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All Journal Biology, Medicine, & Natural Product Chemistry Bioscientist : Jurnal Ilmiah Biologi
Tunjungsari, Gerda Pintoko
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Agriculture, Biological Sciences & Forestry Biochemistry, Genetics & Molecular Biology Education Immunology & microbiology Medicine & Pharmacology Public Health Social Sciences

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Comparison of Antioxidant Activity and Chemical Profile between Green Tea Kombucha with Green Tea and Rosela Combination Kombucha Tunjungsari, Gerda Pintoko; Fikroh, Retno Aliyatul
Bioscientist : Jurnal Ilmiah Biologi Vol. 12 No. 1 (2024): June
Publisher : Department of Biology Education, FSTT, Mandalika University of Education, Indonesia.

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.33394/bioscientist.v12i1.9977

Abstract

This study investigates the antioxidant potential and chemical profile of kombucha made from green tea leaves and roselle flowers, analyzing pH, alcohol content, and the impact of fermentation time. Kombucha was prepared with green tea and a 1:1 mixture of green tea and roselle, with samples analyzed on days 1, 4, 8, 12, 16, and 24. Antioxidant activity, pH, and alcohol content were measured, and statistical analyses including one-way ANOVA, Tukey HSD, and Spearman correlation tests were conducted. Results indicated that the combination kombucha exhibited higher antioxidant activity (96.39% DPPH inhibition) compared to green tea kombucha (79.62%). There was no significant difference in pH and alcohol content between the two types (p > 0.05). A strong negative correlation was found between pH and fermentation time (-0.589, p < 0.001) and pH and alcohol content (-0.571, p < 0.001), while a strong positive correlation was observed between % inhibition and fermentation time (0.637, p < 0.001). The findings suggest that combining green tea and roselle enhances antioxidant activity in kombucha, and fermentation time significantly affects antioxidant activity, pH, and alcohol content.
Phytochemical Profile, Antioxidant Activity, and Brine Shrimp Lethality Test of Thyrsostachys siamensis (Siamese Bamboo) Leaf Extracts Hidayah, Muhamad Aditya; Ayudia, Indah; Tunjungsari, Gerda Pintoko; Fikroh, Retno Aliyatul; Ahmad, Alfandi
Biology, Medicine, & Natural Product Chemistry Vol 15, No 1 (2026)
Publisher : Sunan Kalijaga State Islamic University & Society for Indonesian Biodiversity

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.14421/biomedich.2026.151.379-389

Abstract

Cancer and oxidative-stress–related disorders continue to rise globally, driving interest in plant-based antioxidants with concurrent cytotoxic potential. This study aimed to characterize the phytochemical profile, antioxidant activity, and brine shrimp (Artemia salina) lethality of Thyrsostachys siamensis (Siamese bamboo) leaf extracts obtained with solvents of increasing polarity (n-hexane, chloroform, acetone, ethyl acetate, methanol, ethanol, and water). Ethanol appears as the most effective solvent for T. siamensis, combining a solid extraction yield (7.78%) with the richest phytochemical profile (positive for alkaloids, flavonoids, saponins, tannins, and phenolics). This broad chemical recovery corresponds to the strongest bioactivity, shown by its lowest IC50 (91.48 ± 0.12 µg/mL) and LC50 (80.78 ± 0.62 µg/mL). Acetone (6.42%) and ethyl acetate (5.11%) offer moderate yields and selective enrichment of semi-polar constituents, reflected in intermediate IC50 values (144–150 µg/mL) and LC50 values (273–350 µg/mL). In contrast, hexane despite providing the highest mass recovery (11.34%) contains mainly non-phenolic components and shows weak biological activity (IC50 200.52 ± 0.38 µg/mL, LC50 620.06 ± 0.76 µg/mL). Chloroform, with limited phytochemical content, yields the poorest performance (IC50 238.30 ± 1.56 µg/mL, LC50 926.40 ± 4.27 µg/mL).
Co-Authors Ahmad, Alfandi Ayudia, Indah Fikroh, Retno Aliyatul Hidayah, Muhamad Aditya