Biophysica

Antimicrobial resistance represents not only a biological challenge but also a physicochemical limitation associated with antibiotic transport, membrane interaction, and local availability. In this preliminary study, a liposome-encapsulated doxycycline delivery system was developed using egg yolk-derived phospholipids, and its biophysical properties and release behavior were investigated. Phospholipids were isolated from egg yolk and used to prepare doxycycline-loaded liposomes via a thin-film hydration method combined with freeze–thaw processing. Liposome morphology was characterized by atomic force microscopy (AFM), while encapsulation efficiency was quantified by reversed-phase high-performance liquid chromatography (RP-HPLC). In vitro release kinetics were evaluated using a dialysis diffusion method, and antibacterial activity was assessed as a functional indicator of drug availability using minimum inhibitory concentration (MIC) assays against Staphylococcus aureus and methicillin-resistant S. aureus (MRSA). The prepared liposomes exhibited morphology with diameters of approximately 153 nm (PDI = 0.223). The encapsulation efficiency of doxycycline hyclate was 8.41%, and complete drug release was achieved within 48 h. Liposome-encapsulated doxycycline demonstrated a two-fold reduction in MIC values compared with free doxycycline. These findings offer preliminary insight to support further optimization and expanded investigation of liposome-encapsulated antibiotic delivery systems.

Cancer is the second leading cause of death worldwide, requiring more effective treatments. By-products from the white shrimp (Penaeus vannamei) are a promising source of bioactive compounds. Compounds with antiproliferative activity were isolated and identified in exoskeleton and cephalothorax extracts. The hexane extract of the exoskeleton reduced the viability of Human Prostate Carcinoma cell line (22Rv1) to 40.6% without toxicity in Adult Retinal Pigment Epithelium-19 (ARPE-19). Among the 19 fractions obtained, H3 reduced cell viability to 20.78%. Spectroscopic analysis identified bis(2-ethylhexyl) terephthalate, neoxanthin, and violaxanthin. Fluorescence microscopy showed morphological alterations. These findings demonstrate in vitro antiproliferative activity of compounds derived from shrimp by-products and support further studies to elucidate their mechanisms of action and evaluate their potential relevance in cancer prevention or therapeutic research.

Traditional drug design methods based on trial and error are costly and inefficient. The computational approach ToSS-MoDE (Topological Substructural Molecular Design) offers an alternative by linking molecular descriptors to biological activity. To develop a QSAR model to predict the anti-inflammatory activity of synthetic and natural compounds using weighted spectral moments. Spectral moments (µ_k) were calculated from the adjacency matrix between bonds for 410 compounds (180 active and 230 inactive). MODESLAB software (MICROSOFT OFFICE 365) was used to generate descriptors, and Linear Discriminant Analysis (LDA) was applied to classify activity. The model was validated with an external series of 62 compounds. Results. The model showed an overall classification of 91.59% in the training series and 90.2% in validation. The spectral moments µ₀, µ₃, µ₄, and µ₅ were the most significant. Diosgenin, a natural metabolite, showed potential anti-inflammatory activity (classification probability: 81%). The model showed strong training performance (91.7% accuracy) and promising external performance for confidently classified compounds. All datasets, descriptor-generation settings, coefficients, and posterior probabilities are fully described in the main text to ensure full reproducibility.