Kárita Santos

Ms. Kárita Santos

orcid

Research Focus & Metrics

Academic Career Length

5Years (2022-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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1 January 2022 in Brazilian Journal of Biology
Verified
Journal Article
Open access
VNV. C. Nascimento
V. C. Nascimento
KSKárita Santos
Kárita Santos
KCK. L. Carvalho-Alencar
K. L. Carvalho-Alencar
MCM. B. Castro
M. B. Castro
RKRicardo Henrique Krüger
Ricardo Henrique Krüger
FLFabyano Alvares Cardoso Lopes
Fabyano Alvares Cardoso Lopes
Brazil is one of the world leaders in the agribusiness sector tending to directly influence a growing dependence on imported inputs, specifically synthetic agrochemicals. At the state level, in 2013, Tocantins stood out in first place in the ranking of agrochemical consumers, however, these products can cause several problems, such as poisoning to humans, environmental contamination, and increased resistance to phytopathogens. Biological control is an alternative to the use of agrochemicals towards eliminating pests naturally by using living organisms called Biological Control Agents (BCA). Currently, fungi of the Trichoderma genus are some of the most used organisms in biological pest control for their relevant characteristics that favor them in terms of survival in the environment, such as high capacity to adapt to ecological conditions, potential to colonize the rhizosphere of plants, mycoparasitism, production of volatile and non-volatile metabolites. In addition, it works on plant growth and productivity. In general, the use of Trichoderma favors the control of soil pathogens, such as Rhizoctonia, Pythium, Sclerotinia, and nematodes. Thus, this review aims to demonstrate the importance of using Trichoderma in biological control, as well as to present an overview and perspectives of research developed by respondents in the Brazilian Midwest region and Tocantins state.

5 June 2024 in Biology
Verified
Journal Article
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NRNatana G. Rabelo
Natana G. Rabelo
VGVívian Nicolau Goncalves
Vívian Nicolau Goncalves
MCMarcelo A. Carvalho
Marcelo A. Carvalho
SSSandro Scheffler
Sandro Scheffler
GSGustavo Santiago
Gustavo Santiago
LRLuiz H. Rosa
Luiz H. Rosa
In this study, we evaluated the fungal diversity present associated with cores of Oligocene rocks using a DNA metabarcoding approach. We detected 940,969 DNA reads grouped into 198 amplicon sequence variants (ASVs) representing the phyla Ascomycota, Basidiomycota, Mortierellomycota, Chytridiomycota, Mucoromycota, Rozellomycota, Blastocladiomycota, Monoblepharomycota, Zoopagomycota, Aphelidiomycota (Fungi) and the fungal-like Oomycota (Stramenopila), in rank abundance order. Pseudogymnoascus pannorum, Penicillium sp., Aspergillus sp., Cladosporium sp., Aspergillaceae sp. and Diaporthaceae sp. were assessed to be dominant taxa, with 22 fungal ASVs displaying intermediate abundance and 170 being minor components of the assigned fungal diversity. The data obtained displayed high diversity indices, while rarefaction indicated that the majority of the diversity was detected. However, the diversity indices varied between the cores analysed. The endolithic fungal community detected using a metabarcoding approach in the Oligocene rock samples examined contains a rich and complex mycobiome comprising taxa with different lifestyles, comparable with the diversity reported in recent studies of a range of Antarctic habitats. Due to the high fungal diversity detected, our results suggest the necessity of further research to develop strategies to isolate these fungi in culture for evolutionary, physiological, and biogeochemical studies, and to assess their potential role in biotechnological applications.

13 June 2025 in Microorganisms
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Journal Article
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ATAlonso Poma Ticona
Alonso Poma Ticona
KSKárita Santos
Kárita Santos
HRHeber Esau Ramirez-Arua
Heber Esau Ramirez-Arua
RCRoberto Castellanos Cabrera
Roberto Castellanos Cabrera
JSJéssica Pinheiro PINHEIRO Silva
Jéssica Pinheiro PINHEIRO Silva
FLFabyano Alvares Cardoso Lopes
Fabyano Alvares Cardoso Lopes
The genome of Geobacillus sp. G4, a thermophilic bacterium isolated from a geothermal field in Peru, was sequenced and analyzed to evaluate its taxonomic and biotechnological potential. This strain exhibits optimal growth at temperatures between 50 and 70 °C and at a pH range of 6.0–7.5. Phenotypic assays demonstrated extracellular enzymatic activities, including amylases, cellulases, pectinases, and xylanases, highlighting its potential for efficient polysaccharide degradation. The assembled genome comprises approximately 3.4 Mb with a G+C content of 52.59%, containing 3,490 genes, including coding sequences, rRNAs, and tRNAs. Functional annotation revealed genes associated with key metabolic pathways such as glycogen and trehalose biosynthesis, indicating adaptation to carbohydrate-rich environments. Phylogenetic analyses based on ANI and dDDH values identified Geobacillus thermoleovorans KCTC3570 as its closest relative, suggesting a strong evolutionary relationship. Additionally, the genome harbors gene clusters for secondary metabolites such as betalactone and fengycin, suggesting potential industrial and pharmaceutical applications, including bioremediation. The identification of antibiotic resistance genes, specifically those conferring glycopeptide resistance, underscores their relevance for antimicrobial resistance studies. The presence of enzymes like amylases and pullulanase further emphasizes its biotechnological potential, particularly in starch hydrolysis and biofuel production. Overall, this research highlights the significant potential of Geobacillus species as valuable sources of thermostable enzymes and biosynthetic pathways for industrial applications.

10 March 2025 in DNA
Verified
Journal Article
Open access
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LRLuiz H. Rosa
Luiz H. Rosa
VGVívian Nicolau Goncalves
Vívian Nicolau Goncalves
DBDébora Luiza Costa Barreto
Débora Luiza Costa Barreto
MFMárcio Rocha Francelino
Márcio Rocha Francelino
CBClara Glória Oliveira Baldi
Clara Glória Oliveira Baldi
PCPaulo Camara
Paulo Camara
Background and Methods: We assessed the prokaryotic and eukaryotic diversity present in non-vegetated and vegetated soils on King George Island, Maritime Antarctic, in combination with measurements of carbon dioxide fluxes. Results: For prokaryotes, 381 amplicon sequence variants (ASVs) were assigned, dominated by the phyla Actinobacteriota, Acidobacteriota, Pseudomonadota, Chloroflexota, and Verrucomicrobiota. A total of 432 eukaryotic ASVs were assigned, including representatives from seven kingdoms and 21 phyla. Fungi dominated the eukaryotic communities, followed by Viridiplantae. Non-vegetated soils had higher diversity indices compared with vegetated soils. The dominant prokaryotic ASV in non-vegetated soils was Pyrinomonadaceae sp., while Pseudarthrobacter sp. dominated vegetated soils. Mortierella antarctica (Fungi) and Meyerella sp. (Viridiplantae) were dominant eukaryotic taxa in the non-vegetated soils, while Lachnum sp. (Fungi) and Polytrichaceae sp. (Viridiplantae) were dominant in the vegetated soils. Measured CO2 fluxes indicated that the net ecosystem exchange values measured in vegetated soils were lower than ecosystem respiration in non-vegetated soils. However, the total flux values indicated that the region displayed positive ecosystem respiration values, suggesting that the soils may represent a source of CO2 in the atmosphere. Conclusions: Our study revealed the presence of rich and complex communities of prokaryotic and eukaryotic organisms in both soil types. Although non-vegetated soils demonstrated the highest levels of diversity, they had lower CO2 fluxes than vegetated soils, likely reflecting the significant biomass of photosynthetically active plants (mainly dense moss carpets) and their resident organisms. The greater diversity detected in exposed soils may influence future changes in CO2 flux in the studied region, for which comparisons of non-vegetated and vegetated soils with different microbial diversities are needed. This reinforces the necessity for studies to monitor the impact of resident biota on CO2 flux in different areas of Maritime Antarctica, a region strongly impacted by climatic changes.

28 April 2023 in DESAFIOS - Revista Interdisciplinar da Universidade Federal do Tocantins
Verified
Journal Article
Open access
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KAKamila Lourrane Carvalho Alencar
Kamila Lourrane Carvalho Alencar
VNVanice Conceição Do Nascimento
Vanice Conceição Do Nascimento
KSKárita Santos
Kárita Santos
ARAmanda Rafaela Rodrigues
Amanda Rafaela Rodrigues
FLFabyano Alvares Cardoso Lopes
Fabyano Alvares Cardoso Lopes
O fitopatógeno Sclerotinia sclerotiorum, causador da doença conhecida como mofo-branco acomete diversas culturas agrícolas em todo o mundo, seu alto grau de patogenicidade está associado à formação de escleródios que atuam como mecanismo de resistência e sobrevivência. Considerando a necessidade de métodos que contribuam no desenvolvimento agrícola sem promover danos ao ambiente e a população, os agentes de controle biológico são hoje vistos como um excelente artifício. Fungos do gênero Trichoderma são considerados agentes de biocontrole sagazes por apresentarem inúmeros mecanismos com alto potencial antagônico que prejudicam a germinação de esporos, o crescimento das hifas e o desenvolvimento de escleródios e clamidósporo de diversos fitopatógenos. Buscando avaliar a eficiência de isolados de Trichoderma spp. provenientes de áreas do Cerrado do Tocantins no biocontrole do fitopatógeno S. sclerotiorum foram realizados testes de pareamento, enzimáticos e de produção de metabólitos secundários. Através dos resultados obtidos foi possível concluir que o isolado Trichoderma spp. 2, oriundo de áreas do Cerrado tocantinense, possui potencial para ser considerado como um biocontrolador ao fitopatógeno S. Sclerotiorum, sendo seu antagonismo mais evidente por meio da produção dos metabólitos secundários voláteis.