Coffee Science_v.18, 2023

URI permanente para esta coleçãohttps://thoth.dti.ufv.br/handle/123456789/13916

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    Lactic acid bacteria diversity and dynamics in Colombian coffee fermentation
    (Universidade Federal de Lavras, 2023-10-03) O'Byrne, Rosmery Cruz; Piraneque-Gambasica, Nelson; Aguirre-Forero, Sonia
    Lactic acid bacteria (LAB) are recognized in coffee fermentation as key microorganisms in forming flavor and aroma precursors associated with high-quality beverages. In Colombia, although coffees with differential sensory characteristics are produced from one region to another, only some studies have been performed on the microbiology of coffee fermentation, of which no research focused on LAB species has been reported. In this study, LAB diversity and dynamics associated with coffee fermentation in the Sierra Nevada de Santa Marta (SNSM) were determined through a temporal high-throughput sequencing approach, where the 16S rRNA gene was amplified and sequenced using the Illumina MiSeq platform. Finally, LAB species were identified using the BLASTN algorithms of the NCBI GenBank. The coffee fermentation process that lasted 36 hours was dominated by the genera Leuconostoc, followed by Lactobacillus and Weissella. Of the 118 OTUs corresponding to LAB, it was possible to identify 50 bacterial species, among which 28 are reported for the first time in coffee fermentation. Among the species widely reported in coffee fermentation are Leuconostoc mesenteroides, Leuconostoc pseudomesenteroides, Lactiplantibacillus plantarum (basonym: Lactobacillus plantarum), Levilactobacillus brevis (basonym: Lactobacillus brevis), and Lactococcus lactis. While the novel reports mainly correspond to species belonging to genera that were previously recognized as Lactobacillus, such as Lactiplantibacillus, Paucilactobacillus, Secundilactobacillus, Liquorilactobacillus, Lacticaseibacillus, Schleiferilactobacillus, Loigolactobacillus, Ligilactobacillus, Lentilactobacillus, Limosilactobacillus, and Latilactobacillus. These findings suggest that the indigenous LAB of the SNSM are responsible for generating metabolites that develop specific characteristics of coffee in the region, which is why coffee from the SNSM is protected by designation of origin. Isolates of the reported species should be considered for application as starter cultures.
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    Regeneration and development of Coffea arabica L. plants through indirect somatic embryogenesis
    (Universidade Federal de Lavras, 2023-03-10) Arimarsetiowati, Rina; Daryono, Budi Setiadi; Astuti, Yohana Theresia Maria; Prastowo, Erwin; Semiarti, Endang
    Micropropagation of AS2K clones Arabica coffee (Coffea arabica L.) was attempted through indirect somatic embryogenesis by using ten different parts of the leaf such as shoot, first leaf base, second leaf base, third leaf base, first leaf middle, second leaf middle, third leaf middle, first leaf tip, second leaf tip, and third leaf tip. The influence of the part of leaf explants, combination of plant growth regulator (PGRs) in the induction of embryogenic callus and regeneration of embryo somatic were studied. Furthermore, the various protocols to induce regeneration of somatic embryo into plantlet through different step of subculture and the use of various germination medium were demonstrated. The morphological characteristics and histological analysis of embryogenic callus and embryo development were observed. In this experiment, it was observed that the M5 medium supplemented with 1 mg/L 2,4-D, 1 mg/L BAP and 4 mg/L 2-ip was closely associated with third leaf tip explants for induction of embryogenic callus. The maximum number of globular, heart-shape, torpedo and cotyledones (18, 4, 12, 4, respectively) were achieved on ERM6 medium containing 2 mg/L BAP without activated charcoal on 90th day for regeneration of embryo somatic. The length of roots is the most influence paramater on plantlet regeneration, and the 17th protocol which used B medium, large embryos and twice phase of subculture from liquid medium to solid medium is the best protocol for plantlet regeneration. The protocol developed could be useful highly for large-scale micropropagation in these commercially important Arabica coffee clones