Name: Mirieli Bernardes Xavier
Type: MSc dissertation
Publication date: 20/12/2017
Advisor:
Name |
Role |
|---|---|
| Maria do Carmo Pimentel Batitucci | Advisor * |
Examining board:
| Name |
Role |
|---|---|
| Claudia Masrouah Jamal | External Examiner * |
| Geralda Gillian Silva Sena | External Alternate * |
| Jose Aires Ventura (M/D) | Internal Examiner * |
| Maria do Carmo Pimentel Batitucci | Advisor * |
| Valéria de Oliveira Fernandes | Internal Alternate * |
Summary: ABSTRACT
Coffee is the second most consumed beverage in the world and has Brazil as the main producer and exporter worldwide. Espírito Santo is the second largest producer of coffee in the country and much of its economy is focused on the trade of this fruit. Arabica coffee is the one with the highest commercial value and therefore, it is the most exported species today. In addition to its commercial validity, coffee is also known to have pharmacological properties, which are reinforced by the presence of phytochemical constituents with antioxidant activity. Based on this, the present study evaluated the ethanolic extracts of two arabica coffee cultivars, "Catuaí vermelho IAC 99" and "Catucaí amarelo 2SL", at different levels of post-harvest processing in order to quantify Trigonelina and Chlorogenic acid by HPLC ; to verify the content of total tannins and flavonoids by colorimetric test; to analyze the antiproliferative activity by the MTT method, with healthy cells (human lymphocytes) and tumor cells (Sarcoma 180), and to evaluate the antioxidant activity of the extracts by means of four different methods: ABTS · +, DPPH and FRAP and chelating activity of iron (Fe2 +), in order to identify the extract with better performance, in order to guide the best condition for consumption and to demonstrate the possible influences of its processing on its phytochemical characteristics. The results suggest that the yellow Catucaí amarelo 2SL (CASP) sample had the best antioxidant activity among all the samples evaluated, but in general, the dry and pilated samples showed the best performance, suggesting that it is the best coffee refers to the maximum use of its bioactive compounds. In the case of these samples, the compound most correlated with the antioxidant activity was the tannin, however, it is not possible to discard the action of the other compounds evaluated here. The roasting processes were detrimental to the quality of the beverage, regarding the availability of
compounds bioactive, the two roasting levels determined successive losses of bioactive compounds and, consequently, of the antioxidant activity, not corroborating with many studies showing the increase of this activity after a soft roast. The MTT tests on healthy cells indicated that the samples served as mitogens for all samples. However, the Catuaí immature cherry red (CVCI) sample obtained the highest percentage of proliferative activity, and it was not possible to attest to this effect. Tumor cells showed a positive response to cell death, but it can not be confirmed that coffee (at least those tested here) are effective in killing tumor cells, an assay in different lineages is necessary.
Keywords: Arabica coffee CLAE antioxidant antiproliferative activity
