Antioxidative constituents from twig and leaves of jasminum sambac / Nurul Fatin Fakhira Mohd Padli ... [et. al.]

This study aimed to investigate new antioxidative constituents from twig and leaves of Jasminium sambac (Oleaceae family) as potent antioxidant sources. The antioxidant behaviour of each extract from twig and leaves of J. sambac was assessed qualitatively by spraying the thin layer chromatography (TLC) of extracts with 2,2-diphenyl-1-picrylhydrazyl (DPPH) and quantitatively by DPPH radical scavenging method. The collection of antioxidative constituents was carried out using centrifugal chromatography. The chemical structures of all constituents were identified from Gas Chromatography Mass Spectrometer (GCMS). The qualitative Thin Layer Chromatography (TLC) screening of antioxidants showed that all types of extracts from J. sambac leaves demonstrated moderate antioxidant behaviour as well as the extracts from twig parts. The quantitative DPPH radical scavenging activity of leaves and twig extracts revealed dichloromethane (DCM) extract scavenged DPPH free radicals more effective at IC50of 6.24 ppm and 5.22 ppm respectively compared to petroleum ether extract and methanol extract where both extracts exhibited IC50more than 100 ppm. The antioxidative constituents isolated from DCM extract of twig of J. sambac were recognized as isoamyl nitrite and benzophenone whereby benzophenone was also found in DCM extract of J.sambac leaves. Thus, J. sambaccan be considered as a promising source of bioactive compounds with potent antioxidant properties which can be utilized as baseline information to overcome health disorders

SURFACE MORPHOLOGY AND CHEMICAL COMPOSITION OF NAPIER GRASS FIBERS (Morfologi Permukaan dan Komposisi Kimia Gentian Rumput Napier)

Abstract A cellulosic component of Napier grass has high potential for the ethanol production. The presence of hemicelluloses, lignin and cellulose in Napier grass fiber can affect the ethanol production. The aim of this study is analyzed the effect of different pretreatment condition (2% of acetic acid and 2% of sodium hydroxide) on the chemical composition and observe the fiber surface morphology of the Napier grass fibers. The fiber surface morphology was observed using Scanning Electrone Microscope (SEM). The result of different pretreatment condition showed that 2% of acetic acid treatment have the highest percentage of cellulose followed by 2% of sodium hydroxide treatment and untreated sample. The hemicellulose content is reduced when treated with acid and alkali. Based on the fiber morphology characterization, acid and alkali pretreatment condition showed that the surface impurities on the fiber were removed. This study suggested that the acid and alkali treatment of Napier grass fibers has a potential to enhance the ethanol production because it can reduce the hemicellulose content. Keywords: Cellulose, Napier grass fiber composition, Pretreatment Abstrak Komponen selulosa dalam rumput Napier mempunyai potensi yang tinggi untuk menghasilkan etanol. Kehadiran hemiselulosa, lignin dan selulosa dalam gentian rumput Napier boleh memberi kesan kepada penghasilan etanol. Objektif kajian ini adalah untuk menganalisa komposisi kimia rumput Napier dalam keadaan pra-rawatan yang berbeza (2% asid asetik dan 2% natrium hidroksida) dan untuk melihat pencirian gentian serat rumput Napier berdasarkan pra-rawatan yang berbeza. Morfologi permukaan gentian dilihat menggunakan Mikroskop Elektron Pengimbas. Keputusan analisa menunjukkan bahawa peratusan selulosa berdasarkan 2% rawatan asid asetik adalah paling tinggi, diikuti gentian yang dirawat dengan 2% natrium hidroksida dan sampel gentian yang tidak dirawat. Kandungan hemiselulosa berkurangan apabila dirawat dengan asid dan alkali. Berdasarkan pencirian morfologi, gentian rumput Napier yang dirawat dengan asid dan alkali mempunyai morfologi permukaan yang lebih licin dan mempunyai banyak ruang di antara gentian. Kajian ini mencadangkan bahawa rawatan asid dan alkali mempunyai potensi untuk menambahkan penghasilan etanol disebabkan berlakunya pengurangan kandungan hemiselulosa

Carboxymethyl-cellulase and filter-paperase activities of napier grass fermentation by new bacterial isolates

Cellulosic biomass is a renewable and most abundant resource with high potential for bioconversion to biofuels. It can be degraded by cellulase produced by cellulolytic producing bacteria. Proximately, three different types of cellulase needed for effective enzymatic hydrolysis; endoglucanase (CMCase), exocellobiohydrolase and β -glucosidase. Total cellulase activity can be determined by measuring reducing sugar derived from filter paper (FPase) while endoglucanase (CMCase) can be determined by measure reducing sugar release from carboxymethyl- cellulose (CMC). In this study, the CMCase and FPase activities of new six isolates from different environments (compost: C5/1 and C5/2; ponds: L5/1, L6/2, and L6/5; and decayed wood: D6/1) were examined according methods recommended by the International Union of Pure and Applied Chemistry (IUPAC).The fermentation has been conducted for 4 days incubation period at 37°C and agitated at 150 rpm. Napier grass has been used as a substrate. As a result, the C5/2 exhibited the highest enzymes activities of CMCase and FPase, which were 2.205U/mL and 0.39U/mL, respectively

Radical scavenging activity and phytochemical investigation of antioxidative compounds from stem and leaves of Leea indica species

In this paper, the potency of stem and leave extracts of Leea indica locally known as Memali from Tasik Chini, Pahang as a potent antioxidant agent had been studied. The antioxidant properties of three types of extracts was quantitatively assessed by 2,2 diphenyl-1- picrylhydrazyl ( DPPH) radical scavenging activity. The isolation of antioxidative compounds was conducted through preparative thin layer chromatography with the use of certain binary solvents. The structure determination was carried out using Gas Chromatography Mass Spectrometer (GCMS). The methanol extracts from both stem and leaf exhibited highest antioxidant activity with lowest IC50 of 1.14 ug/ml and 81 ug/ml respectively compared to other extracts. The stem showed stronger antioxidant activity compared to leaves part. Based on GCMS analysis, the antioxidative compounds isolated from leaves part were proposed as 6-Hyroxy-4,4, 7a-trimethyl-5,6,7,7atetrahydrobenzofuran-2(4H)-one (1), 3,8,8-Trimethoxy-3-piperidyl-2,2-binaphthalene1,1,4,4-tetrone (2), Methyl stearate (3), 9,12-Octadecadienoic acid (4), Palmitic acid (5) and 9-Oxononanoic acid (6). The antioxidative compounds isolated from stem part were determined as oleic acid (7), 1-(hydroxymethyl)-1,2- ethanediyl ester (8) and 9-octadecene (9). This finding can be used as scientific baseline information for the future treatment of diseases caused by harmful free radicals

Radical scavenging activity and phytochemical investigation of antioxidative compounds from stem and leaves of Leea indica species

In this paper, the potency of stem and leave extracts of Leea indica locally known as Memali from Tasik Chini, Pahang as a potent antioxidant agent had been studied. The antioxidant properties of three types of extracts was quantitatively assessed by 2,2 diphenyl-1-picrylhydrazyl ( DPPH) radical scavenging activity. The isolation of antioxidative compounds was conducted through preparative thin layer chromatography with the use of certain binary solvents. The structure determination was carried out using Gas Chromatography Mass Spectrometer (GCMS). The methanol extracts from both stem and leaves exhibited highest antioxidant activity with lowest IC50 of 24 ug/ml and 81 ug/ml respectively compared to other extracts. The stem showed stronger antioxidant activity compared to leaves part. Based on GCMS analysis, the antioxidative compounds isolated from leaves part were proposed as 6-Hyroxy-4,4, 7a-trimethyl-5,6,7,7a-tetrahydrobenzofuran-2(4H)-one (1), 3,8,8-Trimethoxy-3-piperidyl-2,2-binaphthalene-1,1,4,4-tetrone (2), Methyl stearate (3), 9,12-Octadecadienoic acid (4), Palmitic acid (5) and 9-Oxononanoic acid (6). The antioxidative compounds isolated from stem part were determined as 1- (hydroxymethyl)-1,2-ethanediyl ester (7), 9-octadecene (8) and oleic acid (9). This finding can be used as scientific baseline information for the future treatment of diseases caused by harmful free radicals