Old German Bonds From 1928 - Any Value?

Hello everyone!
I would appreciate it if someone could help with advice - is it hypothetically possible that these 1928 German bonds have any value to be sought from the issuer? There are a total of 20 pieces, with a denomination of 500 and 1000 marks, and they have neither perforations nor a seal to show that they have been paid.
I don't understand much about this stuff so it might be stupid on my part :))

A few things: 1) they certainly have value for historical and collectible reasons, both of which I think are obvious; 2) bonds of any kind are generally of no financial value almost a century after issue, anywhere in the world (as financial instruments the most always have an expiration date or sunset provision whether explicit or implied by law, or the issuing entirety ceases to exist, etc which leads me to my third); 3) these were issued in 1928 by the Jewish Community of Frankfurt, Germany, read the italicized words once or twice, and the reason why these couldn't be cashed in with the issuer should hit you like a truck.