You could use something like this: 
    #!/usr/bin/perl -w

    use strict;

    my $line = "Hello world [Pyruvate] [pyruvate]\n";

    $line =~ s/\b(\w+)\b/\l$1/g;

    print $line;

    __END__

    prints:

    hello world [pyruvate] [pyruvate]

[download]

However, this may be overkill if you can just lc() the entire line.

--
John.

In reply to Re: Regexes for Case Change by jmcnamara
in thread Regexes for Case Change by arunhorne

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