Assessment of in vitro cytotoxicity, anti-Alzheimer, and antidiabetic properties of fenugreek, white mulberry, and nettle leaves

Year 2025, Volume: 29 Issue: 1, 132 - 144

Kubra Feyza Erol , Gözde Kutlu

https://doi.org/10.29050/harranziraat.1530273

Abstract

Leafy plants are known for their rich bioactive profiles and have gained attention for their potential health benefits. This study evaluated the total phenolic content (TPC) using the Folin-Ciocalteu method and antioxidant properties, including ferric reducing antioxidant power (FRAP) and 2,2'-azinobis-(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) activities, of ethanolic extracts from fenugreek (FL), white mulberry (WBL), and nettle leaves (NL). It also investigated their inhibitory effects on alpha-amylase, alpha-glucosidase, acetylcholinesterase, and butyrylcholinesterase, and assessed their cytotoxicity on human embryonic kidney cells (HEK-293) and colorectal adenocarcinoma cells (CaCo-2) using MTT assays. The results revealed that the TPC was highest in NL (241.86 mg gallic acid equivalents (GAE) g-1 dry weight (DW)), followed by WBL (165.68 mg GAE g-1 DW) and FL (72.09 mg GAE g-1 DW), with NL also showing the highest FRAP (240.48 μmol Fe²⁺ g-1 extract) and ABTS antioxidant activities (19.26 mg trolox equivalents (TE) g-1 extract). Moreover, the inhibition of alpha-amylase ranged from 8.85% to 90.39% depending on the extract concentration (62.5–500 µg mL-1), with WBL and NL showing significant inhibitory effects on alpha-glucosidase within the same concentration range. Additionally, NL ethanolic extracts exhibited the highest butyrylcholinesterase inhibitory activity at 38.40% compared to FL (33.87%) and WBL (17.94%) at 2 mg mL-1, while acetylcholinesterase inhibition rates ranged from 23.14% for WBL to 53.35% for NL across all leaf samples. Furthermore, the ethanol extracts from FL, WBL, and NL yielded IC50 values of 1159.98, 1235.67, and 972.22 µg mL-1, respectively, on HEK-293 cells, while on CaCo-2 cells, the IC50 values were 897.41 µg mL-1 for FL, 754.11 µg mL-1 for WBL, and 648.80 µg mL-1 for NL. These findings underscore the potential of NL, FL, and WBL as valuable natural sources with diverse health benefits and significant therapeutic potential, making them promising candidates for industrial applications as functional ingredients.

Keywords

Fenugreek leaves, mulberry leaves, nettle leaves, cytotoxic activity, enzyme inhibition activity

Çemen otu, beyaz dut ve ısırgan otu yapraklarının in vitro sitotoksik, anti-Alzheimer ve antidiabetik özelliklerinin değerlendirilmesi

Abstract

Yapraklı bitkiler, zengin biyoaktif bileşenler barındırmalarıyla dikkat çeker ve bu bileşiklerin sağlık üzerindeki olumlu etkileri, son yıllarda giderek artan bir ilgiyle araştırılmalarına yol açmıştır. Bu çalışma, çemen otu (FL), beyaz dut (WBL) ve ısırgan otu yapraklarının (NL) etanol ekstraktlarının toplam fenolik içeriğini (TPC) ve demir indirgeme antioksidan gücü (FRAP) ile 2,2′azinobis-(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) serbest radikali giderme aktivitelerini içeren antioksidan özelliklerini değerlendirmiştir. Ayrıca, bu ekstraktların alfa-amilaz, alfa-glukozidaz, asetilkolinesteraz ve bütirilkolinesteraz üzerindeki inhibe edici etkileri de araştırılmış ve insan embriyonik böbrek hücreleri (HEK-293) ve kolorektal adenokarsinom (Caco-2) hücre hatlarındaki sitotoksisiteleri değerlendirilmiştir. Sonuçlar, TPC'nin NL'de (241.86 mg GAE g⁻¹ DW) en yüksek olduğunu, bunu WBL (165.68 mg GAE g⁻¹ DW) ve FL'nin (72.09 mg GAE g⁻¹ DW) takip ettiğini ortaya koymuştur. NL ayrıca WBL ve FL'ye kıyasla en yüksek FRAP (240.48 μmol Fe²⁺ g⁻¹ ekstrakt) ve ABTS antioksidan aktivitelerini (19.26 mg TE g⁻¹ ekstrakt) göstermiştir. Ayrıca, alfa-amilaz inhibisyonu, ekstrakt konsantrasyonuna (62.5–500 µg mL⁻¹) bağlı olarak %8.85 ile %90.39 arasında değişmiş, WBL ve NL aynı konsantrasyon aralığında alfa-glukozidaz üzerinde önemli inhibe edici etkiler göstermiştir. NL etanol ekstraktları, 2 mg mL⁻¹ konsantrasyonda FL (%33.87) ve WBL (%17.94) ile karşılaştırıldığında en yüksek bütirilkolinesteraz inhibisyon aktivitesini (%38.40) sergilemiştir. Asetilkolinesteraz inhibisyon oranları ise %23.14 (WBL) - %53.35 (NL) arasında değişmiştir. Ayrıca, FL, WBL ve NL'nin etanol ekstraktlarının IC50 değerleri HEK-293 hücrelerinde sırasıyla 1159.98 µg mL-1, 1235.67 µg mL-1 ve 972.22 µg mL-1 iken, Caco-2 hücrelerinde IC50 değerleri FL için 897.41 µg mL-1, WBL için 754.11 µg mL-1 ve NL için 648.80 µg mL-1 olarak hesaplanmıştır. Bu bulgular, FL, NL ve WBL’nin hem potansiyel sağlık faydalarını hem de dikkate değer terapötik potansiyelini vurgulayarak onları endüstriyel uygulamalar için fonksiyonel bileşen olarak değerlendirilebilecek umut verici doğal kaynaklar haline getirmektedir.

Keywords

Çemenotu Yaprakları, Dut Yaprakları, Isırgan Otu Yaprakları, Sitotoksik Aktivite, Enzim İnhibitör Aktivitesi

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