The Nitration of Monoalkyl Benzene and the Separation of its Isomers by Gas Chromatography

The nitronium ion, N02 +, is believed to be the attacking electrophile in the nitration reaction. When this reaction is carried out on monoalkyl substituted benzene, the substituents playa major role in determining the products obtained. The reaction also depends on the different methods of nitration employed. This report describes the method of determining the percentage of each isomer produced by gas chromatography

PENGARUH EKSTRAK KULIT JENGKOL DAN DAUN SRI REJEKI TERHADAP MORTALITAS KEONG EMAS (Pomecea canaliculata)

Tanaman padi merupakan bahan makanan pokok penduduk Aceh. Untuk mengatasi kebutuhan makanan pokok masyarakat yang terus meningkat maka diperlukan upaya keras dalam peningkatan produksi padi yang baik kualitas maupun kuantitas. Permasalahan yang sering dihadapi oleh petani antara lain hama, penyakit, dangulma. Beberapa jenis hama yang sering menyerang tanaman padi sehingga menyebabkan kerugian yang tidak kecil bagi petani padi, antara lain keong emas (Pomecea canaliculata L). Tujuan penelitian ini untuk Mengetahui ektrak kulit jengkol dan daun sri rejeki sebagai pengendalian hama keong emas dan Mengetahui konsentrasi ekstrak kulit jengkol dan daun sri rejeki yang tepat untuk pengendalian hama keong emas. Penelitian ini menggunakan metode ekprimen dan Rancangan Acak Lengkap Faktorial (RALF) dengan 9 perlakuan. Variabel yang digunakan dalam penelitian ini kulit jengkil (J) dan daun sri rejeki (K). Perlakuan ekstrak kulit jengkol dan daun sri rejeki dengan kosentrasi 5%, 10% dan 15%, pengamatan keong emas (Pomecea canaliculata L) dilakukan selama 24, 48, dan  72 jam. Hasil penelitian menunjukan bahwa perlakuan kosentrasi ekstrak kulit jengkol dan daun sri rejeki dapat dijadikan pengendalian hama keong emas (Pomecea canalikulata L) dikarenakan dapat terjadi gejala kematian keong emas (Pomecea canalikulata L) dan mortalitas keong emas (Pomecea canalikulata L). Kosentrasi yang paling optimal terhadap gejala kematian dan mortalitas keong emas (Pomecea canalikulata L) yaitu pada kosentrasi 15% ekstrak pada perlakuan P9 yaitu K3J3

Chemical Constituents of Piper aduncum Linn (Piperaceae)

The leaves of Piper aduncum were studied for its chemical constituents. The non-polar component has been identified spectroscopically as dillapiole or 1allyl- 4, 5-methylenedioxy-2, 3-dimethoxybenzene while from the polar fraction 2, 6-dihydroxy-4-methoxydihydrochalcone has been isolate

Chemical diversity of Malaysian flora: potential source of rich therapeutic chemicals

Although people all over the world has been using various kind of plant species as medicine for the treatment of diseases since millennia, the isolation and identification of the active principals were only achieved in the 19th century. This can be considered the beginning of remarkable achievements in the discovery of therapeutic agents from plants. Some of these early discoveries are the isolation of morphine from Papaver somniferum, aneasthetic cocaine from Erythroxylum coca, antimalarial quinine from Cinchona officinalis etc. Numerous other therapeutic molecules have been discovered since and the general health of the world population improved dramatically, the search for new drugs from plants, microorganisms and marine source continued until today. With the availability of modern techniques, instrumentations and advancement in scientific knowledge have led to faster phase of discovery of therapeutic chemicals with wide ranged of structural types. It has been estimated that less than 1% of plant species has been examined in detailed for their therapeutic potential and currently about 120 pharmaceutical products in used are derived from plants and 75% of these were discovered from plants used in traditional medicine. In this presentation we will look into the diversity of chemicals isolated and fully characterized from our own rich Malaysian tropical flora. Amongst the various type of natural products identified are the many classes of alkaloidsi lignans, terpenoids, sulphur-containing compounds, flavonoids, xanthones, glycosides, chalcones etc. Particular attention was made on certain genus of plants from the Rutaceae family (lemon family) due to the presence of interesting chemical structures and exhibiting good biological activity. From the various types of compounds identified, certain classes of alkaloids, coumarins and sulphur containing compounds have shown excellent antimicrobial and anticancer activity against various cancer cell lines. With the availability of high-throughput screening tests for bioassay-guided fractionation and combinatorial synthesis toot natural product from plant source particularly from tropical plants, will continue to supply banks of compounds for future drug developments

Phytotoxicity of phenolic acids extracted from palm oil dry solids

A study on the extraction of palm oil dry solids (PODS) was conducted to identify the water-soluble compounds involved in the phytotoxicity of PODS. The aqueous extract of PODS was sequentially partitioned using various organic solvents. Each of the dried extracts was bio assayed for inhibitory activity on the growth of tomato radicles. Maximum inhibition of radicle growth was observed in the diethyl ether extract, resulting in 53.3% growth compared with control. Further separation of the ether fraction using column chromatography resulted in a single toxic fraction, RM10, which caused only 30% radicle growth. The fraction was compared with 14 synthetic phenolic compounds using thin-layer chromatography and was observed to be similar to four of the compounds. Further analysis by high performance liquid chromatography revealed that the RM10 fraction comprised vanillic acid. However, the RM10 fraction was more inhibitory to the growth of tomato radicles than synthetic vanillic acid

Arborine, a Larval Growth Inhibitor from Glycoslnis pentaphylla

Arborine (I), a quinazolone alkaloid was isolated from the leaves of Glycosmis pentaphylla (Rutaceae) and was found to have a growth inhibitory effect on the larvae of Drosophila melanogaster

ISOLASI SENYAWA DARI KORTEKS AEGLE MARMELOS (ISOLATION OF COMPOUNDS FROM EGLE MARMELOS BARK USED PETROLEUM

ABSTRACT: Aegle marmelos Con. is the tree with the local name Maja (Java), the member of Rtitaceae family. The plant is used in traditional medicine treatment. Researches on Aegle marnielos Corr have been reported, so that the numbers of compounds have been known. such as alkaloid. cumarine derivatives, cinnamate derivatives etc. The plant material was collected from Godean. Yogyakarta. The dry powder of "Maja" barks was extracted with petroleum ether. The obtained crude extract was subjected on the vacuum column and continued by gravity\u27 column chromatography. The isolated compounds were determined their molecular structure by interpreting the spectral data (UV, IR. Mass and \u27H & \u273C NMR). Working procedure has afforded to isolate two triterpenes. lupenone and lupeol, also the white crystals have been obtained which consist of two compounds. these are stigmasterol and sitosterol. Key words : lupenone, iupeol, phytosterol. bark, Aegle marmelo

Jatrofolon A danJatrofatrion: Dna Diterpena dariJatropha gossypifolia

From. the dried :oot extrac~ ofJatropha gossypif~lia ~Euphorbiaceae), two diterpene compounds, jatropholone A andJatrophatnone, were zsolated. Structural eluczdatzon ofthe compounds was camed out by using spectroscopic method and results were compared with published data

Toxicity, antifeedant, egg hatchability and adult emergence effect of Piper nigrum L. and Jatropha curcas L. extracts against rice moth, Corcyra cephalonica (Stainton)

Petroleum ether extract of black pepper, Piper nigrum and physic nut, Jatropha curcaswere shown to have insecticidal efficacies against rice moth, Corcyra cephalonica(Stainton). The C. cephalonica 3rd instar larvae were shown to have similarities susceptibility to petroleum ether extract of Piper nigrum and J. curcas with LC50 values of 12.52 and 13.22 µL/ml, respectively. In a bioassay using no-choice tests, the parameters used to evaluate antifeedant activity were relative growth rate (RGR), relative consumption rate (RCR), efficiency on conversion of ingested food (ECI) and grain protection or feeding deterrence indices (FDI). Both extracts showed high bioactivity at all doses against C. cephalonica larvae and antifeedant action was increased with increasing plant extract concentrations. The petroleum ether extract of P. nigrum and J. curcas showed strong inhibition on egg hatchabilities and adult emergence of C. cephalonica at the lowest concentration. Based on the results of this study, petroleum ether extracts of P. nigrum andJ. curcas could be used in IPM program for rice moth

Bioassay-guided isolation of antifungal plumericin from Allamanda species (Apocynaceae).

Anthracnose is an economically important disease that can cause 10 to 80% yield reduction in the market with its typical symptoms of dark spots, sunken necrotic tissues and concentric rings of acervuli on fruits. One of the important methods to control the disease is by using antifungal agents derived from plant. Preliminary study indicated that the extracts of Allamanda species have the potential to be developed as the target agent. Five Allamanda species were extracted and screened for antifungal activity against plant pathogenic fungus Colletotrichum gloeosporioides by using poison agar technique. The three chloroform extracts of A. blanchetti, A. cathartica ‘Alba’ and A. cathartica ‘Jamaican Sunset’ exhibited potent inhibitory effects and suppressed the mycelial growth of C. gloeosporioides by up to about 70%. Further study by bioautography-guided fractionation of the extracts led to the isolation and identification of tetracyclic sesquiterpene plumericin as the antifungal agent. The structural determination of the compound was carried out by interpreting the IR, MS, 1D-NMR and 2D-NMR spectral data