RESUMO
Introduction: The aim of the research was to demonstrate the efficiency of microorganisms and the effectiveness of biodegradation techniques on Low-density polyethylene (LDPE) plastics. The research question was: What is the efficiency of LDPE-degrading microorganisms and the effectiveness of biodegradation techniques? Methods: The systematic review was based on the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) statement. Articles were obtained from Scopus, Web of Science (WOS), Embase, and Google Scholar. The DeCS/Mesh search terms were: Low-density polyethylene, efficiency, biodegradation, microbial consortia, fungi, bacteria. Inclusion criteria were: scientific articles that included bacteria, fungi, and microbial consortia reported as LDPE degraders that report the percentage of weight loss; articles published from January 2010 to October 2022, and publications in Spanish and English with open access. Exclusion criteria were: studies that do not report gravimetry, the biodegradation time of LDPE, and the genus or species of the polyethylene-degrading microorganism. Results: Out of 483 studies found, 50 were included in this Systematic Review (SR). The most frequent study techniques were scanning electron microscopy (SEM), gravimetry, and fourier transform infrared spectroscopy (FTIR), and in the case of microorganisms, the most studied belonged to the genus Pseudomonas, Bacillus, and Aspergillus. Regarding the isolation place, the most frequent mentioned in the reviewed articles were landfill soil and sanitary landfill soil. The efficiency of LDPE-degrading microorganisms was higher in bacteria such as Enterobacter spp., Pantoea spp., Pseudomonas spp., Escherichia coli, and Bacillus spp., which obtained a range of DE of 9.00-70.00%, 24.00-64%, 1.15 - 61.00%, 45.00%, and 1.5-40% with DT of 4-150, 120, 4-150, 30, and 30-120 days, respectively; in the case of fungi, the main microorganisms are Neopestalotiopsis phangngaensis, Colletotrichum fructicola, and Thyrostroma jaczewskii with efficiencies of 54.34, 48.78, and 46.34%, in 90 days, respectively; and the most efficient microbial consortia were from Enterobacter spp. and Pantoea sp. with 38.00 - 81.00%, in 120 days; and, Pseudomonas protegens, Stenotrophomonas sp., B. vallismortis and Paenibacillus sp. with 55. 00 - 75.00% in 120 days. Conclusions: The most efficient microorganisms in LDPE degradation are Enterobacter spp., Pantoea spp., Pseudomonas spp., Escherichia coli, and Bacillus spp.; in fungi Neopestalotiopsis phangngaensis, Colletotrichum fructicola, and Thyrostroma jaczewskii; and in microbial consortia, those formed by Enterobacter spp. and Pantoea sp., and that of P. protegens, Stenotrophomonas sp., B. vallismortis and Paenibacillus sp.; and the most effective techniques used in LDPE biodegradation are SEM, gravimetry, and FTIR.
RESUMO
Introduction: Understanding the use of medicinal plants as herbal medicines is considered essential for the survival and continuity of humanity. Since ancient times, the origin and development of natural and traditional medicine have been intrinsically linked to humanity struggle for survival. Nowadays, ethnobotanical studies are employed as a tool for the preservation and conservation not only of taxonomic biodiversity but also of cultural biodiversity. Methodology: A descriptive research with a quantitative, non-experimental cross-sectional design was carried out. The study was conducted in six Quechua-speaking communities in the district of Incahuasi (3,000 meters above sea level), selected for convenience considering factors such as altitude, accessibility, and proximity to the city. A questionnaire was administered to 32 residents from the communities, who shared their knowledge about medicinal plants, providing relevant information about them. The gender of the participants was considered because men and women use traditional medicine and the knowledge of them is transmitted from parents to children. Results: During the study, a total of 46 medicinal species were recorded, belonging to 42 genera and 22 botanical families. The most representative medicinal families used by the informants of the communities were Asteraceae (30.4%) and Lamiaceae (15.2%). It is also worth mentioning the genera Salvia and Baccharis, with three and two species respectively, which are commonly used to treat various ailments and diseases. Conclusions: Ethnobotanical information was collected on the medicinal plants used by the community members of the selected communities in Incahuasi, and the corresponding data were recorded. A total of 46 plants were collected, with the majority belonging to the Asteraceae and Lamiaceae families.