Advances in farming technology and intensification of animal agriculture increase the cost-efficiency and production volume of meat. Thus, in developed nations, meat is relatively inexpensive and accessible. While beneficial for consumer satisfaction, intensive meat production inflicts negative externalities on public health, the environment and animal welfare. In response, groups within academia and industry are working to improve the sensory characteristics of plant-based meat and pursuing nascent approaches through cellular agriculture methodology (i.e., cell-based meat). Here we detail the benefits and challenges of plant-based and cell-based meat alternatives with regard to production efficiency, product characteristics and impact categories.

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Curcumin (CUR) is a natural food ingredient with known ability to target microbial cell membrane. In this study, the interactions of CUR with different types of model lipid bilayers (POPE, POPG, POPC, DOPC, and DPPE), mixtures of model lipid bilayers (POPE/POPG), and biological membrane mimics (Escherichia coli and yeast) were investigated by all-atom explicit solvent molecular dynamics (MD) simulation. CUR readily inserts into different types of model lipid bilayer systems in the liquid crystalline state, staying in the lipid tails region near the interface of lipid head and lipid tail. Parallel orientation to the membrane surface is found to be more probable than perpendicular for CUR, as indicated by the tilt angle distribution. This orientation preference is less significant as the fraction of POPE is increased in the system, likely due to the better water solvation of perpendicular orientation in the POPE bilayer. In E. coli and yeast bilayers, tilt angle distributions were similar to that for POPE/POPG mixed bilayer, with water hydration number around CUR for the former being higher. Insertion of CUR resulted in membrane thinning. The results from these simulations provide insights into the possible differences in membrane disrupting activity of CUR against different types of microorganisms.

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Antimicrobial peptides (AMPs) inactivate microorganisms by forming transmembrane pores in a cell membrane through adsorption and aggregation. Energetics of addition of an AMP to a transmembrane pore is important for evaluation of its formation and growth. Such information is essential for the characterization of pore forming ability of peptides in cell membranes. This study quantifies the potential of mean force through molecular dynamics (MD) simulation for the addition of melittin, a naturally occurring AMP, into a DOPC/DOPG mixed bilayer, a mimic of bacterial membrane, for different extents of insertion into either a bilayer or a pore consisting of three to six transmembrane peptides. The energy barrier for insertion of a melittin molecule into the bilayer was highest in the absence of transmembrane peptides and decreased for the number of transmembrane peptides from three to six, eventually approaching zero. The decrease in free energy for complete insertion of peptide was found to be higher for larger pore size. Water channel formation occurred only for insertion into pores consisting of three or more transmembrane peptides with the radius of water channel being larger for a larger number of transmembrane peptides. The structure of the pore was found to be paraboloid. The estimated free energy barrier for insertion of melittin into an ideal paraboloid pore accounting for different intermolecular interactions was consistent with MD simulation results. The results reported in this manuscript will be useful for the development of a model for nucleation of pores and a rational methodology for selection of synthetic antimicrobial peptides.