Separation of health compounds in Goji (Lyceum barbarum) aqueous extracts by membrane technology

1. Separation of health compounds in Goji (Lyceum barbarum) aqueous extracts by membrane technology Carmela Conidi, Alfredo Cassano, Enrico Drioli Institute on Membrane Technology, ITM-CNR, c/o University of Calabria, via P. Bucci, 17/C I-87030 Rende (CS), Italy Phone: +39 0984 492067-492014 Fax: +39 0984 402103 E-mail: c.conidi@itm.cnr.it 2nd International Conference and Expo on Separation Techniques September 26 - 28, 2016 Valencia, Spain

2. Outline • Goji berries and leaves: state of the art and health properties • Membrane processes for the treatment of Goji berries and leaves aqueous extracts • Clarification of Goji aqueous extracts • Fractionation of clarified extracts • Analysis of membrane productivity • Analysis of membrane selectivity (antioxidant activity, total polyphenols, soluble solids, total carbohydrates) • Conclusions

3. State of art • Goji berries are one of the top 10 “Super Food” cultivated in the world • Popular in traditional Chinese medicine as well as Western parts of the world • The plant is also cultivated in the Mediterranean region (goji berries grow very well in regions with semi-arid to sub-tropical climatic conditions)

4. Global market of gojy extracts

5. Health benefits H. Amagase , N. R. Farnsworth. A review of botanical characteristics, phytochemistry, clinical relevance in efficacy and safety of Lycium barbarum fruit (Goji), Food Research International 44 (2011) 1702–1717

6. Bioactive compounds b-carotene Polyphenols Ascorbic acid Polysaccarides D. Donno, G.L. Beccaro, M.G. Mellano, A.K. Cerutti, G. Bounous. Goji berry fruit (Lycium spp.): antioxidant compound fingerprint and bioactivity evaluation, Journal Functional Foods, 2015, 1070-1085

7. Ultrafiltration • Nanofiltration • Reverse Osmosis ADVANTAGES Recovery of bioactive compounds from vegetable sources • Ultrasound assisted extraction • Solvent extraction • Resin-based extraction • Supercritical fluid extraction LIMITATIONS • low energy requirement • additive free (do not require the use of organic solvents) • mild operating conditions • preservation of thermo-sensitive compounds • more expensive than aqueous processing • residual solvents in the extracts (no desiderable for food use) • easy denaturation of thermo-sensitive compounds • reduction of nutritional value

8. Clarification/Fractionation with membranes processes Driving force = DP Permeate Retentate Membrane Feed Pressure-driven membrane processes UF

9. Gojiberriesextracts / flow sheet of the investigatedprocess Gojiberries Aqueous extract Sieving (200 mm) Washing Milling CLARIFICATION (UF) Retentate b-carotene Clarifiedextract Extraction with water (200 g/kg, 80 °C, 30 min) FRACTIONATION (UF/NF 0.5-2 kDa) Separation of carbohydrates from polyphenols

10. Clarification of gojiberriesextracts Toray HFS UF PS DCQ

11. Clarification of gojiberriesextracts Feed Permeate Retentate Ultrafiltration of goji berries aqueous extracts. Permeate flux vs. VRF (Operating conditions: TMP, 0.7 bar; Qf, 280 L/h; T, 24±2°C) FEED Permeate Retentate

12. Clarification of gojiberriesextracts PS membrane

13. Clarification of gojiberriesextracts PVDF membrane

14. Clarification of gojiberriesextracts Retention= (1-Cp/Cf)*100 b-carotene TSS TAA Total polyphenols Total carbohydrates Total suspended solids Retention of UF membranes towards analyzed compounds

15. Fractionation of clarifiedgojiberriesextracts Clarified goji berries aqueous extracts

16. Fractionation of clarifiedgojiberriesextracts Treatment of clarified Goji aqueous extracts with UF and NF membranes. Evolution of permeate flux as function of TMP (Operating conditions: Qf, 300, L/h; T, 24±2°C)

17. Fractionation of clarifiedgojiberriesextracts Retention of tested membrane towards total polyphenols Retention of tested membrane towards TAA Retention of tested membrane towards TSS Retention of tested membrane towards total carbohydrates

18. Fractionation of clarifiedgojiberriesextracts Retention of GK membrane towards analyzed compounds Retention of GH membrane towards analyzed compounds Retention of GE membrane towards analyzed compounds

19. Water UF permeate diafiltrate Desal GE Membrane Diafiltration/concentration Time evolution of permeate flux during diafiltration/concentration processes (Operating conditions: TMP, 10 bar; T, 27±1°C)

20. Diafiltration/concentration Analyses of TSS, total polyphenols, total carboydrates and TAA in samples of gojy berries extracts coming from the diafiltration/concentration processes *After 4.5 volumes of diafitration ** Weightreductionfactor (WRF) of 2

21. Goji leaves / Flow sheet of the investigated process Gojileaves Aqueous leaf extract Washing CLARIFICATION (UF 100 kDa) Retentate Clarifiedextract drying FRACTIONATION Extraction with water UP004 NP010 N30F Optimization extraction parameters (T, pH, solid/liquid ratio) (Mycrodin Nadir) flat-sheet Polyethersulphone MWCO = 4,000 Da (Mycrodin Nadir) flat-sheet Polyethersulphone MWCO = 1,000 Da (Mycrodin Nadir) flat-sheet Polyethersulphone MWCO = 0.300 Da

22. Optimization of extraction parameters Effect of concentration (solid/liquid ratio) on the TSS, Total polyphenols and TAA yields

23. . Optimization of extraction parameters mAU mAU mAU 800 800 800 700 700 700 600 600 600 500 500 500 400 400 400 300 300 300 200 200 200 100 100 100 0 0 0 0 5 10 15 20 25 30 35 40 min 0 0 5 5 10 10 15 15 20 20 25 25 30 30 35 35 40 40 min min Ethanol/water (1:1) extraction: concentration 10 g/Kg Aqueous extraction: concentration 10 g/Kg Aqueous extraction: concentration 100 g/Kg HPLC cromatograms of polyphenols in goji leaves extracts

24. Optimization of extraction parameters Effect of temperature of the extraction on the TSS and Total polyphenols yields

25. Optimization of extraction parameters Effect of the pH of the extraction solution on the TSS and Total polyphenols yields

26. Clarification of goji leaves extracts Ultrafiltration of goji leaves extracts. Time course of permeate flux and VRF (Operating conditions: TMP, 0.7 bar; Qf, 280 L/h; T, 24±2°C)

27. Fractionation of clarifiedgojileavesextracts Treatment of clarified leaves aqueous extracts with UF and NF membranes . Evolution of permeate flux as function of TMP (Operating conditions: Qf, 300 L/h; T, 24±2°C)

28. Fractionation of clarifiedgojileavesextracts Retention of NP010 membrane towards analyzed compounds Retention of UP004 membrane towards analyzed compounds Retention of N30F membrane towards analyzed compounds

29. Fractionation of clarifiedgojileavesextracts Analyses of total polyphenols, TAA, total soluble solids and total carbohydrates in goji leaves samples from NPO10 membrane at different WRF Retention of NPO10 membrane towards analyzed compounds

30. Conclusions • A combination of aqueous extraction and membrane-based purification processes of bioactive compounds from Goji berries and leaves has been studied and optimised. • The PVDF UF membrane allows to separate b-carotene in Goji berries aqueous extracts with high efficiency in terms of retention (98%) and productivity (more than 40 kg/m2h). • Operating conditions (pH, temperature, concentration) for the aqueous extraction of goji leaves have been optimized. • In the fractionation of both clarified extracts permeate fluxes increased linearly with the operating pressure. At low pressure values a better separation of antioxidant compounds (including polyphenols) from carbohydrates and TSS has been observed. • The sugar purification can be improved significantly if diafiltration is applied. • A strict correlation between the MWCO of selected membranes and the retention of investigated compounds has been detected.

31. Tank you…for your kind attention!