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Coffee is a critical agricultural commodity and is used to produce premium beverages enjoyed by people worldwide. The microbiome of coffee beans has proven to be an essential tool that improves the flavor profile of coffee by creating aromatic flavor compounds through natural fermentation. This study investigated the natural microbial consortium during the wet process fermentation of coffee onsite in Thailand in order to identify the correlation between microbial diversity and biochemical characteristics including flavor, aroma, and metabolic attributes. Our study found 64 genera of bacteria and 59 genera of yeast/fungi present during the fermentation process. Group of microbes, mainly yeast and lactic acid bacteria, that predominated in the process were significantly correlated with preferable flavor and aroma compounds, including linalyl formate, linalool, cis-isoeugenol, trans-geraniol, and (-)-isopulegol. Some of the detected metabolites were found to be active compounds which could play a role in health. [ABSTRACT FROM AUTHOR]

Background: This study explored the utilization of luffa sponge (LS) in enhancing acetification processes. LS is known for having high porosity and specific surface area, and can provide a novel means of supporting the growth of acetic acid bacteria (AAB) to improve biomass yield and acetification rate, and thereby promote more efficient and sustainable vinegar production. Moreover, the promising potential of LS and luffa sponge coated with κ-carrageenan (LSK) means they may represent effective alternatives for the co-production of industrially valuable bioproducts, for example bacterial cellulose (BC) and acetic acid. Methods: LS and LSK were employed as adsorbents for Acetobacter pasteurianus UMCC 2951 in a submerged semi-continuous acetification process. Experiments were conducted under reciprocal shaking at 1 Hz and a temperature of 32 °C. The performance of the two systems (LS-AAB and LSK-AAB respectively) was evaluated based on cell dry weight (CDW), acetification rate, and BC biofilm formation. Results: The use of LS significantly increased the biomass yield during acetification, achieving a CDW of 3.34 mg/L versus the 0.91 mg/L obtained with planktonic cells. Coating LS with κ-carrageenan further enhanced yield, with a CDW of 4.45 mg/L. Acetification rates were also higher in the LSK-AAB system, reaching 3.33 ± 0.05 g/L d as opposed to 2.45 ± 0.05 g/L d for LS-AAB and 1.13 ± 0.05 g/L d for planktonic cells. Additionally, BC biofilm formation during the second operational cycle was more pronounced in the LSK-AAB system (37.0 ± 3.0 mg/L, as opposed to 25.0 ± 2.0 mg/L in LS-AAB). Conclusions: This study demonstrates that LS significantly improves the efficiency of the acetification process, particularly when enhanced with κ-carrageenan. The increased biomass yield, accelerated acetification, and enhanced BC biofilm formation highlight the potential of the LS-AAB system, and especially the LSK-AAB variant, in sustainable and effective vinegar production. These systems offer a promising approach for small-scale, semi-continuous acetification processes that aligns with eco-friendly practices and caters to specialized market needs. Finally, this innovative method facilitates the dual production of acetic acid and bacterial cellulose, with potential applications in biotechnological fields. [ABSTRACT FROM AUTHOR]

The instability of the protein expression in Pichia pastoris strains has been an issue for various peptide productions. Some modifications to the traditional fermentation process could potentially solve the problem. Here, we consider a four-stage fermentation process to express the CAP2 (cell-penetrating antimicrobial peptide 2) candidate in P. pastoris KM71H, a slow methanol utilization strain. During the fermentation process, CAP2 productivity is limited (6.15 ± 0.21 mg/L·h) by the low overall methanol consumption (approximately 645 g), which is mainly the result of the slow methanol utilization of the P. pastoris KM71H. To overcome this limitation, we increased the cell concentration two-fold prior to the induction stage. A fed-batch process with exponential and dissolved oxygen tension (DOT) stat feeding strategies was deployed to control the glycerol feed, resulting in an increase in cell concentration and enhancement of the volumetric methanol consumption rate. The improved fermentation process increased the overall methanol consumption (approximately 1070 g) and the CAP2 productivity (13.59 ± 0.24 mg/L·h) by 1.66 and 2.21 times, respectively. In addition, the CAP3 (cell-penetrating antimicrobial peptide 3) candidate could also be produced using this improved fermentation process at a high yield of 3.96 ± 0.02 g/L without any further optimization. Note that there was no oxygen limitation during the improved fermentation process operating at high cell density. This could be due to the controlled substrate addition via the DOT stat system. [ABSTRACT FROM AUTHOR]

C-Phycocyanin, a blue-colored and water soluble protein, is a class of phycobiliproteins that are the major light-harvesting pigments of a photosynthetic system in cyanobacteria. C-phycocyanins are utilized in many industries, including as natural colorants in food and cosmetics and as antioxidant compounds. However, the uses of C-phycocyanins have been limited due to their vulnerability to high temperatures. Therefore, the objective of this study was to identify and analyze the C-phycocyanin gene isolated from Thermosynechococcus sp. TUBT-T01, living in a hot spring in Surat Thani province, in the hope that this C-phycocyanin exhibited thermostable properties and that their applications could be expanded over a wide range of industries. In the present study, the polymerase chain reaction of the gene encoding alpha subunits of C-phycocyanin (cpcA) was performed, using primers designed based upon the sequence alignments of cpcA from Thermosynechococcus sp. available in the GenBank database. The putative cpcA, with an approximate size of 500 base pairs, was detected on an agarose gel. The DNA sequencing analysis indicated that the cpcA was 489 base pairs in length, and its nucleotide sequence was 94 % identical to those of thermophilic Thermosynechococcus sp. NK55, T. elongatus BP-1, and Synechococcus vulcanus. The deduced amino acid sequence was very similar to those of Thermosynechococcus sp. NK55, T. elongatus BP-1, and S. vulcanus. The data derived from the homologous model revealed that the presence of Asp28, Lys32, and Ser72 in the alpha subunit of Cphycocyanin from Thermosynechococcus sp. TUBT-T01 could provide the high thermostability property of this protein. [ABSTRACT FROM AUTHOR]

An abstract of the paper "Human Prolactin (hPRL) and Growth Hormone (hGH) Distinct Behavior Under Bacteriophage Lambda PL Promoter Control," by Tais L. Oliveira, Susana R. Heller, and colleagues, is presented.

OBJECTIVE To investigate an alternative treatment for bovine mastitis by using Pm11 antimicrobial peptide. SAMPLE 5 bovine mastitis pathogens that were previously isolated from cows affected by either clinical or subclinical mastitis. PROCEDURES The current study introduces Pm11 antimicrobial peptide as an alternative treatment for bovine mastitis. The antibacterial activity of Pm11 was tested against Escherichia coli strain SCM1249, Klebsiella spp strain SCM1282, Staphylococcus aureus strain CM967, Streptococcus agalactiae strain SCM1084, and Streptococcus uberis strain SCM1310 using minimum bactericidal concentrations (MBCs) and time-kill kinetics. The pathogens' morphological changes were demonstrated using a scanning electron microscope (SEM). The cytotoxicity of Pm11 was assessed using the minimum hemolytic concentration assay. RESULTS MBCs ranged from 2.5 to 10 μM and IC50 ranged from 0.32 to 2.07 μM. Time-kill kinetics at MBC demonstrated that Pm11 reduced viable cell counts of S agalactiae strain SCM1084 and S uberis strain SCM1310 from 105 to 0 CFU/mL within 1 h. E coli strain SCM1249 and S aureus strain CM967 were reduced from 105 to 0 CFU/mL within 4 h. The average Pm11- induced hemolytic activity was < 10% for all Pm11 concentrations tested except at the maximum concentration tested (160 μM: 10.19 ± 2.29%). Based on SEM, Pm11 induced morphological and cellular changes in S aureus and E coli. CLINICAL RELEVANCE Pm11 antimicrobial peptide demonstrated in vitro antibacterial activity against the common bovine mastitis pathogens E coli, S aureus, S agalactiae, and S uberis, except Klebsiella spp, and should be further investigated in vivo. [ABSTRACT FROM AUTHOR]

The natural blue colorant C-phycocyanin (C-PC) has many potential applications but its poor heat stability limits its commercial use. This study compares the production and thermal stability of C-PC from two cyanobacteria: the thermophilic Thermosynechococcus sp. TUBT-T01 and the mesophilic Synechococcus cedrorum TISTR8589. Thermosynechococcus sp. produced nearly 1.9-fold more C-PC than S. cedrorum. Batch adsorption using a chromatographic cationic ion exchange resin (Streamline Direct HST1) was used to effectively purify the C-PC. The equilibrium adsorption capacity (Q eq ) of the resin for C-PC was the highest at pH 5. At this pH, the Q eq for the thermophilic C-PC was 5.5 ± 0.1 mg mL⁻¹ , whereas for the mesophilic C-PC it was 1.5 ± 0.2 mg mL⁻¹ . Purification increased the concentration of the thermophilic C-PC by 5.9-fold, and that of mesophilic C-PC by 4.2-fold. The purity ratios of the final products from the two cyanobacteria were similar at ∼2.2. At 60 °C and pH 7, the C-PC of Thermosynechococcus sp. had ∼12-times longer half-life than the mesophilic C-PC; however, the productivity of the thermophilic C-PC was comparatively low because of a low biomass productivity of Thermosynechococcus sp., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)