Judul: Aktivitas Antihiperglikemik dan Antioksidan Buah Bakau Merah (Rhizophora stylosa Griff.)
Abstrak: Red mangrove (R. stylosa) is one of rhizoporaceae which has been widely used as antidiabetic drugs. One of the way how to prevent and treat diabetic is by inhibiting activity of the enzyme α-glucosidase. The purpose of this research was to determine the antihyperglycemic activity of crude extract of the red mangrove (R. stylosa) fruit. The research was performed in several steps there were characterization of mangrove fruit, extraction (maceration), proximate test (AOAC 2005), toxicity test (BSLT), antihyperglycemic test (α-glucosidase inhibition), antioxidant test (DPPH), and phytochemical test (Harborne 1987). The result showed that the methanol extract had the highest yield compared to other extracts equal to 3.45%. The methanol extract possessed the most toxic with LC50 values of 116.96 ppm. Ethyl acetate extract had the highest value of α-glucosidase inhibition (IC50) in the amount of 285.56 ppm, followed by methanol extract of 474.97 ppm, and n-hexane extract of >15000 ppm. The antioxidant test result of ethyl acetate extract showed IC50 value 79.71 ppm. Phytochemical test of ethyl acetate extract showed positive results on phenol hydroquinone, flavonoid, steroid and triterpenoid
Keyword: Bogor Agricultural University (IPB), α-glucosidase, toxicity, red mangrove, phytochemical, Antioxidant

Judul: Potensi Antioksidan, Inhibitor Tirosinase, dan Nilai Toksisitas dari Beberapa Spesies Tanaman Mangrove di Indonesia
Abstrak: Indonesia is a country rich in biodiversity. Mangrove is a plant that quite a lot in Indonesia. This research was conducted to determine potency of antioxidant, tyrosine inhibitors, and toxicity from some types of mangrove plants. The result showed that the yield of R. stylosa bark extract was 18.07% and it was the highest yield extract. S. caseolaris fruit extract had the lowest LC50 of toxicity (126.73 μg/mL). S. caseolaris bark extract had antioxidant best value with IC50 of 3.03 μg/mL. This extract also had the best potency of tyrosinase inhibitors with IC50 value of 117.67 mg/mL for monophenols and 364.99 mg/mL for diphenols. Active compounds detected in S. caseolaris extract were tannins, saponin, flavonoid, and phenol hydroquinone. S. caseolaris bark extract was the best extract due to the best ability of antioxidant activity and tyrosinase inhibitory activity.
Keyword: Bogor Agricultural University (IPB), toxicity, mangrove, inhibitors tyrosinase, best extract, antioxidant

Judul: Desain Sistem Transfer Energi Nirkabel Berbasiskan Tesla Coil
Abstrak: Tesla coil merupakan alat yang ditemukan oleh Nikola Tesla yang dapat mentransmisikan daya tanpa kabel dengan memanfaatkan prinsip induksi elektromagnetik. Pada penelitian ini dibuat sebuah prototype Tesla Coil dengan menggunakan transistor C1970 dan receiver menggunakan rangkaian LC. Identifikasi alat meliputi pengaruh daya input transmitter terhadap receiver, bentuk signal yang dipancarkan transmitter, pengaruh jarak transmitter dan receiver, nilai efisiensi serta efek alat terhadap perangkat lain. Hasil pengamatan menunjukkan bahwa semakin besar daya input maka semakin besar daya yang dipancarkan oleh transmitter. Bentuk sinyal yang dipancarkan oleh transmitter berupa gelombang listrik AC sinusoidal dengan frekuensi ~2.9 MHz. Semakin jauh jarak receiver terhadap transmitter maka semakin kecil amplitudo gelombang AC yang diterima oleh receiver, menyebabkan semakin kecil daya yang diterima oleh receiver. Adapun nilai efisiensi terbesar penangkapan daya oleh receiver yaitu sebesar 0.00516 % serta terdapat gangguan pada alat-alat tertentu seperti monitor komputer dan radio.
Keyword: rangkaian LC, receiver, tesla coil, transistor C1970, transmitter