Influence of different extraction solvents on antioxidant and antityrosinase activities of Morus alba Linn. leaf extract.

Wachira Yodthong, Suraphon Chaiwongsar, Penpicha Wanachantararak, Yanee Keereeta, Watee Panthuwat, Benjaporn Saovapha, Tanongsak Sassa-deepaeng*

J. Sci. Agri. Technol. (2020) Vol. 1 (1): 7-17

Abstract

The objective of this study was to investigate the impact of different extraction solvents such as hexane, benzene, ethyl acetate, acetone, ethanol, and water on antioxidant and antityrosinase efficiency of mulberry leaf extract. The sample was extracted from leaves by maceration method. The obtained extract was filtered and evaporated to dryness by using the rotary evaporator prior to measuring the total phenolic content, flavonoid content, antioxidant activity, antityrosinase activity, and morin content in triplicate. The results indicated that the highest antioxidant activity was found in ethyl acetate (EA) fraction of CM60 with ABTS value of 57.8 ± 7.7 % inhibition and DPPH value of 58.2 ± 0.7 % inhibition that were positively related to its phenolic content (36.9 ± 1.3 mg GAE/mg DW). Interestingly, The highest antityrosinase activity was found in acetone fraction of CM60 which inhibited tyrosinase activity by 3.0 ± 0.1 mg KE/mg DW that was positively related to its flavonoid content (32.71 ± 0.1 mg QE/mg DW) and was related to its highest morin content (0.71 ± 0.01 mg/mg DW) measured using HPLC. The present results indicated that the EA fraction of CM60 possessed the highest antioxidant property related to its phenolic content, and the acetone fraction showed the highest antityrosinase activity related to its flavonoid content especially morin which is tyrosinase inhibitor. Both fractions of M. alba were potential candidates for skin protector from oxidative damage and skin-whitening agent development. Further studies are necessary to formulate the compounds responsible for antioxidant and antityrosinase properties and to investigate antityrosinase properties in vivo prior to transferring technology to communities.

Keywords: mulberry, antioxidant, antityrosinase, solvent extraction

Received January 21, 2020. Revised February 9, 2020; March 23, 2020. Accepted March 23, 2020.


Characteristics of yogurt supplemented with different concentrations of Carissa carandas L.

Ni-orn Chomsri* and Kamonwan Manowan

J. Sci. Agri. Technol. (2020) Vol. 1 (1): 18-25

Abstract

Yogurt is a fermented dairy product claimed to confer health benefits due to the remaining viability of good lactic acid bacteria (LAB). This study investigates the influence of using Carissa carandas L. (CC) as a supplement in the yogurt. The yogurt samples were examined for their physicochemical, microbiological and sensory properties. Supplementation of CC berry in the yogurt improved the quality compared with 0% supplementation of CC berry. Yogurt with 20% CC berry exhibited the highest total phenolic compounds. LAB present in yogurt was remained above 8 log CFU/g after 21 day storage period at 4 oC. Yogurt with CC berry supplements showed better sensory properties (moderately like to like very much) than yogurt without CC berry supplement (p≤0.05). The finding of this study suggests that CC berry is a potential plant-based component to improve both phytochemical and sensory properties in yogurt production.

Keywords: Carissa carandas, yogurt, lactic acid bacteria, phytochemicals

Received December 19, 2019. Revised February 9, 2020; March 22, 2020. Accepted March 22, 2020.


Coconut and to a lesser extent krabok oil, depress rumen protozoa in beef cows

Paiwan Panyakaew*, Jan Thomas Schonewille, Veerle Fievez, Gunjan Goel, Nico Boon, Chalermpon Yuangklang, Wouter Hendriks

J. Sci. Agri. Technol. (2020) Vol. 1 (1): 26-32

Abstract

Krabok and coconut oil were assessed for their ability to affect rumen protozoa via a 3×3 Latin square design with three rumen cannulated beef cows. The diets consisted of a TMR supplemented with either 25.5 g/kg of tallow (control) or the same quantity of coconut oil or krabok oil. The animals were fed restricted amounts (DM) of the experimental rations (1.5% of body weight per d) for 28 d per period. The samples of rumen fluid were collected on day 23 and 27 of each period, 0, 3, 6, 9 and 12h after morning feeding. Protozoa numbers decreased by 0.33 log units in the coconut (P<0.05) and 0.21 log units in the krabok oil diet (P<0.05) compared with the control diet. The ciliate value was not significantly different between treatment but were strongly (R2 = 0.88) linearly associated with protozoa counts. The concentration of total VFA was not affected (P = 0.804) by the diet. Except propionic acid which showed a trend (P = 0.056), the proportions of the remaining VFA were not significantly (P>0.10) different between treatments. The propionate proportion was only reduced by supplementation of coconut oil to the TMR. Neither oils affected amylolytic, cellulolytic or proteolytic bacteria counts. Cluster analysis of the DGGE profile showed two clusters of ciliate communities, one including all the T diet-fed animals. All except one DGGE profile of a cow fed the KO diet group into the second cluster. Coconut oil, and to a lesser extent krabok oil, has a marked effect on the numbers of rumen protozoa.

Keywords: krabok oil, coconut oil, rumen protozoa, ciliate

Received January 25, 2020. Revised March 3, 2020; March 12, 2020. Accepted March 22, 2020.


Preparation of activated carbon as support of nickel catalyst for Guerbet reaction

Krittanun Deekamwong, Supunnee Junpirom and Jatuporn Wittayakun* 

J. Sci. Agri. Technol. (2020) Vol. 1 (1): 33-39

Abstract

This work aims to prepare activated carbon from charcoal from the wood of Muntingia calabura Linn. and employ as support for nickel catalyst. The charcoal was obtained from an Iwasaki kiln and activated by CO2. Then, the surface of activated carbon was modified by air zero to create acid functional groups. The polyaromatic-like structure and functional groups of the activated carbon were characterized by Fourier transform infrared spectroscopy (FTIR) and elemental analysis. The thermal stability was carried out by thermogravimetric analysis (TGA). The surface areas of the samples were determined by Brunauer–Emmett–Teller (BET) from N2 adsorption-desorption analysis. The activated carbon after modification had higher acid functional groups than the parent charcoal. The BET surface area decreased after modification, but the thermal stability did not change after CO2 treatment. After impregnated with nickel precursor, the phases of the catalyst were analyzed by X-ray diffraction (XRD). Nickel nanoparticles were produced on activated carbon. The catalytic screening of Guerbet reaction to produce n-butanol from ethanol conversion was performed under autogeneous pressure at 240 °C for 6 h. The nickel supported on activated carbon showed higher ethanol conversion than the unsupported nickel nanoparticles.

Keywords: Muntingia calabura Linn.; activated carbon; nickel nanoparticles, catalyst, guerbet reaction

Received January 22, 2020. Revised March 27, 2020. Accepted March 29, 2020.

 


The cloning of the MPER1 and PX3 peroxidase genes conferring bacterial blight disease resistance genes in cassava (Manihot esculenta (L.) Crantz)

Payungsak Rauyaree*,  Paranee Sawangsri, and Suphawadee Ngorian

J. Sci. Agri. Technol. (2020) Vol. 1 (1): 1-6

Abstract

Cassava bacterial blight, CBB caused by Xanthomonas ampestris pv. manihotis pv. Manihotis is an important outbreak of cassava bacterial disease in Thailand. Plant peroxidases play major roles in many physiology processes both abiotic and biotic stress including plant defense response against a bacterial pathogen. The objective of this research was to clone the peroxidase genes homologs in cassava variety Rayong 60 (MTAI 8), which is a disease-resistant variety against cassava bacterial blight by using polymerase chain reaction method. According to our results, two peroxidase genes homolog named MPER1 (cationic peroxidase; GenBank Accession No. EF645823) and PX3 (secretory peroxidase; GenBank Accession No. EF645824) in cassava MTAI8 genome were isolated and determined. The MPER1 contains 1,211 nucleotide 2 exons and 1 intron with 73% similarity to the peroxidase gene in Arabidopsis thaliana which was the first plant to have its genome sequenced, and is a popular tool for understanding the molecular biology of many plant traits. The PX3 contains 945 nucleotides 3 exons and 3 introns with 57% high similarity to peroxidase gene in Arabidopsis thaliana. The predicted amino acid sequence revealed a 98 and 134-amino acid for MPER1 and PX3, respectively. Both of the genes showed conserved a domain of peroxidase genes (gene superfamilies) with other plant species. These genes will be useful as a molecular marker in selecting disease-resistant varieties and for further used as plant genetic improvement approach.

Keywords: cassava bacterial blight, CBB, MPER1, PX3

Received November 26, 2019. Revised January 21, 2020; March 18 2020. Accepted March 22, 2020.