Food security and biodiversity conservation are threatened by the emergence and spread of pest and pathogens, and thus there is a current need to develop pest management strategies that are sustainable and friendly to the environment and human health. Here, we performed laboratory and field bioassays to evaluate the insecticidal effects of several concentrations of capsaicinoids and glucosinolates (separately and mixed) on an aphid pest (Aphis cytisorum). The capsaicinoids were extracted from the fruits of Capsicum chinense and glucosinolates from the tubers of native Andean crop Tropaeolum tuberosum. We found that both capsaicinoids and glucosinolates have a biocidal effect on A. cytisorum, acting within a fairly short time. Under laboratory conditions, the toxicity of the compounds increased in relation to their concentrations, causing a high percentage of mortality (83–99%) when the aphids were exposed to dilutions of 10% capsaicinoids, 75–100% glucosinolates, or a mixture of 10% capsaicinoids and 90% glucosinolates. The mortality of aphids sprayed in the field with 5% capsaicinoids, 50% glucosinolates, or with a mixture of 5% capsaicinoids and 45% glucosinolates reached 87–97%. Results obtained from laboratory and field experiments were consistent. Our results suggest the potential use of bioinsecticides based on capsaicinoids and/or glucosinolates as an effective alternative to synthetic pesticides.
Capsicum chinense Jacq. and C. baccatum var. pendulum fruits are widely used in the food and processed food industry, in Peru, but their seeds and placentas are discarded as residues. This study aimed to quantify the proportion of edible (pericarp) and non-edible (seeds, placenta and interlocular septa) parts of the fruits, in market condition (semi-dried fruits of C. chinense and fresh fruits of C. baccatum), as well as to quantify the capsaicinoids and their pungency, in extracts of each fruit part previously dried. The pericarp represents 63 % and 85 % of the fruit, respectively for C. chinense and C. baccatum. The placenta stands for ~10 % of the fruit in both species, whereas, for the seeds, the index is 23 % in C. chinense and 5 % in C. baccatum. The content of capsaicinoids and pungency vary among the fruit parts and the species. High contents of capsaicinoids and pungency are found in non-edible parts of the fruit, mainly in the placenta (79 % in C. chinense and 51 % in C. baccatum). Regardless of the fruit part and species, the capsaicin was the major component of capsaicinoids (4,399 ug g-1 and 1,582 ug g-1 of the dry weight in C. chinense and C. baccatum, respectively), while dihydrocapsaicin and nordihydrocapsaicin reached a lower content. C. chinense contains more capsaicinoids and, thus, a much higher level of pungency than the C. baccatum fruits.
Se realizó la producción de celulasas de Aspergillus niger ATCC 10864 mediante fermentación en biopelículas (FB). Los extractos de celulasas se usaron para hidrolizar la celulosa del fruto de Capsicun bacatum “ají escaveche”, para ello los frutos de ají fueron deshidratados y molidos a un tamaño de partícula menor a 0.425 mm. Luego se mezcló ají seco: celulasas y se hidrolizó en condiciones de agitación, tiempo y temperatura controlada. Se filtró el medio y se separó el sobrenadante de la torta de ají hidrolizado, este último se secó a 10% de humedad y se lixivió con una mezcla de hexano:acetona:etanol para extraer los carotenoides y capsaicinoides, los cuales fueron cuantificados por HPLC. El rendimiento de oleorresina extraída era cinco veces mayor comparado al método convencional; así mismo en los tratamientos T2 y T5, se logró mayor extracción de carotenoides y capsaicinoides totales, respectivamente, comparado a los otros tratamientos. La acción hidrolítica de las celulasas, sobre las estructuras moleculares de la celulosa del fruto ají escabeche, favorecieron mayor liberación de los carotenoides y capsaicinoides totales comparado a los métodos convencionales.