PHENOLICS CONTENT, ANTIOXIDANT POTENTIAL, Α-Glucosidase AND Α-Amylase INHIBITORY ACTIVITIES OF FOUR FOLIAR EXTRACTS FROM PINUS SPECIES

Abstract

The current study focused on determining the contents of total phenolics (TP), flavonoids (FC), condensed tannins (CT), the flavonoid profiles, antioxidant potentials and α-glucosidase and α-amylase inhibitory capacities of the foliar extracts of Pinus engelmannii Carr., Pinus arizonica Engelm., Pinus durangensis Martínez and Pinus cembroides Zucc. Specific variations were found in TP, FC, CT, antioxidant potentials and α-glucosidase and α-amylase inhibitory activities. Pinus durangensis highlighted for its high level of FC (3.70 mg/g dry extract), high DPPH • scavenging activity, high ABTS •+ reducing potential, as well as its high inhibitory activity of α-glucosidase and α-amylase, whereas Pinus engelmannii for its high values of TP (340.15 mg/g dry extract) and CT (72.49 mg/g dry extract). Particularly, Pinus durangensis could support the development of hypoglycaemic treatments. The flavonoid profiles obtained by HPLC were species-specific, thus may be used for the development of chemical fingerprinting and quality control tools for the botanical authenticity of the bioactive extracts of these species of Pinus. RezumatStudiul a avut ca scop determinarea conținutului total de compuși fenolici (TP), flavonoide (FC), taninuri condensate (CT), profilul flavonoidelor, potențialul antioxidant și capacitatea de inhibiție a α-glucozidazei și α-amilazei ale extractelor foliare de Pinus engelmannii Carr., Pinus arizonica Engelm., Pinus durangensis Martínez și Pinus cembroides Zucc. Pinus durangensis s-a evidențiat printr-un nivel ridicat de FC (3,70 mg/g extract uscat), activitate crescută de captare a DPPH • , potențial de reducere a ABTS •+ , precum și inhibiția α-glucozidazei și α-amilazei. Pinus engelmannii s-a evidențiat prin valori ridicate ale TP (340,15 mg/g extract uscat) și CT (72,49 mg/g extract uscat). Pinus duragensis prezintă potențial în dezvoltarea unor produse hipoglicemiante. Profilurile flavonoidelor au arătat faptul că ar putea fi utilizate pentru fingerprinting chimic și în controlul calității extractelor bioactive din speciile de Pinus.

The Influence of Ecological Factors on the Phytochemical Characteristics of Pinus cembra L.

“…Moreover, the variation in the TPC in relation to altitude has also been previously studied on other species of Pinus, one study by Emrah-Dönmez et al evaluated the impact of altitude on the production of suberin in the periderm of Pinus sylvestris, reporting that the content of suberin grew proportionally with the altitude [14]. In another study, performed by Delgado-Alvarado et al on the TPC of various Pinus species, the results obtained were higher than the present findings, with the exception of rhytidome extracts collected from the highest altitude of 2429 m, which yielded comparable results to the TPC of the Pinus species assessed, despite the study reporting that Pinus cembra L. has a lower concentration of polyphenols in comparison to other species of Pinus [15]. This further proves that altitude and other particularities of climate change need to be taken into account when determining the phytocompounds in plants, especially when they play a major role in the protection of the plant against environmental stress factors.…”

“…et al tested the inhibition activity on α-glucosidase and α-amylase of a series of Pinus species: Pinus engelmannii, Pinus arizonica, Pinus durangensis, and Pinus cembroides. It was found that all foliar extracts analyzed were more active on αglucosidase inhibition than acarbose (an antidiabetic drug), but less active than acarbose on inhibiting α-amylase, underlining the fact that there is an important antidiabetic potential in Pinus species [15].…”