Judul: Ethnobotanical Study and the Nutritional Values of Selected Auxiliary Vegetables in Indonesia
Abstrak: Encouraging sustainable agriculture is very important to guarantee the sustainability of adequate food supply for everybody as well as to minimize environmental disruption. Indonesia has many auxiliary plants, which are beneficial to improve environmental condition, that it may increase the yield of the main crops. Many of the auxiliary plants are edible and could be consumed as vegetables as well. Unfortunately, many of the auxiliary vegetables are approaching extinction since they are incorrectly considered as useless plants or even weed. In order to conserve the auxiliary vegetables, the ethnobotanical aspects, availability, and basic nutrient information of some auxiliary vegetables in Indonesia were studied. The research revealed that the Indonesian people knowledge about the indigenous auxiliary vegetables is very poor, especially among the young generation. From 103 students majoring in agriculture, 86% of the students recognized less than 50% of the vegetables being asked. Among the 11 reviewed auxiliary vegetables, only Amaranthus spinosus (bayam duri) and Cosmos caudatus Kunth (kenikir), are commonly used as vegetables in the surveyed area (Bogor, Blitar, Jogjakarta, and Semarang). The intensity of the society's knowledge about vegetable is closely related with the availability of the plants in their area. Smaller vegetables such as as Portulaca oleracea (krokot), Marsilea crenata (semanggi), Alternanthera sessilis (bayem kramah), and Cyperus rotundus (suket teki) are less known that they could be consumed as vegetable. Due to the prevalent publications, Centella asiatica (antanan) is more famous as medicine instead of vegetable. From the nutritional analysis being conducted, Portulaca oleracea or krokot is potential to improve community health. It has 5.44 mg/100 g of B-carotene, 22.19 mg/100 g of vitamin C, and 0.19 mg/100 g of folic acid. Today's the plant is difficult to find, especially in intensively' cultivated area. Portulaca oleracea is almost never served again in Indonesian cuisine.
Keyword: auxiliary vegetable, ethnobotany, nutrition

Judul: Kajian Kandungan Senyawa Karotenoid, Antosianin dan Asam Askorbat pada Sayuran Indigenous Jawa Barat
Abstrak: Sayur-sayuran merupakan jenis makanan yang sangat dianjurkan untuk dikonsumsi dalam menu makanan. Selain mudah diperoleh dan murah harganya, sayuran juga banyak mengandung vitamin, mineral, dan komponen antioksidan seperti asam askorbat, karotenoid, flavonoid, asam-asam organik tertentu dan sebagainya. Sayuran indigenous merupakan spesies sayuran asli yang berasal dari daerah/wilayah/ekosistem tertentu, termasuk spesies pendatang dari wilayah geografis lain tetapi telah berevolusi dengan iklim dan geografis wilayah Indonesia. Sayuran indigenous di berbagai wilayah Indonesia belum banyak dimanfaatkan karena belum banyak diketahui nilai dan manfaat komponenkomponen aktif yang terkandung didalamnya. Penelitian ini dilakukan untuk mengetahui kandungan senyawa karotenoid, antosianin dan asam askorbat pada 24 jenis sayuran indigenous Jawa Barat, mengetahui hubungan antar senyawa teridentifikasi melalui metaanalisis, serta mengidentifikasi potensi sayur-sayuran tersebut melalui studi literatur berdasarkan nilai kandungan senyawa yang diperoleh dari analisis. Sayuran indigenous yang digunakan, yaitu kenikir (Cosmos caudatus H.B.K), beluntas (Pluchea indica (L.) Less.), mangkokan putih (Polyscias scutellaria (Burm.f.) Fosb.), mangkokan (Nothopanax scutellarius (Burm.f.) Merr.), daun kendondong cina (Polyscias pinnata), kecombrang (Etlingera elatior (Jack) R.M.Sm.), kemangi (Ocimum americanum L.), katuk (Sauropus androgynus (L.) Merr.), antanan (Centelia asiatica (L.) Urb.), antanan beurit (Hydrocotyle sibthorpioides Lmk.), pohpohan (Pilea melastomoides (Poir.) Bl.), daun ginseng (Talinum triangulare (Jacq.) Willd.), krokot (Portulaca oleracea L.), bunga turi (Sesbania grandiflora (L.) Pers.), kucai (Allium schoenoprasum L.), takokak (Solanum torvum Swartz), daun kelor (Moringa pterygosperma Gaertn.), daun mengkudu (Morinda citrifolia L.), lembayung (Vigna unguiculata (L.) Walp.), terubuk (Saccharum edule Hassk.), daun labu (Sechium edule (Jacq.) Swartz.), bunga pepaya (Carica papaya L.), pucuk mete (Anacardium occidentale L.) dan daun pakis (Arcypteris irregularis (C.Presl) Ching.). Analisis β-karoten dilakukan dengan menggunakan metode kromatografi (Zakaria et al., 2000), analisis asam askorbat dengan metode titrasi (Jacobs, 1951), sedangkan analisis total karotenoid dan antosianin dilakukan dengan metode spektrofotometri (Zakaria et al., 2000; Lees dan Francis, 1972). Data hasil analisis kemudian diuji statistik dengan menggunakan program Minitab 15 untuk uji PCA (Principal Component Analysis) dan program SPSS 13.0 untuk uji ANOVA (analisis ragam).
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Judul: Hamiltonian formulation for linear waves motion in two layers fluid
Abstrak: The surface wave could be considered as a wave that separates two fluids, namely water and air. Based on this assumption, it is introduced the interfacial wave, a wave between two layers of fluid with different density. The formulation of interfacial waves motion begins with deriving the base equation of irrotational ideal fluid. Furthermore, according to irrotational fluid assumption, the base equation can be stated in velocity potential. In this derivation, the fluids domain is assumed to be restricted by rigid lid boundary conditions, both at the upper and lower limit. Therefore, the interfacial waves motion can be explained in a hamiltonian formulation. In the hamiltonian formulation, total energy is defined as the sum of kinetic and potential energy. The hamiltonian system is obtained from reduction of kinetic energy by using the Dirichlet Neumann Operator. The resulted kinetic energy equation is nonlinear. Therefore, this form is linearized by first part of the Taylor expansion. This linearization gives a dispersion relation of linear wave. Based on this dispersion relation, the phase speed of the linear wave depends on the density ratio of the two layers fluid.
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