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Diabetes is a multifactorial disorder that involves several molecular mechanisms and is still one of the key global health challenges with increasing prevalence and incidence. Gut microbiome dysbiosis could activate and recognize receptors that trigger the inflammation response and modulation of insulin sensitivity. In addition, the intricate role of gut microbiota dysbiosis in the onset and development of T2D (Type 2 diabetes mellitus) and associated microvascular complications was identified. These complications include diabetic nephropathy (DN) and diabetic retinopathy (DR), diabetic neuropathy, cerebrovascular disorders, and coronary heart disease. A recent interesting strategy to improve these complications is probiotics administration. The safety and health effects of probiotics against various diseases have been validated by various in vitro, in vivo and clinical studies. In this review, the related mechanisms between the gut microbiome, initiation, and progression of T2D and its common microvascular complications (DN and DR) have been discussed.

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We used gas chromatography-mass spectrometry (GC-MS) with an untargeted metabolomics approach to look at the metabolite profiles of traditional Iranian yogurts made from cow, goat, buffalo, and sheep milk. Results showed that different animal milks significantly influenced physicochemical properties and fatty acid (FA) composition, resulting in diverse metabolites. Over 80 % of all the fatty acids in the yogurt samples were saturated. The main fatty acids found were myristic acid (C14:0), palmitic acid (C16:0), and oleic acid + petroselenic acid (cis-9 C18:1 + cis-6 C18:1). In total, 36 metabolites, including esters, aldehydes, alcohols, and acids, were detected. Some important metabolites that changed yogurt profiles were 2-heptanone, methyl acetate, 2-propanone, butyl formate, and 4-methyl benzal. Associations between metabolite profiles and milk compositional traits were also observed, with statistical models showing a strong correlation between metabolite profiles and FA content. This study is the first to explore the impact of different animal sources and regions in Iran on the metabolome profiles of traditional yogurts. These results give us useful information about how metabolites differ between species and can be used to make new dairy products based on milk compositions and metabolites, which will help with future formulations of autochthonous starters.

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Systems biology is an interdisciplinary field that aims to understand complex biological processes at the system level. The data, driven by high-throughput omics technologies, can be used to study the underpinning mechanisms of metabolite production under different conditions to harness this knowledge for the construction of regulatory networks, protein networks, metabolic models, and engineering of strains with enhanced target metabolite production in microalgae. In the current study, we comprehensively reviewed the recent progress in the application of these technologies for the characterization of carotenoid biosynthesis pathways in microalgae. Moreover, harnessing integrated approaches such as network analysis, meta-analysis, and machine learning models for deciphering the complexity of carotenoid biosynthesis pathways were comprehensively discussed.

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The aim of this study was to identify and isolate lactic acid bacteria (LAB) from indigenous sourdough and dairy samples in Iran, and to assess their probiotic properties in vitro. A total of 560 potential LAB isolates were examined, and 87 demonstrated high survival rates in artificial gastrointestinal fluids without hemolytic activity. The selected isolates exhibited significant auto-aggregation (18.35 to 79.42%) and co-aggregation abilities (20.16 to 71.26%). Additionally, the isolates displayed varying degrees of cell surface hydrophobicity (12.32 to 76.24%). Results indicated that 19 LAB isolates had cholesterol assimilation rates exceeding 30%. Moreover, forty strains tested negative for all twelve assessed pathogenic genes and exhibited good adhesion to human intestinal epithelial cells (13.47 to 49.12%). Furthermore, 24 isolates formed strong biofilms, 29 formed moderate biofilms, and 23 formed weak biofilms. Except for isolates ABRIIFBI-8, ABRIIFBI-16, ABRIIFBI-23, ABRIIFBI-43, ABRIIFBI-56, and ABRIIFBI-62, most isolates were capable of producing exopolysaccharides. Consequently, LAB strains naturally occurring in sourdough and traditional dairy samples were suggested as potential probiotic candidates for incorporation into functional foods.

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Microalgae are photosynthetic organisms and a potential source of sustainable metabolite production. However, different stress conditions might affect the production of various metabolites. In this study, a meta-analysis of RNA-seq experiments in Dunaliella tertiolecta was evaluated to compare metabolite biosynthesis pathways in response to abiotic stress conditions such as high light, nitrogen deficiency and high salinity. Results showed downregulation of light reaction, photorespiration, tetrapyrrole and lipid-related pathways occurred under salt stress. Nitrogen deficiency mostly induced the microalgal responses of light reaction and photorespiration metabolism. Phosphoenol pyruvate carboxylase, phosphoglucose isomerase, bisphosphoglycerate mutase and glucose-6-phosphate-1-dehydrogenase (involved in central carbon metabolism) were commonly upregulated under salt, light and nitrogen stresses. Interestingly, the results indicated that the meta-genes (modules of genes strongly correlated) were located in a hub of stress-specific protein-protein interaction (PPI) network. Module enrichment of meta-genes PPI networks highlighted the cross-talk between photosynthesis, fatty acids, starch and sucrose metabolism under multiple stress conditions. Moreover, it was observed that the coordinated expression of the tetrapyrrole intermediated with meta-genes was involved in starch biosynthesis. Our results also showed that the pathways of vitamin B6 metabolism, methane metabolism, ribosome biogenesis and folate biosynthesis responded specifically to different stress factors. Since the results of this study revealed the main pathways underlying the abiotic stress, they might be applied in optimised metabolite production by the microalga Dunaliella in future studies. PRISMA check list was also included in the study.

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Two major aflatoxin-producing strains are Aspergillus flavus and Aspergillus niger. Probiotic bacteria have been identified as a potential means to fight aspergilli and reduce the availability of aflatoxin (AFs) as well as other food contaminants. In this study, the potential of ABRIIFBI-6 and ABRIIFBI-7 strains to inhibit the growth of aspergilli was investigated. Both strains survived in the simulated gastrointestinal conditions and inhibited the growth of Aspergillus significantly. Auto-aggregation ranged from 67.4 ± 1.9 for ABRIIFBI-6 to 75.8 ± 2.3% for ABRIIFBI-7, and hydrophobicity ranged from 57.3 ± 1.6 to 61.2 ± 1.4% for ABRIIFBI-6 and ranged from 51.2 ± 1.4 to 55.4 ± 1.8% for ABRIIFBI-7. The ranges of coaggregation with Staphylococcus aureus were 51.3 ± 1.7 and 52.4 ± 1.8% for ABRIIFBI-6 and ABRIIFBI-7, respectively, while coaggregation with Bacillus cereus was 57.9 ± 2.1 and 49.3 ± 1.9% for ABRIIFBI-6 and ABRIIFBI-7, respectively. Both strains indicated remarkable sensitivity to clinical antibiotics. According to the analysis of the identified potential probiotics, the findings of this study could significantly contribute to the understanding of the probiotic potential of LAB in dairy products in order to access their probiotic characterization for use as biocontrol of aflatoxin-producing species.

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This research aimed to isolate lactic acid bacteria from the bowel of saltwater fish to assess their potential probiotic properties. Nineteen isolates of LAB including Lactiplantibacillus plantarum, Lactiplantibacillus pentosus, Lactobacillus acidophilus, Levilactobacillus brevis, Pediococcus pentosaceus, and Pediococcus acidilactici were recognized using molecular tools. All the isolates survived in the simulated conditions of the GI tract. Auto-aggregation ranged from 01.3 ± 0.5 to 82.6 ± 1.4% and hydrophobicity with toluene ranged from 3.7 ± 1.6 to 69.4 ± 1.3%, while the range of hydrophobicity with xylene was from 02.2 ± 1.6 to 56.4 ± 2.1%. All the isolates of lactobacilli, pediococci, enterococci, and lactococci indicated variable sensitivity and resistance towards clinical antibiotics. Non-neutralized cell free supernatant of isolates F12 and F15 showed antimicrobial activity against all the 8 evaluated enteric pathogens. Cluster analysis of identified potential probiotic bacteria based on heat-map and PCA methods also highlighted the priority of isolates F3, F7, F12, and F15 as bio-control agents in fishery industry. The findings of this study may essentially contribute to the understanding of the probiotic potential of LAB in saltwater fish, in order to access their probiotic characterization for use as biocontrol in fishery.

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A novel Gram-negative, facultative anaerobic, rod-shaped, and non-motile bacterium with bio-degradation potential of polycyclic aromatic hydrocarbons (PAHs) and uranium bio-reduction, designated as RCRI7T, was isolated from Qurugöl Lake water near Tabriz city. Strain RCRI7T can grow in the absence of NaCl and tolerates up to 3% NaCl (optimum, 0-0.5%), at the temperature range of 4-45 °C (optimum, 30 °C) and a pH range of 6-9 (optimum, pH 7 ± 0.5). Results of phylogenetic analysis based on 16S rRNA gene sequence indicated that strain RCRI7T is affiliated with the genus Shewanella, most closely related to Shewanella xiamenensis S4T (99.1%) and Shewanella putrefaciens JCM 20190T (98.9%). The genomic DNA G+C content of strain RCRI7T is 41 mol%. The major fatty acids are C16:1ω9c, C18:1ω9c and iso-C17:1ω5c. The OrthoANI and ANIb values between RCRI7T and Shewanella xiamenensis S4T were 87.4% and 87.7%, and between RCRI7T and Shewanella putrefaciens JCM 20190T were 79.5% and 79.7%, respectively. Strain RCRI7T displayed dDDH values of 30.2% and 39.8% to Shewanella xiamenensis S4T and Shewanella putrefaciens JCM 20190T, respectively. The major polar lipids include phosphatidylglycerol (PG) and phosphatidylethanolamine (PE). The respiratory quinone is Q8. Based on the polyphasic evidence presented in this paper, strain RCRI7T is considered to represent a novel species, with bioremediation potential, in the genus Shewanella, for which the name Shewanella azerbaijanica sp. nov. is proposed. The type strain is RCRI7T (= JCM 17276T) (= KCTC 62476T).

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Clustered regularly interspaced short palindromic repeats (CRISPR) together with their CRISPR-associated (Cas) genes are widely distributed in prokaryotes that provide an adaptive defense mechanism against foreign invasive DNA. There is relatively little knowledge about the CRISPR-Cas diversity and evolution in Lactobacillus brevis strains. Therefore, in this study, a genome-mining approach was employed to investigate the diversity and occurrence of the CRISPR-Cas system in 83 L. brevis strains. Moreover, trans-activating CRISPR RNA (tracrRNA) and protospacer adjacent motif (PAM) as pivotal elements for the successful targeting and inference of phages by the subtype II CRISPR-Cas systems were surveyed. Finally, evolutionary paths of L. brevis strains under selective pressure from foreign invasive DNA such as plasmids and phages of studied strains were surveyed using acquisition and deletion events analysis of spacers. A total of 127 confirmed CRISPRs were identified, which were distributed in 69 strains. Among strains with confirmed CRISPRs, 35 strains only contained one CRISPR locus, 23 strains contained two CRISPR loci, and 12 strains contained three to six CRISPR loci. L. brevis strains frequently harbor more than one CRISPR system. Analysis of confirmed CRISPR arrays showed that 31 out of 127 confirmed CRISPRs included Cas genes which were categorized as one of the II-A, II-C, and I-E subtypes. Analysis of subtype II-A spacers reflected divergent evolution for 18 strains into 16 unique groups. Additional analysis of spacer sequences also confirmed the implication of characterizing CRISPR-Cas systems in targeting of phages and plasmids. The current study highlighted the potential of utilizing CRISPR spacer polymorphism in genotyping lactobacillus strains. Moreover, it provides deep insights into the occurrence, diversity, and functional impacts of the CRISPR-Cas system in L. brevis strains.

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Sourdoughs based on fermentation by lactobacilli have the potential to produce gluten-free maize-based bread with acceptable technological and rheological characteristics, nutritional quality, and more prolonged shelf life. Of the 17 treatments compared (with or without sourdough, and involving single and multiple LAB species), treatments 12C (Lactobacillus brevis, L sanfranciscensis + L. plantarum), and 8C (L. brevis + L. paralimentarius) showed the lowest rate of complex modulus, while treatments 11C (L. sanfranciscensis + L. brevis + L. paralimentarius) and 2C (L. brevis) led to the greatest reduction in baking loss. The crumb moisture content of all of the formulations decreased with storage. Breads produced with treatment 2C (L. brevis) had the highest crumb moisture content when freshly baked, while loaves produced with treatment 3C (L. paralimentarius) had the highest crumb moisture content after four days of storage. A sensory evaluation indicated that sourdough-based maize breads were superior to both control and chemically acidified breads. The optimal treatments were to use sourdough seeded with treatment 2C (L. brevis), with treatment 4C (L. plantarum), with treatment 8C (L. brevis + L. paralimentarius), or with treatment 11C (L. sanfranciscensis + L. brevis + L. paralimentarius).

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A novel moderately halophilic, Gram-staining negative and facultative aerobic bacterium, designated as TBZ9T, was isolated from water of Urmia Lake in Azerbaijan region of Iran. The cells were found to be rod-shaped and motile, growing in the form of creamy, convex and shiny colonies. The strain could grow in the presence of NaCl at concentrations 1-17% (w/v) (optimum, 3%), temperatures 10-40 °C (optimum, 30 °C) and pH 6.0-11.0 (optimum, pH 7.0) on marine agar. Strain TBZ9T 16S rRNA gene sequence was related to the genus Halomonas showing highest similarities to Halomonas arcis AJ282T (98.4%), Halomonas songnenensis NEAU-ST10-39T (98.0%) and Halomonas lutescens Q1UT (97.8%). In the phylogenetic trees, strain TBZ9T formed a distinct branch closely related to a subclade inside the Halomonas genus. Digital DNA-DNA hybridization (dDDH) and average nucleotide identity (ANI) values between strain TBZ9T and H. arcis AJ282T (20.0%, 74.0%) and H. songnenensis NEAU-ST10-39T (19.8%, 75.2%) indicated that TBZ9T represents a distinct species. Evaluation of fatty acid contents determined C10:0, C16:0, C12:0 3-OH, summed feature 3 (C16:1 ω7c and/or C16:1 ω6c) and summed feature 8 (C18:1 ω7c and/or C18:1 ω6c) as major cellular fatty acids. The major quinone of strain TBZ9T was Q-9. Polar lipid patterns consisted of phosphatidylglycerol (PG), phosphatidylethanolamine (PE), two unidentified phospholipids (PL) and four unidentified polar lipids (L). The average DNA G + C content of strain TBZ9T is 55.4 mol%. Results from phenotypic, chemotaxonomic and molecular analysis suggest that the strain TBZ9T represents a novel species within the genus Halomonas for which the name Halomonas azerica sp. nov. is proposed. The type strain is TBZ9T (= KACC 21783T = LMG 25775T).

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Despite responses to salinity stress in Dunaliella salina, a unicellular halotolerant green alga, being subject to extensive study, but the underlying molecular mechanism remains unknown. Here, Empirical Bayes method was applied to identify the common differentially expressed genes (DEGs) between hypersaline and normal conditions. Then, using weighted gene co-expression network analysis (WGCNA), which takes advantage of a graph theoretical approach, highly correlated genes were clustered as a module. Subsequently, connectivity patterns of the identified modules in two conditions were surveyed to define preserved and non-preserved modules by combining the Zsummary and medianRank measures. Finally, common and specific hub genes in non-preserved modules were determined using Eigengene-based module connectivity or module membership (kME) measures and validation was performed by using leave-one-out cross-validation (LOOCV). In this study, the power of beta = 12 (scale-free R2 = 0.8) was selected as the soft-thresholding to ensure a scale-free network, which led to the identification of 15 co-expression modules. Results also indicate that green, blue, brown, and yellow modules are non-preserved in salinity stress conditions. Examples of enriched Kyoto Encyclopedia of Genes and Genomes (KEGG) pathways in non-preserved modules are Sulfur metabolism, Oxidative phosphorylation, Porphyrin and chlorophyll metabolism, Vitamin B6 metabolism. Moreover, the systems biology approach was applied here, proposed some salinity specific hub genes, such as radical-induced cell death1 protein (RCD1), mitogen-activated protein kinase kinase kinase 13 (MAP3K13), long-chain acyl-CoA synthetase (ACSL), acetyl-CoA carboxylase, biotin carboxylase subunit (AccC), and fructose-bisphosphate aldolase (ALDO), for the development of metabolites accumulating strains in D. salina.

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This study describes the biochemical composition of three isolates, Dunaliella sp. ABRIINW-B1, -G2/1 and -I1 towards the biotechnological potential. Dunaliella sp. ABRIINW- G2/1 and -I1 had a remarkable protein content (∼40% dry weight). Dunaliella sp. ABRIINW-I1 contained a pigment fraction of 3.2% largely composed of chlorophyll a (1.9%) and carotenoid (1.1%). Dunaliella sp. ABRIINW-B1, -G2/1 and -I1 produced respectively 42, 36 and 47% lipid content. The occurrence of high lipid and low carbohydrate (4-7%) in the isolates demonstrated their cell tendency to store energy and carbon mainly in lipid form. The lipid profile of the isolates expressed adequate n3:n6 ratio and health indices. The biochemical analysis revealed that Dunaliella sp. ABRIINW-B1 and -G2/1 have potential applications in the food and freshwater aquafeed sector. While Dunaliella sp. ABRIINW-I1 owing to appropriate pigment, protein, and lipid level containing very-long-chain polyunsaturated fatty acids showed a great promise in nutritional, pharmaceutical and marine aquafeed industries.

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Heterotrophic cultures are the most effective approach to overcome low growth rate challenge in the most commercial microalgae. However, the mechanism through which heterotrophic condition regulates algae metabolism are not completely clear. Alternative Splicing (AS) is a common posttranscriptional process by which transcriptome and proteome plasticity increases at different environmental conditions. To identify and characterize of AS events in Auxenochlorella protothecoides microalga grown in autotrophic and heterotrophic, RNA-Seq data were analysed. We found that AS increased with the transition from autotrophic to heterotrophic condition. 705 and 660 differentially expressed (DEG) and spliced (DAS) genes were identified for A.protothecoides was transferred from autotrophic to heterotrophic condition, respectively. Moreover, there was slight coverage between DEG and DAS genes. Furthermore, functional analysis showed that the DAS genes are most frequently related to ion binding and stimulus response. The results also indicated that prevalence of Intron retention is associated with down-regulation of the genes involved in carotenoid biosynthesis. This study provides valuable insights into transcriptional and posttranscriptional plasticity of microalgae during growth mode change.

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Global warming, as a result of atmospheric CO2 increase, is regarded as an important universal concern. Microalgae are considered as appropriate microorganisms for CO2 assimilation. Here we aimed to investigate carbon biofixation ability of two indigenous isolates of Dunaliella spp. (ABRIINW-CH2 and ABRIINW-SH33) under elevated CO2 concentrations of 10, 20, and 30% (v/v) as well as their lipid content, productivity, and fatty acid profile under adjusted pH conditions. The maximum biomass production and CO2 biofixation rates were obtained under 10% CO2. High CO2 concentrations were favorable for the accumulation of lipids, lipid productivity, and polyunsaturated fatty acids formation. The highest lipid content and lipid productivity was obtained at 10% CO2. The highest fraction of the fatty acids (FA) profile was allocated to omega-3 FAs at 20% CO2. Accordingly, these isolates were able to tolerate extremely high CO2 concentrations and present even enhanced growth as well as formation of valuable products.

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Heterotrophic growth mode is among the most promising strategies put forth to overcome the low biomass and secondary metabolites productivity challenge. To shedding light on the underlying molecular mechanisms, transcriptome meta-analysis was integrated with weighted gene co-expression network analysis (WGCNA), connectivity analysis, functional enrichment, and hubs identification. Meta-analysis and Functional enrichment analysis demonstrated that most of the biological processes are up-regulated at heterotrophic growth condition, which leads to change of genetic architectures and phenotypic outcomes. WGNCA analysis of meta-genes also resulted four significant functional modules across logarithmic (LG), transition (TR), and production peak (PR) phases. The expression pattern and connectivity characteristics of the brown module as a non-preserved module vary across LG, TR, and PR phases. Functional analysis identified Carotenoid biosynthesis, Fatty acid metabolism and Methane metabolism as enriched pathways in the non-preserved module. Our integrated approach was applied here, identified some hubs, such as a serine hydroxymethyltransferase (SHMT1), which is the best candidate for development of metabolites accumulating strains in microalgae. Current study provided a new insight into underlying metabolite accumulation mechanisms and opens new avenue for the future applied studies in the microalgae field.

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In the course of screening halophilic bacteria in Urmia Lake in Iran, which is being threatened by dryness, a novel Gram-negative, moderately halophilic, heterotrophic and short rod-shaped bacteria was isolated and characterized. The bacterium was isolated from a water specimen and designated as TBZ3T. Colonies were found to be creamy yellow, with catalase- and oxidase-positive activities. The growth of strain TBZ3T was observed to be at 10-45 °C (optimum, 30 °C), at pH 6.0-9.0 (optimum, pH 7.0) and in the presence of 0.5-20 % (w/v) NaCl (optimum, 7.5 %). Strain TBZ3T contained C16 : 0, cyclo-C19 : 0 ω8c, summed feature 3 (comprising C16 : 1 ω7c and/or C16 : 1 ω6c) and summed feature 8 (comprising C18 : 1 ω7c and/or C18 : 1 ω6c) as major fatty acids and ubiquinone-9 as the only respiratory isoprenoid quinone. Diphosphatidylglycerol, phosphatidylglycerol, phosphatidylethanolamine, glycolipid, unidentified phospholipid and unidentified polar lipids were detected as the major polar lipids. Strain TBZ3T was found to be most closely related to Halomonas saccharevitans AJ275T , Halomonas denitrificans M29T and Halomonas sediminicola CPS11T with the 16S rRNA gene sequence similarities of 98.93, 98.15 and 97.60 % respectively and in phylogenetic analysis strain TBZ3T grouped with Halomonas saccharevitans AJ275T contained within a large cluster within the genus Halomonas. Based on phenotypic, chemotaxonomic and molecular properties, strain TBZ3T represents a novel species of the Halomonas genus, for which the name Halomonas urmiana sp. nov. is proposed. The type strain is TBZ3T (=DSM 22871T=LMG 25416T).

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A novel Gram-negative, aerobic, motile and rod-shaped bacterium with the potential to biodegrade polycyclic aromatic hydrocarbons, was isolated from Khazar (Caspian) Sea. Strain TBZ2T grows in the absence of NaCl and tolerates up to 8.5% NaCl. Growth occurred at pH 3.0-10.0 (optimum, pH 6.0-7.0) and 10-45 °C (optimum, 30 °C). The major fatty acids are C18:1ω7C, C16:1ω7C/ C15:0 iso 2-OH, C16:0, C12:0, C10:0 3-OH, C12:0 3-OH. The major polar lipids include diphosphatidylglycerol, phosphatidylglycerol, phosphatidylethanolamine, phosphatidylcholine and the predominant respiratory quinone is ubiquinone Q-9. The 16S rRNA gene sequence analysis showed that strain TBZ2T is a member of the genus Pseudomonas with the highest similarity to P. oleovorans subsp. oleovorans DSM 1045T (98.83%), P. mendocina NBRC 14162T (98.63%), P. oleovorans subsp. lubricantis RS1T (98.61%) and P. alcaliphila JCM 10630T (98.49%) based on EzBioCloud server. Phylogenetic analyses using housekeeping genes (16S rRNA, rpoD, gyrB and rpoB) and genome sequences demonstrated that the strain TBZ2T formed a distinct branch closely related to the type strains of P. mendocina and P. guguanensis. Digital DNA-DNA hybridisation and average nucleotide identity values between strain TBZ2T and its closest relatives, P. mendocina NBRC 14162T (25.3%, 81.5%) and P. guguanensis JCM 18146T (26.8%, 79.0%), rate well below the designed threshold for assigning prokaryotic strains to the same species. On the basis of phenotypic, chemotaxonomic, genomic and phylogenetic results, it is recommended that strain TBZ2T is a novel species of the genus Pseudomonas, for which the name Pseudomonas khazarica sp. nov., is proposed. The type strain is TBZ2T (= LMG 29674T = KCTC 52410T).

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Photosynthetic microalgae are potentially yielding sources of different high-value secondary metabolites. Salinity is a complex stress that influences various metabolite-related pathways in microalgae. To obtain a clear view of the underlying metabolic pathways and resolve contradictory information concerning the transcriptional regulation of Dunaliella species in salt stress conditions, RNA-seq meta-analysis along with systems levels analysis was conducted. A p-value combination technique with Fisher method was used for cross species meta-analysis on the transcriptomes of two Dunaliella salina and Dunaliella tertiolecta species. The potential functional impacts of core meta-genes were surveyed based on gene ontology and network analysis. In the current study, the integration of supervised machine-learning algorithms with RNA-seq meta-analysis was performed. The analysis shows that the lipid and nitrogen metabolism, structural proteins of photosynthesis apparatus, chaperone-mediated autophagy, and ROS-related genes are the keys and core elements of the Dunaliella salt stress response system. Cross-talk between Ca2+ signal transduction, lipid accumulation, and ROS signaling network in salt stress conditions are also proposed. Our novel approach opens new avenues for better understanding of microalgae stress response mechanisms and for selection of candidate gene targets for metabolite production in microalgae.

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The study investigated the effect of sourdough made from combinations of four Lactobacillus spp. on the physicochemical properties, consumer acceptability, and shelf life of bread made from pearl millet flour. Fermentation based on both single and multiple species reduced the pH of the dough and increased its titratable acidity and H2O2 content. The addition of sourdough increased the elasticity and reduced the stiffness of the pearl millet dough. Sourdough fermented with L. brevis had the greatest effect on loaf height, specific volume, porosity, and moisture content. During storage, the moisture content of the bread crumb decreased, but that of their crust increased. Sourdough-based loaves retained their moisture better than conventional loaves and the sourdough suppressed the development of mold for a longer period. An organoleptic assessment showed that the sourdough-based bread was more palatable than either conventional or chemically acidified ones. The tissue softness, chewiness, and flavor of the pearl millet bread decreased during storage. The use of sourdough based on either L. brevis, L. paralimentarius, or L. brevis + L. paralimentarius is recommended to produce high-quality pearl millet-based bread.