Volatile Compound Profiling of Seven Tuber Species Using HS-SPME-GC-MS and Classification by a Chemometric Approach.

Edible mushrooms are important providers of nutrients and are well recognized for their particular organoleptic properties. The volatiles that Tuber releases serve purposes beyond simply appealing to our sense of smell. Truffles have different smells and tastes due to the fact that they contain different volatile components; therefore, aroma is essential in defining the organoleptic properties and quality of truffles. In this research, seven Tuber species, namely, Tuber ferrugineum, Tuber nitidum, Tuber excavatum, Tuber rufum, Tuber puberulum, Tuber aestivum, and Tuber borchii were selected. The primary objective of this study was to carry out the first in-depth investigation of the volatile compounds and chemometric analysis of seven truffle species from the Tuber genus that are grown in Turkey. The SPME headspace combined with GC-MS analysis identified 60 volatiles from different classes, with the abundance of terpenes being followed in a decreasing order by alcohols, aldehydes, sulfides, ketones, and other aromatic compounds. According to the chemometric analysis, methional, 3-methyl-4,5-dihydrothiophene, p-(methylthio) benzaldehyde, 3-octene, linalyl acetate, methyl caproate, and ß-trans-ocimene could be highlighted as markers for T. borchii grown in Turkey. This investigation was conducted for the first time using T. ferrugineum, T. puberulum, and T. nitidum. The comparison of the volatile profile of these tubers' species displayed branded differences. Thus, the knowledge gained from this research may pave the way to identify the key aroma contributors in the chosen Tuber species.

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.

HPLC-DAD Analysis and Versatile Bioactivities of Turkish Sunflower Honeys Using Chemometric Approaches.

Sunflower honey (SH) is bright yellow, fragrant, pollen-flavoured, slightly herbaceous and has a unique taste. The present research aims to examine the enzyme inhibitory, antioxidant, anti-inflammatory, antimicrobial and anti-quorum sensing activities and phenolic compositions of 30 sunflower honeys (SHs) produced from several regions of Turkey with chemometric study. SAH from Samsun exhibited the best antioxidant activity in ß-carotene linoleic acid (IC50 : 7.33±0.17 mg/mL) and CUPRAC (A0.50 : 4.94±0.13 mg/mL) assays, anti-urease activity (60.63±0.87 %) and anti-inflammatory activity against COX-1 (73.94±1.08 %) and COX-2 (44.96±0.85 %). SHs exhibited mild antimicrobial activity against the test microorganisms while they showed high quorum sensing inhibition zones measured in the range of 42-52 mm against the CV026 strain. The phenolic composition was determined by high performance liquid chromatography with diode array detection (HPLC-DAD) system and levulinic, gallic, p-hydroxybenzoic, vanillic and p-coumaric acids were identified in all studied SHs. The classification of SHs was performed the using PCA and HCA. This study revealed that phenolic compounds and biological properties are effective in classification of SHs according to their geographical origin. The results suggest that studied SHs could be valued as potential agents with versatile bioactivities in oxidative stress-related disease, microbial infections, inflammation, melanoma, and peptic ulcer.

Chemometric classification of chestnut honeys from different regions in Turkey based on their phenolic compositions and biological activities.

The objective of this study was to investigate the phenolic composition and biological properties of chestnut honeys of 41 stations in Turkey's the Black Sea and Marmara regions. A total of sixteen phenolic compounds and organic acids were detected using HPLC-DAD and levulinic, gallic, protocatechuic, vanilic, trans-cinnamic acids and (4-hydroxyphenyl) ethanol were identified in all studied chestnut honeys. Antioxidant activities were measured by ABTS•+, ß-carotene-linoleic acid, CUPRAC, DPPH•, and metal chelating assays. Antimicrobial activities were carried out against gram positive, gram negative bacteria and Candida species using well diffusion test. Anti-inflammatory activities were evaluated against COX-1 and COX-2 whereas enzyme inhibitory activities were assessed on AChE, BChE, urease, and tyrosinase. The chemometric classification of chestnut honeys were carried out using PCA and HCA and it was seen that some phenolic compounds contributed significantly to the classification of chestnut honeys from various geographical origin.