Antioxidant and lipase inhibitory activities of Camellia pollen extracts: the effect of composition and extraction solvents

Figures & data

Table 1. The biocompound content of the Camellia pollen extracts.

	Flavonoids	Phenolics	Protein	Reducing sugar	Flavonids	Phenolics	Protein	Reducing sugar
Pollen extract	(mg RE/g)*	(mg GAE/g)*	(mg casein/g)*	(mg G/g)*	(mg RE/g)**	(mg GAE/g)**	(mg casein/g)**	(mg G/g)**
Methanol	4.19 ± 0.20b	15.98 ± 0.66a	571.05 ± 4.91a	319.41 ± 5.18b	7.14 ± 0.34	3.26 ± 0.14	939 ± 63	545.05 ± 8.85
Ethanol	5.62 ± 0.28a	10.29 ± 0.66b	258.79 ± 2.50c	181.69 ± 3.27c	18.80 ± 0.93	4.11 ± 0.26	866 ± 30	607.82 ± 10.92
Acetone	3.80 ± 0.27bc	0.76 ± 0.04e	25.44 ± 0.34e	8.53 ± 0.31e	153.80 ± 10.81	3.69 ± 0.19	1029 ± 16	345.02 ± 12.40
N-butyl alcohol	3.85 ± 1.12bc	1.90 ± 0.07d	66.64 ± 3.48d	31.75 ± 0.79d	41.37 ± 12.78	2.44 ± 0.09	716 ± 37	341.14 ± 8.45
Ethyl acetate	2.82 ± 0.81c	0.47 ± 0.01e	15.36 ± 1.47e	2.57 ± 0.62f	44.17 ± 12.64	0.87 ± 0.03	240 ± 23	40.09 ± 9.72
Petroleum ether	0.26 ± 0.07e	0.30 ± 0.00e	9.66 ± 0.34e	0.61 ± 0.05f	5.35 ± 6.57	0.73 ± 0.01	195 ± 07	12.34 ± 1.06
Water	0.44 ± 0.01d	9.08 ± 0.40c	495.60 ± 1.00b	343.36 ± 1.91a	0.77 ± 0.03	1.90 ± 0.08	828 ± 71	602.25 ± 3.35

Notes: mean ± standard deviation (n = 3); mg/g means mg standard per gram sample. Within the column, means followed by different letters are significantly different (p < 0.05). *Calculations are based on dry pollen. **Calculations are based on pollen extract.

Figure 1. ABTS radical-scavenging ability of the Camellia pollen extracts.

Table 2. Lipase inhibitory ability and antioxidant activity of the Camellia pollen extracts.

Pollen extract	Lipase inhibition	ABTS	DPPH	FRAP^b
Methanol	43.011 ± 0.905^a	2.554 ± 0.341	5.607 ± 0.122	10.651 ± 0.025
Ethyl acetate	2.071 ± 0.200	5.158 ± 0.236	–	0.900 ± 0.119
Ethanol	24.562 ± 0.938	2.869 ± 0.228	2.920 ± 0.04	6.739 ± 0.396
Acetone	1.191 ± 0.073	7.060 ± 0.170	3.086 ± 0.122	3.322 ± 0.048
N-butyl alcohol	–	4.187 ± 0.063	5.024 ± 0.764	3.766 ± 0.188
Petroleum ether	–	–		2.986 ± 0.052
Water	78.092 ± 9.283	2.617 ± 0.047	30.525 ± 2.685	6.223 ± 0.383
Orlistat	0.046 ± 0.003 (µg/mL)	Vc (0.042 ± 0.000) (mg/mL)	Vc (140.30 ± 3.78) (µg/mL)	Vc (0.067 ± 0.002) (mg/mL)

Note: IC₅₀ is defined as the concentration of extract required to inhibit 50% of the enzyme activity. It was obtained by the least-square regression analysis of the plot of the sample concentrations versus the percentages of lipase activity.

^a Values are expressed as mean ± standard deviation of three replicates. Within the column, means followed by different letters are significantly different (p < 0.05).

^b FRAP value is defined as the concentration of extracts which Abs ₅₉₅= 0.1 (1.09 mmol/L FeSO₄).

Figure 2. FRAP values of the Camellia pollen extracts. (A) FRAP values of methanol, ethanol, N-butyl alcohol, and water extracts. (B) FRAP values of acetone, ethyl acetate, and petroleum ether extracts.

Figure 3. DPPH radical-scavenging ability of the Camellia pollen extracts. (A) DPPH radical-scavenging ability of Methanol, ethanol, N-butyl alcohol, and water extracts. (B) DPPH radical-scavenging ability of acetone, ethyl acetate, and petroleum ether extracts.

Figure 4. Lipase inhibitory activity of the Camellia pollen extracts. (A) Lipase inhibitory activity of the Methanol, ethanol, and water extracts. (B) Lipase inhibitory activity of Acetone, N-butyl alcohol, ethyl acetate, and petroleum ether extracts.

Table 3. The correlation coefficient between the components’ content of pollen extracts and the antioxidant activity.

	Phenolics	Flavonids	Reducing sugar	Protein
	(mg GAE·g^−1)	(mg RE·g^−1)	(mg G·g^−1)	(mg casein·g^−1)
DPPH radical scavenging (IC50 mg·mL^−1)	0.243^ns	−0.869*	−0.289^ns	0.544^ns
ABTS radical scavenging (IC50 mg·mL^−1)	−0.777	0.182^ns	−0.518^ns	−0.829*
FRAP value	0.963^ns	0.312^ns	0.871*	0.905^ns

Note: ^ns represents not significant (P > 0.05), * represents significant (p < 0.05), ** represents highly significant (p < 0.01).

Table 4. The correlation coefficient between the components’ content of pollen extracts and the lipase inhibitory activity.

	Phenolic	Flavonid	Reducing sugar	Protein
	(mg GAE·g^−1)	(mg RE·g^−1)	(mg G·g^−1)	(mg casein·g^−1)
Lipase inhibition (IC50 mg·mL^−1)	0.772^ns	−0.296^ns	0.330^ns	0.877^ns

Note: ^ns represents not significant (p > 0.05).

Table 5. Oil content and fatty acid content of Camellia pollen extracts.

			Fatty acid content (%)
Pollen extract	Extraction rate (%)	Oil content (%)	Oleic acid	Linoleic acid	Linolenic acid	Stearic acid
Methanol	49.05	0.92	30.39	5.82	57.98	1.27
Ethyl acetate	5.36	3.60	31.95	4.12	49.02	2.06

Data availability statement

The data that support the findings of this study are openly available in the Figshare repository at https://doi.org/10.6084/m9.figshare.20544090.v1 and https://doi.org/10.6084/m9.figshare.20218853.v3.