Rudianto Amirta

Ceriporic acid C, a hexadecenylitaconate produced by a lignin-degrading fungus, Ceriporiopsis subvermispora.

A lignin-degrading basidiomycete, Ceriporiopsis subvermispora produces a series of alkyl- and alkenylitaconates (ceriporic acids). Previously, two alkylitaconic acids with tetradecyl and hexadecyl side chains were isolated and identified as 1-heptadecene-2,3-dicarboxylic acid (ceriporic acid A) and 1-nonadecene-2,3-dicarboxylic acid (ceriporic acid B). In the present study, one hexadecenylitaconate (ceriporic acid C) was isolated and its chemical structure was analyzed by glycolation and subsequent (1) trimethylsilation, or (2) acetalation with acetone and acetone-d6. Analyses of the isolated metabolite demonstrated that the hexadecenylitaconic acid was (Z)-1,10-nonadecadiene-2,3-dicarboxylic acid. The structure of the side chain in ceriporic acid C was the same as that of hexadecenylcitraconate, chaetomellic acid B. Thus, it was found that ceriporic acids share close structural similarity with alk(en)yl citraconate derivatives, chaetomellic acids and other lichen lactones, protolichesterinic, lichesterinic, and murolic acids.

A new 4-arylflavan from the pericarps of Horsfieldia motleyi displaying dual inhibition against α-glucosidase and free radicals

Abstract In search for effective antidiabetic agents that simultaneously inhibit α-glucosidase and scavenge free radicals, Horsfieldia motleyi showed promising bioactivity according to the proposed criteria. Bioassay-guided isolation of pericarp extract yielded a new 4-arylflavan named myristinin G (6), whose gross structure and absolute configuration were verified by 2D NMR and electronic circular dichorism (ECD). Myristinin G (6) concomitantly inhibited α-glucosidases (IC50 107.0 and 126.9 μM) and free radicals (SC50 54.3 and 279.9 μM). Of interest, 6 inhibited sucrase through an uncompetitive manner, which is rare in nature.

Effect of wood, bark and leaf extracts of Macaranga trees on cytotoxic activity in some cancer and normal cell lines

The genus of Macaranga (Euphorbiacaceae) has 250 species of which 160 species are endemic in Kalimantan and New Guinea. They grow as pioneer trees and are used as traditional medicines in the Asian regions. This experiment concerns cytotoxicity in both cancer and normal cells of their methanol extracts from wood, bark and leaf parts. Some of them have not yet reported its cytotoxic activity in those cell lines. The 21 methanol extracts were prepared from seven Macaranga tree species (Macaranga bancana, Macaranga gigantea, Macaranga hullettii, Macaranga pruinosa, Macaranga tanarius, Macaranga trichocarpa and Macaranga triloba). The MTT assay was used to evaluate cytotoxic activity of extracts in cancer cell lines [human breast cancer (MCF-7), mouse melanoma (B16 melanoma), human colon cancer (HCT116), human cervical adenocarcinoma (HeLa)] and normal cell lines [human normal fibroblast (TIG-1) and normal human dermal fibroblast (NHDF)]. The leaf extracts of M. pruinosa, M. tanarius, M. trichocarpa showed more cytotoxicity than wood and bark in all cancer cell lines. In addition, the 5-fluorouracil was used as a positive control. These findings indicated the extracts from leaves of M. pruinosa, M. tanarius and M. trichocarpa had more potential than wood and bark parts to be developed as anti-cancer agents.

Mixing of acacia bark and palm shells to increase caloric value of palm shells white charcoal briquette

Indonesia is greatly rich in biomass resources. Acacia bark waste utilization as a source of biomass is still very low, where as 10-20% of the potential of the wood. On the other hand waste palm shells have been partly utilized as boiler fuel oil plant as much as 62.4%, but the rest is still a waste pile or to the hardening of the estate path. This study aims to determine the effect of mixing an acacia bark with palm shells to increase the calorific value of palm shell white charcoal briquettes. The study was conducted by making white charcoal briquettes mixing 7% the acacia bark against of palm shells. As well as white charcoal briquettes control without any acacia bark. Then molds the briquettes in pyrolysis temperature at 600 ° C, 700 ° C and 800 ° C for pyrolysis time within 2 hours, 4 hours, and 6 hours. And the results of briquettes analysis in calorific value. The results showed that the caloric value of palm shell white charcoal briquettes increased from 29691.14 Kcal / kg to 31941.50 Kcal / kg.