Study on Phenolic and Organic Acid Compositions and Antioxidant and Enzyme Inhibition Activities of Agaricomycetes Mushroom Species from Turkey.

Mushrooms stand out as one of nature's best gifts among the natural product sources with their diversity, therapeutic values and increasing popularity. In this study, antioxidant (ABTS·+ scavenging, ß-carotene-bleaching, cupric-reducing antioxidant capacity (CUPRAC), DPPH· scavenging, and metal chelating assays), and enzyme (buty-rylcholinesterase (BChE) and acetylcholinesterase (AChE), α-amylase and α-glucosidase) inhibition activities of the extracts obtained from Coprinus comatus (O.F. Müll.) Pers., Cerrena unicolor (Bull.) Murrill, Inocutis rheades (Pers.) Fiasson & Niemela and Leptoporus mollis (Pers.) Quél. mushroom species were investigated. The presence of phenolic and organic acid compounds associated with the bioactive properties of the mushroom species was determined by HPLC-DAD. Fumaric acid was found to be prominent compound in C. comatus (43.90 µg/g dw) and C. unicolor (659.9 µg/g dw), vanillin in L. mollis (19.48 µg/g dw), and p-coumaric acid in I. rheades (21.32 µg/g dw). L. mollis methanol extract, as well as higher antioxidant activity than the standards in CUPRAC and ß-carotene-bleaching assays, was noted as superior antioxidant active in all assays (except metal chelating). C. comatus possessed the highest inhibition activity on α-amylase (IC50: 0.23 mg/mL for methanol extract), AChE (IC50: 125.50 µg/mL for hexane extract), and BChE (IC50: 61.03 µg/mL for methanol extract). Also, C. comatus methanol (IC50: 0.09 mg/mL) and L. mollis hexane (IC50 : 0.11 mg/ mL) extracts were better α-glucosidase inhibition active than the acarbose (IC50: 0.37 mg/mL). Our study ascertained that the studied mushroom species are particularly sources of biochemically active compounds with therapeutic potential.

Citrus Honeys from Three Different Regions of Turkey: HPLC-DAD Profiling and in Vitro Enzyme Inhibition, Antioxidant, Anti-Inflammatory and Antimicrobial Properties with Chemometric Study.

The objectives of the present study are to compare the phenolic profiles and biological activities of 15 citrus honey samples from three different locations in Turkey using a chemometric approach. The HPLC-DAD analysis was used to determine phenolic profiles. Nineteen phenolic compounds were identified. Gallic acid (107.14-717.04 µg/g) was recorded as the predominant compound. AF (Antalya-Finike) had the highest antioxidant activity in ABTS⋅+ (IC50 : 18.01±0.69 mg/mL), metal chelating (IC50 : 6.20±0.19 mg/mL) and CUPRAC (A0.50 : 12.05±0.68 mg/mL) assays, while it revealed the best anti-inflammatory activity against COX-2 (17.28±0.22 %) and COX-1 (43.28±0.91 %). AM (Antalya-Manavgat) was the most active in ß-carotene-linoleic acid (IC50 : 10.05±0.19 mg/mL), anti-urease (38.90±0.69 %), anti-quorum sensing and antimicrobial activities. AKO1 (Adana-Kozan-1) in DPPH⋅ (IC50 : 34.25±0.81 mg/mL) assay, AKU1 (Antalya-Kumluca-1) in tyrosinase inhibition activity (37.73±0.38 %) assay, AKU2 (Antalya-Kumluca-2) in AChE (10.55±0.63 %) and BChE (9.18±0.45 %) inhibition activity assays showed the best activity. Chemometric tools were applied to the phenolic compositions and biological properties. PCA and HCA ensured that 15 citrus honey samples were grouped into 3 clusters. The results showed that myricetin, kaempferol, vanillin, protocatechuic acid, rosmarinic acid, rutin, vanillic acid, gallic acid, catechin and p-hydroxyphenyl acetic acid are phenolic compounds that can be used in the classification of citrus honeys.

Chemical Profile, In Vitro Enzyme Inhibitory, and Antioxidant Properties of Stereum Species (Agaricomycetes) from Turkey.

Recently, mushroom species have been the focus of researchers' interest because of several bioactivities. The aim of this study was to investigate the chemical profile and biological activities of various extracts of two Stereum species (S. rugosum and S. sanguinolentum). Antioxidant activity was tested using ß-carotene-linoleic acid, DPPH scavenging, ABTS·+ scavenging, cupric-reducing antioxidant capacity (CUPRAC), and metal chelating assays. The extracts were also tested for their enzyme inhibitory activities against acetylcholinesterase (AChE) and butyrylcholinesterase (BChE). HPLC-DAD was applied for the analysis of phenolic compounds, and fatty acid compositions were determined using GC and GC-MS. When fumaric acid and catechin hydrate were found as the most abundant phenolic compounds in both Stereum species, oleic acid and palmitic acid were identified as major fatty acids. Both of the studied Stereum methanol extracts were determined as the most active in ß-carotene-linoleic acid, DPPR, ABTS·+, and CUPRAC assays; the n-hexane extracts were found to be most active in metal chelating and AChE inhibitory activity assays. In addition, the methanol extract of S. sanguinolentum (IC50: 34.26 ± 0.31 µg/mL) showed higher ABTS·+ scavenging activity than α-tocopherol (IC50: 38.51 ± 0.54 µg/mL). The acetone extracts were found as potent inhibitors against BChE. These results suggest that Stereum species could be an antioxidant source and cholinesterase agent in pharmaceutic, food, and cosmetics industries.