Tropical Atlantic marine macroalgae with bioactivity against virulent and antibiotic resistant Vibrio

Abstract

ABSTRACT. The antibacterial activity of ethanol, methanol, hexane and acetone-based extracts of the macroalgae Padina gymnospora (PG), Hypnea musciformes (HM), Ulva fasciata (UF) and Caulerpa prolifera (CP) was investigated. The disk diffusion method was used to evaluate the algae antimicrobial effect against standard strains of Vibrio parahaemolyticus, Escherichia coli, Staphylococcus aureus, Pseudomonas aeruginosa and Salmonella enterica and five virulent antibiotic-resistant strains of V. brasiliensis, V. xuii and V. navarrensis (isolated from the hemolymph of Litopenaeus vannamei). Ethanol extracts of PG and HM inhibited all Vibrio strains. E. coli and P. aeruginosa were only susceptible to ethanol extracts of PG. Among the methanol extracts, only UF was bioactive, inhibiting V. navarrensis. The observed inhibitory effect of ethanol extracts of PG, HM and UF against virulent antibiotic-resistant bacteria suggests these macroalgal species constitute a potential source of bioactive compounds.

Water quality,Vibriodensity and growth of Pacific white shrimpLitopenaeus vannamei(Boone) in an integrated biofloc system with red seaweedGracilaria birdiae(Greville)

“…In addition, NO 3 -N was the main form of inorganic nitrogen in the tanks, followed by NO 2 -N and TAN which facilitates its removal, since NO 3 -N and NH 4 + are the main forms of inor-ganic nitrogen removed by red seaweed (Abreu, Pereira, Buschmann, Sousa-Pinto & Yarish 2011). Higher concentrations of NO 3 -N in a biofloc system, as compared to NO 2 -N and TAN, were also observed by Silva, Costa, Peixoto, Nascimento and Carneiro (2013) and Xu and Pan (2014), thus indicating that nitrifying bacteria were also present in the bioflocs, probably due to the lower utilization of NO 3 -N by microbial communities. The TAN and NO 2 -N removal by Gracilaria in water with zero exchange has been shown to depend on the photoperiod (16:8 light/dark for TAN and 14:10 light/dark NO 2 -N), and the biomass ratio of shrimp:seaweed of 1:8 (S anchez- Romero et al 2013).…”

“…However, the presence of seaweed (2.5 and 5.0 kg wet weight m À3 ) in shrimp biofloc systems reduced Vibrio density (by 54-83%). Seaweed has bioactive compounds such as: b-glucan, carotenoids, tocopherols, polyphenols, polysaccharides that can act as antioxidants and promote bioactivity against virulent and antibiotic resistant Vibrio (Peso-Echarri, Frontela-Saseta, Gonz alez-Berm udez, Ros-Berruezo & Mart ınez-Garci a 2012; Silva, Costa et al 2013). These compounds enhance the shrimps' defence mechanisms by increasing the haemocyte and granulocyte counts, and by increasing the activity of phenoloxidase and superoxide dismutase, which decreases mortality rates from viral and Vibrio diseases (Huynh, Yeh, Lin, Shyn, Chen & Chen 2011;Kanjana, Radtanatip, Asuvapongratana, Withyachummarnkul & Wongprasert 2011;Sirirustananun, Chen, Lin, Yeh, Liou, Chen, Sim & Chiew 2011).…”

Effect of Red Seaweed Kappaphycus alvarezii on Growth, Survival, and Disease Resistance of Pacific White Shrimp Litopenaeus vannamei Against Vibrio harveyi in the Nursery Phase

“…We hypothesized that the barrier failed to prevent bacteria or their toxin for entering the gut and eventually infiltrate to hepatopancreas leading to massive sloughing of the tubules. One study has postulated that several compunds, such as protein from lectin family of Gracilaria fischeri may opsonize the bacterial surface causing decrease of colonization of bacteria; thus, reducing the production of bacterial toxins that can damage hepatopancreas [19][20][21][22][23]. Another study suggests that red seaweed %powder could prevent the infection by Vibrio by stimulating the immune system [14].…”

Minireview: algal natural compounds and extracts as antifoulants

“…PHE Diterpenes, glicerol derivatives AB, AF France Othmani et al 2014 Dictyota fasciola PHE Dichloromethane and methanol extract AA, AB, AMF Tunisia Ktari et al 2010 Dictyosphaeria ocellata CHL Methanol extract AB, ABF USA Sneed and Pohnert 2011a , b Fucus vesiculosus PHE Fucoxanthin 3 , dimethyl sulphopropionate 4 , proline 5 AB, ABF Germany Saha et al 2011 , 2012 , Wahl et al 2010 , Lachnit et al 2013 Gracilaria edulis RHO Isoamyl alcohol extract AB India Rajan et al 2015 Hypnea musciformes RHO Ethanol and methanol extracts AB Brazil Silva et al 2013 Laurencia johnstonii RHO Ethly ether extract AA, AB, AF Mexico Águila-Ramírez et al 2012 Laurencia sp. RHO Omaezallene 6 intricatetraol 7 AMF Japan Umezawa et al 2014 Laurencia translucida RHO Fatty acid derivatives AMF Brazil Paradas et al 2016 Laurencia viridis RHO 28-Hydroxysaiyacenol B Saiyacenol C 15,16-epoxythyrsiferol A 15,16-Epoxythyrsiferol B AMF Spain Cen-Pacheco et al 2015 Padina gymnospora PHE Ethanol and methanol extracts AB Brazil Silva et al …”