RESUMO
Biowaste treatment with black soldier fly larvae (BSFL, Hermetia illucens L.) can promote a more sustainable food system by reusing nutrients that would otherwise be wasted. However, many agri-food wastes and byproducts are typically high in lignocellulosic fibers (i.e., cellulose, hemicellulose, and lignin), making it resistant to efficient larval and/or microbial degradation. Ammonia pretreatment could be used to partially degrade lignocellulose, making the biowaste more easily degradable by the larvae and/or microorganisms. This study evaluated ammonia pretreatment for lignocellulose degradation and its effect on BSFL performance on four fibrous biowastes: brewers spent grain, cow manure, oat pulp, and grass clippings. First, the optimal ammonia dose (1 % or 5 % dry mass) and pretreatment time (three or seven days) were assessed by measuring fibers after treatment and further examined using Fourier transform infrared spectroscopy (FTIR) spectra and scanning electron microscopy (SEM) images. Second, BSFL rearing performance on ammonia-pretreated substrates was assessed with a 9-day feeding experiment. Three-day pretreatment with 5 % ammonia was chosen as it decreased the total fiber content by 8-23 % for all substrates except cow manure. Contrary to expectations, ammonia pretreatment with all substates decreased BSFL rearing performance metrics by more than half compared to the untreated control. Follow-up experiments suggested that ammonia pretreatment had a dose-dependent toxicity to BSFL. Interestingly, three-day fermentation of cow manure and oat pulp increased bioconversion rate by 25-31 %. This study shows that ammonia pretreatment is not suitable before BSFL rearing. Ammonia toxicity to BSFL and other pretreatments, such as fermentation, should be further studied.
Assuntos
Amônia , Dípteros , Animais , Bovinos , Feminino , Larva , Esterco , CarboidratosRESUMO
ABSTRACT: Gingival hyperpigmentation is produced by excessive melanin deposit, generating a dark gum coloring. Although it does not constitute a health issue, in some cases it usually represents an aesthetic problem that can affect psychologically, for which there are currently several treatment alternatives such as: surgery with scalpel, laser therapy, abrasion, cryosurgery, electrosurgery, among others. The aim of this literature review was to analyze the available information about gingival melanosis and the therapeutics that can be applied to improve the appearance of patients with this condition. Articles in English and Spanish, published during the period 2000-2020 in the PubMed, Medline, Scielo, Cochrane and Lilacs databases, were reviewed. It was concluded that the selection of the technique will depend on each particular case, however, the laser is the most relevant.
RESUMEN: La hiperpigmentación gingival se produce por el depósito excesivo de melanina, generando una coloración oscura de la encía. Aunque no constituye un inconveniente para la salud, en algunos casos suele representar un problema estético que puede afectar psicológicamente, por lo cual, en la actualidad existen diversas alternativas de tratamiento como: cirugía con bisturí, terapia láser, abrasión, criocirugía, electrocirugía, entre otros. El objetivo de esta revisión de la literatura fue analizar la información disponible acerca de la melanosis gingival y la terapéutica que puede ser aplicada para mejorar el aspecto de los pacientes con esta condición. Se revisaron artículos en inglés y español, publicados durante el período 2000-2020 en las bases de datos PubMed, Medline, Scielo, Cochrane y Lilacs. Se concluyó que la elección de la técnica dependerá de cada caso en particular, sin embargo, el láser es el más destacado.
Assuntos
Hiperpigmentação/classificação , Melanose/diagnóstico , Doenças da GengivaRESUMO
La hipermelanosis nevoide lineal o espiralada es un trastorno esporádico poco frecuente que es caracterizado por máculas hiperpigmentadas, reticuladas o lineales que siguen las líneas de Blaschko.En este artículo se presenta el caso de una infante de 1 año 6 meses con hipermelanosis nevoide. No hubo antecedentes familiares.Esta entidad no ha sido reportada en Ecuador. Se expone un caso clásico en relación a la literatura y sustentado en el examen histopatológico.
Linear or spiral nevus hypermelanosis is a rare sporadic disorder that is characterized by hyperpigmented, reticulated or linear macules that follow the Blaschko lines.This article presents the case of a 1 year old infant 6 months with nevoid hypermelanosis. There was no family history. This entity has not been reported in Ecuador. A classic case is presented in relation to the literature and supported by histopathological examination.
