Perkembangan bulbus dan daun bawang Dayak (Eleutherine americana Merr.) serta kandungan senyawa bioaktif turunan naftokuinon

KUNTORINI, Evi Mintowati, Prof. Dr. Issirep Sumardi

2008 | Tesis | S2 Biologi

Bawang dayak (Eleutherine americana Merr.) merupakan salah satu tanaman yang berkhasiat obat mengandung senyawa golongan naftokuinon. Senyawa naftokuinon telah diketahui bersifat sangat toksik, umumnya digunakan sebagai antimikrobia, antifungal, antiviral dan antiparasit, tersimpan dalam vakuola sel. Penelitian ini bertujuan menganalisis struktur perkembangan bulbus dan daun bawang dayak serta kandungan senyawa bioaktif turunan naftokuinon. Penanaman umbi bawang dayak dengan media tanah dilakukan di rumah kaca dan lahan terbuka. Pengamatan dilakukan sebanyak 6 kali dengan interval waktu tiap pengamatan dua minggu (P1 hingga P6) untuk tanaman di rumah kaca, sedangkan pengamatan tanaman di lahan terbuka hanya P2 (minggu ke 4) dan P6 (minggu ke 12). Hasil pengamatan tanaman di lahan terbuka dibandingkan dengan tanaman di rumah kaca pada P2 dan P6.Parameter yang diamati berupa diameter umbi, panjang umbi, jumlah daun, tebal lapisan epidermis daun, jumlah somata daun per mm2, tebal mesofil dan kandungan senyawa bioaktif turunan naftokuinon daun dan umbi. Tebal lapisan epidermis, dan tebal mesofil diamati dengan pembuatan preparat metode parafin pewarnaan tunggal, jumlah stomata diamati dengan pembuatan preparat metode leaf clearing. Kandungan senyawa turunan naftokuinon dianalisis dengan Kromatografi Cair Kinerja Tinggi (KCKT). Data kuantitatif dianalisis dengan ANAVA dan dilanjutkan dengan uji Duncan Multiple Range Test (DMRT) pada taraf uji 5 %. Hasil penelitian di rumah kaca dan lahan terbuka menunjukkan adanya peningkatan secara signifikan pada diameter dan panjang umbi, tebal mesofil daun, tebal lapisan epidermis atas dan bawah selama perkembangan. Jumlah stomata permukaan atas lebih sedikit dibandingkan dengan permukaan bawah. Ada peningkatan ukuran pada sel-sel parenkim umbi. Berkas pengangkut umbi selain ukurannya meningkat juga mengalami penambahan unsur-unsur floem dan xilem. Senyawa bioaktif turunan naftokuinon telah terbentuk pada daun dan umbi saat pengamatan pertama (minggu ke 2). Kandungan bioaktif pada umbi meningkat secara signifikan dengan meningkatnya ukuran sel-sel penyusun jaringan parenkim pada tanaman yang ditumbuhkan di rumah kaca dan lahan terbuka. Pada daun kandungan senyawa bioaktif tidak berbeda nyata selama perkembangan meskipun ada peningkatan ukuran tebal mesofil dan sel-sel penyusunnya sebagai tempat sintesis. Kandungan senyawa bioaktif pada umbi lebih besar dibandingkan pada daun pada minggu ke-2 dan akhir waktu pengamatan (minggu ke-12).

Red Bulb plant (Eleutherine americana Merr.) is commonly used as a traditional medicine because it contains bioactive naphtoquinon-derivatives. Naphtoquinones are very toxic, and usually used as antimicrobial, antifungal, antiviral and antiparasitic agents. They are deposited in cell vacuoles. This present study was aimed to investigate the anatomical structure of bulb and leaf of red bulb plants during their development and their naphtoquinon derivative contents. Red bulb plants were grown on soil in a greenhouse and in the open field. The development were assesed six times (P1 – P6) in a two week interval. Plants grown in the field were assesed twice at fourth week and twelfth (P2 & P6). The parameters examined were the diameter and length of bulbs, leaf number, thickness of epidermis layer and mesophyll tissue, number of stomata and naphtoquinon-derivative contents. The thicknes of epidermis layer and mesofil tissue were analyzed by preparing slides using paraffin embedding method. The number of stomata was determined using leaf clearing method. Naphtoquinon derivative contents were analyzed using HPLC. Significant differences were determined by Anova followed by Duncan Multiple Range Test (DMRT) with 5% significance level. During plant development, a significant increase was observed in the diameter and the length of bulbs as well as in the thickness of mesophyll and epidermis layers. Fewer stomata were found on the dorsal than the ventral surface of the leaves. The size parenchymal cells increased. In addition to an increasing of the size of vascular bundles, more phloem and xylem components were also observed. The naphtoquinon content could be detected in leaves and bulbs since the first observation (second week). The content of bioactive compounds in bulbs increased significantly as the size of parenchymal cells increased for both plants grown in the green house and open field plants. No significant difference in the content of bioactive compounds of leaves was found during development, despite the rise in the thickness of mesophyll and the constituting cells as the location of synthesis. The bioactive content of bulbs were higher than that of leaves both in the beginning (second week) and the end of the experiment (twelfth week).

Kata Kunci : Bulbus,Daun bawang Dayak,Eleutherine americana,Naftokuinon, Development, bulbus, leaf, Eleutherine americana, Naphtoquonone