The Potential for Bacteriophage to Control Post-Harvest Soft Rot Development
DR ALISON BLACKWELL, APS BIOCONTROL LTD.
EAPR Post Harvest 28 - 30 June 2016
APS BIOCONTROL LTD.
 Dundee-based APS Biocontrol is an innovative biocontrol company, developing
technologies which address an increasing need for effective and
environmentally-sustainable replacements for synthetic chemicals
 APS’ core technology is based on bacteriophage; naturally-occurring, safe
antimicrobials
 The technology is being developed in a number of market sectors, with the lead
product, Biolyse® being a world first; a bacteriophage-based solution for use
post harvest and in particular, for washed and packed fresh produce
WHAT ARE BACTERIOPHAGE?
 The most abundant organisms in the world (1031 on
Earth)
 Naturally abundant in soil, water, sewage, animals
 Natural enemies of bacteria & all bacteria have these
enemies
 Kill bacterial cells in a highly specific manner
 Completely harmless to the surrounding environment
 Can be exploited as ‘natural antimicrobials’
WHAT ARE BACTERIOPHAGE?

Advantages over mainstream pesticides/biocides:




safe: naturally-occurring (food, water, soil etc) and highly specific
(will not infect beneficial bacteria), with zero non-target risks and
environmental residues
applicable to both mainstream & organic agriculture (organic approvals
in both the EU & USA)
the right mix of bacteriophages is highly effective
continue to work long after chemicals have lost their potency
BACTERIOPHAGE

Current commercial bacteriophage products for use with food:




ListexTM P100 (EBI Food Safety, The Netherlands): targeting Listeria
monocytogenes on cheese, meat, fish
SalmonelexTM (EBI Food Safety, The Netherlands): targeting
Salmonella contamination of meet post-slaughter
Biolyse® (APS Biocontrol, UK): targeting spoilage pathogens
(Pectobacterium, Dickeya) of washed, packed potatoes
All are marketed as ‘processing aids’:

‘…….any substance not consumed as a food by itself, intentionally used in the
processing of raw materials, foods or their ingredients, to fulfil a certain
technological purpose during treatment or processing, and which may result in
the unintentional but technically unavoidable presence of residues of the
substance or its derivatives in the final product, provided that these residues do
not present any health risk and do not have any technological effect on the
finished product.’
BACTERIAL SPOILAGE OF POTATOES
 Bacterial rots: greatest challenge to fresh produce
growers & processors
 all stages of the growing cycle are affected
 EU industry: fierce competition & rising costs
 Current control (where it exists): chemical biocides of
limited effectiveness
 Could bacteriophage provide a competitive
advantage to the industry as safe, effective and
sustainable alternatives?
OPTIONS FOR BACTERIOPHAGE APPLICATION
The challenge: developing an innovative, sustainable and environmentallysound bactericide treatment that is applicable across the potato industry
The Biolyse® story
HOW DO WE ISOLATE BACTERIOPHAGE?
Bacterial
Isolation
Isolate Lytic
bacteriophage
Enrichment
Screened for broad
range activity and
accepted or rejected
Scale up
BIOLYSE®
A first bacteriophage-based processing aid for fresh produce, targeting
only the harmful, soft rot-causing Pectobacterium & Dickeya bacteria on
potatoes & and providing significantly greater control than existing
chemical products
 Composition: a minimum of 5 x 107 PFU/ml, with a recommended
working application rate of 5 x 104 PFU/ml
 A bacteriophage mixture covering up to 90% of rot-causing
bacteria isolated (in the UK), with regular monitoring of the mix
efficacy
BIOLYSE® APPLICATION
Washer barrel tubers
Washer barrel
Biolyse® treated tubers
Water spray post
washer barrel
Biolyse® mist prepacking (5 nozzle
spray bar each @
0.065 L/min)
BIOLYSE® EFFICACY: THE EVIDENCE
Untreated
Water rinsed
Reduced shelf-life failures,
depot rejections & customer
complaints
INDUSTRY SHELF-LIFE DATA
Logan Estima
(packing +7 days)
Untreated
INDUSTRY SHELF-LIFE DATA
Crombie Desiree
(packing +2 days)
Untreated
INDUSTRY SHELF-LIFE DATA
Four-year shelf-life failure data,
comparing untreated & Biolyse®treated tubers at day 6 after
packing
40%
% Shelf-life failures due to rots
35%
30%
25%
Untreated shelf-life failures
at day 6
20%
Biolyse® treated shelf-life
failures at day 6
15%
10%
5%
0%
2012 (n = 346)
2013 (n = 1334)
2014 (n = 497)
2015 (n = 339)
FEEDBACK FROM THE RETAILER
Retailer customer potato complaints (variety: Jersey): % due to “rots”
Supplier A:
chemical biocide
Supplier B:
chemical biocide
Supplier C:
Biolyse®
Customer complaints due to rots
decrease significantly when the supplier
uses Biolyse® to reduce soft rot damage
SUMMARY
 Bacteriophage have significant potential for the specific control of
spoilage pathogens of fresh produce
 The variability of plant pathogens complicates issues and requires a
mixture of bacteriophage to provide sufficient pathogen control
 We many need different mixes from different geographical regions – we
NEED your rotting potatoes!
 A bacteriophage mix (Biolyse®) is in routine use by the packing
industry and microbiological evidence of lower bacterial counts
following Biolyse® treatment is backed up by both industry and retail
customer data
 Soft rot control at other points in the growing cycle are actively being
investigated, with promising results. Treatments include those aimed
at reducing the overall pathogen loading of seed and reduction of
inoculum on the crop, together with applications in-store.
CONTACT
Dr Alison Blackwell
APS Biocontrol Ltd.
Prospect Business Centre
Gemini Crescent
Dundee DD2 1TY
Tel. +44 1382 561 696
[email protected]