| Congresso Brasileiro de Microbiologia 2023 | Resumo: 356-1 | ||||
Resumo:Rosa chinensis Jacq. is among the flowers most consumed in natura and stands out for its delicate appearance, varied colors and citrus flavor. The use of fresh roses in salads and deserts have increased worldwide. Few is known about the microbial diversity of these food ingredients, which are raw consumed. In addition, due to fragility of fresh roses, emerging technologies have been suggested for microbial decontamination, but their effects remains unclear. This study aimed to evaluate the effect of glow discharge plasma (glow) on the microbiota of fresh roses through 16S rRNA amplicon sequencing analysis. Organic fresh roses were 20 min-treated in a PE-50 gas discharge plasma system (Plasma Etch) working at 50 kHz and 80 kV with an air flow rate of 20 mL/min. For high-throughput sequencing analyses, the DNA of roses glow treated and untreated was extracted using a PowerSoil Pro DNA isolation kit. Sequencing 16S rRNA (V3-V4) was performed on the Illumina PE 250 platform. The reads were mapped against the 16S rRNA reference database (Silva 138 Full Length, OTUs from the 341F/806R sequence region). The diversity indices Ace, Chao1, Fisher, Shannon and Simpson were higher in untreated roses (501.68, 499.99, 65.02, 4.68 and 0.86, respectively) than in glow treated roses (54.23, 54.00, 5.35, 1.36 and 0.40, respectively). Plasma glow reduced the abundance of Firmicutes (0.06 vs 27.35%), Actinobacteriota (0.03 vs 1.42%) and Desulfobacterota (0.00 vs 0.23%) phyla. At family level, roses treated with plasma glow showed lower abundance of Lactobacillaceae (0.00 vs 13.90%), and Bifidobacteriaceae (0.00 vs 1.35%). Roses treated with plasma glow, which had lower abundance of Lactobacillus (0.00 vs 14.23%) but interestingly had lower abundance of Rosenbergiella (80.74 vs 51.90%). Results report the bacterial diversity in edible fresh roses and the effects of a non-thermal technology proposed for their conservation. Findings show reduction in communities including spoilage bacteria. Palavras-chave: bacterial diversity, cold plasma, edible flowers, metabarcoding sequencing | |||||