Xylose Lysine Deoxycholate (XLD) Agar is a selective and differential medium used to isolate enteric pathogens — especially Salmonella and Shigella — from stool cultures. Let’s decode what you see on the plate 👇 #Salmonella Ferments xylose → turns yellow at first Then decarboxylates lysine → reverts to red Produces H₂S → black centers 👉 Result: Red colonies with black centers #Shigella Doesn’t ferment xylose No H₂S production 👉 Result: Red colonies without black centers #Ecoli (or other colif

33 reactions · 11 shares | The Transportation Security Administration on Wednesday began enforcing new rules requiring air travelers to present a Real ID or other federally approved form of identification to board domestic flights. But even as the mandate took effect, it appeared grace was issued at Minneapolis-St. Paul International Airport. Tap the link in our bio for the full report by Tim Harlow.  @leilanavidi/The Minnesota Star Tribune | Star Tribune | Facebook