The Carbon Isotopic Composition of Trihalomethanes Formed from Chemically Distinct Dissolved Organic Carbon Isolates from the Sacramento-San Joaquin River Delta, California, USA.

Abstract

Dissolved hydrophobic and hydrophilic acids were isolated from samples collected at five channel sites within the Sacramento-San Joaquin Rivers and Delta, California, USA, and from a peat island agricultural drain to examine the relationship between the chemical composition of dissolved organic carbon and the formation of trihalomethane, and to test whether peat island-derived dissolved organic carbon contributed substantially to reactivity. The chemical composition of the isolates was quite variable, as indicated by significant differences in carbon-13 nuclear magnetic resonance spectra and carbon to nitrogen concentrations ratios, though the variability was not consistent with simple mixing of river- and peat-derived dissolved organic carbon. The lowest propensity to form trihalomethane observed was in the peat island agricultural drain sample, suggesting the addition of peat island waters into Delta channels did not increase the amount of trihalomethane formed from channel water dissolved organic carbon. Changes in the chemical and isotopic composition of the isolates suggest the source of the trihalomethane precursors was different among samples and between isolates. The carbon isotopic composition of the trihalomethane formed from the isolates generally tracked the carbon isotopic composition of the isolates themselves, but variability in the carbon isotopic composition of the trihalomethane was higher.

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Seville (sour) Orange Juice: Synephrine Content and Cardiovascular Effects in Normotensive Adults

Abstract

The Seville orange extract Citrus aurantium contains m-synephrine (phenylephrine) and octopamine; it causes cardiac disturbances in animals and is used by humans for weight loss. Juice from the orange (Seville orange juice [SOJ]) is used to “knock out” intestinal cytochrome P450 (CYP) 3A4 in bioavailability studies. The purpose of this study was to determine synephrine and octopamine concentrations in SOJ and SOJ’s cardiovascular effects in normotensive humans. Subjects consumed 8 ounces of SOJ and water in crossover fashion followed by a repeat ingestion 8 hours later. Hemodynamic (heart rate; systolic, diastolic, and mean arterial pressure) measurements followed. Synephrine and octopamine were determined by high-performance liquid chromatography. Hemodynamics did not differ significantly between water and SOJ groups. Mean synephrine concentration of SOJ samples was 56.9 ± 0.52 μg/ml; octopamine was not detected. SOJ ingestion by normotensive subjects is expected to be safe. Individuals with severe hypertension, tachyarrhythmias, and narrow-angle glaucoma and monoamine oxidase inhibitor recipients should avoid SOJ consumption. Persons taking decongestant-containing cold preparations should also refrain from SOJ intake.

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Production of dissolved organic carbon (DOC) and trihalomethane (THM) precursor from peat soils

Abstract

Water passing through the Sacramento-San Joaquin Delta contains elevated concentrations of dissolved organic carbon (DOC) and trihalomethane (THM) precursor relative to upstream waters from the Sacramento River and the San Joaquin River. Drainage from agricultural peat soils has been identified as one of the major sources of DOC and THM precursor. A series of controlled laboratory experiments were conducted to evaluate abiotic and biotic effects on the quantity and the nature of DOC and THM precursors produced from oxidized surface and reduced subsurface soils in the Delta. 

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Photo-oxidation of dissolved organic matter in river water and its effect on trace element speciation

Abstract

To investigate the effect of photodegradation of fluvial dissolved organic matter (DOM) on dissolved trace element distributions, we performed a 3-week incubation of water from the lower Pearl River (Mississippi). The experiment was performed in natural light (with dark controls) and examined both the changes in DOM and changes in physical–chemical speciation of a suite of trace metals. During the incubation, dissolved organic carbon (DOC) decreased in the light by about 20%, whereas ultraviolet light absorbance decreased by nearly 40%; dark controls showed no significant change in DOC. For the trace elements, a variety of behaviors were observed. Some elements (alkali and alkaline earth metals, Mo, Mn, Cd, and Zn) showed no change in concentration or speciation. A number of elements, however, did show significant changes in the light. For example, there was a significant, continuous decrease in dissolved (,0.02-mm) Fe in the light samples during the experiment. This and other speciation results indicate that organically complexed Fe was released during photo-oxidation of the lowmolecular- weight DOM; this was followed by subsequent precipitation of the released Fe as additional colloidal FeOOH. Other elements (Ce, Cu, Cr, Pb, V, and U) also showed decreases in the dissolved (,0.02-mm) fraction with time. Some of these elements, as well as Co and Ni, also showed decreases in their retention by an anion exchange column, likewise implying a decrease in their organically complexed forms.

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Medical Aspects and Applications of Humic Substances

Abstract

Humic substances (HS) comprising one of the largest reservoirs of carbon in nature may originate from different sources. For example, they can be formed as final products of biosynthetic pathways in micro-organisms, degradation and transformation products in plants, synthetic oxidation products of phenolic compounds and as polymers resulting from roasting processes, e.g. coffee roasting. Suprisingly, besides their brown color, which is responsible for the high UV absorption of HS, polymers of the HS type have several features in common  that enable them to interact with other biopolymers as well as with low-molecular weight organic and inorganic compounds and, in particular with metals, thus chelate complexes. fractal structures, neighboring carboxyl and hydroxyl groups, reduction-oxdation and association-dissociation potentials are some of most important biogeochemical component of the Earth's surface. Besides their traditional use as fuel and organic fertilizers, HS are substrates for medical preparations, and also starting materials in the synthesis of specialized industrial products.

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Influence of humic acid on sorption of Co(II), Sr(II), and Se(IV) on goethite

Abstract

This work examined the influence of a leonardite humic acid on the sorption of Co(II), Sr(II), and Se(IV) onto goethite as a function of pH. The sorption of humic acid and ions alone was first studied. The humic acid sorbs appreciably to the goethite surface according to a reversible process, with a maximum sorption of 19 mg of total organic carbon per g of goethite reached at lower pH values (» 5). Cobalt and selenium are significantly sorbed on goethite while strontium is only weakly sorbed. In the presence of humic acid, the cobalt sorption is enhanced in acidic media due to the humic acid sorption on goethite, which modified the surface properties by making it more negative. However, it decreases in alkaline media due to the complexation of Co(II) by soluble humic acid. The sorption of Sr(II) is significantly increased in the presence of humic acid even in alkaline media. The sorption of selenite ions (SeO3 2–) decreases in the presence of humic acid because a competition with humate ions occurs at the surface sites of the goethite. The results presented here constitute a good set of data for modelling the effect of humic acid on the sorption of ions on goethite.

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How DOC Composition May Explain the Poor Correlation Between Specific Trihalomethane Formation Potential and Specific UV Absorbance

Abstract

Trihalomethane formation potential, ultra-violet light absorbance, and aromatic carbon content of dissolved organic carbon in natural water from grab sampling in watersheds across the USA and from detailed sampling in one watershed, the Sacramento-San Joaquin Delta, California, were examined in order to better understand the compositional nature of trihalomethane precursor material. Specific trihalomethane formation potential and specific ultra-violet light absorbance were not tightly correlated in either dataset, indicating that ultra-violet light absorbance cannot be used for accurate prediction of specific trihalomethane formation potential in drinking water derived from a broad spectrum of watershed types. Specific trihalomethane formation potential was not closely related to the aromatic carbon content of dissolved organic carbon isolates or to the partitioning of the dissolved organic carbon by nonionic macroporous resins, suggesting that neither of these measures are related to the compositional features of the dissolved organic carbon responsible for trihalomethane formation.

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Fluorescence properties of organic ligands for copper(II) in Lake Biwa and its rivers

Abstract

Organic ligands for copper(II) were isolated from lake waters in Lake Biwa and its river waters by immobilized metal ion affinity chromatography (IMAC), and were characterized by three-dimensional excitation/emission matrix spectroscopy (3DEEM) and fluorescence quenching titration. The results show that the contribution of total organic ligands was 0.63–4.68% of the bulk dissolved organic matter (DOM), in terms of UV absorbance, in lake and river waters. Three characteristic excitation/emission (Ex/Em) fluorescence peaks were identified in organic ligands from both lake and river waters, at Ex/Em 310–330/ 374–434 nm (Peak A), 250/414–454 nm (Peak B), and 260–270/306–330 nm (Peak C). Peaks A and B were referred to as humic-like fluorescence, Peak C as protein-like fluorescence. All Ex/Em maxima of organic ligands in lake waters were shifted towards shorter wavelength, and the fluorescence intensities were higher than those in river waters. The results of fluorescence quenching titration show that the IMAC ligands were weak ligands, with conditional stability constants (logK′CuL) around 7.27 for river ligands, and 7.84–9.23 for lake ligands. The differences of fluorescence properties indicate the variability of fluorescent ligands between river terrestrial and lake aquatic environments.

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Hydrolyzing metal salts as coagulants

Abstract

Aluminium and ferric salts are widely used as coagulants in water and wastewater treatment. They are effective in removing a broad range of impurities from water, including colloidal particles and dissolved organic substances. Their mode of action is broadly understood in terms of essentially two mechanisms: charge neutralization of negatively charged colloids by cationic hydrolysis products and incorporation of impurities in an amorphous precipitate of metal hydroxide. The relative importance of these two mechanisms depends on many factors, especially pH and coagulant dosage. Alternative coagulants based on prehydrolyzed forms of aluminium or iron can be more effective than the traditional materials in many cases, but their mode of action is not completely understood, especially with regard to the role of charge neutralization and hydroxide precipitation. Basic principles of colloid stability and metal ion hydrolysis are briefly reviewed, and the action of hydrolyzing metal coagulants is then discussed, with some examples from recent experimental studies. Although it is possible to interpret results reasonably well in terms of established ideas, there are still some uncertainties that need to be resolved.

Keyword: Hydrolyzing, metal salts, coagulants

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Kesetimbangan Adsorpsi Optional Campuran Biner Cd(II) dan Cr(III) dengan Zeolit Alam Terimpregnasi 2-merkaptobenzotiazol

ABSTRACT

Natural zeolite is one of adsorbents widely used in adsorption processes to treat water polution caused by heavy metal waste. In some cases, the modification of the zeolit active surface is important to improve its adsorpability and its selectivity. Characteristic of modified natural zeolite can be obtained from the analysis of adsorption equilibrium data which useful for adsorption process design. The aim of the research is to find and analyzing the adsorption equilibrium data for binary mixture adsorption process of Cd and Cr metals using the modified natural zeolite which impregnated with 2-metrcaptobenzotiazole (zeolite-MBT). The adsorption equilibrium experiments were carried out in a flask batch method using a shaker bath with experimental temperatures were varied from 27°C to 50°C. An amount of 0.1 gram of zeolite-MBT adsorbent was immersed in 60 ml of Cd and or Cr solution then shook until the equilibrium condition (6 hours) was reached. The quantity of metal ionic adsorbed was measured through the concentration of metal solution at equilibrium condition. Each series of equilibrium data were obtained by varying the initial solution concentration in such a way that they could be ploted to create the adsorption isotherm curve. The Langmuir competitif model was used to draw the adsorption isotherm curve for the binary mixture of Cd and Cr by zeolit-MBT adsorbent. The smallest relative mean error correction, i.e. 12.9% and 23 % for Cd and Cr adsorption respectively. Separation performance in the adsorption process of Cd and Cr by the zeolit-MBT adsorbent is five to eight times better than the zeolit-Na adsorbent that wide commercially being used.

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Palladium-Catalyzed Alkylation of Unactivated Olefins

Abstract

Reaction of a 3-butenyl -diketone with a catalytic amount of PdCl2(CH3CN)2 in dioxane at room temperature led to olefin hydroalkylation and formation of the corresponding 2-acylcyclohexanone in good yield as a single regioisomer. Deuterium-labeling experiments for the hydroalkylation of 7-octene-2,4-dione were in accord with a mechanism involving outer-sphere attack of the pendant enol on a palladium-complexed olefin to form a palladium cyclohexyl species, followed by palladium migration via iterative -hydride elimination/ addition and protonolysis from a palladium enolate complex. In comparison to a 3-butenyl -diketone, reaction of a 4-pentenyl -diketone with a catalytic amount of PdCl2(CH3CN)2 in the presence of CuCl2 led to oxidative alkylation and formation of the corresponding 2-acyl-3-methyl-2-cyclohexenone in good yield as a single isomer.

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Program Dinamik

Abstract

Tidak seperti program linier, Program Dinamik (PD) tidak mempunyai standar formulasi matematik. PD lebih merupakan suatu cara umum untuk melakukan optimasi dengan persamaan matematik yang cocok dengan masalah yang dihadapi. Insight dan ingenuity dibutuhkan untuk mengenali penggunaan PD dalam menyelesaikan masalah lapangan. Cara terbaik penyampaian PD adalah dengan mengenalkan beberapa permasalahan yang dapat diselesaikan dengan PD.

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METODE OPTIMASI SELEKSI FITUR DENGAN ALGORITMA FAST BRANCH AND BOUND

Abstract

Integer Programming merupakan salah satu pemodelan untuk pencarian suatu solusi yang optimum dari suatu masalah. Banyak sekali kasus di sekitar kita yang memerlukan implementasi integer programming agar didapatkan suatu solusi paling optimal yang pada akhirnya menambah keuntungan. Ada banyak cara untuk menyelesaikan integer programming, misalnya dengan cara program linear standar yaitu dengan menggunakan grafik. Cara lainnya adalah dengan mengaplikasikan algoritma Branch and Bound. Makalah ini mencoba untuk menjelaskan bagaimana suatu integer programming diselesaikan dengan pengaplikasian algoritma Branch and Bound.

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Penggunaan Metode Branch And Bound With Search Tree Untuk Menyelesaikan Persoalan Pedagang Keliling Pada Graf Lengkap Sebagai Pengganti Metode Exhaustive Enumeration

Abstract

Persoalan pedagang keliling merupakan persoalan yang cukup terkenal di dalam teori graf, Implementasinya sangat banyak digunakan di dalam kehidupan sehari-hari, dari masalah yang berhubungan dengan pengiriman barang sampai yang berhubungan dengan industri pabrik Oleh karena itu, saya memilih persoalan ini sebagai tema dari makalah saya. Saya juga membatasi masalah yang ada yaitu pemecahan TSP graf lengkap (Kn) untuk lebih memberikan kejelasan yang dalam. Makalah ini membahas sebuah metode yang dapat digunakan untuk menyelesaikan persoalaan pedagang keliling (TSP) pada graf lengkap. Kita dapat melihat kemampuan dari metode ini dalam memecahkan persoalaan dari segi kompleksitas waktu dan kemudahan dalam penggunaan. 

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APLIKASI ALGORITMA BRANCH AND BOUND UNTUK MENYELESAIKAN INTEGER PROGRAMMING

Abstract

Integer Programming merupakan salah satu pemodelan untuk pencarian suatu solusi yang optimum dari suatu masalah. Banyak sekali kasus di sekitar kita yang memerlukan implementasi integer programming agar didapatkan suatu solusi paling optimal yang pada akhirnya menambah keuntungan. Ada banyak cara untuk menyelesaikan integer programming, misalnya dengan cara program linear standar yaitu dengan menggunakan grafik. Cara lainnya adalah dengan mengaplikasikan algoritma Branch and Bound. Makalah ini mencoba untuk menjelaskan bagaimana suatu integer programming diselesaikan dengan pengaplikasian algoritma Branch and Bound. 

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TEKNIK RISET OPERASI: Pengembangan Teknologi Komputer & Informasi sebagai Langkah Rehabilitasi Tuna Netra di Indonesia

Abstract

Indera penglihatan adalah salah satu sumber informasi vital bagi manusia. Tidak berlebihan apabila dikemukakan bahwa sebagian besar informasi yang diperoleh oleh manusia berasal dari indera penglihatan, sedangkan selebihnya berasal dari panca indera yang lain. Dengan demikian, dapat dipahami bila seseorang mengalami gangguan pada indera penglihatan, maka kemampuan aktifitasnya akan jadi sangat terbatas, karena informasi yang diperoleh akan jauh berkurang dibandingkan mereka yang berpenglihatan normal. Hal ini, apabila tidak mendapat penanganan/rehabilitasi khusus, akan mengakibatkan timbulnya berbagai kendala psikologis, seperti misalnya perasaan inferior, depresi, atau perasaan hilangnya makna hidup. 

Di Indonesia alat bantuk utama untuk tuna netra yaitu tongkat khusus. Akan tetapi alat ini memiliki berbagai macam keterbatasan, sehingga hanya sebagian kecil saja informasi yang dapat dipahami dari lingkungan dimana dia berada. Dewasa ini, perkembangan teknologi yang pesat membuka peluang pengembangan berbagai alat bantu yang memanfaatkan berbagai disiplin ilmu, seperti halnya GPS, computer vision, virtual reality, SMS Speech, serta berbagai perangkat lunak dan perangkat keras ntuk memberikan informasi yang lebih utuh bagi tuna netra.

 

Keyword: Teknik Riset Operasi, Teknologi Komputer, Rehabilitasi Tuna Netra

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TINGKAT MOTILITAS SPERMATOZOA DAN PEMBUAHAN SEL TELUR TIRAM MUTIARA (Pinctada maxima) DENGAN PEMBERIAN LARUTAN AMONIA

Abstract

Indonesia merupakan negara kepulauan yang memiliki perairan yang luas sehingga mempunyai potensi yang cukup besar untuk pemanfaatan sumber hayati laut yang terkandung didalamnya, salah satu potensi besar yang ada diperairan Indonesia adalah tiram mutiara. Seiring dengan bertambahnya usaha budidaya tiram mutiara maka meningkat pula kebutuhan akan pengadaan benih tiram mutiara, dan sampai saat ini pengadaan benih masih banyak tergantung dari alam. Untuk mengatasinya maka perlu dilakukan usaha pembenihan yang dapat menjamin kelangsungan usaha budidaya tiram mutiara dan dapat menjaga kelestarian komoditas tersebut dari kepunahan. Tujuan dari penelitian ini adalah mengetahui tingkat motilitas spermatozoa dengan penambahan larutan ammonia, mengetahui tingkat keberhasilan pembuahan sel telur oleh spermatozoa yang telah mendapatkan perlakuan penambahan larutan ammonia dan mendapatkan konsentrasi larutan ammonia yang paling tepat untuk meningkatkan persentase pembuahan sel telur tiram mutiara. 

Rancangan percobaan yang digunakan dalam penelitian aini adalah rancangan acak lengkap (RAL) dengan lima perlakuan dan tiga kali ulangan, perlakuan yang diberikan adalah pemberian konsentrasi larutan ammonia yang berbeda. Konsentrasi yang digunakan adalah 0 % ,0,05%, 0,1 %, 0,15 % dan 0,2 % dari volume sampel. Hasil penelitian menunjukan bahwa semua perlakuan yang dicobakan memberikan perbedaan pengaruh yang sangat nyata terhadap motilitas spermatozoa dan pembuahan sel telur tiram mutiara.

Kata kunci : amonia,motilitas,pembuahan,tiram mutiara

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Efek Sitotoksik Suatu Protein Seperti Ribosome Inactivating Proteins yang Bersifat Asam dari Daun Mirabilis Jalapa L. Pada Sel Kanker

Cytotoxic effects of an acidic Ribosome-inactivating Protein like protein isolated from Mirabilis jalapa L. leaves on cancer cell-lines

Sudjadi *, Lucia D Witasari, Modesta T Sadarum, Nia Nastity dan Sismindari

Fakultas Farmasi Universitas Gadjah Mada Yogyakarta

Abstract

Most purification approaches of Ribosome-inactivating Proteins (RIPs) used a cation exchange chromatography resulting highly basic proteins, such as MJ-30 isolated from Mirabilis jalapa leaves. The M.jalapa unbounded protein fractions of the column showed cleavage activity on supercoiled double stranded DNA and possesed cytotoxic effects on cancer cell lines. So the purification and characterization of the acidic protein was needed to be done. Total proteins of M.jalapa leaves was collected from precipitating process of the extract using ammonium sulphate untill saturated. After dialysis, the proteins was applied into the weak base anion exchanger Ionenaustaucher Typ II. The bounded proteins was eluted with 0.0 to 0.5 M NaCl gradient in phosphate buffer. Active protein fractions were determined by supercoilded DNA cleavage activity and then cytotoxic activity was testes. Results showed that protein fraction eluted at 0.35 – 0.40 M NaCl possesed cleavage activity on supercoiled DNA. The acidic protein, MJ-C, was toxic on HeLa, Myeloma and T47D cell lines, with the LC50 of 4.3 μg/mL, 7.4 μg/mL and 27.8 μg/mL, respectively. The MJ-C was more potent than the basic protein MJ-30.

Keyword : acidic RIP, cytotoxic, Mirabilis jalapa,

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Beberapa Oligomer Stilbenoid dari Tumbuhan Shorea multiflora Burck

Abstract

Two dimers of stilbenoids, (-)-balanocarpol (4), and (-)-ampelopsin A (5), along with a tetramer (-)-hopeaphenol (6) were isolated from the stem bark of Shorea multiflora Burck (Dipterocarpaceae), locally known as Meranti. Their structures were determined by physical and UV, IR, 1H-NMR, and 13C-NMR spectroscopic data.

Keyword : (-)-ampelopsin A, (-)-balanocarpol, Dipterocarpaceae, (-)-hopeaphenol, Meranti, Shorea multiflora Burck.

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ESTERIFIKASI PATCHOULI ALKOHOL HASIL ISOLASI DARI MINYAK DAUN NILAM (PATCHOULI OIL)

Abstract

Minyak atsiri yang disebut juga minyak eteris atau minyak terbang banyak diperlukan dalam kehidupan sehari-hari. Dengan kemajuan teknologi di bidang minyak atsiri maka usaha penggalian sumber-sumber minyak atsiri dan pendayagunaannya dalam kehidupan manusia semakin meningkat. Minyak atsiri tersebut digunakan sebagai bahan pengharum atau pewangi pada makanan, sabun, pasta gigi, wangi-wangian dan obat-obatan. Untuk memenuhi kebutuhan itu, sebagian besar minyak atsiri diambil dari berbagai jenis tanaman penghasil minyak atsiri.

Nilam (Pooostemon cablin BENTH ) merupakan salah satu jenis tanaman yang dapat menghasilkan, minyak atsiri dan sudah lama dikenal oleh masyarakat Indonesia yaitu sebagai pengharum pakaian. Di setiap daerah, nilai mempunyai nama berbeda-beda, di Purwokerto disebut dengan "dilem wangi", di Tapanuli Selatan disebut "singgolom", sedangkan untuk nilam yang berbunga di Jawa sering disebut "dilem kembang" dan di Aceh dikenal dengan nama "nilam bukit" (Poqostemon hevneanus BENTH). Nilam selain dapat dijual dalam bentuk daun kering juga dapat berupa minyak.

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