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Harmful algal blooms (HABs) cause severe socioecological, economic, food innocuity, and public health problems in countries where aquaculture, fisheries, and tourism share marine ecosystem goods and services. HABs will likely intensify with rising eutrophication, ocean warming, acidification and climatic atmospheric and oceanographic oscillations (e.g. , El Niño). During the Decade of Ocean Science for Sustainable Development (2021–2030), it is imperative to produce knowledge to predict HABs and mitigate their severe negative sustainability consequences. This review on coevolved symbiotic and antagonistic algae-bacteria interactions highlights the HAB holobiome, i.e. , phycosphere-attached and free-living bacteria, as potential bioindicators of bloom onset and decline as they promote, inhibit or suppress algal growth. The reviewed literature led us to discuss (1) the conceptual issues and experimental approach required to generate and include the HAB holobiome data into monitoring schemes to evaluate the resulting predictive model, (2) the relevance of an integrated science-policy approach to articulate the holobiome knowledge among stakeholders, including policymakers, for the efficient use and adaptive management of ecosystem services, and 3) a way to translate, once validated, the holobiome-based predictive model into a widely adopted policy. In this sense, the ongoing Monitoring Algae in Chile project (MACH; www.mach-satreps.org/en/) provides a framework to articulate the holobiome science with policy to establish reliable forecast systems to minimize HAB impact on public health, aquaculture and fisheries activities. This Chilean-Japanese research collaboration builds on the lessons from the catastrophic HAB event on Chiloé Island (May 2016), where world-class salmon, mussel aquaculture, and artisanal fishers coexist. • Harmful algal blooms (HABs) cause severe ecological, socioeconomic, public health and sustainability problems. • The HAB holobiome, symbiotic and antagonist bacteria attached to algae, is a potential bioindicator of bloom dynamics. • The HAB holobiome is potentially a novel, ecosystem-based and complementary tool for HAB monitoring and early warning. • A transdisciplinary approach, including non-scientific stakeholders, is proposed for HAB forecasting and management. [ABSTRACT FROM AUTHOR]

Purpose - The purpose of this paper is to analyse the direct impacts on financial performance and the added value of production in family businesses, considering the efficiency of intellectual capital as determining variables. Design/methodology/approach - A comparative analysis between family businesses (FB) and nonfamily businesses (NFB) is proposed to explore significant differences in the impacts on financial performance and added value of companies, through multivariate techniques. It contributes to the literature on the family business, and its performance from an analytical framework that incorporates the theory of intellectual capital and the measurement of its impact. Findings - The findings show that the value-added coefficient of intellectual capital (VAICTM) is a determining factor in the financial performance of companies and, to a greater extent, in the FB than in their NFB counterparts. It is also verified that the efficiency of intellectual capital in the FB has a direct and greater relationship with the value added of production (VAEmp), with respect to non-family businesses, being an important factor in predicting the performance of companies. Practical implications - The findings allow us to conclude the importance of efficient management of intangible factors in companies, such as intellectual capital, becoming a competitive advantage factor. Originality/value - The document explores the relationship and impact of VAICTM in family businesses that belong to an emerging economy and demonstrates the existence of differences between FB and NFB, at the level of intangible factors under a comparative analysis. [ABSTRACT FROM AUTHOR]

In Chile, the toxic dinoflagellate A. catenella shows an apparent oceanic range expansion from south to the north since its first detection in 1972 in the Magallanes Region (56° S). Until 2017, A. catenella detections were restricted to a geographic area between Magallanes to Los Rios Regions (40° S). The establishment of a monitoring program in the offshore Pacific coast allowed the detection of A. catenella between 2018 and 2019 in northern areas off the Bío-Bío Region (36°S). Monoclonal cultures established from the Bío-Bío coast were genetically identified, and PSTs screened. Phylogenetic analyses determined that the Bío-Bío isolates aggregated in Group I ribotype (previously A. tamarense or A. fundyense) and the presence of PSTs analogs were confirmed. It is the northernmost detection of the toxic dinoflagellate A. catenella in the Pacific coast of Chile. These results have important implications for species monitoring and governmental management in the Bío-Bío Region. • The detection of A. catenella off the Bío-Bío Region represents the northernmost record of this species on the Chilean coast. • Morphology and phylogeny of cultured A. catenella from the Bío-Bío coast confirmed species identification. • PSTs quantification in A. catenella isolates from the Bio-Bio region represents a potential PSP risk in the area. [ABSTRACT FROM AUTHOR]

• Gymnodimine was detected in shellfish of the Chilean Pacific coast. • Gymnodimine has not yet been linked with a microalga especies in Chilean waters. • A. ostenfeldii culture was established through resting cyst germination. • Detection of paralyzing toxins of A. ostenfeldii culture. The study of marine toxins in shellfish is of the utmost importance to ensure people's food safety. Marine toxins in shellfish and microalgae in the water column off the south-central coast of Chile (36°‒43° S) were studied in a network of 64 stations over a 14-month period. The relative abundance of harmful species Alexandrium catenella, Alexandrium ostenfeldii, Protoceratium reticulatum, Dinophysis acuminata, Dinophysis acuta, Pseudo-nitzschia seriata group and P. delicatissima group was analyzed. The detection and quantification of lipophilic toxins and domoic acid (DA) in shellfish was determined by UHPLC-MS/MS, and for Paralytic Shellfish Toxins (PSTs) by HPLC-FD with post-column oxidation, while for a culture of A. ostenfeldii a Hylic-UHPLC-MS/MS was used. Results showed that DA, gonyautoxin (GTX)-2, GTX-3 and pectenotoxin (PTX)-2 were detected below the permitted limits, while Gymnodimine (GYM)-A and 13-desmethylespirolide C (SPX-1) were below the limit of quantitation. According to the distribution and abundance record of microalgae, DA would be associated to P. seriata and P. delicatissima -groups, PTX-2 to D. acuminata , and GTX-2, GTX-3, GYM-A, and SPX-1 to A. ostenfeldii. However, the toxin analysis of an A. ostenfeldii culture from the Biobío region only showed the presence of the paralytic toxins C2, GTX-2, GTX-3, GTX-5 and saxitoxin, therefore, the source of production of GYM and SPX is still undetermined. [ABSTRACT FROM AUTHOR]

• Dinophysis acuminata and D. acuta showed a poleward positive gradient in S Chile. • Blooms (103 cells L‒1) of Dinophysis acuta no longer occur in Los Lagos Region (∼41°S). • FW layer in fjords decline with decreasing trend in rainfall and river discharge. • D. acuta blooms linked to absence of the FW (salinity < 11) layer in Chilean fjords. • D. acuminata containing only PTX2 (now EC de-regulated), no threat to the region. Dinophysis acuminata and D. acuta, which produce diarrheogenic toxins and pectenotoxins in southern Chile, display site-specific differences in interannual variability (2006 – 2018) in Reloncaví, Pitipalena and Puyuhuapi fjords (41 – 46 °S), Chilean Patagonia. Linear Models show decreasing trends in rainfall and river discharge. Latitudinal decreasing gradients in SST temperature and vertical salinity gradients were observed. A brackish water layer (FW salinity <11 psu), permanently present in Reloncaví, decreased in thickness with time in Pitipalena and was usually absent in Puyuhuapi, the only fjord where D. acuta reached bloom (>103 cells L‒1) densities every season. Dinophysis acuminata, associated with toxin profiles in shellfish that include only pectenotoxins, bloomed everywhere with a poleward increasing gradient. Absence of the FW layer provides a possible index of risk for D. acuta blooms. An apparent poleward shift of D. acuta populations, responsible for DSP outbreaks in Reloncaví in the 1970s, and the recent EU deregulation of pectenotoxins will have a positive impact on the mussel industry in Los Lagos Region. Changes to ongoing monitoring protocols to improve risk assessment capabilities are suggested. [ABSTRACT FROM AUTHOR]

The Reloncaví estuary in southern Chile is famous for its aquaculture. However, recurring harmful algal blooms have adversely affected mussel production. Therefore, regular monitoring of algal toxins is urgently needed to better understand the contamination status of the estuary. In this study, we quantified 15 types of lipophilic shellfish toxins in Metri Bay in the Reloncaví estuary on a biweekly basis for 4 years. We identified algal species using microscopy and metabarcoding analysis. We also measured water temperature, salinity, chlorophyll-a, and dissolved oxygen to determine the potential relationships of these parameters with algal toxin production. Our results revealed the presence of a trace amount of pectenotoxin and the causal phytoplankton Dinophysis, as well as yessotoxin and the causal phytoplankton Protoceratium. Statistical analysis indicated that fluctuations in water temperature affected the detection of these toxins. Additionally, metabarcoding analysis detected the highly toxic phytoplankton Alexandrium spp. in some samples. Although our results suggest that the level of lipophilic shellfish toxins in Metri Bay during the study period was insignificantly low using our current LC-MS method, the confirmed presence of highly toxic algae in Metri Bay raises concerns, given that favorable environmental conditions could cause blooms., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 The Authors. Published by Elsevier B.V. All rights reserved.)

The dinoflagellate Alexandrium catenella is a well-known paralytic shellfish toxin producer that forms harmful algal blooms, repeatedly causing damage to Chilean coastal waters. The causes and behavior of algal blooms are complex and vary across different regions. As bacterial interactions with algal species are increasingly recognized as a key factor driving algal blooms, the present study identifies several bacterial candidates potentially associated with Chilean Alexandrium catenella. This research narrowed down the selection of bacteria from the Chilean A. catenella culture using antibiotic treatment and 16S rRNA metabarcoding analysis. Subsequently, seawater from two Chilean coastal stations, Isla Julia and Isla San Pedro, was monitored for two years to detect Alexandrium species and the selected bacteria, utilizing 16S and 18S rRNA gene metabarcoding analyses. The results suggested a potential association between Alexandrium species and Spongiibacteraceae at both stations. The proposed candidate bacteria within the Spongiibacteraceae family, potentially engaging in mutualistic relationships with Alexandrium species, included the genus of BD1-7 clade, Spongiibbacter, and Zhongshania., Competing Interests: The authors have declared that no competing interests exist., (Copyright: © 2024 Yarimizu et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.)

Harmful algae blooms (HABs) monitoring has been implemented worldwide, and Chile, a country famous for its fisheries and aquaculture, has intensively used microscopic and toxin analyses for decades for this purpose. Molecular biological methods, such as high-throughput DNA sequencing and bacterial assemblage-based approaches, are just beginning to be introduced in Chilean HAB monitoring, and the procedures have not yet been standardized. Here, 16S rRNA and 18S rRNA metabarcoding analyses for monitoring Chilean HABs are introduced stepwise. According to a recent hypothesis, algal-bacterial mutualistic association plays a critical synergetic or antagonistic relationship accounting for bloom initiation, maintenance, and regression. Thus, monitoring HAB from algal-bacterial perspectives may provide a broader understanding of HAB mechanisms and the basis for early warning. Metabarcoding analysis is one of the best suited molecular-based tools for this purpose because it can detect massive algal-bacterial taxonomic information in a sample. The visual procedures of sampling to metabarcoding analysis herein provide specific instructions, aiming to reduce errors and collection of reliable data.

Phytoplankton blooms, including harmful algal blooms (HABs), have serious impacts on ecosystems, public health, and productivity activities. Rapid detection and monitoring of marine microalgae are important in predicting and managing HABs. We developed a toolkit, the Suitcase Lab, to detect harmful algae species in the field. We demonstrated the Suitcase Lab's capabilities for sampling, filtration, DNA extraction, and loop-mediated isothermal amplification (LAMP) detection in cultured Alexandrium catenella cells as well as Chilean coastal waters from four sites: Repollal, Isla García, Puerto Montt, and Metri. A LAMP assay using the Suitcase Lab in the field confirmed microscopic observations of A. catenella in samples from Repollal and Isla García. The Suitcase Lab allowed the rapid detection of A. catenella, within 2 h from the time of sampling, even at a single cell per milliliter concentrations, demonstrating its usefulness for quick and qualitative on-site diagnosis of target toxic algae species. This method is applicable not only to detecting harmful algae but also to other field studies that seek a rapid molecular diagnostic test.

Harmful algae blooms (HABs) cause acute effects on marine ecosystems due to their production of endogenous toxins or their enormous biomass, leading to significant impacts on local economies and public health. Although HAB monitoring has been intensively performed at spatiotemporal scales in coastal areas of the world over the last decades, procedures have not yet been standardized. HAB monitoring procedures are complicated and consist of many methodologies, including physical, chemical, and biological water sample measurements. Each monitoring program currently uses different combinations of methodologies depending on site specific purposes, and many prior programs refer to the procedures in quotations. HAB monitoring programs in Chile have adopted the traditional microscopic and toxin analyses but not molecular biology and bacterial assemblage approaches. Here we select and optimize the HAB monitoring methodologies suitable for Chilean geography, emphasizing on metabarcoding analyses accompanied by the classical tools with considerations including cost, materials and instrument availability, and easiness and efficiency of performance. We present results from a pilot study using the standardized stepwise protocols, demonstrating feasibility and plausibility for sampling and analysis for the HAB monitoring. Such specific instructions in the standardized protocol are critical obtaining quality data under various research environments involving multiple stations, different analysts, various time-points, and long HAB monitoring duration.