The simulations and predictions obtained from mathematical models of bioprocesses conducted by microorganisms are not overvalued. Mechanistic models are bringing a better process understanding and the possibility of simulating unmeasurable variables. The Dynamic Energy Budget (DEB) model is an energy balance that can be formulated for any living organism and can be classified as a structured model. In this study, the DEB model was used to describe E. coli growth in a batch reactor in carbon and nitrogen substrate limitation conditions. The DEB model provides a possibility to follow the changes in the microbes\' cells including their elemental composition and content of some important cell ingredients in different growth phases in substrate limitation conditions which makes it more informative compared to Monod\'s model. The model can be used as an optimal choice between Monod-like models and flux-based approaches. KEY POINTS: • The DEB model can be used to catch changes in elemental composition of E. coli • Bacteria batch culture growth phases can be explained by the DEB model • The DEB model is more informative compared to Monod\'s based models.

Cordyceps militaris, a medicinal fungus rich in cordycepin, shows promise in treating diseases such as cancer, respiratory issues, and COVID-19. This study examines the impact of different Taiwanese rice varieties on its solid-state fermentation, focusing on optimizing cordycepin production. The results indicated that the cordycepin yield was indeed affected by the type of rice used. In terms of the fruiting bodies, germ rice resulted in the highest yield (13.1 ± 0.36 mg/g), followed by brown rice (11.9 ± 0.26 mg/g). In the rice culture medium (RCM), brown rice led to the highest yield (4.77 ± 0.06 mg/g). Using gas chromatography-mass spectrometry and untargeted metabolomics, the study identifies four key volatile components linked to cordycepin, providing insights into developing functional rice porridge products. These findings are significant for advancing cordycepin mass production and offering dietary options for older individuals.

This study investigated the potential of endophytic fungi to produce paclitaxel (Taxol®), a potent anticancer compound widely employed in chemotherapy. This research aimed to identify, confirm, and characterize endophytic fungi capable of paclitaxel (PTX) production and assess their paclitaxel yield. Additionally, it aimed to investigate factors influencing paclitaxel production. A total of 100 endophytic fungal isolates were collected and identified from the roots of Artemisia judaica. Aspergillus fumigatiaffinis exhibited the highest PTX production (26.373 μg L-1) among the isolated endophytic fungi. The strain was identified as A. fumigatiaffinis (Accession No. PP235788.1). Molecular identification confirmed its novelty, representing the first report of PTX production by A. fumigatiaffinis, an endophyte of Artemisia judaica. Optimization through full factorial design of experiments (DOE) and response surface methodology (RSM) significantly enhanced PTX production to 110.23 μg L-1 from 1 g of dry weight of the fungal culture under optimal conditions of pH 8.0, 150 μg L-1 becozyme supplementation, and 18 days of fermentation in potato dextrose broth. The presence of paclitaxel was confirmed using thin layer chromatography, high performance liquid chromatography, and gas chromatography-mass spectrometry. These findings maximize the role of endophytic fungus to produce a secondary metabolite that might be able to replace the chemically produced PTX and gives an opportunity to provide a sustainable source of PTX eco-friendly at high concentrations. KEY POINTS: • Endophytic fungi, like A. fumigatiaffinis, show promise for eco-friendly paclitaxel production • Optimization strategies boost paclitaxel yield significantly, reaching 110.23 μg L -1 • Molecular identification confirms novelty, offering a sustainable PTX source.

UNASSIGNED: Amphiregulin (AR) is a growth factor that resembles the epidermal growth factor (EGF) and serves various functions in different cells. However, no systematic studies or reports on the role of AR in human oocytes have currently been performed or reported. This study aimed to explore the role of AR in human immature oocytes during in vitro maturation (IVM) and in vitro fertilization (IVF) in achieving better embryonic development and to provide a basis for the development of a pre-insemination culture medium specific for cumulus oocyte complexes (COCs).
UNASSIGNED: First, we examined the concentration of AR in the follicular fluid (FF) of patients who underwent routine IVF and explored the correlation between AR levels and oocyte maturation and subsequent embryonic development. Second, AR was added to the IVM medium to culture immature oocytes and investigate whether AR could improve the effects of IVM. Finally, we pioneered the use of a fertilization medium supplemented with AR for the pre-insemination culture of COCs to explore whether the involvement of AR can promote the maturation and fertilization of IVF oocytes, as well as subsequent embryonic development.
UNASSIGNED: A total of 609 FF samples were examined, and a positive correlation between AR levels and blastocyst formation was observed. In our IVM study, the development potential and IVM rate of immature oocytes, as well as the fertilization rate of IVM oocytes in the AR-added groups, were ameliorated significantly compared to the control group (All P < 0.05). Only the IVM-50 group had a significantly higher blastocyst formation rate than the control group (P < 0.05). In the final IVF study, the maturation, fertilization, high-quality embryo, blastocyst formation, and high-quality blastocyst rates of the AR-added group were significantly higher than those of the control group (All P < 0.05).
UNASSIGNED: AR levels in the FF positively correlated with blastocyst formation, and AR involvement in pre-insemination cultures of COCs can effectively improve laboratory outcomes in IVF. Furthermore, AR can directly promote the in vitro maturation and developmental potential of human immature oocytes at an optimal concentration of 50 ng/ml.

BACKGROUND: Stem cell-derived therapies hold the potential for treatment of regenerative clinical indications. Static culture has a limited ability to scale up thus restricting its use. Suspension culturing can be used to produce target cells in large quantities, but also presents challenges related to stress and aggregation stability.
METHODS: Utilizing a design of experiments (DoE) approach in vertical wheel bioreactors, we evaluated media additives that have versatile properties. The additives evaluated are Heparin sodium salt (HS), polyethylene glycol (PEG), poly (vinyl alcohol) (PVA), Pluronic F68 and dextran sulfate (DS). Multiple response variables were chosen to assess cell growth, pluripotency maintenance and aggregate stability in response to the additive inputs, and mathematical models were generated and tuned for maximal predictive power.
RESULTS: Expansion of iPSCs using 100 ml vertical wheel bioreactor assay for 4 days on 19 different media combinations resulted in models that can optimize pluripotency, stability, and expansion. The expansion optimization resulted in the combination of PA, PVA and PEG with E8. This mixture resulted in an expansion doubling time that was 40% shorter than that of E8 alone. Pluripotency optimizer highlighted the importance of adding 1% PEG to the E8 medium. Aggregate stability optimization that minimizes aggregate fusion in 3D culture indicated that the interaction of both Heparin and PEG can limit aggregation as well as increase the maintenance capacity and expansion of hiPSCs, suggesting that controlling fusion is a critical parameter for expansion and maintenance. Validation of optimized solution on two cell lines in bioreactors with decreased speed of 40 RPM, showed consistency and prolonged control over aggregates that have high frequency of pluripotency markers of OCT4 and SOX2 (> 90%). A doubling time of around 1-1.4 days was maintained after passaging as clumps in the optimized medium. Controlling aggregate fusion allowed for a decrease in bioreactor speed and therefore shear stress exerted on the cells in a large-scale expansion.
CONCLUSIONS: This study resulted in a control of aggregate size within suspension cultures, while informing about concomitant state control of the iPSC state. Wider application of this approach can address media optimization complexity and bioreactor scale-up challenges.

This chapter outlines the workflow using the ExpiSf™ Expression System designed for high-density infection of suspension ExpiSf9™ cells. The system utilizes a chemically defined, serum-free, protein-free, and animal origin free medium, making it suitable for recombinant protein expression experiments. The ExpiSf™ chemically defined medium allows efficient transfection and baculovirus production directly within the same culture medium. The ExpiSf™ Expression System Starter Kit provides all necessary components, including cells, culture medium, and reagents needed to infect one (1) liter of cell culture. The system\'s versatility and animal origin free nature make it a valuable tool for various protein expression studies and biotechnological applications.

Myxococcus xanthus synthesizes polyphosphates (polyPs) with polyphosphate kinase 1 (Ppk1) and degrades short- and long-chain polyPs with the exopolyphosphatases, Ppx1 and Ppx2, respectively. M. xanthus polyP:AMP phosphotransferase (Pap) generates ADP from AMP and polyPs. Pap expression is induced by an elevation in intracellular polyP concentration. M. xanthus synthesized polyPs during the stationary phase; the ppk1 mutant died earlier than the wild-type strain after the stationary phase. In addition, M. xanthus cells cultured in phosphate-starved medium, H2O2-supplemented medium, or amino acid-deficient medium increased the intracellular polyP levels by six- to ninefold after 6 h of incubation. However, the growth of ppk1 and ppx2 mutants in phosphate-starved medium and H2O2-supplemented medium was not significantly different from that of wild-type strain, nor was there a significant difference in fruiting body formation and sporulation in starvation condition. During development, no difference was observed in the adenylate energy charge (AEC) values in the wild-type, ppk1 mutant, and pap mutant strains until the second day of development. However, after day 3, the ppk1 and pap mutants had a lower ADP ratio and a higher AMP ratio compared to wild-type strain, and as a result, the AEC values of these mutants were lower than those of the wild-type strain. Spores of ppk1 and pap mutants in the nutrient medium germinated later than those of the wild-type strain. These results suggested that polyPs produced during development may play an important role in cellular energy homeostasis of the spores by being used to convert AMP to ADP via Pap.

Introduction. The absence of a gold-standard methodology for the microbiological diagnosis of urinary tract infections (UTI) has led to insufficient standardization of criteria for the interpretation of results and processing methods, particularly incubation time and culture media.Hypothesis. 48-hour incubation time period and use of blood agar enhances the sensitivity of microorganisms isolated significantly.Aim. To determine the sensitivity of blood agar and Brilliance UTI chromogenic agar, incubating for different periods (24-48 hours), for the detection of positive urine cultures.Methodoloy. Comparisons were made between all possible combinations of media and incubation times. As the gold-standard reference, we used the routine methodology of our laboratory, which involves prior screening with available clinical data, flow cytometry, sediment analysis and/or Gram staining. Screened samples were then cultured on blood agar and chromogenic agar and incubated for 48 hours. Also, based on the results of Gram staining, additional media were added in selected cases.Results. The most significant difference was found between chromogenic agar incubated for 24 hours and blood agar incubated for 48 hours, with the latter method allowing the recovery of 10.14 % more microorganisms (P < 0.0001). Furthermore, the value of performing Gram staining to guide processing was demonstrated, as it avoided the loss of at least 5.14 % of isolates.Conclusions. At least in urological and nephrological patients it is essential to include enriched culture media (blood agar) or to extend the incubation times due to the improvement of the diagnostic sensitivity of urine cultures. Gram staining also can help detect the presence of fastidious microorganisms or mixed infections, indicating whether rich and/or selective media should be included to enhance the diagnostic sensitivity of cultures. If this methodology is not followed, it should be noted that besides fastidious species, fastidious strains of Escherichia coli, Proteus mirabilis, Pseudomonas aerugniosa and Stenotrophomonas maltophilia will also be missed.

Prior research has established the anti-apoptotic effects in insect cell cultures of Bombyx mori (B. mori) hemolymph, as well as the heightened production yields of recombinant proteins facilitated by baculovirus vectors in insect cells cultivated in media supplemented with this hemolymph. In this study, we investigated the hemolymph of another Lepidoptera species, Trichoplusia ni (T. ni), and observed similar beneficial effects in insect cells cultivated in media supplemented with this natural substance. We observed enhancements in both production yield (approximately 1.5 times higher) and late-stage cell viabilities post-infection (30-40% higher). Storage-protein 2 from B. mori (SP2Bm) has previously been identified as one of the abundant hemolymph proteins potentially responsible for the beneficial effects observed after the use of B. mori hemolymph-supplemented cell culture media. By employing a dual baculovirus vector that co-expresses the SP2Bm protein alongside the GFP protein, we achieved a threefold increase in reporter protein production compared to a baculovirus vector expressing GFP alone. This study underscores the potential of hemolymph proteins sourced from various Lepidoptera species as biotechnological tools to augment baculovirus vector productivities, whether utilized as natural supplements in cell culture media or as hemolymph-derived recombinant proteins co-expressed by baculovirus vectors.

The strain Gluconobacter oxydans LMG 1385 was used for the bioconversion of crude glycerol to dihydroxyacetone. The suitability of fed-batch cultures for the production of dihydroxyacetone was determined, and the influence of the pH of the culture medium and the initial concentration of glycerol on maximizing the concentration of dihydroxyacetone and on the yield and speed of obtaining dihydroxyacetone by bioconversion was examined. The feeding strategy of the substrate (crude glycerol) during the process was based on measuring the dissolved oxygen tension of the culture medium. The highest concentration of dihydroxyacetone PK = 175.8 g·L-1 and the highest yield YP/Sw = 94.3% were obtained when the initial concentration of crude glycerol was S0 = 70.0 g·L-1 and the pH of the substrate was maintained during the process at level 5.0.