Antimicrobial activity of Tetradenia riparialeaf essential oil / Actividad antimicrobiana del aceite esencial de hoja de Tetradenia riparia

Food spoilage is a widely neglected problem and the constant use of synthetic fungicides could develop resistant fungi. The objective of this study was to evaluate the chemical composition and antimicrobial activity of Tetradenia riparialeaf essential oil against foodborne disease microorganisms. Leaf essential oil was obtained by hydrodistillation and identified by gas chromatography coupled to mass spectrometry. The antimicrobial activity was studied by broth microdilution. The major compounds identified were oxygenated sesquiterpenes (43.6%): 14-hydroxy-9-epi-(E)-cariophylene (20.8%) and τ-cadinol (18.4%); followed by oxygenated diterpenes (24.6%): 6,7-dehydroroyleanone (12.6%) and 9ß, 13ß-epoxy-7-abiethene (10.6%); sesquiterpenic hydrocarbons (17.1%) and oxygenated monoterpenes (7.4%): fenchone (5.6%). The essential oil had broad antibacterial and antifungal activity, mainly against A. versicolor and P. ochrochloron with fungistatic and fungicidal activities and B. cereus, L. monocytogenes, and S. aureuswith bacteriostatic and bactericidal activities. T. riparialeaf essential oil is a potential alternative to control microorganisms-

El deterioro de los alimentos es un problema ampliamente desatendido y el uso constante de fungicidas sintéticos podría desarrollar hongos resistentes. El objetivo de este estudio fue evaluar la composición química y la actividad antimicrobiana del aceite esencial de hoja de Tetradenia riparia contra microorganismos patógenos transmitidos por los alimentos. El aceite esencial de hoja se obtuvo por hidrodestilación y se identificó mediante cromatografía de gases acoplada a espectrometría de masas. La actividad antimicrobiana estudiada fue por microdilución en caldo. Los compuestos principales del aceite esencial se identificaron como sesquiterpenos oxigenados (43,6%): 14-hidroxi-9-epi-(E)-cariofileno (20,8%) y τ-cadinol (18,4%); seguido de diterpenos oxigenados (24,6%): 6-7-deshidroroileanona (12,6%) y 9ß, 13ß-epoxi-7-abieteno (10,6%); hidrocarburos sesquiterpénicos (17,1%) y monoterpenos oxigenados (7,4%): fenchona (5,6%). Tenía amplia actividad antibacteriana y antifúngica, principalmente contra A. versicolor y P. ochrochloron con actividades fungistáticas y fungicidas, y principalmente contra B. cereus, L. monocytogenes y S. aureus con actividades bacteriostáticas y bactericidas. El aceite esencial de hoja de T. riparia es una alternativa potencial para controlar microorganismos.

Chemical analysis, antifungal and antimycotoxigenic activity of tetradenia riparia essential oil and crude extract.

Tetradenia riparia is known for its richness in essential oil which has been widely investigated due to its biological activities such as antimicrobial, insecticidal, trypanocidal, antimalarial and antioxidant. The objective of this work was to chemically analyze and evaluate the antifungal and antimycotoxigenic activity of the essential oil and the crude extract of leaves, flower buds and stems of T. riparia from the northwest region of the state of Paraná. The essential oil was obtained by hydrodistillation using a Clevenger-type apparatus. To obtain the crude extract, the leaves, flower buds and stems were pulverized and subjected to a dynamic maceration process using 70% v v-1 ethyl alcohol. Chemical analysis of the essential oil was performed by GC/MS, and chemical identification of the crude extract by UHPLC-ESI/qTOF. Antifungal activity (Rhizopus oryzae, Aspergillus flavus, Aspergillus ochraceus, Penicillium verrucosum and Fusarium graminearum) was performed by broth microdilution and the antimycotoxigenic assay was performed with A. ochraceus and P. verrucosum. Ochratoxin A was extracted by partition with chloroform and quantified by HPLC-FL. The oil yield was 0.29% for leaves, 0.34% for stems and 0.38% for flower buds, and the major compounds were fenchone, ß-caryophyllene, α-cadinol, 14-hydroxy-9- epi-caryophyllene, 9ß,13ß-epoxy-7-abietene, α-cadinol and 6-7-dehydroroyleanone. The main chemical compounds identified in the crude extract were terpenes, anthocyanins, flavonoids, tannins and phenolic acids. The minimum inhibitory concentration (MIC) of oils from leaves, flower buds and stems for the strains tested ranged from 0.87 mg mL-1 to 33.3 mg mL-1, while the minimum fungicidal concentration (MFC) ranged from 6.94 mg mL-1 and 33.3 mg mL-1. The MIC and MFC for ketoconazole, tebuconazole, sorbate and nitrite ranged from 0.05 to 33.3 mg mL-1. The oil and crude extract of leaves, stems and flower buds showed an inhibition of ochratoxin A production for P. verrucosum of approximately 100%.

Safflower seed supplementation in lamb feed: effects upon fatty acid profile and quality of meat patty formulations.

The aims of this study were to determine the fatty acid profile of meat from lambs fed with different levels of safflower seed (0%, 7.5%, and 15%) and, also, to compare the characteristics of the meat patties prepared from this lamb meat (LMP) with beef meat patties (BMP). The safflower seed-supplemented diet did not change the contents of polyunsaturated and unsaturated fatty acids, except for C22:1. All meat patty formulations were considered safe for consumption. The values of cooking yield, shrinkage, water absorption index, luminosity (L*), and redness (a*) were similar for the LMP and BMP tested. While the safflower seed-supplemented diet did not alter the moisture, ash, and protein levels of LMP, the lipid content was lower than that in BMP. The incorporation of 15% safflower seed into lamb feed contributed to promoting better sensory attributes of the meat patties. Most of the physicochemical properties evaluated were similar among LMP and BMP. However, to improve the sensory properties of the product, dietary supplementation with 15% safflower seed is recommended.