Biopotency of Avicennia marina leaf extracts against pathogenic bacteria in carp culture

Abstract

Disease emergence has become a main limiting factor in aquaculture. The massive application of antibiotics as disease therapy has been resulting in the adverse effects of environment, host and consumers. Ethyl acetate leaf extract of A.marina has recorded high biological activity. Crude extract has showed the antibacterial activity of range 3.2 ± 0.8 mm against B.subtilis to 5.7 ± 0.7 mm against A.hydrophila, DPPH; 15.9 ± 0.7 AAE µg/ml to 79.4 ± 1.0 AAE µg/ml and FRAP; 6.4 ± 1.3 AAE µg/ml to 127.3 ± 1.3 AAE µg/ml. The mass spectral results revealed the presence of thioacetic acid, methyl thio ethane, 1-Fluoro-2-propanone, Isopropanethiol. CAT and SOD levels of ethyl acetate extract treated fingerlings was: crude; 15.5 ± 1.0 units/mg of protein and 13 ± 0.9 units/mg of protein, purified 18.3 ± 0.5 units/mg of protein and 16.9 ± 1.1 units/mg of protein.

Keywords: Avicennia marina; Antibacterial activity; Antioxidant activity; Phytocompounds.

Fig. 1

Correlation between TPC, TFC and antioxidant activity of ethyl acetate leaf extract of A.marina A TPC vs. DPPH, B TPC vs. FRAP, C TFC vs. DPPH and D TFC vs. FRAP

Fig. 2

LC-MS chromatogram of A.marina crude ethyl acetate leaf extract

Fig. 3

A-D GC-MS chromatogram of band AE1, ethyl acetate leaf extract of A.marina

Fig. 4

Histopathology of Control (Group A). A Gill- GL: Gill lamellae, GC: Gill Cartilage, A: Artery, GA: Gill Arch. A.1 showing GL, GA, A and GC, B Muscle- M: Muscle bundle, IMS: Inter Muscle bundle Space, C Liver- V: Vein, H: Hepatocytes, N: Nucleus, MC: Macrophage Centre. C.1 showing H and N, D Kidney- G: Glomerulus, HT: Haemopoetic Tissue, IW: Inner Wall, OW: Outer Wall, BC: Bowman’s capsule, E Intestine- MF: Mucosal Folds, M: Mucosa, SM: Sub Mucosa, S: Serosa, M: Muscularis. (A-D, C1: 400X, E and A1: 100X)

Fig. 5

Histopathology of Negative control (Group B). A Gill- GLF: Gill lamellae Fusion, IGC: Inflammation in Gill Cartilage, GN: Gill Necrosis. B Muscle- IIMS: Increased and Irregular Inter Muscle Space, CDM: Cellular Degeneration in Miuscle bundle, IMB: Irregular Muscle Bundle, DM: Degeneration in Muscle bundle. C Liver- V: Vacuoles, ID: Intracellular Deposits, HN: Hepatic Necrosis. D Kidney- HTN: Haemopoetic Tissue Necrosis, SS: Sinusoidal Space, GN: Glomerular Necrosis, GV: Glomerular Vacuolation. E Intestine- NDL: Necrotic Debris in Lumen, NVE: Necrosis in Villus Epithelium, DSM: Degeneration in Sub Mucosa, E1 showing S: Serosa, M: Muscularis, SM: Sub Mucosa, DSM. (A-E: 400X, E.1: 100X)

Fig. 6

Histopathology of Positive control (Group C). A Gill- GLF: Gill lamellae Fusion, GN: Gill Necrosis, A: Artery, GA: Gill Arch. B Muscle- IMS: Inter Muscle bundle Space, M: Muscle bundle. C Liver- DH: Slight Degeneration in Hepatocytes, GH: Granulation in Hepatocytes. D Kidney- HT: Haemopoetic Tissue, G: Glomerulus, OW: Outer Wall, IW: Inner Wall, BC: Bowman’s Capsule. E Intestine- MF: Mucosal Fold, Mu: Mucosa, SM: Sub Mucosa, M: Muscularis, S: Serosa (A:100X, B-E: 400X)

Fig. 7

Histopathology of fingerlings infected and treated with crude A.marina (Group D). A Gill- GL: Gill Lamellae, GC: Gill Cartilage. B Muscle- IMS: Inter Muscle bundle Space, M: Muscle bundle. C Liver- H: Hepatocytes, N: Nucleus. D Kidney- HT: Haemopoetic Tissue, G: Glomerulus, OW: Outer Wall, IW: Inner Wall, BC: Bowman’s Capsule. E Intestine- MF: Mucosal Fold, NDL: Necrotic Debris in Lumen (A-E: 400X)

Fig. 8

Histopathology of fingerlings infected and treated with purified A.marina (Group E). A Gill- GL: Gill Lamellae, GC: Gill Cartilage. B Muscle- IMS: Inter Muscle bundle Space, M: Muscle bundle. C Liver- H: Hepatocytes, N: Nucleus. D Kidney- HT: Haemopoetic Tissue, G: Glomerulus, OW: Outer Wall, IW: Inner Wall, BC: Bowman’s Capsule. E Intestine- MF: Mucosal Fold, Mu: Mucosa, SM: Sub Mucosa (A-E: 400X)