Kolonia is exactly what it sounds like - Colony.
As for Laden, you are in trouble. There is no such place in the long list of villages at www.odessa3.org/collections/refs/link/villhelp.txt
First I double checked the passenger list (I assume you are referring to the Komm family) and the name is clearly written. There are also no additional clues regarding a region or parish.
There is a slim possibility that the place name should be Ladonowka which is on the list. Sometimes Germans dropped the "owka" from a place name and used only the root word but I have no way of knowing if that is the case here. This is a pure guess.
Best suggestion might be to research their relatives mentioned in the passenger list - the Nikolaus Feist family at Eureka. If you can find their place of origin, it might lead you to Kolonia Laden.
ShtetlSeeker gives one possible match in the Black Sea settlement region - Ladino / Lidino / Lidyne located about 40 km due north of Mariupol. If you have other family in that area, it might be a possibility.