pDENIM: towards a sustainable denim grown entirely from bacteria

 

dsc_0600

A sheet of bacterial nano cellulose observed under the microscope, 200x magnification

dsc_0597

A sheet of bacterial nano cellulose observed under the microscope, 200x magnification

The over arching aim of the pDENIM project (porkayoticDENIM) is to make a sustainable form of denim that is made and grown (both textile and dye), entirely from bacteria.

gxplate

An agar plate with a culture of the hyper cellulose producing bacterium GXCELL

The textile for pDENIM will be made using GXCELL a specialised hyper-nanocellulose producing bacterial strain isolated from a kombucha scoby. When this bacterium is grown in a liquid  mixture of vegetable extracts,  it forms mat of cellulose that are far thicker than many other strains of cellulose producing bacteria (see figures below)

compare

A comparison of cellulose production by GXCELL (left) and a normal cellulose producing bacterium (right). After 5 days incubation

 

 

gxdisc

A disc of bacterial cellulose produced by GXCELL

 

When the bacterial cellulose is dried it forms a thin and plastic-like film, which is brittle (see below) and clearly unsuitable for use as a  flexible textile such as denim.

_MG_6153

The dried form of bacterial cellulose

 

Dried.jpg

The dried form of bacterial cellulose

 

However, I have recently developed a process that converts the dried form of cellulose into a highly flexible textile, somewhere between paper and cotton (see below to see a refolded swatch of this material), and which will now become the bacterial fabric component pDENIM.

pap1

The new flexible form of bacterial nanocellulose

pap2

The new flexible form of bacterial nanocellulose

pap3

The new flexible form of bacterial nanocellulose

 

The other avenue of investigation for the pDENIM project seeks to find a sustainable and bacterially derived pigment to replace indigo, the dye used to stain denim blue. This dye  was traditionally extracted from plants of the genus Indigofera. Today, however, the several thousand tons of indigo used each year is synthetic and is produced by industrial processes with obvious consequences for the environment. Whilst many bacteria are pigmented  (e.g. red, purple, yellow and pink), those that produce strong blue pigments are rare. The first blue pigment bacterium that I investigated was Vogesella indigofera, a rare blue naturally pigmented bacterium that was originally isolated from a pond that had been used as a dump for highly toxic chemical waste (see below).

OLYMPUS DIGITAL CAMERA

A single colony of the blue pigmented bacterium Vogesella indigofera.

 

I find it intriguing that a life form so beautiful could arise from such a polluted environment. However, despite its beauty this bacterium was not a suitable replacement for indigo because its blue colour was too faint.

The second blue-pigmented bacterium that I characterised was Arthrobacter polychromogenes, which produces the water-soluble blue pigment, indochrome, together with the insoluble blue pigment, indigoidine (see below).

arth2

Colonies of the blue pigmented bacterium Arthrobacter polychromogenes.

arth4

Colonies of the blue pigmented bacterium Arthrobacter polychromogenes.

 

In the images below Arthrobacter polychromogenes has been grown on cotton and dyes it a deep blue. The next step will be mix the bacterially grown textile with the bacterially generated blue dye to make pDENIM. Watch this space……………..

denim

A swatch of cotton dyed blue by the growth of the bacterium Arthrobacter polychromogenes.

denim2

A swatch of cotton dyed blue by the growth of the bacterium Arthrobacter polychromogenes.

 

Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out / Change )

Twitter picture

You are commenting using your Twitter account. Log Out / Change )

Facebook photo

You are commenting using your Facebook account. Log Out / Change )

Google+ photo

You are commenting using your Google+ account. Log Out / Change )

Connecting to %s