Rapid Detection of Walnut oil by FTIR and Bioactivities of Walnut Protein Hydrolysates

Transcription

1 Rapid Detection of Walnut oil by FTIR and Bioactivities of Walnut Protein Hydrolysates Jie Ouyang Espoo Finland, Nov 12, 2013

2

3 Walnut distribution in China and the World:

4 Area (Acre) Production (Ton) World 3.0 m 1.7 m China 1.7 m 1.0 m

5 Walnut distribution in China:

6

7 In walnut: oil: 60-70% protein: ~20% Walnut oil processing machine

8 1 Authentication and adulteration of walnut oil 2 Utilization of remained walnut protein

9 1 Authentication and adulteration of walnut oil Authentication of walnut oil by GC (Gas Chromatography) Authentication of walnut oil by FTIR-PCA (Fourier Transform Infrared Spectroscopy combined with Principal Component Analysis) Adulteration of walnut oil by FTIR-PLS (Partial Least Square)

10 1.1 Authentication of walnut oil detected by GC Fatty acids Walnut oil Olive oil Soybean oil Sunflowerseed oil Peanut oil C16:0 6.0~ ~ ~ ~ ~10.0 C16:1 0.1~ ~ C18:0 2.0~ ~ ~ ~ ~10.0 C18:1 11.5~ ~ ~ ~ ~10.0 C18:2 50.0~ ~ ~ ~ ~10.0 C18:3 6.5~ ~ (From Chinese Standards on edible oils)

11 Fatty acids Walnut oil Standard Sample 1 Sample 2 Sample 3 Sample 4 Walnut oil has high content of linoleic acid (60-65%) and linolenic acid (6.5-10%), higher than those in other oils. Ratio of linoleic acid to oleic acid in walnut oil is between 3.1 and 4.0.

12 GC of qualified walnut oils based on fatty acids

13 GC analysis FTIR analysis Classic method Relatively new analysis method Clear and easy to be understood Combined with chemometrics Requiring derivatization Little sample preparation Time-consuming Minimizing hazard solvent Trained techinician Simple experimental procedure Rapid Cost saving

14 1.2 Qualitative detection on authenticity of walnut oil by FTIR-PCA Materials 7 walnut oil, 5 soybean oil, 5 peanut oil, 5 canola oil, 5 blended oil, 5 sunflower oil FTIR Nicolet is5 FTIR

15 x dd-1 x dd-2 Model samples 0.14 A cm-1 FTIR spectrum Reference Analysis E s t im a t e d x 20 b17 b18 a17 a18 b19 a19 a11 a12 a13 x b13 a15 a14x c15 c16 d17 d18 c17 c18x x d19 d20 c19 b15 b16x a16 a3 a4 a2 a1 a5 a6 a7 a8x b10 a9 b11 b12 b2 b1 b3 b4 b5 b6x b7 b8x b9 c10 c11 c13 c2 c3 c4 c5 c6x c7 c8x x d10 c9 x d11 d12 x d13 x d2 d1 x d3 d4 x d5 d6x x d7 d8x d9 c1-6.3 x d29 d30 c29 c30 b30 a29 a30 x d28 c28 a27 a28 x d25 d26 b25 b26 a26 x c23 c24 a23 x d21 d22 c22 a Specified Modeling q z m x - k14 x - d01 x - d26 d14 x - h12 x - k02x - x k09 - x k06 d09 x x - h08 - k11 h02 - h06 x -- h14 d03 x - d05 x - h04 x - z08 x - z11 x - z13 x - - z17 z31 x x - - z34 z24x - z04 x - z fzm Discrimination 1.60 (-C=O) (-CH2-asymmetric) (C-O) A (-CH2-symmetric) 2853 (cis C=CH) 3009 (C-O) 1119 (cis CH=CH) (C-O) (-CH2) (C-O) (Trans (-CH3) CH=CH) (cis C=C) (C-O) (cis C=CH) cm-1 Test samples FTIR spectrum Model prediction Quantification

16 FTIR spectrum of edible oil: FTIR

17 original S-G smoothing Normalize FD SD MSC SNV

18 PCA:Principle Component Analysis PLS: Partial Least Square MLR:Multivarate Linear Regression PCR:Principle Component Regression ANN: Artificial Neural Net

19 FTIR spectra of walnut oil and other oils: Abs Walnut oil Soybean oil Sunflower oil Conala oil Peanut oil Blended oil cm

20 The second derivative of FTIR spectra of walnut oil and other oils: Walnut oil Soybean oil Sunflower oil Abs Conala oil Peanut oil Blended oil cm-1

21 The PCA graph of walnut oil and other oils: sss s s s s s sss s d d d d d b b d b d b b b b c c p p c c p p p pp pp p c c cc cc ccc c -1 d bbb b d w ww ww w w -5 w w w w w w ww w w PC-1 (84%)

22 PCA Classification model of the walnut and other oils with SNV and the first derivative: 0.1 peanut oil 0 w ww ww w w w ww ww w w Walnut oil sunflower oil ss s ss s d b d d dd d d b bb b b cc cc soybean oil c p p p p p p c cc cc c c PC-1 (90%) X-variables (PC-1) (90%) 2e-07 1e-07 d d d b w d b w d d bw w w b b d b b w wb wb w p c s s w s b s s s p p s s s p p p p w w w w c Leverage (PC-5) c c c c c c c PC-0 PC-1 PC-2 PC-3 PC-4 PC-5 PC-6 PC-7 PCs

23 Conclusion After the first derivative spectrum treatment, walnut oil had no overlap with other oils and they didn t disturb each other. The FTIR-PCA classification model of walnut oil and other oils was practical.

24 1.3 Quantitative detection on adulteration of walnut oil by FTIR-PCA Walnut oil adulterated with soybean oil: % 40% 50% adulteration ratio respectively Walnut oil adulterated with peanut oil: % 40% 50% adulteration ratio respectively Totally 32 samples were prepared and used as calibration set among them 10 samples were used as validation set.

25 Soybean oil-walnut oil Peanut oilwalnut oil Walnut oil Fig. PCA classification of walnut oil and adulterated walnut oil

26 Conclusion The determination limits of soybean oil adulterated in walnut oil by PCA was 5%; The determination limits of peanut oil adulterated in walnut oil by PCA was 10%.

27 1.4 Quantitative detection on adulteration of walnut oil by FTIR-PLS Table Three pretreatment methods for FTIR spectra Pretreatment oils principal components Original Soybean oil Peanut oil Soybean oil Peanut oil Soybean oil Peanut oil After normalization, RMSEC of calibration and RMSECV of validation were decreased and R 2 reached 1.0.

28 Soybean oil adulterated in walnut oil PLS regression calibration curve

29 peanut oil adulterated in walnut oil PLS regression calibration curve

30 Predicted results of adulterant amount of walnut oil with soybean oil and peanut oil Adulterant amount Soybean oil predicted value (%) Deviation Adulterant amount peanut oil predicted value (%) Deviation

31 Conclusion Partial least square (PLS) analysis was used to establish a binary system of adulteration content of walnut oil. Soybean oil and peanut oil volume fraction by PLS calibration model with R 2 and RMSEC value were , and , respectively. Deviation between predicted and reference value was , which is insignificant and means the calibration model is practical.

32 2. Bioactivities of walnut protein and hydrolysates 2.1 Separation and purification of angiotensin -converting enzyme inhibitor from walnut protein 2.2 promotion of spleen lymphocyte and macrophage functions induced by neutral protease hydrolysate of walnut protein 2.3 Inhibition of proliferation induced by papain hydrolysate of walnut protein on tumor cells

33 2.1 Separation and purification of angiotensin converting enzyme inhibitor from walnut protein ACE inhibitor was purified step by step; Walnut protein was hydrolyzed by pepsin; Inhibitory activity of 1mg/mL hydrolysate was 20.79%; Among them, faction 0-5kDa was better than 5-10 kda. MW range (kda) IC 50 ( g/ml) 40.00± ±0.02

34 Fraction 0 5 kda was Gel filtrated by Sephadex G-25, and four peaks P1,P2, P3, P4 obtained IC50(mg/mL) ACE inhibitory efficiency of P3 was the hightest and IC50=23.4 g/ml P1 P2 P3 P4

35 Then P3 was seperated by Superdex peptide 10/300 three fractions P3-1, P3-2, P3-3 were obtained IC50 g/ml P3-1 P3-2 P3-3 P3-3 showed the hightest ACE inhibitory efficiency.

36 P3-3 was further purified by Reverse HPLC Zorbax SB- C18 the IC 50 of ACE inhibitory efficiency was 0.32 g/ml Structure of P3-3 was sequenced as Tyr-Glu-Pro

37 Digestion Stability of ACE inhibitory peptide Tyr-Glu- Pro from walnut protein hydrolysate Before digestion After digestion IC 50 g/ml) 0.32± ±0.02

38 2.2 Promotion of spleen lymphocyte and macrophage functions induced by protease hydrolysates of walnut protein Walnut protein hydrolysates were prepared with pepsin, trypsin, alkaline protease, papain and neutral protease respectively Bioactivities of walnut protein and its hydrolysates on spleen lymphocyte and macrophage function.

39 % * * * 120 % of control Control Total Alkaline Neutral cona protein protease protease Con A pepsin papain trypsin

40 70 IL-2 pg/ml % 10 0 Control Total Alkaline Neutral cona protein protease protease Con A pepsin papain trypsin Effect of walnut protein and its hydrolysates (0.5 mg/ml) on IL-2 secretion of spleen lymphocyte

41 Effect of walnut protein and its hydrolysates (0.5 mg/ml) on macrophage phagocytosis % 200 ** ** ** % of control * * 50 0 Control Total Alkaline Neutral protein protease protease pepsin papain trypsin

42 Effect of walnut protein and its hydrolysates (0.5 mg/ml) on NO production by macrophage * 20.4 % * % of control Control Total Alkaline Neutral protein protease protease pepsin papain trypsin

43 Walnut protein and its hydrolysates could promote the function of spleen lymphocyte and macrophage; The hydrolysates showed stronger effects than walnut protein, in which neutral protease was the strongest.

44 2.3 Inhibition of proliferation induced by hydrolysates of walnut protein on tumor cells Three kinds of tumor cells were used human breast cancer cells MCF-7 human colon carcinoma cell Caco-2 human cervical carcinoma cell Hela rat small intestinal crypt epithelial cell ICE-6, not tumor cell

45 IC mg/ml Walnut papain pepsin trypsin Neutral Alkaline protein protease protease

46 IC mg/ml Inhibition of proliferation induced by papain hydrolysates of walnut protein on Caco-2

47 IC mg/ml Inhibition of proliferation induced by papain hydrolysates of walnut protein on Hela

48 Inhibition of proliferation induced by papain hydrolysates of walnut protein on non-tumor cell IEC-6

49 Effect of walnut protein papain hydrolysates (0.5 mg/ml) on spleen lymphocyte proliferation

50 Papain hydrolysates of walnut protein showed significant inhibition on the proliferation of tumor cell MCF-7, Caco-2 and Hela; Papain hydrolysates of walnut protein showed insignificant inhibition on the proliferation of non-tumor cell IEC-6, but could promote the proliferation of spleen lymphocyte.

51 Research Team Jie Ouyang, PhD & Assoc. Prof. of food science, Mainly focused on forestry food processing and safety, including edible woody-oils, natural food additives. Meiyu Xu, PhD & Assoc. Prof. of food science, Mainly focused on biological functions of protein from food, such as apricot kernel, walnut, milk Post graduates: Li Cui, Mengxin Zai, Haixia Wang, Xianhe Shi, Dan Zhou, Qiaojiao Zhao