Humans lack the enzyme cellulase, necessary for breaking down cellulose, a complex carbohydrate found in plant cell walls. However, certain gut bacteria partially digest cellulose, converting it into short-chain fatty acids that our body can absorb. This process does not release usable energy equivalent to that from other carbohydrates but aids digestive health by promoting a healthy microbiome and regular bowel movements. Technologically, cellulose can be chemically or enzymatically treated to produce derivatives like cellulose ethanol or to extract glucose for fermentation in industrial processes, providing a potential indirect method for "digesting" cellulose for human benefit. Direct consumption of cellulose for nutritional value remains largely unfeasible due to human digestive limitations.

When traveling with ink, whether for fountain pens, tattoos, or other purposes, it's crucial to prepare carefully to avoid spills and damage. For air travel, adhere to TSA guidelines: inks must fit into a quart-sized bag and be under 3.4 ounces (100ml) unless they're in checked luggage. Secure ink bottles tightly and wrap them in a plastic bag or bubble wrap for extra protection. For fountain pen users, empty your pen or use a converter with silicone grease to prevent leaks. Consider carrying pre-filled cartridges as they're less prone to leaking. Always inform security about your ink to avoid confusion. Lastly, keep your inks in a cool, dry place during transit to maintain their integrity.

Viking Ink, a brand known for its range of tattoo inks, is generally considered safe by professional tattoo artists. The company adheres to strict manufacturing standards, ensuring that their products are free from harmful contaminants. Viking Ink uses an FDA-compliant ingredient list and follows Good Manufacturing Practices (GMP), which includes sterilizing all inks through a gamma irradiation process. This not only eliminates bacteria but also ensures the consistency and quality of the ink. However, like any tattoo ink, individual reactions can occur, so it's important to conduct a patch test before using Viking Ink on clients. Furthermore, it's crucial that the ink is handled and stored properly to maintain its integrity and safety. Overall, Viking Ink is a reliable choice for tattoo artists looking for high-quality, safe inks.