Extracts prepared from floral meristematic tissue of alfalfa (Medicago sativa L.) were investigated for expression of the enzyme transglutaminase in order to identify the major protein substrate for transglutaminase-directed modifications among plant proteins. The large polymorphic subunits of ribulose 1,5-bisphosphate carboxylase/oxygenase in alfalfa, with molecular weights of 52,700 and 57,600, are major substrates for transglutaminase in these extracts. This was established by: (a) covalent conjugation of monodansylcadaverine to the large subunit followed by fluorescent detection in SDS-polyacrylamide gels; (b) covalent conjugation of [14C]putrescine to the large subunit with detection by autoradiography; (c) covalent conjugation of monodansylcadaverine to the large subunit and demonstration of immunocross-reactivity on nitrocellulose transblot of the modified large subunit with antibody prepared in rabbits against dansylated-ovalbumin; (d) demonstration of a direct dependence of the rate of transglutaminase-mediated, [14C]putrescine incorporation upon the concentration of ribulose, 1,5-bisphosphate carboxylase/oxygenase from alfalfa or spinach; and (e) presumptive evidence from size exclusion chromatography that transglutaminase may cofractionate with native molecules of ribulose 1,5-bisphosphate carboxylase/oxygenase in crude extracts. Analysis of the primary structure of plant large subunit has revealed numerous potential glutaminyl and lysyl sites for transglutaminasedirected modifications of ribulose 1,5-bisphosphate carboxylase/ oxygenase.

In this research, antioxidant activity, total phenolic, and flavonoid content of n-hexane, ethyl acetate, and methanol fractions of roots, stem bark, and leaves of Elaeocarpus mastersii King were determined by the colorimetric method using DPPH assay (1,1-diphenyl-2-picrylhydrazyl), Folin-Ciocalteu reagent, and aluminum chloride reagent, respectively. Phytochemical screening was evaluated by specific reaction of constituents to the specific reagent. Ethyl acetate fraction had the best value of phenolic content and antioxidant activity among all fractions which the best value was obtained from the leaves (380.99 ± 2.14 mg GAE/g DW and IC50 1.95 ± 0.01 µg/mL) followed by the roots (362.88 ± 1.89 mg GAE/g DW and IC50 2.05 ± 0.01 µg/mL) and the stem bark (341.89 ± 3.97 mg GAE/g DW and IC50 2.36 ± 0.02 µg/mL). All fractions of this plant showed the low value of flavonoid content. The phytochemical screening exhibited that this plant was dominated by phenolic and alkaloid compounds. These results demonstrate the great potential of Elaeocarpus mastersii King as a natural antioxidant and active compounds.

Agricultural and agro-industrial wastes, which are mostly in the form of lignocelluloses, basically have no economic value may be even be considered of negative value because they still need further treatment. Lignocelluloses consist of hemicelluloses, celluloses, and lignin. Celluloses are the biggest component and can be transformed into energy sources, paper, single-cell protein, glucose, and sorbitol (Putarau 1969; Coral et al. 2002). One of the goals in biotechnological development is to open the way to utilize microbes in waste bioconversion. Microbe used to treat cellulose-containing wastes could produce extra-cellular enzymes that were able to degrade cellulose material into their smaller components (Bedford and Partridge 2001). The potency of utilizing cellulase is varied. However, there are some constraints in producing it such as the unavailability of superior microbial strains and a lack of knowledge in enzyme production technology. On the other hand, experts from developed countries acknowledge that countries rich in biodiversity, including Indonesia, are a potential source of microbes for bioprocessing (Fox 1994). Cellulase is usually produced by bacteria and fungi. At present, fungi are usually needed in producing cellulase and for the bioconversion process to improve animal feed quality, but there is a constraint arising from the increase of crude fiber content due to the presence of hyphae which is counted as crude fiber (Coral et al. 2002). One of the alternatives is using forest litter decomposer bacteria i.e. Bacillus spp. Bacillus spp. have the biggest number of bacteria, can be found in almost every location, and when chemically tested, they were the most active out of seven genera of bacteria (Jusfah et al. 1995; Yusuf 2000). Litter is organic material residue from dead plants that can be found on the earth's surface or buried in its soil minerals. The speed of the litter decaying process by decomposer

Ubi jalar yang berwarna ungu merupakan sumber antosianin yang berfungsi sebagai antioksidan yaitu dapat menangkap radikal bebas, sehingga berperan untuk mencegah terjadinya penuaan, kanker, dan penyakit degeneratif. Pergeseran pola hidup masyarakat dari makanan tradisional menjadi makanan instan dan cepat saji dapat memicu atau menyebabkan terbentuknya radikal bebas, begitu juga peningkatan jumlah kendaraan yang dapat menyebabkan polusi udara rentan teroksidasi menjadi radikal bebas. Penelitian ini bertujuan untuk melihat pengaruh pengurangan antioksidan dan  antosianin pada pengolahan ubi jalar ungu ( tepung, sirup dan selai dari ubi kukus dan rebus). Ubi jalar yang digunakan adalah ubi jalar ungu lokal. Untuk penentuan uji antosianin digunakan metoda Spektrofotometri dan uji antioksidan dengan metoda DPPH dengan menentukan nilai Ic50. Proses pengolahan ubi ungu menurunkan kadar antioksidan dengan didapatkannya nilai IC50 yaitu ekstrak mentah sangat kuat (5,00 mg/L) dibandingkan kukus (47,82 mg/L) dan rebus (86,22 mg/L). Kadar antosianin ekstrak mentah lebih tinggi dari kukus dan rebus, proses pengolahan pembuatan sirup kukus kadar antosianin lebih tinggi dari selai dan tepung. Penurunan aktivitas antioksidan berbanding lurus dengan penurunan kadar total fenolik dan antosianin serta proses produk olahan dengan urutan mentah, kukus dan rebus

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