Degradation of phytic acid from tithonia (Tithonia diversifolia) leaves using Lactobacillus bulgaricus at different fermentation times

Pazla R, Yanti G, Jamarun N, Arief, Elihasridas, Sucitra LS. 2021. Degradation of phytic acid from tithonia (Tithonia diversifolia) leaves using Lactobacillus bulgaricus at different fermentation times. Biodiversitas 22: 4794-4798. The aim of this study is to reduce high level of phytic acid in tithonia (Tithonia diversifolia) leaves by fermentation technique using Lactobacillus bulgaricus. A completely randomized design consisting of four treatments (fermentation time) i.e. T2: 2 days, T3: 3 days, T4: 4 days and T5: 5 days and experiment was performed in four replicates. The parameters measured were pH, phytase enzyme activity, total bacterial colony, phytic acid content, and phytic acid degradation. The results showed that the fermentation time had a significant effect (P<0.05) on pH, phytase enzyme activity, total bacterial colony, phytic acid content, and phytic acid degradation. The conclusion of this study is that on fifth day (Treatment T5) fermented tithonia leaves produced the lowest levels of phytic acid (3.48 mg/ 100g) with the highest level of degradation (64.81%).

Oenococcus oeni Lifestyle Modulates Wine Volatilome and Malolactic Fermentation Outcome

In this study, nine Oenococcus oeni strains were tested for their ability to adhere to polystyrene using mMRS and wine as culture media. Moreover, planktonic and biofilm-detached cells were investigated for their influence on malic acid degradation kinetics and aroma compound production. Three strains were able to adhere on polystyrene plates in a strain-dependent way. In particular, MALOBACT-T1 and ISO359 strains mainly grew as planktonic cells, while the ISO360 strain was found prevalent in sessile state. The strain-dependent adhesion ability was confirmed by confocal laser scanning microscopy. Planktonic and biofilm detached cells showed a different metabolism. In fact, biofilm-detached cells had a better malic acid degradation kinetic and influenced the aroma composition of resulting wines, acting on the final concentration of esters, higher alcohols, and organic acids. Oenococcus oeni in biofilm lifestyle seems to be a suitable tool to improve malolactic fermentation outcome, and to contribute to wine aroma. The industrial-scale application of this strategy should be implemented to develop novel wine styles.

Comparative Transcriptome Analysis Revealed Genes Involved in Sexual and Polyploid Growth Dimorphisms in Loach (Misgurnus anguillicaudatus)

Sexual and polyploidy size dimorphisms are widespread phenomena in fish, but the molecular mechanisms remain unclear. Loach (Misgurnus anguillicaudatus) displays both sexual and polyploid growth dimorphism phenomena, and are therefore ideal models to study these two phenomena. In this study, RNA-seq was used for the first time to explore the differentially expressed genes (DEGs) between both sexes of diploid and tetraploid loaches in four tissues (brain, gonad, liver, and muscle). Results showed that 21,003, 17, and 1 DEGs were identified in gonad, liver, and muscle tissues, respectively, between females and males in both diploids and tetraploids. Regarding the ploidy levels, 4956, 1496, 2187, and 1726 DEGs were identified in the brain, gonad, liver, and muscle tissues, respectively, between tetraploids and diploids of the same sex. When both sexual and polyploid size dimorphisms were considered simultaneously in the four tissues, only 424 DEGs were found in the gonads, indicating that these gonadal DEGs may play an important regulatory role in regulating sexual and polyploid size dimorphisms. Regardless of the sex or ploidy comparison, the significant DEGs involved in glycolysis/gluconeogenesis and oxidative phosphorylation pathways were upregulated in faster-growing individuals, while steroid hormone biosynthesis-related genes and fatty acid degradation and elongation-related genes were downregulated. This suggests that fast-growing loaches (tetraploids, females) have higher energy metabolism levels and lower steroid hormone synthesis and fatty acid degradation abilities than slow-growing loaches (diploids, males). Our findings provide an archive for future systematic research on fish sexual and polyploid dimorphisms.