Chemical Characterization and Antibacterial Properties of Fontitrygon margarita (Günther, 1870) Liver Oil

Abstract

Objective. The aim of this study was to determine the chemical characteristics and antibacterial activity of Fontitrygon margarita liver oil against the bacteria responsible for food poisoning. Methods. Oils were extracted from F. margarita liver using two methods (exudation and cooking-pressing) and analyses by Fourier transform infrared (FTIR) spectroscopy. Quality indexes were determined using standard methods and the fatty acid profile was carried out by gas chromatography with a flame ionization detector (GC-FID). Antibacterial activities of these oils, their emulsion, and their interactions with common antibiotics were evaluated by the broth microdilution method. Results. Extraction yield was higher with cooking-pressing (16.90%) compared to exudation (14.49%). The quality indexes of both oils were conformed to Codex Alimentarius Standard. Thiobarbituric acid index was higher with exudation compared to cooking-pressing (3.20 ± 0.14 and 2.36 ± 0.14 μmol MDA/kg, respectively) while acid, iodine, peroxide, and anisidine values did not significantly vary with the extraction methods (2.15-2.30 mgKOH/g, 102.42-106.65 gI2/100 g, 3.34-3.57 meqO2/kg, and 2.85-3.32 respectively). FTIR analyses clearly show that the two spectra are similar (no differences in the frequency and absorbance of their bands). The fatty acid profile revealed that, regardless of the extraction methods, F. margarita oil is richer in monounsaturated (55.97-55.41%) followed by polyunsaturated (28.17-28.52%) and saturated fatty acids (15.86-16.07%). Moreover, these oils showed antibacterial activity on all the bacteria strains tested with MICs between 16 and 256 mg/ml. Regardless of the extraction methods, emulsions showed higher activity (6.25 ≤ MIC ≤25 mg/ml) compared to crude oils. Additionally, F. margarita liver oil potentiated the antibacterial activity of ciprofloxacin, tetracycline, gentamicin, amoxicillin, and chloramphenicol. Conclusion. These results showed the effectiveness of Fontitrygon margarita liver oil against some bacteria responsible for food poisoning, thus demonstrating their antibacterial properties which could be due to their chemical composition.

Physicochemical Characteristics and Nutritional and Biological Properties of Fish Oils in Cameroon: An Overview

“…Simo et al also found that oil from F. margarita liver had activity against bacteria responsible for food-borne illnesses, with exudation-obtained oil being more active than cooking-pressed oil. Furthermore, the nanoemulsion of this oil exhibited better activity than the crude oil [21]. Te antimicrobial activity of these oils could be explained by the presence of signifcant amounts of PUFA including DHA, EPA, linolenic acid, arachidonic acid, palmitoleic acid, and oleic acid [35].…”

“…In the study conducted by Manz Koule et al [28] on Ethmalosa fmbriata fllet, the Bligh and Dyer method was used to extract oil, which showed low SaV (96.04 mgKOH/g) compared to standards but respected the standards for AcV (1.04 mgKOG/g), TaV (1.13 µmol MDA/kg), PeV (1.28 meqO 2 /kg), and AnV (0.76). Noutsa et al [21] extracted oils from Fontitrygon margarita liver using cooking-pressing and exudation methods and achieved results that were within the standards for AcV (2.15-2.30 mgKOH/mg), TaV (2.36-3.20 µmol MDA/kg), PeV (3.34-3.57 meqO 2 /kg), AnV (2.85-3.32), and Totox value (9.04-10.21) for both methods. Te IiV did not signifcantly vary according to the extraction method (102.42-106.65 g I 2 /100 g).…”

“…In 2021, four studies were conducted: Dama et al researched the composition of P. elongatus, P. senegalensis, and P. typus from Youpwe [23]; Christophe Manzkoule et al studied the chemical characteristics of oils from I. africana and Sardinella maderensis from the Douala fshing port [24]; and Ndômbôl et al conducted two studies on the chemical characteristics of oils from fsh by-products collected at Douala markets [25,26]; Njiké Ngamga et al studied the antibacterial activity of oil from of Chrysichthys nigrodigitatus [27]. In 2022, two studies were available: Noutsa et al researched the chemical characteristics, fatty acid profle, and antibacterial activity of oil from Fontitrygon margarita collected in Youpwe [21]; and Tenyang et al conducted research on the chemical characteristics of oil from Polypterus bichir bichir collected at the Maga fsh market in July Te other places of sampling were the Maga fsh market for four studies and Batié for two studies. Oils were mostly extracted from fsh flets (21 studies), with the remaining samples obtained from by-products such as adipose tissue, liver, viscera, and gills.…”

“…For Ethmalosa fmbriata flet, Manz Koule et al noted an oil extraction yield of 2.79% WW, which was obtained using the Bligh and Dyer method [28]. Simo et al obtained an oil extraction yield of 14.49% WW with cooking-pressing and 16.90% WW with exudation for the liver of Fontitrygon margarita [21]. Tenyang et al obtained an oil content of 5.52% DM from the flet of Heterotis niloticus with the Soxhlet method [42], while Cristelle et al obtained an oil content of 4.20% DM with the Bligh and Dyer method [37,43].…”

“…Chrysichthys nigrodigitatus Evaluation of In vivo activity of diferent diets formulated with boiled fsh oils, oil + amoxicillin and boiled fsh was evaluated on rat-induced Salmonella typhi infection Diets formulated with fsh oils or fesh: [27] (i) Healed the infected rats between the 16 th and 18 th day (ii) Combined with the antibiotic resulted in a rapid and complete recovery (iii) Normalized the levels of red blood and white blood cells Evaluation by the broth microdilution method of activity of oil against eight bacteria responsible for food poisoning diseases Oil extracted by cooking-pressing was active on six bacteria of the eight tested while that obtained by maceration was active on only four bacteria [35] Fontitrygon margarita Evaluation by the broth microdilution method of activity of oil and its nanoemulsion against some bacteria responsible for food poisoning; and study of interaction of oil with common antibiotics (i) Oils exhibited antibacterial against most of the bacterial tested [21] (ii) Oil obtained by exudation was more active than that obtained by cooking-pressing (iii) Nanoemulsion of oils showed better activity compared to oil (iv) Oils potentiated activity of some antibiotics Hepsetus odoe Evaluation by the broth microdilution method of activity of oil against eight bacteria responsible for food poisoning diseases Oil was active on seven of the eight tested bacteria [35] Lutjanus dentatus Evaluation by the broth microdilution method of activity of oil and its nanoemulsion against some bacteria responsible for food poisoning; and study of interaction of oil with common antibiotics (i) Oils exhibited antibacterial activity against most of the bacterial tested [30] (ii) Oil obtained by cooking-pressing was more active than that obtained by drying-pressing (iii) Nanoemulsion showed better activity compared to oil (iv) Oils potentiated activity of some antibiotics reduced weight and dyslipidemia in obese rats [39]. [35].…”