Journal of Applied Phycology最新文献

{"title":"Temporal variation in the incidence of seaweed health problems affecting farmed Kappaphycus striatus in relation to environmental conditions in shallow waters","authors":"Joseph P. Faisan, Rema C. Sibonga, Jonalyn P. Mateo, Maria Rovilla J. Luhan, Victor Marco Emmanuel N. Ferriols, Vicente T. Balinas, Janina Brakel, David Bass, Stuart Ross, Grant D. Stentiford, Juliet Brodie, Georgia M. Ward, Anicia Q. Hurtado","doi":"10.1007/s10811-024-03242-w","DOIUrl":"https://doi.org/10.1007/s10811-024-03242-w","url":null,"abstract":"<p>A fixed off-bottom <i>Kappaphycus striatus</i> var<i>. sacol</i> farm was monitored for 12 months (June 2019 to May 2020) and the monthly incidence of disease and pests was recorded. Meteorological information <i>in situ,</i> from the nearest synoptic station and online data were collected to determine the relationships between temporal environmental changes and the incidence of seaweed health problems. The results showed that “ice-ice” disease (IID) was observed in dry months (i.e., from February to April 2020) and was significantly influenced by increased irradiance, salinity, sea surface temperature, and wind speed (<i>p=</i>0.004‒0.030). Also, the IID incidence was positively affected by reduced precipitation, storm surface run-off, water current speed, and inorganic nutrient (nitrite and ammonia) levels (<i>p=</i>0.002‒0.019). In comparison, epiphytic filamentous algae (EFA) were observed in wet months (i.e., from September to December 2019), with incidence varying from low to very high (≤25–100%) as the culture progressed. EFA incidence was significantly influenced by reduced salinity and increased storm surface run-off and inorganic nutrient (nitrate and ammonia) levels (<i>p=</i>0.006‒0.040). An intense tropical cyclone struck the farming area in December 2019, resulting in partial die-offs of farmed seaweed. Such seaweed health problems are expected to become more prevalent in the coming years as weather disturbances brought about by changing weather patterns become more frequent and intense. Hence, mitigation and preventative approaches must be fully considered to sustain the industry’s growth while protecting the livelihoods of many coastal communities dependent on seaweed farming.</p>","PeriodicalId":15086,"journal":{"name":"Journal of Applied Phycology","volume":"173 1","pages":""},"PeriodicalIF":3.3,"publicationDate":"2024-04-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140612227","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Dinoflagellate Tripos species composition and seasonal dynamics in Jiaozhou Bay revealed through 18S rDNA V4-based metabarcoding analysis","authors":"Xianliang Huang, Kuiyan Liu, Xiangxiang Ding, Shuya Liu, Zhongmei Cui, Yongfang Zhao, Nansheng Chen","doi":"10.1007/s10811-024-03239-5","DOIUrl":"https://doi.org/10.1007/s10811-024-03239-5","url":null,"abstract":"<p><i>Tripos</i> is one of the largest dinoflagellate genera with ~800 reported taxa widely distributed in global marine ecosystems. These diverse <i>Tripos</i> species are ecologically important as critical primary producers and some <i>Tripos</i> species are also harmful algal bloom (HAB) species that may pose significant negative impact on marine ecosystems. However, due to the high morphological intraspecific variability and plasticity of numerous <i>Tripos</i> species, morphology-based identification and tracking of their dynamic changes have been both technically challenging and inconclusive. In this project, we carried out metabarcoding analysis of <i>Tripos</i> species in Jiaozhou Bay (JZB) through amplifying and sequencing of the common molecular marker 18S rDNA V4. The analysis identified five <i>Tripos</i> species (<i>T. furca</i>, <i>T. fusus</i>, <i>T. eugrammus</i>, <i>T. falcatus</i> and <i>T. massiliensis</i>), including two (<i>T. eugrammus</i> and <i>T. falcatus</i>) identified for the first time in JZB, demonstrating the competitive strength of metabarcoding analysis. This analysis of time-series samples collected in JZB revealed interesting seasonal dynamic changes of <i>Tripos</i> species, with different species demonstrating differential seasonal preferences. This analysis also suggested the possible existence of 11 additional <i>Tripos</i> species in JZB. The inconclusive identification of these 11 potential <i>Tripos</i> species indicated that the resolution of the common molecular marker 18S rDNA V4 applied in this study is inadequate and that the molecular reference data for <i>Tripos</i> is still limited. Selection of molecular markers with higher resolution (such as 28S rDNA D1-6) and the completion of reference sequences of <i>Tripos</i> species may facilitate more accurate identification of and tracking of their dynamic changes.</p>","PeriodicalId":15086,"journal":{"name":"Journal of Applied Phycology","volume":"38 1","pages":""},"PeriodicalIF":3.3,"publicationDate":"2024-04-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140560042","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Supplementation of tropical red seaweeds improved gut health indices, antioxidant status and immunity in adult dogs","authors":"K. Y. Srinivas, A. Das, P. Bagavan Reddy, A. K. Verma","doi":"10.1007/s10811-024-03229-7","DOIUrl":"https://doi.org/10.1007/s10811-024-03229-7","url":null,"abstract":"<p>We explored the effect of supplementation of two tropical red seaweeds, <i>Kappaphycus alvarezii</i> (KA) and <i>Gracilaria salicornia</i> (GS) at three different levels (0, 1.5 and 3%) on nutrient utilization, gut health, antioxidant, and immune status in adult dogs. The experiment was based on a 5 x 5 Latin square design (LSD) comprising five adult Labrador dogs, five dietary treatments (CON: basal diet; KA_L: KA at 1.5 % of diet dry matter (DM); KA_H: KA at 3 % DM; GS_L: GS at 1.5 % DM; GS_H: GS at 3 % DM) and five periods, each of 21 days, followed by a 7-day washout period in between. The palatability, food intake, and body weight changes were comparable among the groups (<i>P</i>&gt;0.05). The supplementation of two seaweeds at either level did not have any effect on nutrient digestibility (<i>P</i>&gt;0.05). The fecal lactate concentration was higher (<i>P</i>&lt;0.05) in GS_L and GS_H groups whereas fecal ammonia was lower (<i>P</i>&lt;0.05) in the GS_H group in comparison to the other groups. The volatile fatty acids (VFA) profile improved (<i>P</i>&lt;0.05) in the KA_H, GS_L, and GS_H groups. The mean fecal <i>Lactobacillus</i> count tended to increase (<i>P</i>&lt;0.10) in the KA_H and GS_H groups while the <i>coliform</i> count remained unaffected by seaweed supplementation. The mean fecal <i>Bifidobacterium</i> population was higher (<i>P</i>&lt;0.05) and the mean <i>clostridial</i> population was lower (<i>P</i>&lt;0.05) in the GS_H group as compared to -other groups. The concentration of reduced glutathione (GSH) was higher (<i>P</i>&lt;0.05) and lipid peroxides were lower in the KA_H and GS_H groups. A tendency (<i>P</i>&lt;0.10) of improved cell-mediated immunity (CMI) was observed in the GS_H group as compared to other groups. Overall, the supplementation of either of the seaweeds at 1.5 % failed to exert significant influence on any of the parameters studied except fecal VFA and lactate levels, whereas both the seaweeds at 3% level showed some promising benefits in terms of improved gut health, antioxidant, and immune status and the best response was obtained in GS_H group. Hence, it can be concluded that supplementation of GS at the 3 % level outperformed KA supplementation at the 3 % level by improving gut health, antioxidant status and immunity.</p>","PeriodicalId":15086,"journal":{"name":"Journal of Applied Phycology","volume":"388 1","pages":""},"PeriodicalIF":3.3,"publicationDate":"2024-04-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140560152","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Seaweed extract ameliorates salt stress in tomato plants by enhancing the antioxidant system and expression of stress-responsive genes","authors":"Rosalba Mireya Hernández-Herrera, Juan Florencio Gómez-Leyva, Carla Vanessa Sánchez-Hernández, Héctor Ocampo-Álvarez, Ricardo Ramírez-Romero, Paola Andrea Palmeros-Suárez","doi":"10.1007/s10811-024-03236-8","DOIUrl":"https://doi.org/10.1007/s10811-024-03236-8","url":null,"abstract":"<p>Biostimulants such as seaweed extracts are widely used to stimulate plant growth and crop productivity under optimal or stressful conditions, constituting a sustainable strategy to mitigate the impacts of abiotic stress on plant performance. In this study, a growth experiment was conducted to evaluate the effects of an aqueous extract from the seaweed <i>Padina gymnospora</i> on the physiological, biochemical, and molecular characteristics of <i>Solanum lycopersicum</i> under salt stress. The experiment included four treatments: 1) control plants, 2) plants irrigated with 300 mM NaCl solution, 3) plants treated with the <i>P. gymnospora</i> extract, and 4) plants treated with the <i>P. gymnospora</i> extract and irrigated with 300 mM NaCl solution. Salt stress increased the activity of antioxidant enzymes (catalase and superoxide dismutase) and resulted in the overaccumulation of the osmolyte proline and flavonoids while enhancing photosynthetic performance and chlorophyll content. In addition, treatment with <i>P. gymnospora</i> extract increased total reducing sugars and phenols in salt-stressed plants, which was correlated with DPPH and ABTS antioxidant activity. The induction of stress-responsive genes, such as <i>SlHB7, SlSOD1, SlRD29</i>, and <i>SlHKT,</i> appears to be a major factor modulating the responses to <i>P. gymnospora</i> extract application in tomato plants. The results of this study demonstrate that the application of <i>P. gymnospora</i> to tomato plants attenuated the damage caused by salt stress. It is essential to continue studying the potential of seaweed extracts to mitigate stress in plants, given the promising agricultural applications of these novel biostimulants.</p>","PeriodicalId":15086,"journal":{"name":"Journal of Applied Phycology","volume":"174 1","pages":""},"PeriodicalIF":3.3,"publicationDate":"2024-04-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140560125","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A contagious disease caused serious damage to Gracilariopsis lemaneiformis cultivation in China","authors":"Tong Pang, Feng Wang, Xiaobin Yang, Jianguo Liu, Hongjun Xu, Qunqun Guo, Liyuan Liu","doi":"10.1007/s10811-024-03246-6","DOIUrl":"https://doi.org/10.1007/s10811-024-03246-6","url":null,"abstract":"<p>The yield of <i>Gracilariopsis lemaneiformis</i> in China was reduced by at least 40% in 2023 compared with 2022. Based on the investigation of this study, the decrease in production was caused by a disease locally named ‘Baotou’. The first sign of ‘Baotou’ disease was observed with the appearance of many light red branches in the thalli of <i>G. lemaneiformis</i>. During the onset of ‘Baotou’ disease, <i>G. lemaneiformis</i> lost its original red color and eventually decayed. One of the most typical morphological characteristics of ‘Baotou’ is that the closer the thalli were to the attachment rope, the more they decayed. Compared with the flat and regular epidermal cells of healthy alga, diseased algae had a rough surface covered with mucilaginous substance and numerous bacteria were found within the mucilaginous substance. The number of decayed points was significantly increased when the healthy cuttings were placed near the ‘Baotou’ cuttings. Pathogenic bacteria, which can induce the decay of healthy <i>G. lemaneiformis</i>, can be obtained from the ‘Baotou’ diseased <i>G. lemaneiformis</i>. The ‘Baotou’ disease is contagious. Once the <i>G. lemaneiformis</i> are infected with ‘Baotou’ disease, they should be harvested timely to prevent them from infecting the healthy alga.</p>","PeriodicalId":15086,"journal":{"name":"Journal of Applied Phycology","volume":"25 1","pages":""},"PeriodicalIF":3.3,"publicationDate":"2024-04-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140560216","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Microwave-assisted extraction of lipid and eicosapentaenoic acid from the microalga Nanochloropsis sp. using imidazolium-based ionic liquids as an additive in water","authors":"Shiva Rezaei Motlagh, Ramin Khezri, Mohammad Etesami, Ching Yern Chee, Soorathep Kheawhom, Kasidit Nootong, Razif Harun","doi":"10.1007/s10811-024-03244-8","DOIUrl":"https://doi.org/10.1007/s10811-024-03244-8","url":null,"abstract":"<p>This study employed 1-ethyl-3-methyl imidazolium chloride ([EMIM][Cl]) as an additive in an aqueous medium, combined with microwave-assisted extraction (IL-MAE), to extract total lipids and eicosapentaenoic acid (EPA) from the microalga <i>Nannochloropsis</i> sp<i>.</i> microalgae. The optimization process involved evaluating critical operating parameters, including the type of extraction solvent, solid-loading (i.e., water: microalgae ratio), extraction time, extraction temperature, and the IL/biomass ratio on the extraction of total lipids and as well as its EPA content. Under optimal conditions, IL-MAE significantly enhanced total lipid yield and EPA content by approximately 2.72 times and 8.1 times, respectively, compared to the traditional Soxhlet extraction. The standard Soxhlet procedure resulted in approximately 6.20% total lipids and 4.61 mg g^-1 of EPA. Notably, with IL-MAE, the highest lipid and EPA yields were achieved. These reached 16.87% and 37.28 mg g^-1, respectively, under optimal conditions: 90 °C for 25 min, using 2 w/w IL/biomass ratio, with 0.5 g of algae and a 3.3% w/v solid-loading. The obtained FAMEs through transesterification of total lipids exhibited high quality, comprising 37.94% wt polyunsaturated fatty acids (PUFAs). SEM and FTIR confirmed IL-MAE's superior lipid extraction by disrupting glycosidic linkages in the microalgal cell wall, resulting in a significantly higher yield than Soxhlet extraction. Repeated use of recycled [EMIM][Cl], tested up to four times, did not impact lipid and fatty acids recovery. Cost evaluation revealed that the IL-MAE approach for lipid production from <i>Nannochloropsis</i> sp<i>.</i> is more cost-efficient than the Soxhlet method, considering biomass, chemical and energy consumption. The enhanced extraction performance and accelerated rates of the IL-MAE system demonstrate its efficacy in extracting lipids, EPAs, and PUFAs from microalgae. Furthermore, it emphasizes sustainable, green, and efficient approach for extracting bioactive compounds, offering potential applications in the pharmaceutical and nutraceutical industries.</p>","PeriodicalId":15086,"journal":{"name":"Journal of Applied Phycology","volume":"38 1","pages":""},"PeriodicalIF":3.3,"publicationDate":"2024-04-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140559919","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The Vertical Migration Dynamic of Microcystis aeruginosa in a Water Column","authors":"Hongyu Yan, Mudalige Don Hiranya Jayasanka Senavirathna, Takeshi Fujino","doi":"10.1007/s10811-024-03241-x","DOIUrl":"https://doi.org/10.1007/s10811-024-03241-x","url":null,"abstract":"<p>The prediction and numerical modeling of cyanobacterial outbreaks have emerged as a significant research topic. Presently, in-situ and remote sensing observations serve as the primary foundation for numerical modeling. Owing to the influence of local environmental factors on fieldwork-based models, cross-sectional comparisons among distinct models remain challenging. In this study, three tanks (height: 1.8m) were installed in the laboratory to represent the structure of vertical zone in shallow lakes, and <i>Microcystis aeruginosa</i> culture was observed under a 12/12 light cycle for one month maintaining constant conditions. The findings indicate that light intensity, duration, and light-dark cycling all impact vertical migration of <i>M. aeruginosa</i>. <i>Microcystis aeruginosa</i> exposed to low light intensities (18 to 39 μmol photons m^-2 s^-1) migrated more rapidly than those under high light intensities (447 to 466 μmol photons m^-2 s^-1); cells subjected to extended illumination (over 8 hours) exhibited stable distribution patterns; and, in darkness, cyanobacteria that were in high light intensity areas responded more swiftly compared to those that were in low light intensity areas. The findings suggest that <i>M. aeruginosa</i> vertical migration is continuous and dynamic, and not vitally light intensity dependent. To effectively conduct cross-sectional comparisons of models across lakes, it is imperative to thoroughly consider the diurnal variation of vertical migration of <i>M. aeruginosa</i>. Based on the research results, recommendations for changes to the current vertical migration numerical model are provided.</p>","PeriodicalId":15086,"journal":{"name":"Journal of Applied Phycology","volume":"34 1","pages":""},"PeriodicalIF":3.3,"publicationDate":"2024-04-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140560381","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Effects of light quality on the growth, productivity, fucoxanthin accumulation, and fatty acid composition of Thalassiosira pseudonana","authors":"Maoyingzang Peng, Shiyu Lin, Yinghan Shen, Ruibing Peng, Sheng Li, Xiamin Jiang, Maowang Jiang","doi":"10.1007/s10811-024-03245-7","DOIUrl":"https://doi.org/10.1007/s10811-024-03245-7","url":null,"abstract":"<p><i>Thalassiosira pseudonana</i>, a fast-growing and nutritionally rich planktonic diatom, has been cultivated on a large scale as high-quality plankton feed. Despite this, studies exploring the impact of light quality on the growth and compositional attributes of this algal species are scarce. This study investigated the effects of five different light qualities—white, red, yellow, green, and blue—on the growth, biomass, fucoxanthin accumulation, and fatty acid composition and content of <i>T. pseudonana</i>. The results indicated that <i>T. pseudonana</i> achieved the highest growth rate and greatest biomass under white and blue light, with the poorest performance observed under red light. Moreover, fucoxanthin accumulation was most pronounced under blue light, reaching 4.729 ± 0.182 mg g^-1, followed in descending order by yellow, red, white, and green light. The total lipid content was highest under yellow light at 34%, significantly surpassing the levels observed under other conditions, with the order of effectiveness being blue light &gt; green light ≥ red light ≥ white light. Analysis of fatty acid composition revealed a greater diversity under blue light, with a total of 15 types, whereas green light yielded only 10 types. The proportion of unsaturated fatty acids was highest under blue light at 69.71%, followed by yellow, white, green, and red light. Specifically, the performance of polyunsaturated fatty acids (PUFAs) varied as follows: yellow light (36.7%) &gt; blue light (34.09%) &gt; white light (33.29%) &gt; green light (23.67%) &gt; red light (17%). The concentration of eicosapentaenoic acid (EPA) was significantly greater under blue (17.03%) and yellow (16.31%) light compared to other treatments, with the lowest concentration (8.84%) observed under red light. In conclusion, blue light significantly enhances the growth rate of <i>T. pseudonana</i> and fosters fucoxanthin accumulation. Both yellow and blue light are favorable for the accumulation of PUFAs and EPA.</p>","PeriodicalId":15086,"journal":{"name":"Journal of Applied Phycology","volume":"9 1","pages":""},"PeriodicalIF":3.3,"publicationDate":"2024-04-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140560038","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Tisochrysis lutea as a source of omega-3 polar lipids and fucoxanthin: extraction and characterization using green solvents and advanced techniques","authors":"Paz García-García, Mónica Ospina, Francisco J. Señoráns","doi":"10.1007/s10811-024-03233-x","DOIUrl":"https://doi.org/10.1007/s10811-024-03233-x","url":null,"abstract":"<p>The marine microalga <i>Tisochrysis lutea</i> is a potential and sustainable source of bioactive compounds such as carotenoids and omega-3 fatty acids. In the present work, the extraction of fucoxanthin and docosahexaenoic acid (DHA), the most abundant omega-3 fatty acid which constitutes polar lipids particularly in the brain, was studied using advanced extraction techniques with green and bio-based solvents compared to traditional extraction techniques with hazardous organic solvents. The experimental design to maximize the lipid extraction yield by ultrasound-assisted extraction (UAE) was developed, choosing as experimental factors the percentage of solvent (0, 50 and 100% of 2-methyl-tetrahydrofuran or 2-methyloxolane (2-me-THF) in ethanol), the extraction time (20, 30 and 40 min) and temperature (40, 50 and 60 ºC). The highest lipid extraction yields were obtained using ethanol as solvent. Nevertheless, the most interesting extracts based on their chemical composition were obtained when the presence of 2-me-THF in the extraction mixture was greater than that of ethanol. Through analytical techniques such as HPLC-ELSD/DAD and GC-MS as well as spectrophotometric techniques, the contents of polar lipids, fatty acids, total carotenoids and fucoxanthin were quantified. In addition, the antioxidant capacity of different selected extracts was studied, being once again the most interesting those extracted with different amounts of 2-me-THF due to its selectivity and enriched composition in high-added value bioactives, mainly fucoxanthin and DHA. Therefore, it is shown the importance of choosing an advanced extraction technique together with the use of green solvents not only to develop procedures that are in agreement with Green Chemistry but also to preserve its bioactivity.</p>","PeriodicalId":15086,"journal":{"name":"Journal of Applied Phycology","volume":"15 1","pages":""},"PeriodicalIF":3.3,"publicationDate":"2024-04-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140560041","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Biostimulating activity of biomass extracts and supernatants from a culture of Arthrospira platensis enriched with L-tryptophan","authors":"Natali López Mejía, Hugo Alexander Martínez Correa, Hugo Fabian Lobatón García","doi":"10.1007/s10811-024-03237-7","DOIUrl":"https://doi.org/10.1007/s10811-024-03237-7","url":null,"abstract":"<p>The present study was conducted with the aim of evaluating the effects, over 6 days, of different intensities of continuous light (20, 40, and 60 µmol photons m^-2 s^-1) on the growth of <i>Arthrospira platensis</i> and its impact on the production of phycocyanin, carotenoids, and intracellular/extracellular auxins, using a medium supplemented with 0.5 g L^-1 of L-tryptophan. Additionally, the study aimed to assess the effect of treatments on the biostimulant activity of the supernatant (T₀: untreated, T₁: treated) compared to that of biomass extracts (T₂). T₀, T₁, and T₂ were adjusted to a concentration of 0.1 mg L^-1 of indole-3-acetic acid (IAA) and a pH of 7.4. The results revealed that light intensities of 40 and 60 µmol photons m^-2 s^-1 produced the highest levels of extracellular IAA on day 2 (20.1 and 33.01 mg L^-1, respectively), while an intensity of 20 µmol photons m^-2 s^-1 reached peak IAA production on day 3 (25.74 mg L^-1), followed by a subsequent decrease. Phycocyanin concentrations markedly decreased after maximal IAA production under all light conditions. Tukey's analysis indicated that treatments T₁ and T₂ significantly increased the number and length of secondary roots in mung beans by 157% and 350%, respectively, with no significant differences between them, while the untreated supernatant (T₀) exhibited a minor effect. The study concludes that under all assessed light conditions, concentrations of phycocyanin and carotenoids drastically decreased after peak IAA production, gradually recovering in the following days. Additionally, the treated supernatant and biomass extract significantly enhanced root growth in mung beans, highlighting the importance of the treatment method for biostimulation and suggesting potential for improved storage and transportation. Future research should focus on refining supernatant treatments to optimize biostimulant activity and facilitate commercialization.</p>","PeriodicalId":15086,"journal":{"name":"Journal of Applied Phycology","volume":"114 1","pages":""},"PeriodicalIF":3.3,"publicationDate":"2024-04-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140559892","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}