Klarinet Archive - Posting 000136.txt from 1999/12

From: "Mark Charette" <charette@-----.org>
Subj: [kl] Reeds and Saliva
Date: Sat, 4 Dec 1999 22:15:03 -0500

A couple more from the archives, slightly more technical:
=================
Date: Thu, 20 Mar 1997 11:09:51 CST
From: "Diane Karius, Ph.D." <dikarius@-----.EDU>
Organization: University of Health Sciences
Subject: Re: Water vs Saliva for wetting reeds

I'll give everyone the punch line up front (then you can decide if
you want to read the science below!): Saliva probably ISN"T good for
our reeds, but (as Mr. Schmidt pointed out) probably not for the most
commonly cited reasons.
Regarding the pH of saliva: Mr. Schmidt is absolutely right - cells
of the salivary gland ADD bicarbonate to the saliva - giving the
saliva a basic pH. I wouldn't be surprised if the pH while you were
actually playing wasn't even more basic than the 7.2 that Mr.
Schmidt measured since the presence of the mouthpiece/reed in the
mouth is a stimulus for salivary secretion and that increases the pH
even further (probably to a pH 8 or so). One should note that it is
possible that the basic pH is doing as much damage to the reed as
it was assumed an acid pH could do.
Mr. Schmidt is also right regarding the ability of salivary
amylase (the enzyme in saliva) to work on cane. The sugars in
wood/cane are bound to one another using a linkage called a "beta-1,4".
Amylase is unable to work on anything other than an "alpha-1,4"
linkage (hence the existence of "dietary fiber"!).
A major component of saliva is mucus - between the physical
presence of the enzymes (even if they can't do anything chemical to
the cane) and the mucus, once the watery portion of the saliva
dries away, the mucus and the enzymes are left behind to physically
interfere with the reed. As a medical example of how thick these two
are (and damaging) - most of the symptoms of cystic fibrosis are the
result of the mucus (and in the GI tract, the enzymes) not getting
mixed with watery secretions. This renders them very thick and they
plug up the airways/pancreas.
Diane R. Karius, Ph.D.
Department of Physiology
University of Health Sciences
2105 Independence Ave.
Kansas City, MO 64124
email: dikarius@-----.EDU
========================
Date: Fri, 21 Mar 1997 14:35:15 CST
From: "Diane Karius, Ph.D." <dikarius@-----.EDU>
Organization: University of Health Sciences
Subject: Re: Diana K's message on enzymes

> Roger Shilcock wrote:
>
> > See Diana K's messgae re amylase linkages - I suspect she doesn't
actually
> > mean cellulose.
>
> Diana? Are you reading this? When you made the statement
> concerning the indigestibility of wood, were you not referring
> specifically to cellulose -- hence the dietary fiber joke?
> Or were you referring to a different substance present in
> the cane from which woodwind reeds are made?
>
sorry for not answering - too many committee meetings (who needs to
get real work done when you can have a committee :-)!) I was referring
specifically to cellulose which is the primary component of the cell
wall which surrounds a plant cell membrane (which would include cane).
Just to make sure I said it right: Amylase will only cleave an bond
between sugars that are linked in an "alpha-1,4" arrangement.
Animal carbohydrates link sugars using this arrangement.
Plants do it differently: Cellulose is made by linking
the sugars in a "beta-1,4" . The two sugars are still bond together
between carbon #1 of the first sugar and carbon #4 of the second, but
the bond has a different "shape" This puts the sugars in a different
conformation and amylase cannot get to the bond to split it apart.
Have I confused you thoroughly?
Diane R. Karius, Ph.D.
Department of Physiology
University of Health Sciences
2105 Independence Ave.
Kansas City, MO 64124
email: dikarius@-----.EDU

---------------------------------------------------------------------
Unsubscribe from Klarinet, e-mail: klarinet-unsubscribe@-----.org
Subscribe to the Digest: klarinet-digest-subscribe@-----.org
Additional commands: klarinet-help@-----.org
Other problems: klarinet-owner@-----.org