The dehaloperoxidase-hemoglobin (DHP) from the terebellid polychaete Amphitrite ornata is a multifunctional hemoprotein that catalyzes the oxidation of a wide variety of substrates, including halo/nitrophenols, haloindoles, and pyrroles, via peroxidase and/or peroxygenase mechanisms. To probe whether substrate substituent effects can modulate enzyme activity in DHP, we investigated its reactiviy against a panel of o-guaiacol substrates given their presence (from native/halogenated and non-native/anthropogenic sources) in the benthic environment that A. ornata inhabits. Using biochemical assays supported by spectroscopic, spectrometric, and structural studies, DHP was found to catalyze the HO-dependent oxidative dehalogenation of 4-haloguaiacols (F, Cl, and Br) to 2-methoxybenzoquinone (2-MeOBQ). O labeling studies confirmed that O atom incorporation was derived exclusively from water, consistent with substrate oxidation via a peroxidase-based mechanism. The 2-MeOBQ product further reduced DHP to its oxyferrous state, providing a link between the substrate oxidation and O carrier functions of DHP. Nonnative substrates resulted in polymerization of the initial substrate with varying degrees of oxidation, with 2-MeOBQ identified as a minor product. When viewed alongside the reactivity of previously studied phenolic substrates, the results presented here show that simple substituent effects can serve as functional switches between peroxidase and peroxygenase activities in this multifunctional catalytic globin. More broadly, when recent findings on DHP activity with nitrophenols and azoles are included, the results presented here further demonstrate the breadth of heterocyclic compounds of anthropogenic origin that can potentially disrupt marine hemoglobins or function as environmental stressors, findings that may be important when assessing the environmental impact of these pollutants (and their metabolites) on aquatic systems.

Moringa leaf (Moringaoleifera) is a plant that grows in Indonesia with high nutritional content. This plant has biological activity as antidiabetic, blood pressure-lowering, and antioxidant. This study analyzes the nutritional content of Moringa leaf extract, especially amino acids, minerals and determines its antioxidant. Analysis of total amino acid content has been carried out by HPLC (High performance liquid chromatography) method, minerals with ICP-OES (Inductive coupled plasma-optical emission spectroscopy) and antioxidant activity by DPPH (1,1-diphenyl-2-picrylhydrazyl) method. The analysis of Moringa leaf extract has obtained 15 kinds of amino acids, namely: threonine (9403.09), lysine (11694.16), leucine (18087.41), isoleucine (9321.59), phenylalanine (17236.01), valine (11183.48), methionine (5684.68), tryptophan (2577.82) while non-essential amino acids include histidine (9965.39), proline (10068.07), tyrosine (8641.63), aspartate acid (16585.76), glycine (13027.13), arginine (13123.94), alanine (14474.52), glutamate acid (30106.87), serine (10055.98), cysteine (470.37) in ppm. The analysis of minerals has obtained 13 essential minerals included Al, Ca, Co, Cr, Cu, Fe, K, Mg, Mn, Ni, P, Se, Zn. The highest mineral is shown for selenium (1097.84 ppm) and chrome (919.99 ppm) at the second highest order. Sodium (68.83 ppm) and magnesium (60.84 ppm) is found as minerals with low concentrations. The antioxidant test has shown weakness activity with an average IC50 value of 9.901 μg/mL, using ascorbic acid as a positive control with IC50 values of 196.892 μg/mL. The analysis results of amino acids, minerals, and antioxidant activity show that Moringa leaves are very potential for human nutrients.

Buah merah (Pandanus conoideus Lam.) merupakan tanaman endemik yang tumbuh di wilayah Papua. Berdasarkan penelitian sebelumnya buah merah mengandung beberapa senyawa aktif dengan kadar yang cukup tinggi, diantaranya karotenoid, tokoferol, betakaroten, α tokoferol, serta asam lemak seperti asam oleat, asam linoleat, asam linolenat, dan asam dekanoat. Kandungan tokoferol yang cukup tinggi dalam buah merah memiliki aktivitas sebagai antioksidan. Penelitian ini bertujuan untuk menentukan kapasitas antioksidan ekstrak etanol buah merah (Pandanus conoideus Lam.) dengan metode FRAP. Sebanyak tiga replikasi ekstrak etanol buah merah diukur kapasitas antioksidannya dengan menggunakan larutan standar α-tokoferol pada spektrofotometer UV-Vis pada panjang gelombang maksimum 757 nm. Hasil penelitian menunjukkan bahwa, sampel ekstrak etanol buah merah (Pandanus conoideus Lam.) memiliki aktivitas total antioksidan dengan aktivitas sebesar 1,392 x 10-3 g ATE/g ekstrak.

HAL is a multi-disciplinary open access archive for the deposit and dissemination of scientific research documents, whether they are published or not. The documents may come from teaching and research institutions in France or abroad, or from public or private research centers. L'archive ouverte pluridisciplinaire HAL, est destinée au dépôt et à la diffusion de documents scientifiques de niveau recherche, publiés ou non, émanant des établissements d'enseignement et de recherche français ou étrangers, des laboratoires publics ou privés.

Indonesia is a maritime country with the potential fisheries resources. However, utilization only revolves around the meat, while other parts have not been used optimally, especially fish bones which have the potential to produce collagen, so it needs to be developed. The aims of this study ware extracted collagen from bone of Lutjanus sp. and determine its the Anticancer activity. The collagen was extracted by using hydroextraction method and identification by FTIR. The initial screening anticancer activity was done by using Brine Shrimp Lethality Test (BSLT) method for toxicity assay. The results showed that the yield of collagen was 4.535% with protein concentration was 8,815 mg/mL. Identified collagen from spectrum of amide A, B, I, II, and III at 3421.72; 2926.01; 1651.07; 1541.12; 1240.23 cm-1. The toxicity test was shown in LC50 values of  8,760 μg/mL. The collagen from Lutjanus sp. bone can be used as natural anticancer agent.

This research aims to produce DAG of the VCO through the substrate reaction of trans-esterification using lipase enzymes specifically C18-20 from rice bran (Oryza Sativa L.) immobiled of activated carbon as a catalyst. Phases of this research starts with the enzyme lipase do immobile using activated carbon; next enzymes of immobile used to produce DAG through the trans-esterification reaction using a VCO as a substrate and methanol as ko-substrate; DAG and methyl ester produced identified using FTIR instrument and GC-MS instruments. The results showed that there were three compounds DAG and three compound methyl ester produced trans-esterification reaction, namely (1) 1-laurin, 3-heksanoin esters of glycerol; (2) 2-laurin, 3-oktanoin esters of glycerol; (3) 1-laurin, 3-heksanoin esters of glycerol; (4) methyl ester oleic; (5) methyl ester stearic acids; and (6) methyl ester arachidat.

The pattern of disease development has shifted from infectious diseases to degenerative diseases that are triggered by a free radical. The body needs an antioxidant that able to ward off free radicals. One of the potential natural resources is brown algae that contain bioactive compounds and widely used in medicine and the pharmaceutical industry. This research aims to identify the effectiveness of brown algae (Padina australis) extract as a natural antioxidant agent. This research was carried out in several steps, including algae extraction by sonicator method, phytochemical test to identify secondary metabolites in extract and antioxidant test by using DPPH method. The results showed that the extract of brown algae (Padina australis) contained flavonoids, alkaloids, saponin, and steroids. It also has antioxidant activity with an IC50 value of 102,590 µg/mL.

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