a single step using a High Q column with a recovery yield of 35% and purification of 42.2-fold. PeCel has an optimal activity at pH 6 and a temperature of 60 °C. The activity of cellulase was significantly inhibited by Cu2+ and enhanced by Mn2+. The PeCel-catalyzed products of the CMC hydrolysis were analyzed by high-performance liquid chromatography, which revealed chitobiose and chitotriose as the major products. Finally, the clarity of apple juice was enhanced when treated with PeCel.

Effective Management of Severe Amlodipine/Atenolol Overdose with Intravenous Calcium, Hyperinsulinemic Euglycemia Therapy, and Continuous Veno-Venous Hemodialysis: A Case Report.

BACKGROUND Amlodipine, a calcium channel blocker, and atenolol, a beta blocker, are commonly used as a fixed drug combination (FDC) to treat hypertension. Intentional or non-intentional overdose of amlodipine-atenolol results in hypotension and myocardial depression with a high risk of mortality. This report describes a 64-year-old man with an overdose of amlodipine-atenolol, presenting as an emergency with hypotension, bradycardia, and severe metabolic acidosis. He was successfully treated with intravenous calcium chloride infusion, hyperinsulinemia euglycemia therapy (HIE), and continuous veno-venous hemodialysis (CVVHD). CASE REPORT A 64-year-old man was diagnosed with essential hypertension 1 week prior to the admission. He had been prescribed 1 FDC tablet of amlodipine and atenolol (5+50 mg) per day; however, he took 1 table of the FDC per day for 3 days and then took 3-4 tablets each day during the next 4 days. He was brought to the hospital with hypotension, bradycardia, and severe metabolic acidosis and was diagnosed with amlodipine-atenolol overdose. He was treated with intravenous calcium chloride infusion, HIE, and CVVHD. His hemodynamics started to improve after administering these therapies for 6 h. Inotropes were gradually tapered off and stopped. He was extubated on day 5 and recovered completely. CONCLUSIONS This report shows the serious effects amlodipine-atenolol overdose and the challenges of emergency patient management. An overdose of FDC of amlodipine and atenolol can cause cardiovascular collapse and severe metabolic acidosis. Timely and aggressive management with intravenous calcium infusion, HIE, and CVVHD is essential.

Evaluation of Dihydroartemisinin-Piperaquine Efficacy and Molecular Markers in Uncomplicated Falciparum Patients: A Study across Binh Phuoc and Dak Nong, Vietnam.

Background and Objectives: Malaria continues to be a significant global health challenge. The efficacy of artemisinin-based combination therapies (ACTs) has declined in many parts of the Greater Mekong Subregion, including Vietnam, due to the spread of resistant malaria strains. This study was conducted to assess the efficacy of the Dihydroartemisinin (DHA)-Piperaquine (PPQ) regimen in treating uncomplicated falciparum malaria and to conduct molecular surveillance of antimalarial drug resistance in Binh Phuoc and Dak Nong provinces. Materials and Methods: The study included 63 uncomplicated malaria falciparum patients from therapeutic efficacy studies (TES) treated following the WHO treatment guidelines (2009). Molecular marker analysis was performed on all 63 patients. Methods encompassed Sanger sequencing for pfK13 mutations and quantitative real-time PCR for the pfpm2 gene. Results: This study found a marked decrease in the efficacy of the DHA-PPQ regimen, with an increased rate of treatment failures at two study sites. Genetic analysis revealed a significant presence of pfK13 mutations and pfpm2 amplifications, indicating emerging resistance to artemisinin and its partner drug. Conclusions: The effectiveness of the standard DHA-PPQ regimen has sharply declined, with rising treatment failure rates. This decline necessitates a review and possible revision of national malaria treatment guidelines. Importantly, molecular monitoring and clinical efficacy assessments together provide a robust framework for understanding and addressing detection drug resistance in malaria.

Daily oral administration of probiotics engineered to constantly secrete short-chain fatty acids effectively prevents myocardial injury from subsequent ischemic heart disease.

AIM: Given the extremely limited regeneration potential of the heart, one of the most effective strategies to reduce the prevalence and mortality of coronary artery disease is prevention. Short-chain fatty acids (SCFAs), which are by-products of beneficial probiotics, have been reported to possess cardioprotective effects. Despite their beneficial roles, delivering SCFAs and maintaining their effective concentration in plasma present major challenges. Therefore, in the present study, we aimed to devise a strategy to prevent coronary heart disease effectively by using engineered probiotics to continuously release SCFAs in vivo. METHODS AND RESULTS: We engineered a novel probiotic cocktail, EcN_TL, from the commercially available Escherichia coli Nissle 1917 strain to continuously secrete SCFAs by introducing the propionate and butyrate biosynthetic pathways. Oral administration of EcN_TL enhanced and maintained an effective concentration of SCFAs in the plasma. As a preventative strategy, we observed that daily intake of EcN_TL for 14 days prior to ischemia-reperfusion injury significantly reduced myocardial injury and improved cardiac performance compared to EcN administration. We uncovered that EcN_TL's protective mechanisms included reducing neutrophil infiltration into the infarct site and promoting the polarization of wound-healing macrophages. We further revealed that SCFAs at plasma concentration protected cardiomyocytes from inflammation by suppressing the NF-κB activation pathway. CONCLUSIONS: These data provide strong evidence to support the use of SCFA-secreting probiotics to prevent coronary heart disease. Since SCFAs also play a key role in other metabolic diseases, EcN_TL can potentially be used to treat a variety of other diseases.

Leptospira infection in bats in Vietnam.

Bats from three provinces in Vietnam (Lai Chau, Son La, and Dong Thap) were examined for the presence of pathogenic Leptospira or specific antibodies using polymerase chain reaction (PCR), enzyme-linked immunosorbent assay (ELISA), and microscopic agglutination test (MAT). Tissue specimens from 298 bats belonging to 11 species were analyzed using a real-time PCR assay specific for leptospires of pathogenic species. Leptospiral DNA was identified in 40 bats from following species: Rousettus amplexicaudatus (5/9; 55.5 %), Rousettus leschenaultii (17/42; 40.4 %), Myotis hasseltii (8/25; 32 %), Taphozous longimanus (3/12; 25 %), and Eonycteris spelaea (7/32; 21.9 %). Based on secY phylogeny, sequences from M. hasseltii bore a strong resemblance to L. borgpetersenii. Sequences from other species revealed unique lineages: one of them resembled Leptospira sp., previously identified in Rousettus madagascariensis (Madagascar) and Rousettus aegyptiacus (South Africa); the second lineage showed close relation to L. kirshneri; and the third held an intermediary position between L. noguchii and L. interrogans. Through ELISA, anti-Leptospira antibodies were found in 83 of 306 bats, with the highest seroprevalence observed in R. leschenaultii (44/48; 91.6 %), R. amplexicaudatus (6/8; 75 %), and E. spelaea (19/25; 76 %). 66 of these ELISA-positive samples were tested using MAT; 41 of them were confirmed in MAT as positive. The predominant serogroups in our study were Tarassovi and Mini.

Characterisation of the Cinnamomumparthenoxylon (Jack) Meisn (Lauraceae) transcriptome using Illumina paired-end sequencing and EST-SSR markers development for population genetics.

Cinnamomumparthenoxylon is an endemic and endangered species with significant economic and ecological value in Vietnam. A better understanding of the genetic architecture of the species will be useful when planning management and conservation. We aimed to characterize the transcriptome of C.parthenoxylon, develop novel molecular markers, and assess the genetic variability of the species. First, transcriptome sequencing of five trees (C.parthenoxylon) based on root, leaf, and stem tissues was performed for functional annotation analysis and development of novel molecular markers. The transcriptomes of C.parthenoxylon were analyzed via an Illumina HiSeqTM 4000 sequencing system. A total of 27,363,199 bases were generated for C.parthenoxylon. De novo assembly indicated that a total of 160,435 unigenes were generated (average length = 548.954 bp). The 51,691 unigenes were compared against different databases, i.e. COG, GO, KEGG, KOG, Pfam, Swiss-Prot, and NR for functional annotation. Furthermore, a total of 12,849 EST-SSRs were identified. Of the 134 primer pairs, 54 were randomly selected for testing, with 15 successfully amplified across nine populations of C.parthenoxylon. We uncovered medium levels of genetic diversity (PIC = 0.52, Na = 3.29, Ne = 2.18, P = 94.07%, Ho = 0.56 and He = 0.47) within the studied populations. The molecular variance was 10% among populations and low genetic differentiation (Fst = 0.06) indicated low gene flow (Nm = 2.16). A reduction in the population size of C.parthenoxylon was detected using BOTTLENECK (VP population). The structure analysis suggested two optimal genetic clusters related to gene flow among the populations. Analysis of molecular variance (AMOVA) revealed higher genetic variation within populations (90%) than among populations (10%). The UPGMA approach and DAPC divided the nine populations into three main clusters. Our findings revealed a significant fraction of the transcriptome sequences and these newlydeveloped novel EST-SSR markers are a very efficient tool for germplasm evaluation, genetic diversity and molecular marker-assisted selection in C.parthenoxylon. This study provides comprehensive genetic resources for the breeding and conservation of different varieties of C.parthenoxylon.

Cellular-resolution gene expression mapping reveals organization in the head ganglia of the gastropod, Berghia stephanieae.

Gastropod molluscs such as Aplysia, Lymnaea, and Tritonia have been important for determining fundamental rules of motor control, learning, and memory because of their large, individually identifiable neurons. Yet only a small number of gastropod neurons have known molecular markers, limiting the ability to establish brain-wide structure-function relations. Here we combine high-throughput, single-cell RNA sequencing with in situ hybridization chain reaction in the nudibranch Berghia stephanieae to identify and visualize the expression of markers for cell types. Broad neuronal classes were characterized by genes associated with neurotransmitters, like acetylcholine, glutamate, serotonin, and GABA, as well as neuropeptides. These classes were subdivided by other genes including transcriptional regulators and unannotated genes. Marker genes expressed by neurons and glia formed discrete, previously unrecognized regions within and between ganglia. This study provides the foundation for understanding the fundamental cellular organization of gastropod nervous systems.

Phytate metabolism is mediated by microbial cross-feeding in the gut microbiota.

Dietary intake of phytate has various reported health benefits. Previous work showed that the gut microbiota can convert phytate to short-chain fatty acids (SCFAs), but the microbial species and metabolic pathway are unclear. Here we identified Mitsuokella jalaludinii as an efficient phytate degrader, which works synergistically with Anaerostipes rhamnosivorans to produce the SCFA propionate. Analysis of published human gut taxonomic profiles revealed that Mitsuokella spp., in particular M. jalaludinii, are prevalent in human gut microbiomes. NMR spectroscopy using 13C-isotope labelling, metabolomic and transcriptomic analyses identified a complete phytate degradation pathway in M. jalaludinii, including production of the intermediate Ins(2)P/myo-inositol. The major end product, 3-hydroxypropionate, was converted into propionate via a synergistic interaction with Anaerostipes rhamnosivorans both in vitro and in mice. Upon [13C6]phytate administration, various 13C-labelled components were detected in mouse caecum in contrast with the absence of [13C6] InsPs or [13C6]myo-inositol in plasma. Caco-2 cells incubated with co-culture supernatants exhibited improved intestinal barrier integrity. These results suggest that the microbiome plays a major role in the metabolism of this phytochemical and that its fermentation to propionate by M. jalaludinii and A. rhamnosivorans may contribute to phytate-driven health benefits.

Transfer of natural radionuclides from soil to water spinach (Ipomoea aquatica Forssk) under flooded and unflooded conditions in Hanoi, Vietnam.

Transfer of natural radionuclides from soil to water spinach (Ipomoea aquatica Forssk) in Hanoi, Vietnam have been investigated using a low background gamma spectrometer with an HPGe detector (Model-GC5019). Twenty pairs of soil and water spinach samples in two environmental conditions, i.e., flooded and unflooded, were collected for measuring the activity concentrations and determining the soil-to-plant transfer factors (TFs) of natural radionuclides. For water spinach, stems and leaves were collected as the main parts for human consumption and livestock food. The TF of 40K is within the range of 0.32-2.49, which is greater than that of 228Ra (0.01-0.17) and 226Ra (0.01-0.13). The geometric means (geometric standard deviations) of the TFs are 1.17(1.89), 0.05(2.41) and 0.04(1.88) for flooded sites, and 0.89(1.73), 0.03(2.12) and 0.03(1.82) for unflooded sites, respectively. Comparing between the flooded and unflooded sites, the TFs are all greater at the flooded sites.

The paleoredox context of early eukaryotic evolution: insights from the Tonian Mackenzie Mountains Supergroup, Canada.

Tonian (ca. 1000-720 Ma) marine environments are hypothesised to have experienced major redox changes coinciding with the evolution and diversification of multicellular eukaryotes. In particular, the earliest Tonian stratigraphic record features the colonisation of benthic habitats by multicellular macroscopic algae, which would have been powerful ecosystem engineers that contributed to the oxygenation of the oceans and the reorganisation of biogeochemical cycles. However, the paleoredox context of this expansion of macroalgal habitats in Tonian nearshore marine environments remains uncertain due to limited well-preserved fossils and stratigraphy. As such, the interdependent relationship between early complex life and ocean redox state is unclear. An assemblage of macrofossils including the chlorophyte macroalga Archaeochaeta guncho was recently discovered in the lower Mackenzie Mountains Supergroup in Yukon (Canada), which archives marine sedimentation from ca. 950-775 Ma, permitting investigation into environmental evolution coincident with eukaryotic ecosystem evolution and expansion. Here we present multi-proxy geochemical data from the lower Mackenzie Mountains Supergroup to constrain the paleoredox environment within which these large benthic macroalgae thrived. Two transects show evidence for basin-wide anoxic (ferruginous) oceanic conditions (i.e., high FeHR/FeT, low Fepy/FeHR), with muted redox-sensitive trace metal enrichments and possible seasonal variability. However, the weathering of sulfide minerals in the studied samples may obscure geochemical signatures of euxinic conditions. These results suggest that macroalgae colonized shallow environments in an ocean that remained dominantly anoxic with limited evidence for oxygenation until ca. 850 Ma. Collectively, these geochemical results provide novel insights into the environmental conditions surrounding the evolution and expansion of benthic macroalgae and the eventual dominance of oxygenated oceanic conditions required for the later emergence of animals.