1. Valorisation of rapeseed meal for microbial astaxanthin production
Department of Food and Nutritional Sciences
Valorisation of rapeseed meal for microbial astaxanthin production
Zuharlida Tuan Harith, A. Chatzifragkou, D. Charalampopoulos
University of Reading

2. Food processing industry Out of date fruits/vegetables
BIOREFinery concept
Agriculture waste
Food processing industry
Municipal waste
Out of date fruits/vegetables
Bioprocessing
bioplastics
biofuel
Pharmaceuticals
Cosmetics
Biorefining is the sustainable processing of biomass into a spectrum of marketable products and energy”
The biorefinery concept embraces a wide range of technologies able to separate biomass resources (wood, grasses, corn…) into their building blocks (carbohydrates, proteins, triglycerides…) which can be converted to value added products, biofuels and chemicals. A biorefinery is a facility (or network of facilities) that integrates biomass conversion processes and equipment to produce transportation biofuels, power, and chemicals from biomass. This concept is analogous to today’s petroleum refinery, which produces multiple fuels and products from petroleum.
Francesco Cherubini (2010)
Feed
Chemicals

3. Rapeseed cultivation Brassica napus L
UK is the 3rd largest producer after Germany and France
700, 000 ha of UK land used for rapeseed cultivation annually
Major oilseed cultivated in the EU
Products: oil, biodiesel, engine lubricants
Brassica napus L

4. Rapeseed meal (RSM) Value Production: 39.67 Mt per annum
Price: $226/ton
Current applications
Feed
Fertiliser
Compost
Opportunity
Protein source
Microbial conversion

5. RSM composition
Rapeseed meal – rich in protein, cellulose, hemicellulose
Need to be hydrolysed into assimilable, simple sugars and amino acids
Lignocellulosic biomass has three major components: cellulose, hemicellulose and lignin. Cellulose (C6H10O6)n has a strong molecular structure made by long chains of glucose molecules (C6 sugar).
Hemicellulose (C5H8O5)n is a relatively amorphous component that is easier to break down with chemicals and/or heat than cellulose; it contains a mix of C6 and C5 sugars. It is the second main component of lignocellulosic biomass (20–40% of total feedstock dry matter).
Lignin (C9H10O2(OCH3)n), is essentially the glue that provides the overall rigidity to the structure of plants and trees and is made of phenolic polymers. While cellulose and hemicellulose are polysaccharides that can be hydrolyzed to sugars and then fermented to ethanol, lignin cannot be used in fermentation processes, but it may be useful for other purposes (chemical extraction or energy generation). Lignin (15–25% of total feedstock dry matter) is the largest non-carbohydrate fraction of lignocellulose.
Basic plant cell wall structure

6. One of most important carotenoids
Market – projection 1.1 billion USD in 2020 (MRPD, 2015)
Found in salmon, crustaceans, trouts, flamingo – sourced through diet
Sources:
Haematococcus pluvialis;
Xanthophyllomyces dendrorhous;
synthetically produced via Wittig reaction & Grignard reaction
Shrimp shells from shrimp processing waste
Benefits:
antioxidant , Vitamin A precursor, food colourant

7. The Yeast Aim of study Xanthophyllomyces dendrorhous DSMZ 5626
Previously known as Phaffia rhodozyma
Major producer of astaxanthin-90% of total carotenoids
Aim of study
To investigate the feasibility of microbial astaxanthin production
by Xanthophyllomyces dendrorhous DSMZ 5626 using rapeseed
meal hydrolysates as fermentation nutrients.

8. Research scheme

9. GROWTH OFX. dendrorhous on refined sugars
Carbon source (30 g/l)
Time (h)
Biomass
(g/l)
Ast
(mg/l)
Y Ast/x
(mg/g)
Y Ast/s (mg/g)
µmax
(h-1)
Cellobiose
120
13.3 (0.2)
4.24 (0.22)
(11.8)
0.14 (0.01)
0.19
Xylose
112
12.8 (0.2)
3.76 (0.19)
(10.1)
0.15 (0.01)
0.17
Fructose
11.1 (0.0)
3.47 (0.02)
(2.07)
0.13 (0.01)
Arabinose
115
10.7 (1.2)
1.87 (0.02)
(1.23
0.07 (0.01)
0.11
Galactose
13.3 (1.3)
0.57 (0.04)
46.51 (3.23)
0.12 (0.01)
0.12
Glucose
117
9.13 (0.6)
2.32 (0.03)
255 (15)
0.08 (0.01)
0.16
Glycerol 88
8.55 (0.2)
2.88 (0.01)
337 (5.0)
0.16 (0.01)
0.13

10. GROWTH OFX. dendrorhous on refined sugarsB
Specific growth rate, µ (h-1) of X. dendrorhous when cultivated using different initial concentrations of (A) glucose and (B) glycerol.

11. Rapeseed MeAL COMPOSITION

12. Enzymatic hydrolysis of Rapeseed MeAL
Effect of different enzyme concentrations on sugar release after 24 h of reaction using Viscozyme (A), pectinase (B), Acellerase 1500 (C )and cellulase (D)

13. X. dendrorhous GROWTH PROFILE IN BIOREACTOR
X. dendrorhous cultivated in pectinase-derived rapeseed meal hydrolysate

14. Rapeseed MeAL hydrolysates as substrates
A. Batch flask:
RSM hydrolysate
Time
(h)
Biomass
(g/l)
Ast
(mg/l)
YAst/x
(mg/g)
EtOHmax
Viscozyme L
115
3.07 ± 0.07
0.4 ± 0.03
156 ± 11.75
3.8 ± 0.13
Cellulase
14.63 ± 0.64
1.10 ± 0.18
71 ± 11.4
6.92 ± 0.00
Pectinase
120
25.83 ± 1.52
6.71 ± 0.44
258 ± 1.83 -
Acellerase
118
8.2 ± 0.01
2.69 ± 0.05
332 ± 12
2.02 ± 0.15
B. 2-L batch bioreactor:
RSM hydrolysates
Time
(h)
Biomass
(g/l)
Ast
(mg/l)
YAst/x
(mg/g)
Cellulase
120
25.3 ± 0.28
7.66 ± 0.04
± 1.69
Pectinase
39.75 ± 0.07
10.78 ± 0.15
± 4.23
Acellerase
112
14.3 ± 0.85
3.59 ± 0.14
± 5.23

15. conclusions
Rapeseed meal is a rich by-product that can be valorised for the production of high value pigments via microbial conversion.
Screening of enzymes is essential in determining the hydrolysis rate of rapeseed meal.
The production of microbial pigments using renewable biomass residues is feasible. Its optimisation could replace the domination of synthetically produced astaxanthin.

16. Thank you