Molecular Docking Studies to Identify Inhibitors of Norepinephrine Reuptake from Marine Algae

Depression is one of the major mental health problems at prevalence now days. It can be characterized by poor concentration, low self-esteem, losing interest in family or social life, feeling tired or fatigue, suicidal thoughts and similar symptoms. There are treatments like psychotherapies, antidepressants and electroconvulsive therapies available, but there is need to identify more effective treatment with lesser side effects. Marine organisms like algae, sponges or corals are been investigated to explore their potential as antidepressants. This article aims to explore the potential of some compounds from marine algae by molecular docking and assessment of pharmacokinetics. Human norepinephrine transporter (hNET) was used as target for this study as this transporter is responsible to reuptake norepinephrine and disturbs chemical balance of brain, which can be a cause for depression. Binding affinity of these compounds was compared with binding affinity of prescribed drug levomilnacipran. From 14 selected compounds, 13 showed higher binding affinity towards hNET. Among all compounds, saringosterone has highest binding score. Pharmacokinetics properties were constructive for most compounds. Compounds showed weaker druglikeness and drugs score but can be optimized to enhance it. Compounds identified as inhibitors of NET can be developed as drug molecules in future or algal source for it can be taken as a food supplement.

Isolation, fractionation and anticoagulant activity of a sulfated galactan extracted from the green algae Penicillus capitatus / Isolamento, fracionamento e atividade anticoagulante da galactana sulfatada extraída da alga verde Penicillus capitatus

ABSTRACT: Marine algae are natural sources of macromolecules known as sulfated polysaccharides. This class of compounds has attracted the interest of Pharmaceutical Sciences due to its pharmacological anticoagulant, antiplatelet and antithrombotic properties. Therefore, this study evaluated the anticoagulant potential of sulfated polysaccharides extracted from the algae Penicillus capitatus. The extracted sulfated polysaccharides were purified, partially characterized and their anticoagulant activity was evaluated. The extraction process followed by ethanol precipitation resulted in five fractions. Among the analyzed fractions, F44 contained highest concentration of sulfated polysaccharides. After the purified fraction F23, F44 displayed in vitro anticoagulant activity in a time testing for activated partial thromboplastin time and prothrombin time. The preferential mechanism effect was based on interactions between thrombin and factor Xa. Additional studies on structure pharmacological are required to test the viability of the use of sulfated polysaccharides as therapeutic agents.

RESUMO: As algas marinhas são fontes naturais de macromoléculas conhecidas como polissacarídeos sulfatados. Esta classe de compostos atraiu o interesse das Ciências Farmacêuticas devido às suas propriedades farmacológicas como anticoagulante, antiplaquetária e antitrombótica. Portanto, este estudo tem como objetivo avaliar o potencial anticoagulante de polissacarídeos sulfatados extraídos de algas de Penicillus capitatus. Os polissacarídeos sulfatados extraídos foram purificados, parcialmente caracterizados e sua atividade anticoagulante foi avaliada. O processo de extração seguido pela precipitação com etanol resultou em cinco frações. Entre as frações analisadas, F44 foi a maior concentração de polissacarídeos sulfatados. Após a purificação, as frações F23 e F44 mostraram atividade anticoagulante in vitro em um teste de tempo de tromboplastina parcialmente ativada e tempo de protrombina. Seu mecanismo preferencial é baseado nas interações entre trombina e fator Xa. Estudos adicionais sobre a estrutura farmacológica são necessários para testar a viabilidade do uso como agente terapêutico.

Screening Of The Antioxidant Activity Of Crude Extracts In 86 Algae Species From El Jadida Coast (MOROCCO)

Objective: This work aimed to screen the antioxidant activity of marine macroalgae from the Moroccan Atlantic coast (region of El Jadida). Methods: Evaluation of the antioxidant activity of different collected species, lyophilized and extracted with a solvent mixture chloroform/methanol (2/1; v/v) was conducted according to two techniques, first by thin layer chromatography (tlc) then by spectrophotometry, using a free radical 2,2-diphenyl-1-picrylhydrazyl (dpph). The sampling on a distance of 110 km allowed to harvest 86 algal species (16 brown algae, 47 red algae, 14 green algae and 9 algae being identified). Results: The analysis by thin layer chromatography reveals an antioxidant activity in nearly half of harvested algal species (52.32 %). This activity varies depending on the concentration of the extract and in function of incubation time in the presence of dpph. The monitoring of the kinetics of degradation of dpph by spectrophotometer in the presence of extracts which were active by tlc allowed to confirm the results and select the most active algal species based on the percentage of remaining dpph in the medium after 120 min of reaction: Fucus spiralis (17.02 %), Cyctoseira ericoides (12.16 %) (Phaeophyceae), and Gracilaria multipartita (36%), Halopitys incurvus (5%) (Rhodophyceae). Conclusion: The results show that the methodology adopted in this work is reliable and can be used for rapid screening of antioxidant property in plants and the species: Fucus spiralis, Cyctoseira ericoides, Gracilaria multipartita, and Halopitys incurvus can be a promising source of natural compounds endowed with high antioxidant potential.

Extraction, physical-chemical characterization and in vitro inhibitorypotential of thrombin generation of crude sulfated polysaccharides from Brazilian tropical seaweeds / Extração, caracterização físico-química e potencial inibitório in vitro da geração detrombina de polissacarídeos sulfatados brutos de algas marinhas tropicais brasileiras

The biotechnological value of macroalgae for screening assays of thrombin generation-TG using sulfated polysaccharides-SPs as substitutes to heparin has been poorly explored. Five Brazilian species of macroalgae (Gracilaria birdiae, Acanthophora muscoides, Halymenia sp., Caulerpa cupressoides and C. racemosa) wereanalyzed and compared for their abundance, physical-chemical characteristics and in vitro anticoagulant assays of activated partial thromboplastin time-APTT, prothrombin time-PT and TG. Papain extraction yielded (p 100 kDa. These procedures,combined with the use of Stains-All, also indicated nonSPs. APTTs ranged from 2.81 (A. muscoides) to 21.30 IU(Halymenia sp.) vs. heparin (193 IU), and were dependent on sulfation of the crude SPs. PT was not altered. Withrespect to TG assay, crude SPs modified concentration-dependent and independently from molecular mass TGby both intrinsic/extrinsic pathways in 60-fold diluted human plasma, with total intrinsic inactivation using crudeSPs from A. muscoides in parallel to heparin (p < 0.05). Thrombosis in vitro is differentially modulated by distinctcrude SPs from Brazilian seaweeds.

O valor biotecnológico das macroalgas para ensaios de varredura de geração de trombina-GT pouco tem sido explorado usando polissacarídeos sulfatados-PSs como substitutos à heparina. Foramanalisadas e comparadas cinco espécies brasileiras de macroalgas (Gracilaria birdiae, Acanthophora muscoides, Halymenia sp., Caulerpa cupressoides e C. racemosa) quanto à abundância, às característicasfísico-químicas e os ensaios anticoagulantes in vitro de tempo de tromboplastina parcial ativada-TTPA, aotempo de protrombina-TP e a GT. A extração com papaína rendeu (p 100 kDa. Esses procedimentos,combinados ao uso de azul de toluidina/Stains-All, indicaram também polissacarídeos-não sulfatados. OsTTPAs foram dependentes da sulfatação dos PSs brutos e variaram de 2,81 (A. muscoides) a 21,30 UI (Halymenia sp.) vs. heparina (193 UI). O TP não foi alterado. Com respeito ao ensaio de GT, os PSs brutos modificaram, dependente de concentração e independentemente de massa molecular, GT pelas viasintrínseca/extrínseca no plasma humano diluído 60 vezes, com inativação intrínseca total usando PSs brutosde A. muscoides em paralelo à heparina (p < 0,05). A trombose in vitro é modulada diferencialmente porPSs brutos distintos de algas marinhas brasileiras.

In vitro anticancer activity of polysaccharide extracted from red alga Jania rubens against breast and colon cancer cell lines

Objective:To evaluate the potential role of the polysaccharides of the marine algae as an anticancer agent in vitro against colon cancer cell line (CoCa2) and breast cancer (MCF7) cell lines and to measure lactate dehydrogenase enzyme (LDH) activity as biomarker of membrane integrity of the cells.Methods:The cells of breast cancer (MCF7) and colon cancer (CoCa2) were used to evaluate the potential anticancer role of the polysaccharides of marine algae. Anti-proliferative activity against MCF7 and CoCa2 cell lines were evaluated in vitro by the 3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2H-tetrazolium bromide (MTT) assay.Results:The in vitro assay of the antioxidant activity of eight marine seaweed species showed that the red seaweed Jania rubens (J. rubens) had the highest DPPH (2,2 diphenyl-1-picrylhydrazyl) free radical scavenging activity. The extracted polysaccharides with concentrations 0.1–40.0 mg/mL from J. rubens were tested for its anticancer potentiality and cytotoxic effects against the cell lines of human breast (MCF7) and colon cancer (CoCa2) cell lines by MTT assay. The inhibitory concentration at 50 (ICConclusions:The polysaccharides of the red marine alga J. rubens could be a potential candidate for the natural compounds as antioxidant and anticancer therapy.

In vitro anticancer activity of polysaccharide extracted from red alga Jania rubens against breast and colon cancer cell lines

Objective: To evaluate the potential role of the polysaccharides of the marine algae as an anticancer agent in vitro against colon cancer cell line (CoCa2) and breast cancer (MCF7) cell lines and to measure lactate dehydrogenase enzyme (LDH) activity as biomarker of membrane integrity of the cells. Methods: The cells of breast cancer (MCF7) and colon cancer (CoCa2) were used to evaluate the potential anticancer role of the polysaccharides of marine algae. Anti-proliferative activity against MCF7 and CoCa2 cell lines were evaluated in vitro by the 3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2H-tetrazolium bromide (MTT) assay. Results: The in vitro assay of the antioxidant activity of eight marine seaweed species showed that the red seaweed Jania rubens (J. rubens) had the highest DPPH (2,2 diphenyl-1-picrylhydrazyl) free radical scavenging activity. The extracted polysaccharides with concentrations 0.1-40.0 mg/mL from J. rubens were tested for its anticancer potentiality and cytotoxic effects against the cell lines of human breast (MCF7) and colon cancer (CoCa2) cell lines by MTT assay. The inhibitory concentration at 50 (IC

Antioxidant activity of ethyl acetate and methanolic extracts of two marine algae, Nannochloropsis oculata and Gracilaria gracilis - an in vitro assay

ABSTRACT The aim of this study was to evaluate the antioxidant activity of ethyl acetate and methanolic extracts of two marine algae, Nannochloropsis oculata and Gracilaria gracilis. The extracts were assayed for total phenol and flavonoid content, DPPH free radical scavenging capacity, nitric oxide activity, iron chelation activity, and reducing power activity. Total phenol and flavonoid content were found to be high in both algae. Ethyl acetate extracts of both algae were found to exhibit significant antioxidant activity. Ethyl acetate extract of N. oculata exhibited a good capacity for iron chelation, nitrate oxide, and scavenging DPPH free radicals (72.95±2.30, 73.73±1.76, and 39.03±0.97% inhibition at 400 µg mL-1 respectively).

Study on monogalactosylmonoacylglycerol in marine algae (Sargassum fusiforme) / 中草药

Objective To indentify monogalactosylmonoacylglycerol (MGMG) and analyze the chemical characteristics of sn-1 and sn-2 type isomers in Marine TCM Sargassum fusiforme. Methods The MGMG compounds were isolated by multiple chromatography methods and their structures were determined by spectroscopic methods such as NMR and HRESI-MS. The interconversion and chromatography-mass spectrometry feature of MGMG positional isomers were analyzed through HPLC and HPLC-ESI-MS/MS. Results Five MGMGs were isolated from Sargassum fusiforme, and the fatty acyl compositions were stearidonoyl, linolenoyl, arachidoyl, linoleyl, and oleyl. The sn-1 and sn-2 type of MGMG were unstable. The interconversion tended to be sn-1 type rapidly, and kept balanced content at 85:15. The relative retention time of sn-2 type was less than sn-1 type on C18 reverse phase chromatography. The abundant fragment ions of MS/MS were significantly differences. The base peak was [M+Na-Gal]+ (100%), and the peak intensity of [M+Na-RCOOH]+ was always more than 50% from sn-2 type while less than 20% from sn-1 type. Conclusion Five MGMGs were isolated from brown algae for the first time. This was the first report about the interconversion and chromatography-mass spectrometry feature of sn-1 and sn-2 type. It can use to determine the fatty acyl attachment in each MGMG.

Polyphenolic contents and antimicrobial activity of different extracts of Padina boryana Thivy and Enteromorpha sp marine algae.

Marine algae are potential sources of biologically active compounds with antiviral, antimicrobial and anticancer activities. Two species of marine algae, Padina boryana Thivy and Enteromorpha sp were collected from the Red Sea. Both species were extracted with ethanol, acetone, and hexane. The extracts of each sample were examined for, total phenolic, total flavonoid contents and antimicrobial activities. The results showed that solvents with different polarities have various effects on phenolic and flavonoid contents. Among the tested solvents, ethanolic extract of Padina boryana Thivy and Enteromorpha sp showed the highest phenolic content. Results also indicated that the extracts of Padina boryana Thivy showed higher antimicrobial activity compared to Enteromorpha sp. The present study demonstrates that both algae species exhibited excellent antimicrobial properties which may use as natural food preservative for possible application in food for health promotion.

Antinociceptive activity of Sargassum polyceratium and the isolation of its chemical components

Abstract Marine algae have been the focus of important studies over the past fifty years, with a considerable number of components important to chemists and taxonomists having been isolated and characterized. The scientific data available on Sargassum polyceratium are extremely limited. The objective of the present study was to evaluate the antinociceptive activity of an ethanol extract of S. polyceratium and to isolate its components. Intraperitoneal treatment with ethanol extract of S. polyceratium reduced the number of acetic acid-induced writhes and the amount of time spent in paw-licking in the second phase of the formalin test. Ethanol extract of S. polyceratium also reduced the amount of time spent in paw-licking in the glutamate test; however, there was no difference in the reaction time in the hot plate test at any of the doses tested. The chemical components isolated from ethanol extract of S. polyceratium were identified using one- and two-dimensional spectroscopic methods such as infrared spectroscopy, mass spectrometry and 1H and 13C nuclear magnetic resonance spectroscopy. The analytical results were also compared with data obtained in the literature. The following porphyrin derivatives were isolated from S. polyceratium: 132-hydroxy-(132-R)-pheophytin-a, 132-hydroxy-(132-S)-pheophytin-a, pheophytin-a, and the steroid fucosterol. The present results indicate that the ethanol extract of S. polyceratium has antinociceptive activity. In addition, four new substances were isolated from the species evaluated.

Enteromorpha intestinalis Derived Seaweed Liquid Fertilizers as Prospective Biostimulant for Glycine max

ABSTRACT In the present study, the potential of seaweed liquid fertilizer (SLF) of marine algae Enteromorpha intestinalis was evaluated for its effect on seed germination, yield, biochemical parameters and pigment characteristics of Glycine maxE. intestinalis was collected form Mandapam coast of Gulf of Mannar, Tamil Nadu, and the dried seaweeds were used for the preparation of SLF. G. max seeds were germinated with four different concentrations (20, 40, 60, and 100%) of SLF; its growth and yield parameters were evaluated and compared with chemical fertilizer and control. The morphological and bio-chemical parameters such as seed germination (100%), root (6.6cm) and shoot length (5.4 cm), carbohydrates (0.098 mg/g), protein (0.56 mg/g), pigment (0.444 mg/g chl a; 1.073 mg/g chl b; 3.70 mg/g carotenoids) of the plant was found maximum at a concentration of 60% SLF. The phenol content (3.25 mg/g) was maximum in 40% SLF. The GC-MS analysis of SLF revealed the presence of notable benzoic compounds involved in plant growth promotion. Results showed thatE. intestinalis derived SLF was potential biostimulant forG. max. Thus, marine algae based fertilizer could be an effective and alternate to the chemical fertilizers emphasizing the need for systematic evaluation programme for SLF on various crops.

Emerging Novel Anti HIV biomolecules from marine Algae: An overview.

Over the past 3 decades, despite enormous scientific advancements and developments in the field of vaccine development and drugs, HIV-1 is still posing a major challenge to human health. While development of vaccines is still clearly many years ahead, administration of FDA approved drugs leads to severe side effects and toxicity. Marine algae due to its biodiversity has been a rich source of biologically active compounds with varying degree of actions such as anti-viral, anti-cancer, anti-amyloid, anti-inflammatory and anti-oxidant properties. The primary and secondary metabolites obtained from the marine algae have shown potent anti-viral activities in vitro and in animal model. This review focus on the bioactive compounds from marine algae that have been recently identified and studied.

In vitro antimicrobial activities of methanolic extract from marine alga Enteromorpha intestinalis

To extract the bioactive compound from Enteromorpha intestinalis (E. intestinalis) and determine its in vitro antimicrobial activity. Methods: E. intestinalis was extracted by methanol and subjected to antimicrobial screening. The antimicrobial activity was studied by using disc diffusion and broth dilution method. The effect of the extract on the growth profile of the bacterial was also examined via time-kill assay. Microscopy observations using SEM was done to determine the major alterations in the microstructure of methicillin-resistant Staphylococcus aureus (MRSA). Results: The results showed methanolic extract of E. intestinalis exhibited a favourable antimicrobial activity against tested bacteria with produced inhibition zone ranging from 8.0-19.0 mm. However, all the tested fungi and yeast were resistant to the extract treatment. Time kill assay suggested that methanolic extract of E. intestinalis had completely inhibited MRSA growth and also exhibited prolonged antibacterial activity. The main abnormalities noted from the microscopic observations were the structural deterioration in the normal morphology and complete collapsed of the bacteria cells after 36 h of treatment. Conclusions: The significant antibacterial activity shown by crude extract suggested its potential against MRSA infection. The extract may have potential to develop as antibacterial agent in pharmaceutical use.

In vitro antimicrobial activities of methanolic extract from marine alga Enteromorpha intestinalis

OBJECTIVE: To extract the bioactive compound from Enteromorpha intestinalis (E. intestinalis) and determine its in vitro antimicrobial activity. METHODS: E. intestinalis was extracted by methanol and subjected to antimicrobial screening. The antimicrobial activity was studied by using disc diffusion and broth dilution method. The effect of the extract on the growth profile of the bacterial was also examined via time-kill assay. Microscopy observations using SEM was done to determine the major alterations in the microstructure of methicillin-resistant Staphylococcus aureus (MRSA). RESULTS: The results showed methanolic extract of E. intestinalis exhibited a favourable antimicrobial activity against tested bacteria with produced inhibition zone ranging from 8.0 to 19.0 mm. However, all the tested fungi and yeast were resistant to the extract treatment. Time kill assay suggested that methanolic extract of E. intestinalis had completely inhibited MRSA growth and also exhibited prolonged antibacterial activity. The main abnormalities noted from the microscopic observations were the structural deterioration in the normal morphology and complete collapsed of the bacteria cells after 36 h of treatment. CONCLUSIONS: The significant antibacterial activity shown by crude extract suggested its potential against MRSA infection. The extract may have potential to develop as antibacterial agent in pharmaceutical use.

Antiviral activity of extracts from Brazilian seaweeds against herpes simplex virus

Organic extracts of 36 species of marine algae (sixteen species of Rhodophyta, eight species of Ochrophyta and twelve species of Chlorophyta) from seven locations on the Brazilian coast were evaluated for their anti-HSV-1 and anti-HSV-2 activity resistant to Acyclovir (ACV). Activity tests in crude extracts, followed by the identification of the major compounds present, were performed for all species. The chemical profiles of all crude extracts were obtained by ¹H-NMR and 13C-NMR spectroscopy. The percentage of extracts with antiviral activity was higher for HSV-1 (86.1%) than for HSV-2 (55.5%). The green algae Ulva fasciata and Codium decorticatum both showed the highest activity (99.9%) against HSV-1, with triacylglycerols and fatty acids as the major components. The red alga Laurencia dendroidea showed good activity against HSV-1 (97.5%) and the halogenated sesquiterpenes obtusol and (-)-elatol were identified as the major components in the extract. Against HSV-2, the green alga Penicillus capitatus (Chlorophyta) and Stypopodium zonale (Ochrophyta) were the most active (96.0 and 95.8%). Atomaric acid, a meroditerpene, was identified as the major secondary metabolite in the S. zonale extract. These results reinforce the role of seaweeds as important sources of compounds with the potential to enter into the pipeline for development of new drugs against herpes simplex.

Marine natural seaweed products as potential antiviral drugs against Bovine viral diarrhea virus

Bovine viral diarrhea virus (BVDV) is an etiologic agent that causes important economic losses in the world. It is endemic in cattle herds in most parts of the world. The purpose of this study was to evaluate the in vitro cytotoxic effect and antiviral properties of several marine natural products obtained from seaweeds: the indole alkaloid caulerpin (CAV, 1) and three diterpenes: 6-hydroxydichotoma-3,14-diene-1,17-dial (DA, 2), 10,18-diacetoxy-8-hydroxy-2,6-dolabelladiene (DB1, 3) and 8,10,18-trihydroxy-2,6-dolabelladiene (DB3, 4). The screening to evaluate the cytotoxicity of compounds did not show toxic effects to MDBK cells. The antiviral activity of the compounds was measured by the inhibition of the cytopathic effect on infected cells by plaque assay (PA) and EC50 values were calculated for CAV (EC=2,0± 5.8), DA (EC 2,8± 7.7), DB1 (EC 2,0±9.7), and DB3 (EC 2,3±7.4). Acyclovir (EC50 322± 5.9) was used in all experiments as the control standard. Although the results of the antiviral activity suggest that all compounds are promising as antiviral agents against BVDV, the Selectivity Index suggests that DB1 is the safest of the compounds tested.

Marine natural products: chemical and biological potential of seaweeds and their endophytic fungi

Marine natural products have currently been recognized as the most promising source of bioactive substances for drug discovery research. In this review, extraordinary metabolites from marine algae species are illustrated, as well as approaches for their isolation and determination of their biological properties and pharmaceutical potential. Furthermore, marine endophytic microorganisms (from marine algae) are presented as a new subject for extensive investigation to find novel natural products, which make them a potentially rich and innovative source for new drug candidates.

Anticoagulant activity of a sulfated polysaccharide isolated from the green seaweed Caulerpa cupressoides

The aim of this study was to evaluate certain molecular characteristics of a sulfated polysaccharide (SPs) with anticoagulant properties, isolated from Caulerpa cupressoides (Chlorophyta). Crude SPs were extracted by proteolytic digestion (papain), followed by ion-exchange chromatography on a DEAE-cellulose column. The fractions obtained were analyzed for molecular mass, 0.5 percent agarose gel electrophoresis and chemical composition. The activated partial thromboplastin time (APTT) test was applied using normal human plasma and standard heparin (HEP) (193 IU mg-1). The yield was ~ 3 percent, and the chromatography procedure separated the material into three different SP fractions (F I, F II and F III), eluted at the concentrations of 0.50, 0.75 and 1.00 M of NaCl, respectively. Only fraction F II was active (24.62 IU mg-1), with high sulfate content (23.79 percent) and number of molecular mass peaks. Therefore, the APTT of a fraction isolated from C. cupressoides was less potent than HEP.

Sulfated fucan from marine alga inhibits HeLa cells infection by HTLV-1 free particles: semi-quantitative analysis

A sulfated fucan from Laminaria abyssalis marine alga prevented the interaction of HTLV-1 particles, purified from the MT-2 cell line, with HeLa cells. The infection obtained using a concentrated virus suspension was detected only by amplification of the newly synthesized HTLV-1 proviral cDNA by the nested-polymerase chain reaction (PCR). The sulfated polysaccharide was not toxic to the cells at a concentration of 100 µg/mL and prevented infection by the viral particles when added to the cell monolayers. The proviral cDNA was only detected when the sulfated polysaccharide was added to the cells three hours post-infection, indicating that the inhibitory activity occurred in the initial stages of virus-cell interaction. Our results demonstrate, for the first time, the ability of a sulfated fucan from marine algae to inhibit virus transmission through free virus particles.

The marine algae Sargassum spp. (Sargassaceae) as feed for sheep in tropical and subtropical regions

The objective of this study was to evaluate Sargassum meal as feed for sheep through the measures of in vivo digestibility, dry matter degradability, pH, ammonia and volatile fatty acids in rumen. The Sargassum algae used in this experiment were collected at the end of spring, when they are more abundant, bigger, and have completed their reproductive cycle. Four tons (wet weigth) were collected manually from the intertidal zone of La Paz bay, Baja California Sur, Mexico. These algae were sun-dried and ground in a hammer mill to obtain the Sargassum meal. Four fistulated Pelibuey sheep, were fed daily with diets containing the marine algae (MA) at different levels (0, 10, 20 and 30 %), using a 4 x 4 Latin-square design experiment. Feed intake was not affected (p>0.05). Water consumption and urine excretion increased with MA (p<0.05; r²=0.54 and r²=0.74, respectively). In all treatments dry matter digestibility was of 74%-79%, and crude protein digestibility was of 85%-88%. Acid detergent fiber (59%-65%) and neutral detergent fiber (55%-66%) digestibility were greater in all treatments with MA. Ruminal pH was greater in all groups fed with MA (p<0.05). Ammonium concentration was not influenced (p>0.05) by MA. Ruminal volatile fatty acids decreased in all MA groups (p<0.05). The marine algae Sargassum spp. can be used as a feed supplement for sheep, especially in tropical and subtropical regions where these marine algae are available. Rev. Biol. Trop. 57 (4): 1271-1281. Epub 2009 December 01.

El objetivo de este estudio fue evaluar la harina del alga marina Sargassum como alimento para ovejas, midiendo la digestibilidad in vivo, la degradabilidad de la materia seca, así como el pH y los ácidos grasos volátiles en rumen. El alga Sargassum utilizada en este experimento, fue recolectada a finales de la primavera, cuando esta alga es más abundante, alcanza su mayor talla y ha completado su ciclo reproductivo. Se recolectaron manualmente, cuatro toneladas (peso húmedo) de la zona intermareal en la Bahía de La Paz, Baja California Sur, México. Estas algas fueron secadas directamente al sol y molidas en un molino de martillos, para obtener la harina. Se utilizaron cuatro borregos Pelibuey fistulados, distribuidos en un arreglo factorial de 4 x 4. Los animales fueron alimentados diariamente con dietas que contenían el alga marina (AM) Sargassum a diferentes niveles (0, 10, 20 y 30%). El consumo de alimento no se vio afectado con la inclusión del alga (p> 0.05). El consumo de agua y la excreción de orina se incrementaron conforme aumentó la concentración de AM en las dietas (p<0.05; r²=0.54 and r²=0.74, respectivamente). En todos los tratamientos la digestibilidad de la materia seca fue de 74% a 79%, la digestibilidad de la proteína cruda fue de 85% a 88%. La digestibilidad de la fibra ácido detergente (59%-65%) y de la neutro detergente (55%-66%) fue mayor en todos los tratamientos con AM, lo mismo ocurrió con el pH en rumen (p<0.05). La concentración de amonio en rumen no se vio afectada por AM (p>0.05). La concentración de ácidos grasos volátiles se redujo en todos los tratamientos con AM (p<0.05). El alga marina Sargassum spp. puede ser usada como complemento alimenticio para ovejas, especialmente en las regiones tropicales y subtropicales donde está disponible.