It is important to understand how physiological state of the host influence propagation of bacteriophages (phages), due to the potential higher phage production needs in the future. In our study, we tried to elucidate the effect of bacterial growth rate on adsorption constant (δ), latent period (L), burst size (b), and bacteriophage population growth rate (λ). As a model system, a well‐studied phage T4 and Escherichia coli K‐12 as a host was used. Bacteria were grown in a continuous culture operating at dilution rates in the range between 0.06 and 0.98 hr−1. It was found that the burst size increases linearly from 8 PFU·cell−1 to 89 PFU·cell−1 with increase in bacteria growth rate. On the other hand, adsorption constant and latent period were both decreasing from 2.6∙10‐9 ml·min−1 and 80 min to reach limiting values of 0.5 × 10‐9 ml·min−1 and 27 min at higher growth rates, respectively. Both trends were mathematically described with Michaelis–Menten based type of equation and reasons for such form are discussed. By applying selected equations, a mathematical equation for prediction of bacteriophage population growth rate as a function of dilution rate was derived, reaching values around 8 hr−1 at highest dilution rate. Interestingly, almost identical description can be obtained using much simpler Monod type equation and possible reasons for this finding are discussed.

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The marine alkaloids clathrodin, oroidin, and hymenidin, which were isolated from Agelas sponges, possess diverse biological activities. Herein, we describe the design of a library of their analogues and the evaluation of their apoptosis-inducing activities against the human hepatocellular carcinoma HepG2 and acute monocytic leukaemia THP-1 cell lines. The screening of the complete library of 96 compounds using the HepG2 cell line allowed us to determine key structural elements and physicochemical properties that are responsible for the apoptosis-inducing activity. The indole-based compounds 24c, 28c, 29c, and 34cwere found to be the most potent inducers of apoptosis in HepG2 and THP-1 cell lines with EC 50 values in the low micromolar range. Cell cycle analysis assays confirmed that compounds 24c, 28c, 29c, and 34c induce the apoptosis of THP-1 cells at 25 mM, which highlights these oroidin analogues as interesting candidates for further evaluation of their anticancer activity.