# Functional Properties of Fruits of Common Medlar (_Mespilus germanica_ L.) Extract
## 4 Conclusions  
Our study provides valuable information on the antioxidant and antidiabetic capacity (in vitro) of medlar fruit extract and concentrated fractions at ion exchange resin. The use of a method to concentrate medlar fruit extract on an ion exchange resin resulted in a preparation with higher polyphenol concentration, antioxidant and antidiabetic activity in in vitro tests. Natural extracts of plant origin could be exploited as nutraceuticals, and cost-effective food additives for human and animal health. The biological properties of plant extracts usually cannot be attributed to the activities of single constituents. However, phenolic compounds are known to be responsible for antioxidant or antidiabetic activity, among \begin{table}
\begin{tabular}{c c c c c} \hline \hline
**No** & **Rt [min]** & **Phenolic Acids** & **Extract** & **Methanolic** & **Water** \\  & & & **(MFE)** & **Fraction (MF)** & **Fraction (WF)** \\ \hline
1 & 3.08 & Gallic acid & 8.76 \(\pm\) 1.23 b & 36.80 \(\pm\) 0.311 a & 43.84 \(\pm\) 3.27 a \\
2 & 4.08 & \(\rho\)-Aminobenzic acid & 1.17 \(\pm\) 0.42 c & 2.90 \(\pm\) 0.52 b & 4.55 \(\pm\) 1.22 a \\
3 & 4.25 & Protocatechic acid & 0.61 \(\pm\) 0.12 b & 1.166 \(\pm\) 1.02 a & 7.00 \(\pm\) 0.94 a \\
4 & 4.75 & Catechin & 0.88 \(\pm\) 0.05 b & 0.46 \(\pm\) 0.07 c & 1.21 \(\pm\) 0.25 a \\
5 & 4.84 & (\(-\))Epicatechin & 7.87 \(\pm\) 0.98 a & 0.42 \(\pm\) 0.07 c & 1.74 \(\pm\) 0.32 b \\
6 & 5.27 & Chlorogenic acid & 3.04 \(\pm\) 1.01 b & 5.28 \(\pm\) 0.92 a & 5.95 \(\pm\) 1.02 a \\
7 & 5.66 & Neochlorogenic acid & 5.27 \(\pm\) 1.24 a & 1.82 \(\pm\) 0.18 b & 1.86 \(\pm\) 0.54 b \\
8 & 6.06 & Procyanidin B2 & 3.52 \(\pm\) 0.92 a & 3.51 \(\pm\) 0.09 a & 2.93 \(\pm\) 0.36 b \\
9 & 6.85 & Caffe acid & 0.36 \(\pm\) 0.07 b & 0.33 \(\pm\) 0.11 c & 0.39 \(\pm\) 0.12 a \\
10 & 8.04 & Ferulic acid & 0.98 \(\pm\) 0.11 c & 0.48 \(\pm\) 0.07 b & 5.46 \(\pm\) 0.99 a \\
11 & 8.12 & Sinapic acid & 0.09 \(\pm\) 0.06 b & 0.35 \(\pm\) 0.06 a & \(\mathrm{nd.}\) \\
12 & & In total: & 32.05 & 64.01 & 74.93 \\ \hline \hline \end{tabular} Mean values with different letters (a–c) within the same row were statistically different (\(p<\) 0.05), the same letters form one homogeneous group. Values expressed as mean \(\pm\) standard deviation. n.d. = not determined.  
\end{table} 
Table 4: Profile of phenolic compounds quantified [mg/1 g of dry extract] in the tested extracts. \begin{table}
\begin{tabular}{c c c c} \hline \hline
**No** & **Element** & **[mg/kg]** & **[mg/Day] [61]** \\ \hline
1 & Copper & 2.68 \(\pm\) 0.41 & 0.9 \\
2 & Zinc & 6.05 \(\pm\) 0.91 & 10–15 \\
3 & Sodium & 1186.03 \(\pm\) 127.43 & 1500 \\
4 & Iron & 14.28 \(\pm\) 0.85 & 6–8 \\
5 & Magnesium & 76.3 \(\pm\) 4.06 & 250–350 \\
6 & Potassium & 585.29 \(\pm\) 37.21 & 4700 \\
7 & Calcium & 463.05 \(\pm\) 21.17 & 1000–1200 \\
8 & Manganese & 3.74 \(\pm\) 0.68 & 1.8–2.3 \\ \hline \hline \end{tabular}
\end{table} 
Table 5: Elemental composition of a purified preparation of the pulp of medlar (MF + WF) [mg/kg] and daily requirements for adults [mg/day]. other things. It is, therefore, worth using different extraction methods and procedures to increase the concentration of these compounds in the extracts (e.g., ion exchange resin purification), to achieve the best possible health-promoting effect from the obtained biological material. A concentrated medlar fruit extract with both antidiabetic and antioxidant activity may find application in the development of less expensive complementary strategies for type 2 diabetes, in combination with other nutritional and pharmacological strategies. Furthermore, consuming inhibitors of \(\alpha\)-amylase derived from natural dietary components could be an effective therapy for managing postprandial hyperglycemia with minimal side effects, as opposed to traditional treatment with drugs such as acarbose. However, it is essential to know the exact chemical composition and mechanisms of action of individual substances, in order to be able to use this plant material in therapeutic applications.