Biological activities and characterization of polysaccharides from the three Australian Sweet Lupins

Figures & data

Table 1. Extraction Yield, carbohydrate, and protein contents of sweet lupin polysaccharides

Lupin	Polysaccharide yield	Carbohydrate content (%)	Protein content (%)
Blue lupin	99.63 g/kg	54.63	44.36
White lupin	45.62 g/kg	59.42	39.86
Yellow lupin	35.98 g/kg	52.74	46.24

Table 2. Monosaccharide composition of different lupin polysaccharides

Monosaccharide (%)	Blue lupin (BLP)	White lupin (WLP)	Yellow lupin (YLP)
Galactose	51.90	49.15	37.70
Mannose	21.65	24.31	15.03
Xylose	7.11	8.42	21.81
Rhamnose	8.21	-	-
Glucose	7.63	12.45	14.62
Fucose	3.50	5.67	10.84

Figure 1. SEM images of white (top), yellow (middle) and blue (bottom) lupin polysaccharides

Table 3. Decomposition patterns of lupin polysaccharides

	Decomposition stage-1		Decomposition stage-2		Decomposition stage-3
Polysaccharide	Loss of absorbed and bound water (°C)	Weight loss (%)	Major weight loss due to decomposition and loss of CO, CO2 and H2O (°C)	Weight loss (%)	Final decomposition stage (°C)	Weight loss (%)
Yellow lupin	62.83–163.17	6.56	163.17–339.62	31.38	339.62–588.27	36.81
White lupin	60.49–161.54	6.58	161.54–359.48	42.26	359.48–587.61	29.37
Blue lupin	65.34–179.63	7.18	179.63–403.65	46.16	403.65–589.35	17.26

Figure 2. FT-IR spectrum of white lupin polysaccharides. Relevant vibrational peaks in the spectrum are represented with numbers 1 to 11 (Peak 1: 797 cm⁻¹; Peak 2: 837 cm⁻¹; Peak 3: 881 cm⁻¹; Peak 4: 919 cm⁻¹; Peak 5: 1021 cm⁻¹; Peak 6: 1048 cm⁻¹; Peak 7: 1078 cm⁻¹ Peak 8: 1533 cm⁻¹; Peak 9: 1626 cm⁻¹; Peak 10: 2928 cm⁻¹ and Peak 11: 3274 cm⁻¹)

Table 4. Antioxidant activities of polysaccharides from white, yellow, and blue lupins

Lupin	IC50 value of ABTS^•+radical scavenging activity (mg/mL)	IC50 value of Hydroxyl radical scavenging activity (mg/mL)	IC50 value of Ferrous chelating activity (mg/mL)
Blue	2.65 ± 0.21	1.56 ± 0.32	3.51 ± 0.51
White	2.13 ± 0.18	2.26 ± 0.48	3.48 ± 0.37
Yellow	3.96 ± 0.22	2.82 ± 0.26	4.42 ± 0.41

Data are presented as the mean ± SD (n= 3).

Figure 3. Dose-dependent scavenging activities of the yellow, white, and blue lupin polysaccharides (ABTS^•+ radical scavenging activities are expressed in percentage with respect to the scavenging ability of Vitamin C at 0.25 mg/mL taken as 100%) (n = 3, p < 0.04)

Figure 4. Dose-dependent activities of the yellow, white, and blue lupin polysaccharides (Hydroxyl radical scavenging activities are expressed in percentage with respect to the scavenging ability of Vitamin C at a concentration of 0.532 mg/mL taken as 100%) (n = 3, p < 0.03)

Figure 5. Dose-dependent activities of the yellow, white, and blue lupin polysaccharides (Ferrous chelating activities are expressed in percentage with respect to the chelating ability of EDTA at a concentration of 0.562 mg/mL taken as 100%) (n = 3, p < 0.04)

Figure 6. Effect of YLP, WLP, and BLP on macrophage cells for TNF-α production (n = 3, p < 0.05)

Figure 7. Effect of YLP, WLP, and BLP on macrophage cells for NO production (n = 3, p < 0.04)

Figure 8. Cell viabilities of yellow, white, and blue lupin polysaccharides (n = 3, p < 0.05)

Figure 9. Prebiotic activities of BLP, WLP, and YLP (n = 3, p < 0.04). Positive control was inulin