ABSTRACT The cowpea is a legume that is widely grown in the north-east of Brazil, and which has been gaining ground in other regions of the country. The main producer is the state of Ceará, with a large planted-area, albeit low productivity due to a lack of producer technology and adapted cultivars. The aim of this study was to identify and recommend superior genotypes in terms of adaptability and stability under rainfed and irrigated conditions, in addition to genotypes with reduced grain darkening. To this end, six experiments were conducted in different districts of Ceará (Crato, Pentecoste, Crateús, Madalena, Bela Cruz and Limoeiro do Norte) and one laboratory experiment, to evaluate grain darkening. The experimental design of the field trials was of randomised blocks, with 14 genotypes and 4 replications. The analysis of variance showed a significant effect from the genotypes and environments and their interaction, so GGE Biplot analysis was carried out to evaluate adaptability and stability. To evaluate grain darkening, a completely randomised design was used in a simple factorial scheme with six previously selected genotypes and five different storage times (0, 2, 4, 6 and 8 months). There was a significant effect from the genotypes and storage time. Genotype 1 showed the least darkening, and can be recommended for environments to which it is best adapted (Crato and Crateús). Genotype 9 was considered the most stable for grain yield, and can be more broadly recommended for the semi-arid region of the state of Ceará. northeast north east Brazil country plantedarea, plantedarea planted area, area planted-area cultivars conditions darkening end Crato, Crato Pentecoste Crateús Madalena Norte experiment blocks replications interaction 0, 0 (0 2 months. months . months) time Crateús. Crateús) yield semiarid semi arid (

Fruits of Schinus terebinthifolia Raddi were investigated. A fast and efficient method for the simultaneous determination of 11 polyphenolic substances by high performance liquid chromatography-diode array detector (HPLC-DAD) was applied. Limits of quantification ranged between 0.78 and 3.14 mg L-1. High concentrations of kaempferol were found. An exploratory evaluation was performed using principal component analysis (PCA) for fruit origin differentiation. Total phenolic content (TPC) ranged from 274 to 517 mg GAE 100 g-1; total flavonoid content (TFC) ranged from 101 to 283 mg QE 100 g-1. In vitro analyses showed that antioxidant capacity with 2,2-diphenyl-1-picrylhydrazyl (DPPH) ranged from 1.7 to 7 µM DPPH 100 g-1. The bacteriostatic and bactericidal effect were also evaluated against: Bacillus subtilis, B. cereus, Staphylococcus aureus, Escherichia coli, Pseudomonas aeruginosa, Salmonella choleraesuis, Candida albicans and C. glabrata, using broth microdilution assay. It can be inferred that S. terebinthifolia Raddi fruit has the potential to act as an ally in the search for new alternatives in the action against pathogens, and it can be used as a potential natural antioxidant and antimicrobial agent. Metals (Cu, Fe, Mg, Mn and Zn) were also determined by flame atomic absorption spectrometry (FAAS), with emphasis on high concentrations of Mg, Zn and Fe. investigated 1 chromatographydiode chromatography diode HPLCDAD HPLC DAD (HPLC-DAD applied 078 0 78 0.7 314 3 14 3.1 L1. L1 L 1. L-1 found PCA (PCA differentiation TPC (TPC 27 51 10 g1 g g-1 TFC (TFC 28 g1. 2,2diphenyl1picrylhydrazyl 22diphenyl1picrylhydrazyl diphenylpicrylhydrazyl 2,2 diphenyl picrylhydrazyl 2 (DPPH 17 subtilis B cereus aureus coli aeruginosa choleraesuis C glabrata assay S pathogens agent Cu, Cu (Cu Fe Mg FAAS, FAAS , (FAAS) 07 0. 31 3. L- 5 g- 2diphenyl1picrylhydrazyl 22 2, (FAAS

Poly(amidoamine)-type dendrimers (PAMAM) were synthesized by divergent routes, and generations (G0.5, G1.0, G1.5, G2.0 and G2.5) along with hydroxylated half-generation polymers (G0.5-OH, G1.5-OH and G2.5-OH) were characterized by Fourier-transform infrared spectroscopy, thermogravimetric analysis and differential scanning calorimetry. Carbon dioxide (CO2) capture tests were performed using thermogravimetric analysis. Among the absorption temperatures tested, 60 °C was the most promising: 0.77, 1.08, and 1.14 mol CO2 L 1 for G0.5-OH, G1.5-OH and G2.5-OH, respectively, of CO2 and partial pressure of 45 kPa. This showed that dendrimers with larger molecular structures have more hydroxyl groups and consequently capture more CO2. However, at low partial pressures (< 2 kPa), CO2 solubility in PAMAM increased with temperature reduction, confirmed by Henry’s solubility constant (398.4 mol m3 kPa 1, in G2.5-OH at 40 °C). According to the thermodynamic properties of CO2 solubilization, the process was spontaneous (∆Gsol < 0) and exothermic (∆Hsol < 0). Polyamidoaminetype Poly amidoamine type (PAMAM routes G0.5, G05 G G0 5 (G0.5 G10 G1 0 G1.0 G15 G1.5 G20 G2 G2. G2.5 G25 halfgeneration half generation G0.5OH, G05OH GOH G0.5 OH, OH (G0.5-OH G1.5OH G15OH G2.5OH G25OH Fouriertransform Fourier transform spectroscopy calorimetry CO (CO2 tested 6 C promising 077 77 0.77 108 08 1.08 114 14 1.1 G0.5-OH G2.5OH, respectively 4 However ( kPa, , kPa) reduction Henrys Henry s 398.4 3984 398 (398. m °C. . °C) solubilization ∆Gsol Gsol ∆Hsol Hsol 0. (G0. G1. 5OH G0.5OH G0. (CO 07 7 0.7 10 1.0 11 1. 398. 39 (398 (G0 3 (39 (G (3

This study aimed to isolate, purify and characterize secondary metabolites present in Amburana acreana leaves, native to the state of Rondônia, using classical chromatographic methods and 1D, 2D nuclear magnetic resonance spectroscopy. From the hydroethanolic leaves extract of A. acreana, p-hydroxybenzoic acid, vanillic acid, coumarin, campesterol 3-β-D-glucoside and amburoside B, all known compounds, were identified. To the best of our knowledge, this is the first report of isolation and chemical characterization of secondary metabolites in A. acreana. In addition, in vitro assays indicated that amburoside B does not have inhibitory potential on the growth of gram-negative bacteria. The presence of these compounds suggests that, thus far, amburosides (A and B) could be chemotaxonomic markers of the genus Amburana. isolate Rondônia 1D D spectroscopy A phydroxybenzoic p hydroxybenzoic acid coumarin 3βDglucoside βDglucoside 3 β glucoside identified knowledge addition gramnegative gram negative bacteria far

Bisphenol A (BPA), an endocrine disruptor used in different commercial polymers, is a persistent pollutant commonly found in effluents. Conventional wastewater treatment processes have low chemical removal efficiency and are expensive. This work evaluated BPA removal using laccase enzyme produced from white rot fungus Pleurotus ostreatus. For the enzymatic production, residues of acai berry and pineapple were used as laccase inducers. The use of natural inducers led to a high enzyme production (1139 and 1031 U mL−1 to acai and pineapple, respectively). Bisphenol A was removed to a concentration lower than LOD (limit of detection) after 4 h. The degradation mechanism of BPA occurred by oxidation of methyl to hydroxymethyl group in a propane portion, with breakdown of the aromatic ring. The developed technology brought to the scene a new green, viable methodology, using vegetable waste, adding value to these residues and bringing an alternative to the BPA treatment. BPA, , (BPA) polymers effluents expensive ostreatus 1139 (113 103 mL1 mL 1 mL− respectively. respectively . respectively) limit detection h portion ring green methodology waste (BPA 113 (11 10 11 (1 (

This study aims to propose a new method for derivatizing fatty acids (FAs) from human milk (HM), eliminating the lipid extraction step, and simplifying the preparation for gas chromatography with a flame ionization detection (GC-FID) analysis to quantify the FAs. The Design Expert software optimized the reaction times, concentrations, and sample amount. The proposed method (PM) was validated for lyophilized HM and results for the figures of merit for precision in relative standard deviation (RSD) (RSDintra-day 1.34-4.03% and RSDinter day 2.08 5.16%), accuracy (99.87-102.16%), and robustness are within a linear range of 3 to 38% lipids in HM samples. The atmospheric solids analysis probe tandem mass spectrometry (ASAP-MS/MS) technique confirmed the efficiency of PM by expressing the molecular composition of triacylglycerol formed by FAs from the GC-FID technique. The PM requires a small sample size and conducts derivatization directly in the sample matrix, minimizing extraction errors. (FAs HM, , (HM) step GCFID GC FID (GC-FID times concentrations amount (PM RSD (RSD RSDintraday RSDintra 1.344.03% 134403 1.34 4.03% 1 34 4 03 1.34-4.03 208 2 08 2.0 5.16%, 516 5.16% 5 16 5.16%) 99.87102.16%, 998710216 99.87 102.16% 99 87 102 (99.87-102.16%) 38 samples ASAPMS/MS ASAPMSMS ASAP MS/MS MS (ASAP-MS/MS matrix errors (HM 344 1.344.03 13440 134 1.3 403 4.03 0 1.34-4.0 20 2. 51 5.16 87102 99.87102.16% 99871021 9987 99.8 10216 102.16 9 8 10 (99.87-102.16% ASAPMS MSMS 1.344.0 1344 13 1. 40 4.0 1.34-4. 5.1 8710 99.87102.16 9987102 998 99. 1021 102.1 (99.87-102.16 1.344. 4. 1.34-4 5. 871 99.87102.1 998710 102. (99.87-102.1 1.344 1.34- 99.87102. 99871 (99.87-102. 99.87102 (99.87-102 99.8710 (99.87-10 99.871 (99.87-1 (99.87- (99.87 (99.8 (99. (99 (9 (

The objective of this work was to evaluate the total concentration and bioaccessible fractions of Ba, Ca, Cd, Cr, Cu, Fe, K, Mg, Mn, Pb, V and Zn in berry fruits and analyze the influence of different cultivars and growing conditions on the obtained results. The variations in bioaccessible concentrations were from 7.7-30, 17-29, 22-50, 1.8-96, 22-33 and 20-51% of the total concentration, for Ba, Cu, Fe, Mn, Pb and Zn, respectively. Copper showed greater bioaccessibility in blackberry and blueberry. For Fe, bioaccessibility was observed in all strawberries and blueberries and in some blackberries. Zinc presented higher bioaccessible fractions in strawberries. For V, only the sample Blackberry 124 showed bioaccessible concentration, (11% of the total concentration). Regarding the different forms of cultivation, the strawberries that received radiation from the red and white lamps presented a higher production of fruit compared to the other systems, however, in relation to the absorption of nutrients, a small variation was observed between the fruits. Ba Ca Cd Cr Cu Fe K Mg Mn results 7.730, 7730 7.7 30, 7 30 7.7-30 1729, 1729 17 29, 29 17-29 2250, 2250 22 50, 50 22-50 1.896, 1896 1.8 96, 1 8 96 1.8-96 2233 33 22-3 2051% 2051 20 51% 51 20-51 respectively blueberry blackberries 12 11% 11 (11 concentration. . concentration) cultivation systems however nutrients 730 7.730 773 77 7. 3 7.7-3 172 2 17-2 225 5 22-5 896 1.896 189 18 1. 9 1.8-9 223 22- 205 20-5 (1 73 7.73 7.7- 17- 89 1.89 1.8- 20- (

ABSTRACT Purpose: This study aimed to analyze variations in intraoperative corneal thickness during corneal cross-linking in patients with keratoconus and to investigate its possible correlation with presurgical maximal keratometry (Kmax) and pachymetry. Methods: This was a prospective case series. We used a method similar to the Dresden protocol, with the application of hydroxypropyl methylcellulose 0.1% hypo-osmolar riboflavin in corneas between 330 and 400 µm after epithelium removal. Corneal thickness was measured using portable calipers before and immediately after epithelium removal, and 30 and 60 min after the procedure. Results: The 30 patients in this study were followed up for one year. A statistically significant difference was observed in pachymetry values during the intraoperative period (p<0.0001) and an increase of 3.05 µm (95%C1: 0.56-5.54) for each diopter was seen after epithelium removal (p0.019). We found an average Kmax difference of —2.12 D between men and women (p0.013). One year after treatment, there was a statistically significant reduction in pachymetry (p<0.0001) and Kmax (p0.0170) values. Conclusions: A significant increase in pachymetry measurements was seen during the procedure, and most patients showed a regression in Kmax and pachymetry values one year after surgery. Purpose crosslinking cross linking (Kmax Methods series protocol 01 0 1 0.1 hypoosmolar hypo osmolar 33 40 3 6 procedure Results p<0.0001 p00001 p 0001 (p<0.0001 305 05 3.0 95%C1 95C1 C 95 C1 (95%C1 0.565.54 056554 0.56 5.54 56 5 54 0.56-5.54 p0.019. p0019 p0.019 . p0 019 (p0.019) 2.12 212 2 12 —2.1 p0.013. p0013 p0.013 013 (p0.013) treatment p0.0170 p00170 0170 (p0.0170 Conclusions surgery 0. 4 p<0.000 p0000 000 (p<0.000 3. 95%C 95C 9 (95%C 565 0.565.5 05655 056 0.5 554 5.5 0.56-5.5 p001 p0.01 (p0.019 2.1 21 —2. (p0.013 p0.017 p0017 017 (p0.017 p<0.00 p000 00 (p<0.00 0.565. 0565 55 5. 0.56-5. p00 p0.0 (p0.01 2. —2 p<0.0 (p<0.0 0.565 0.56-5 p0. (p0.0 — p<0. (p<0. 0.56- (p0. p<0 (p<0 (p0 p< (p< (p

Chemometrics is gaining more and more space in universities and industry. To contribute to the development and expansion of principal component analysis (PCA) teaching proposals, this work evaluated the answers of the students to a questionnaire and presented a didactic-pedagogical proposal that can contribute to solving the principal doubts achieved by students in the PCA interpretation. Based on data collected in a semi-open questionnaire, the proposal was developed based on methodological principles of historical-critical pedagogy, containing the objectives, the problems surrounding the topic, and the cultural instruments necessary for understanding and interpreting PCA in the discipline of chemometrics by using new resources and instruments, especially free software, Chemostat. This proposal covers topics related to the concept of chemometrics and PCA, the explanation of the data set, pre-processing, use of Chemostat software, and analysis of principal components. It is hoped that this proposal can promote a better understanding concerning PCA on the part of students, as well as effective incorporation of the phenomena that involve this tool and its applications, and interpretation. Likewise, it is expected that this didactic-pedagogical proposal can support new teaching practices in chemometrics subjects in higher education. industry (PCA proposals didacticpedagogical didactic pedagogical interpretation semiopen semi open historicalcritical historical critical pedagogy objectives topic software set preprocessing, preprocessing pre processing, processing pre-processing components applications Likewise education

Species from Pavonia genus (Malvaceae) are traditionally used as antioxidant, n anti inflammatory and antimicrobial remedies. Previous studies have revealed their diversity of specialized metabolites widely used in the development of new medicines. This is the first study on Pavonia glazioviana Gurke, a Brazilian species known as “Malva da Chapada”. The research led to identify fifteen compounds: 132 (S) hydroxy pheophytin a; and 132(S) hydroxy 173 ethoxyphaeophorbide, n decanol, cycloart 23Z ene 3β,25 diol, cycloart 24S 25 ene 3β,24 diol, sitosterol 3 O β D glucopyranoside, stigmasterol 3 O β D glucopyranoside, quercetin, acacetin, kaempferol, tiliroside, 5 hydroxy 3,7,8,4’ tetramethoxyflavone, 5,7 dihydroxy 3,8,4’ trimethoxyflavone, 5,7 dihydroxy 4’ methoxyflavone, 5,7,4’ trihydroxy 3,8 dimethoxyflavone and 5,7,4’ trihydroxy 3 methoxyflavone. The major flavonoids were tested for their antimicrobial activity, and the compound 5,7 dihydroxy 3,8,4’ trimethoxyflavone showed strong activity against Escherichia coli (MIC = 512 μg mL1), Pseudomonas aeruginosa (MIC = 512 μg mL1), Candida albicans (MIC = 512 μg mL1), Candida tropicalis (MIC = 512 μg mL1), Candida parapsilosis (MIC = 512 μg mL1), Aspergillus flavus (MIC = 512 μg mL1) and A. fumigantus (MIC = 512 μg mL1). The total phenolic content, flavonoid content, and radical scavenging potential were determined showing its great production of phenolics and flavonoids, along with interesting radical scavenging potential (DPPH EC50 = 6.36 ± 0.029 mg mL 1). Our findings contributed to characterize P. glazioviana as a source of methoxylated flavonoids with antimicrobial potential. Malvaceae (Malvaceae antioxidant remedies medicines Gurke Malva Chapada. Chapada . Chapada” compounds 13 S (S 132S 132(S 17 ethoxyphaeophorbide decanol Z 3β25 3β 3β,2 diol 2 3β24 24 glucopyranoside quercetin acacetin kaempferol tiliroside 3,7,8,4 3784 7 8 4 tetramethoxyflavone 57 5, 3,8,4 384 methoxyflavone 5,7,4 574 38 3, MIC 51 mL1, mL1 , A mL1. content DPPH EC EC5 636 6 36 6.3 0029 0 029 0.02 1. 1 1) P 3β2 3β, 3,7,8, 378 3,8, 5,7, 63 6. 002 02 0.0 3,7,8 37 00 0. 3,7, 3,7

Layered double hydroxides (LDHs) and related materials have been studied for a long time and their application in catalytic processes remain attractive due to the tuned properties, morphologies and metal-support interactions obtained from a variety of composition and synthesis route. In this mini-review, some important reactions, such as photocatalysis, electrocatalysis, reduction, carbon-carbon cross-couplings and water-gas shift will be emphasized along with the role of LDHs as catalysts, co-catalysts or catalytic precursors when it was clearly indicated. (LDHs properties metalsupport metal support route minireview, minireview mini review, review mini-review reactions photocatalysis electrocatalysis reduction carboncarbon carbon crosscouplings cross couplings watergas water gas catalysts cocatalysts co indicated

The in silico study aimed to suggest phytochemicals from Commiphora leptophloeos leaves essential oil as therapies against coronavirus disease (COVID-19) (or severe acute respiratory syndrome coronavirus 2, SARS-CoV-2). For that, we used molecular docking (MD), absorption, distribution, metabolism, excretion, and toxicity (ADMET) parameters, and pharmacokinetic analysis. MD showed the presence of hydrophobic and hydrogen bonds for nine compounds. β-Selinene and bicyclogermacrene showed the best interaction values with the protein Mpro (ID: 6Y2F) (-5.9) and chimeric receptor complexed with its receptor human ACE2 (ID: 6VW1) (-6.1 and -5.5) proteins, as well as low gastrointestinal and high epithelial absorptions, medium permeability for Caco-2 cells and high epithelial permeability, low oral excretion, and were inhibitors of CYP2C19 and CYP2C9 enzymes. On the other hand, both were not permeable to the blood-brain barrier and inhibitors or substrates for glycoprotein-D, and showed carcinogenic potential, but only β-selinene was considered mutagenic. Although little bioavailable, both presented aspects structurally adequate, being compounds with moderate synthesis difficulty. Therefore, more analyses are necessary to evaluate the mechanism of action and unsatisfactory parameters foreseen in bioinformatic assays. COVID19 COVID 19 (COVID-19 2 SARSCoV2. SARSCoV2 SARSCoV SARS CoV . SARS-CoV-2) that MD, , (MD) absorption distribution metabolism excretion ADMET (ADMET analysis βSelinene β Selinene ID (ID 6Y2F YF Y F 5.9 59 5 9 (-5.9 ACE 6VW1 VW 6.1 61 6 1 (-6. 5.5 55 -5.5 proteins absorptions Caco2 Caco Caco- CYPC CYP C CYP2C1 CYP2C enzymes hand bloodbrain blood brain glycoproteinD, glycoproteinD glycoprotein D, D glycoprotein-D potential βselinene selinene mutagenic bioavailable adequate difficulty Therefore assays COVID1 (COVID-1 SARS-CoV-2 (MD 5. (-5. 6VW 6. (-6 -5. (COVID- SARS-CoV- (-5 (- -5 (COVID SARS-CoV ( -

Bulk precipitation (BP) samples were collected at two coastal urban sites and two montane Atlantic Forest (400 and 1000 m altitude) areas in southeastern Brazil from August 2008 to August 2009. These samples were analyzed for the major inorganic ions (H+, Na+, K+, Ca2+, Mg2+, Cl- and SO42-) found in rainwater. The concentrations of inorganic nitrogen species (NH4+, NO3- and NO2-) were compiled from a previous study. The volume-weighted mean (VWM) concentrations of inorganic ions differed spatially, with higher values at the coastal urban and coastal periurban sites. On a molar basis, Cl- and Na+ together comprised 60% of the total inorganic constituents at the coastal urban site and 34-42% at the other three sites, as it is the closest to the ocean. Magnesium was also primarily associated with sea-salt aerosol. Non-sea-salt (nss) fractions of K+, Ca2+ and SO42- comprised 68-93% of their VWM concentrations, indicating the contribution of natural (mostly biogenic) and anthropogenic (SO2 oxidation for the latter) sources. Finally, we found that the acidity of BP at the four sampling sites is primarily controlled by the NH4+, nss-Ca2+, nss-SO42-, and NO3- ions, resulting in VWM pH values ranging from 5.60 (lower montane forest) to 5.98 (coastal periurban site). (BP 400 (40 100 altitude 200 2009 H+, H (H+ Na K K+ Ca2 Ca Mg2 Mg Mg2+ Cl SO42 SO rainwater NH4 NH (NH4+ NO3 NO NO2 NO2- study volumeweighted volume weighted (VWM spatially basis 60 3442% 3442 34 42% 42 34-42 ocean seasalt sea salt aerosol Nonseasalt Non nss (nss 6893% 6893 68 93% 93 68-93 mostly biogenic SO2 (SO latter sources Finally NH4+ nssCa2+, nssCa2 nssCa nss-Ca2+ nssSO42, nssSO42 nssSO , nss-SO42- 560 5 5.6 lower forest 598 98 5.9 site. . site) 40 (4 10 20 H+ (H SO4 (NH4 6 344 3 4 34-4 689 9 68-9 nssCa2+ nss-Ca2 nssSO4 nss-SO42 56 5. 59 ( 1 2 (NH 34- 68- nss-Ca nss-SO4 nss-SO

RESUMO: Em geral, alelopatia pode ser definido como o processo biológico no qual um organismo produz metabolitos que alteram a germinação, o crescimento, a sobrevivência e a reprodução de outros organismos, influenciando a estabilidade de agroecossistemas. O colesterol, o mais abundante esterol isolado da alga vermelha marinha Plocamium brasiliense, foi estudado quanto ao seu potencial efeito inibitório na germinação de sementes, alongamento das radículas e desenvolvimento do hipocótilo das ervas daninhas Mimosa pudica (malicia) e Senna obtusifolia (mata-pasto). Colesterol foi isolado do extrato em Hexano por métodos cromatográficos. Durante 15 dias, os bioensaios de germinação foram realizados a 25 ºC e fotoperíodo de 12 horas, enquanto os bioensaio de alongamento da radícula e do hipocótilo foram realizados a 25 ºC e fotoperíodo de 24 horas. Posteriormente, placas de Petri de 9,0 cm de diâmetro foram revestidas de papelfiltro, e 25 sementes foram mantidas em câmaras de germinação, enquanto seis sementes pré-germinadas foram postas em placas de Petri por 2-3 dias. Após dez dias, a extensão da radícula e do hipocótilo foi medida. O potencial inibitório do colesterol foi avaliado a 5, 10, 15 e 20 ppm. Em ambas as ervas M. pudica e S. obtusifolia, foram afetadas significativamente pela ação do cholesterol alcançando maiores percentuais de inibição na germinação das sementes (50% e 33%, respectivamente), alongamento da radícula (68% e 60%, respectivamente) e desenvolvimento do hipocótilo (66% e 55%, respectivamente). Os efeitos inibitórios foram dose-dependentes em todos os experimentos, tendo efeitos alelopaticos mais acentuados a 20 ppm. RESUMO geral crescimento organismos agroecossistemas brasiliense malicia (malicia matapasto. matapasto mata pasto . (mata-pasto) cromatográficos 1 dias 2 horas Posteriormente 90 9 0 9, papelfiltro prégerminadas pré germinadas 23 3 2- medida 5 10 ppm M S 50% 50 (50 33 33% respectivamente, respectivamente , 68% 68 (68 60 60% 66% 66 (66 55 55% respectivamente. dosedependentes dose dependentes experimentos (mata-pasto (5 6 (6 (

ABSTRACT: In general, allelopathy can be defined as a biological process by which an organism produces one or more metabolites that can change the germination, growth, survival, and reproduction of other organisms, and thus influencing the stability of agroecosystems. Cholesterol is a very abundant sterol isolated from the marine red alga Plocamium brasiliense that has been studied regarding its potential inhibitory effects on seed germination, radicle elongation, and hypocotyl development of the weeds Mimosa pudica (malicia) and Senna obtusifolia (mata-pasto). Cholesterol was isolated from a hexane extract by chromatographic methods. Over a 15-day period, germination bioassays were performed at 25 ºC with a 12-h photoperiod. Radicle elongation and hypocotyl development were assayed at 25 ºC with a 24-h photoperiod. Later, Petri dishes 9.0 cm in diameter were coated with filter paper, and 25 seeds were placed in a germination chamber. Six pre-germinated seeds were placed in the Petri dish for 2-3 days. After 10 days, radicle and hypocotyl extensions were measured, and the inhibitory potential of cholesterol was assessed at 5, 10, 15, and 20 ppm. In both herbs, M. pudica and S. obtusifolia, they were significantly affected by the action of cholesterol, achieving higher percentages of inhibition in seed germination (50% and 33%, respectively), radical germination (68% and 60%, respectively), and hypocotyl development (66% and 55%, respectively). The inhibition effects were dose-dependent in all experiments, having more pronounced allelopathic effects at 20ppm. ABSTRACT general growth survival organisms agroecosystems malicia (malicia matapasto. matapasto mata pasto . (mata-pasto) methods 15day day 15 period 2 12h h 12 photoperiod 24h 24 Later 90 9 0 9. paper chamber pregerminated pre germinated 23 3 2- days 1 measured 5 ppm herbs M S 50% 50 (50 33 33% respectively, respectively , respectively) 68% 68 (68 60 60% 66% 66 (66 55 55% respectively. dosedependent dose dependent experiments 20ppm (mata-pasto (5 6 (6 (