Archives for the month of: July, 2013

Welcome back to our Mycotoxin Series!

With wheat harvest mostly complete for the eastern United States, it only seems fitting that I write about deoxynivalenol (DON).  DON is produced by Fusarium graminearum (amongst others) and can be found in products made with wheat, barley and corn.  DON has been dubbed the “most commonly encountered” mycotoxin.  This is likely due to our diets (wheat and corn are staple crops in many cultures and are used in many food products) and much of the wheat we grow is rather susceptible to F. graminearum.

 FHB wheat head katelynwillyerd

F. graminearum is the causal agent of Fusarium head blight of small grains (also known as Scab).  The disease is characterized by premature “bleaching” of the wheat heads (see above), shriveled kernels, reduced yield and DON contamination.  F. graminearum also causes a disease in corn called Gibberella ear rot (more of a concern for livestock).  DON serves as a virulence factor for F. graminearum which means DON is a powerful “weapon” for this pathogen as it infects the plant.

DON is a mycotoxin that is harmful to both plants and animals (any eukaryotic cell, for that matter).  DON binds to ribosomes, preventing cells from translating genes to proteins (remember, Bio 101: DNA –> mRNA –> amino acids/proteins).  Without essential proteins, cells are unable to carryout basic function and die (e.g. bleached, dead tissue on wheat heads).

DON is also known as “vomitoxin”.  This gives you a pretty specific idea about what sort of symptoms we observe in humans and animals suffering from DON poisoning.  DON may also cause other gastro-intestinal distress, poor nutrient absorption, reduced weight gain, feed refusal and impaired immunity.  Despite being the most commonly encountered mycotoxin, we don’t have a good handle on the effects of chronic exposure to low doses of DON that may be in our breakfast cereals, breads, pretzels, pastas, etc.

DON facts katelynwillyerd

PS – A fact sheet I co-wrote on DON in corn in Ohio

…pick me a snake berry?!  More on that below…

I’m a big proponent of eating seasonally, primarily eating what’s ripe when it’s ripe and avoiding what isn’t ripe or “in season”.  Maybe it comes from growing up on an apple farm.  I just can’t bring myself to buy apples from a store in the spring because I know they won’t be as good as the fresh fall apples I remember.  Summer berries have an especially short window, and right now wild black raspberries are in season on our farm.

rubus_occidentalis3_katelynwillyerd

Rubus occidentalis is native to eastern North America and one of the most common Rubus species yet is not typically planted.

rubus_occidentalis2_katelynwillyerd

Botany Lesson: Like all raspberries, the fruits are multiples of drupes.  A drupe is a seed surrounded by a fleshy outer tissue.  A raspberry is an aggregate of many druplets, hence containing many seeds.  A peach, for example, is a single drupe: It contains one seed/pit and is surrounded by the part that we eat.  In nature, animals are attracted to this fleshy tissue and help with the dispersal of the seeds as they consume or transport them.

rubus_occidentalis1_katelynwillyerd

Admittedly, the wild black raspberries are more “seedy” and smaller than cultivated varieties, but they are still great on cereal or ice cream (or by the handful).  Not to mention free, “organic”, and you never know when you might see a snake slither out of the bramble…  Unfortunately, I did NOT get a photo as I was more concerned with keeping my dog away.  It was most likely a black rat snake, and easily the longest snake I’ve seen in the wild around here!

What’s your favorite summertime fruit?  Or fruit/veg/fungus you scout for and harvest from the wild?

PS – A wild black raspberry fact sheet