Potential of indigenous plants seed extracts of Anisophyllea boehmii and Aframomum sanguineum from Burundi to protect against oil oxidation / Potencial de extratos de sementes em plantas indígenas de Anisophyllea boehmii e Aframomum sanguineum do Burundi para a proteção contra a oxidação de óleo

The objective of seed extracts from Anisophyllea boehmii and Aframomum sanguineum were to evaluate their ability to stabilize against oxidation of oils exposed to sunlight on one hand and subjected to high temperatures on the other hand. Determination of the peroxide value (PV) showed that the extracts had reduced the oxidation of sunflower oils. After 8 weeks of sunlight exposure, the concentration of 265.45 mg/l of A. boehmii extract showed a PV of 30.78 meq O2/kg, 67.4 mg/l extract of A. sanguineum had a PV of 42.75 meq O2/kg while the oils without extracts had a very high PV (125.06 meq O2/kg). Heating of the oils to 180°C for 8 hours was found, with A. boehmii extract (265.45 mg/l), to have a PV of 29.66 meq O2/kg, with that of A. sanguineum, while the PV of the oils without extract reached 50.66 meq O2/kg. In the light of these results, the seeds of A. boehmii and A. sanguineum contain antioxydant compounds, which, once extracted, can be used for many purposes in the food processing, pharmaceutical and cosmetic industries.

O objetivo da extração de sementes de Anisophyllea boehmii e Aframomum sanguineum foi avaliar sua capacidade de estabilização contra a oxidação de óleos expostos à luz solar, por um lado, e submetidos a altas temperaturas, por outro. A determinação do valor de peróxido (VP) mostrou que os extratos tinham reduzido a oxidação dos óleos de girassol. Após 8 semanas de exposição à luz solar, a concentração de 265,45 mg/l de extrato de A. boehmii mostrou um VP de 30,78 ppm O2/kg, 67,4 mg/l de extrato de A. sanguineum tinha um VP de 42,75 ppm O2/kg enquanto os óleos sem extratos tinham um VP muito alto (125,06 ppm O2/kg). Aquecimento dos óleos a 180 °C por 8 horas foi obtido com extrato de A. boehmii (265,45 mg/l), para obtenção de um VP de 29,66 ppm O2/kg, com o de A. sanguineum, enquanto o VP dos óleos sem extrato atingiu 50,66 ppm O2/kg. A partir desses resultados, pode-se afirmar que as sementes de A. boehmii e A. sanguineum contêm compostos antioxidantes que, uma vez extraídos, podem ser utilizados para diversos fins nas indústrias de processamento de alimentos, farmacêutica e cosmética.

Antibiotic resistance profile of gram-negative bacteria isolated from dog nasal swab samples, and antibacterial and antioxidant activities of aqueous extracts of Alpinia purpurta (Vieill.) K. Schum (Zingiberaceae) / Perfil de resistência a antibióticos de bactérias gramnegativas isoladas de amostras de swab nasal de cães e atividades antibacteriana e antioxidante de extratos aquosos de Alpinia purpurta (Vieill.) K. Schum. (Zingiberaceae)

The indiscriminate use of antibiotics in veterinary medicine and their negligent use among dog owners have contributed to the rise of antibiotic resistance in microorganisms found in pets. In addition, the search for medicinal plants with antibacterial properties has made the evaluation of aqueous extracts of Alpinia purpurata (Vieill.) K. Schum an important issue. Thus, the aim of this work was to determine the antibiotic resistance profile of gram-negative bacteria isolated from nasal swab samples of dogs and assess the antibacterial activity of the aqueous extracts of leaves and rhizomes of A. purpurata. The bacteria identified were tested using the agar disc diffusion assay for the evaluation of antibiotic resistance. A total of 16 isolates were obtained from the 19 samples collected, with a high prevalence of Escherichia coli (n=5). There was a high rate of resistance to ß-lactams, where the highest percentage was seen for amoxicillin (72.5%). Aqueous leaf extracts had high levels of total phenolic compounds (637.47 µg GAE mg-1), differing significantly (p < 0.05) from aqueous rhizome extracts (228.64 µg GAE mg-1). There was no significant difference in EC50 of DPPH values between the aqueous extracts; however, the antioxidant capacity of rhizome extracts had higher values than leaf extracts. The minimum inhibitory concentration (MIC) of leaves and rhizomes for the evaluated bacteria ranged from 9000 to 32,000 µg mL-1. For the minimum bactericidal concentration (MBC), most bacteria showed an MBC over 38,400 µg mL-1 for the rhizome. In conclusion, the bacteria isolated from dog nasal swabs showed a high resistance profile for the antibiotics of the penicillin class. Additionally, the results from the analysis of the aqueous extracts of rhizomes and leaves of A. purpurata showed an antimicrobial effect possibly associated with a high content of total phenolic compounds; these results can create a scope for using these extracts together with conventional antibiotics to control the emergence of antibiotic resistance among microbial species.(AU)

O uso indiscriminado de antibióticos na Medicina Veterinária e negligência de tutores de cães no uso adequado contribuíram no aumento de resistência em animais de companhia. Além disso, a busca por plantas medicinais que tenham efeito antibacteriano tornou importante a avaliação de extratos aquosos de Alpinia purpurata (Vieill.) K. Schum. Dessa forma, o objetivo do trabalho foi determinar o perfil de resistência aos antibióticos de bactérias Gram-negativas isoladas de amostras de swabs nasais de cães e verificar a atividade antibacteriana dos extratos aquosos das folhas e dos rizomas de A. purpurata. As bactérias identificadas foram submetidas à técnica de disco difusão em ágar para avaliação da resistência aos antibióticos. Das 19 amostras colhidas, foram isoladas 16 bactérias, com maior prevalência para Escherichia coli (n=5). Verificou-se um alto índice de resistência aos ß-lactâmicos testados, com maior percentual para amoxicilina (72,5%). Os extratos aquosos das folhas apresentam elevados teores de compostos fenólicos totais (637,47 µg GAE mg-1 extrato), sendo diferente (p < 0,05) dos extratos aquosos dos rizomas (228,64 µg GAE mg-1 extrato). Não houve diferença significativa nos valores de EC50 ­ DPPH para os extratos aquosos, entretanto, para a capacidade antioxidante FRAP, os extratos dos rizomas de A. purpurata demonstraram maiores valores quando comparados com os extratos aquosos das folhas. A Concentração Inibitória Mínima (CIM) das folhas e rizomas para as bactérias avaliadas variaram entre 9.000 a 32.000 µg mL-1. Para a Concentração Bactericida Mínima (CBM), a maioria das bactérias apresentaram CBM acima de 38.400 µg mL-1 para o rizoma. Conclui-se que as bactérias isoladas de swab nasal de cães apresentam alto perfil de resistência aos antibióticos da classe das penicilinas, no entanto, os resultados dos extratos aquosos dos rizomas e das folhas de A. purpurata sinalizam efeito antimicrobiano possivelmente associado ao elevado teor de compostos fenólicos totais, podendo ser utilizado em conjunto aos antibióticos convencionais, reduzindo assim sua resistência.(AU)

Forecasting the impact of an invasive macrophyte species in the littoral zone through aquatic insect species composition

Invasive macrophytes threaten freshwater ecosystem biodiversity. We analyzed the impact of the invasive white ginger lily (Hedychium coronarium J. Kõnig, Zingiberaceae) on aquatic insect assemblages living in the littoral zone of a tropical reservoir. We took aquatic insect samples in the littoral zone on four main vegetal profile banks: white ginger monotypic bank, forest partially invaded, native macrophyte monotypic bank and riparian forest. At each vegetal bank, we measured abiotic variables such as dissolved oxygen, pH, water temperature and depth. We analyzed the aquatic insects through abundance, richness and Simpson diversity. We used the non-Metric Multidimensional Scaling (nMDS) analysis to analyze the spatial distribution of each assemblage, and Analysis of similarities (ANOSIM) to verify differences amongst dissimilarity distances. Additionally, we analyzed the main taxa associated with invasive macrophytes through indicator species analyses using IndVal index. We observed that the invasive macrophyte banks presented higher abundance of associated specimens, as well as lower dissimilarity of aquatic insect assemblages. Additionally, invasive macrophytes shifted the water pH and littoral depth of reservoir banks. The IndVal index indicated eight aquatic insects as indicator species. Labrundinia unicolor Silva, 2013, Ablabesmyia depaulai Neubern, 2013 and Diastatops Rambur, 1842 were indicator species on banks. We concluded that invasion of white ginger lily caused loss of shallow littoral habitat and altered the pH of the surrounding water probably by high decomposition rate and high production of plant biomass. We suggest the use of species of aquatic insects as indicator species to monitor white ginger lily impact in freshwater systems.(AU)

Forecasting the impact of an invasive macrophyte species in the littoral zone through aquatic insect species composition

Invasive macrophytes threaten freshwater ecosystem biodiversity. We analyzed the impact of the invasive white ginger lily (Hedychium coronarium J. Kõnig, Zingiberaceae) on aquatic insect assemblages living in the littoral zone of a tropical reservoir. We took aquatic insect samples in the littoral zone on four main vegetal profile banks: white ginger monotypic bank, forest partially invaded, native macrophyte monotypic bank and riparian forest. At each vegetal bank, we measured abiotic variables such as dissolved oxygen, pH, water temperature and depth. We analyzed the aquatic insects through abundance, richness and Simpson diversity. We used the non-Metric Multidimensional Scaling (nMDS) analysis to analyze the spatial distribution of each assemblage, and Analysis of similarities (ANOSIM) to verify differences amongst dissimilarity distances. Additionally, we analyzed the main taxa associated with invasive macrophytes through indicator species analyses using IndVal index. We observed that the invasive macrophyte banks presented higher abundance of associated specimens, as well as lower dissimilarity of aquatic insect assemblages. Additionally, invasive macrophytes shifted the water pH and littoral depth of reservoir banks. The IndVal index indicated eight aquatic insects as indicator species. Labrundinia unicolor Silva, 2013, Ablabesmyia depaulai Neubern, 2013 and Diastatops Rambur, 1842 were indicator species on banks. We concluded that invasion of white ginger lily caused loss of shallow littoral habitat and altered the pH of the surrounding water probably by high decomposition rate and high production of plant biomass. We suggest the use of species of aquatic insects as indicator species to monitor white ginger lily impact in freshwater systems.

Preliminary assessment of Hedychium coronarium essential oil on fibrinogenolytic and coagulant activity induced by Bothrops and Lachesis snake venoms

The search for new inhibitors of snake venom toxins is essential to complement or even replace traditional antivenom therapy, especially in relation to compounds that neutralize the local effects of envenomations. Besides their possible use as alternative to traditional antivenom therapy, some plant species possess bioactive secondary metabolites including essential oils, which can be extracted from weeds that are considered substantial problems for agriculture, such as Hedychium coronarium. The essential oils of leaves and rhizomes from H. coronarium were extracted by hydrodistillation, and their potential inhibitory effects on the coagulant and fibrinogenolytic activities induced by the venoms of Lachesis muta, Bothrops atrox and Bothrops moojeni were analyzed. Citrated human plasma was used to evaluate the clotting time whereas changes in fibrinogen molecules were visualized by electrophoresis in polyacrylamide gel. The experimental design used for testing coagulation inhibition was randomized in a 3 × 2 factorial arrangement (concentration × essential oils), with three replications. The essential oils were compared since they were extracted from different organs of the same botanical species, H. coronarium. The results suggest that the oils interact with venom proteases and plasma constituents, since all oils evaluated, when previously incubated with venoms, were able to inhibit the clotting effect, with less inhibition when oils and plasma were preincubated prior to the addition of venoms. Thus, after extensive characterization of their pharmacological and toxicological effects, the essential oils can be used as an alternative to complement serum therapy, especially considering that these plant metabolites generally do not require specific formulations and may be used topically immediately after extraction.(AU)

Preliminary assessment of Hedychium coronarium essential oil on fibrinogenolytic and coagulant activity induced by Bothrops and Lachesis snake venoms

The search for new inhibitors of snake venom toxins is essential to complement or even replace traditional antivenom therapy, especially in relation to compounds that neutralize the local effects of envenomations. Besides their possible use as alternative to traditional antivenom therapy, some plant species possess bioactive secondary metabolites including essential oils, which can be extracted from weeds that are considered substantial problems for agriculture, such as Hedychium coronarium. The essential oils of leaves and rhizomes from H. coronarium were extracted by hydrodistillation, and their potential inhibitory effects on the coagulant and fibrinogenolytic activities induced by the venoms of Lachesis muta, Bothrops atrox and Bothrops moojeni were analyzed. Citrated human plasma was used to evaluate the clotting time whereas changes in fibrinogen molecules were visualized by electrophoresis in polyacrylamide gel. The experimental design used for testing coagulation inhibition was randomized in a 3 × 2 factorial arrangement (concentration × essential oils), with three replications. The essential oils were compared since they were extracted from different organs of the same botanical species, H. coronarium. The results suggest that the oils interact with venom proteases and plasma constituents, since all oils evaluated, when previously incubated with venoms, were able to inhibit the clotting effect, with less inhibition when oils and plasma were preincubated prior to the addition of venoms. Thus, after extensive characterization of their pharmacological and toxicological effects, the essential oils can be used as an alternative to complement serum therapy, especially considering that these plant metabolites generally do not require specific formulations and may be used topically immediately after extraction.