Effects of Different Drying Methods and Solvents on Biological Activities of Curcuma aeruginosa Leaves Extract

Abstract

Curcuma aeruginosa Roxb. is one of the plants from the Zingiberaceae family which the rhizome has been used for medicinal purposes. However, the biological properties of the leaves have not been fully explored. Therefore, this study was conducted to evaluate the effects of different drying methods and solvents on total phenolic content, antioxidant and anti-hyperglycemic activities of C. aeruginosa leaf extract. Samples were dried by oven drying (OD) and freeze drying (FD), and then extracted using different ratios of ethanol:water (100:0, 50:50 and 0:100). The amount of phenolic content (TPC) was determined using a spectrophotometer. Antioxidant activity was tested using the Free Radical Scavenging (DPPH) test and the Ferric Reducing Antioxidant Power assay (FRAP), while the anti-hyperglycemic test was evaluated by determining the percentage of α-glucosidase inhibition. The results showed that FD at 100:0 and 50:50 concentrations had the highest phenolic content (30.88 and 33.06 mg GAE/g extract, respectively) and highest antioxidant activity value (38.24 and 42.46 mg TEAC/g extract, respectively). For DPPH, FD at 50:50 showed the highest inhibition of 71.48% compared to other extracts. Whereas FD at 100:0, 50:50 and 0:100 showed the highest α-glucosidase inhibition of 25.65, 30.78 and 27.65%, respectively. However, compared to Quercetin, the extract showed mild anti-hyperglycemic activity. The results indicated that FD is the best method of drying while 50:50 showed as the best solvents. Positive correlation between TPC with antioxidant and anti-hyperglycemic activities showed that C. aeruginosa leaf has potential as a source of natural antioxidant with the presence of phenolic compounds.

Diversity of Volatile Compounds in Ten Varieties of Zingiberaceae

“…The rhizome of C. aeruginosa has been used as a traditional medicine for gastrointestinal issues such as diarrhea and colic, as well as for uterine involution, uterine pain, and inflammation [48]. C. attenuata has shown medicinal value, and most Curcuma species have been used as good natural anti-oxidants in functional foods, medicines, and cosmetics [49,50].…”

Kandungan Senyawa Polifenol dan Aktivitas Antioksidan Daun Tumbuhan Apu-apu (Pistia stratiotes) dengan Metode Pengeringan yang Berbeda

“…Keywords: antioxidants, bioactive compounds, drying temperature, Pistia stratiotes suhu pengeringan dapat memengaruhi kandungan senyawa bioaktif dan aktivitas antioksidan ekstrak daun Curcuma aeruginosa (Nasir et al, 2021) dan Zingiber officinale (Gümüşay et al, 2015) sehingga penulis berhipotesis bahwa perbedaan metode pengeringan juga dapat memberikan pengaruh terhadap kandungan senyawa polifenol dan antioksidan pada ekstrak daun tumbuhan apu-apu. Penelitian ini bertujuan mengekstrak senyawa polifenol dari daun tumbuhan apu-apu yang dikeringkan dengan metode pengeringan yang berbeda dan mengukur aktivitas antioksidan senyawa tersebut.…”

“…Hasil ini sesuai dengan penelitian sebelumnya melaporkan bahwa pengeringan beku daun temu hitam (Curcuma aeruginosa) menghasilkan kadar polifenol yang lebih tinggi (33,06 mg GAE/g sampel kering) jika dibandingkan dengan pengeringan dengan oven pada suhu 40ºC yaitu 26,70 mg GAE/g sampel kering (Nasir et al, 2021). Hasil penelitian lainnya juga melaporkan bahwa daun S. androgynus yang dikeringkan dengan metode pengeringan matahari memiliki kandungan senyawa polifenol yang lebih rendah jika dibandingkan dengan pengeringan Gambar 2 Total polifenol (a) dan kadar flavonoid (b) ekstrak daun apu-apu yang dikeringkan dengan metode yang berbeda; matahari; oven; freeze drying.…”