Measurement of Pigmentation by Methanol Extraction

Pigmented rice is considered as the good source of phytochemicals which contains more phenolic contents and higher antioxidant activities compared with non-pigmented rice. However, those phytochemicals are normally extracted using inorganic solvent, using water was rarely found. This study was aimed to compare extraction methods on antioxidant contents and activities of two types of Thai pigmented rice (black glutinous rice and red non-glutinous rice). Pigmented rice was extracted either conventional method alone or a combination of ultrasonic plus conventional method with different solvents (methanol and hot water). Phenolic contents were analyzed by spectrophotometric assay and high-performance liquid chromatography (HPLC). Antioxidant activities were investigated by radical scavenging capacity (ABTS and DPPH). The results showed that ultrasonic pretreatment significantly enhanced the total phenolic, flavonoid, anthocyanin contents and higher antioxidant activities compared with conventional extraction irrespective of solvents and rice varieties. Ultrasonic methanol (UM) extraction proved to extract significant higher content of all the compounds analyzed in both the rice varieties. In contrast, hot water (HW) extracts exhibited the lowest amount of bioactive compounds. However, there was no significant difference between methanol extraction alone and ultrasonic pretreatment with hot water extract on antioxidant contents for black glutinous rice. The contents of individual anthocyanins and flavonoids (cyanidin 3-O-glucoside, peonidin 3-O-glucoside, and quercetin) were significantly increased with ultrasonic pretreatment compare to the conventional method in black glutinous rice while failed to detect the red rice variety. The black glutinous rice contained significantly higher contents of all analyzed compounds and antioxidant activities than red rice. In conclusions, our results demonstrated that ultrasonic pretreatment significantly enhanced antioxidant extraction with higher activities compared with conventional extraction irrespective of solvents and rice varieties. Furthermore, the efficiency of ultrasonic together with hot water extraction was almost equal to methanol extraction which was the one effective solvent for extracting antioxidant.

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Intralesional injection of the methanol extraction residue of bacillus calmette-guerin (MER) into cutaneous metastases of malignant melanoma

Cancer ◽

10.1002/1097-0142(197812)42:6<2648::aid-cncr2820420621>3.0.co;2-j ◽

1978 ◽

Vol 42 (6) ◽

pp. 2648-2660 ◽

Cited By ~ 24

Author(s):

Susan E. Krown ◽

Elias Y. Hilal ◽

Carl M. Pinsky ◽

Yashar Hirshaut ◽

Harold J. Wanebo ◽

...

Keyword(s):

Malignant Melanoma ◽

Intralesional Injection ◽

Bacillus Calmette Guerin ◽

Cutaneous Metastases ◽

Methanol Extraction

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Detection of conjugated soy metabolites in urinary and tissue samples after methanol extraction

Journal of Food and Drug Analysis ◽

10.38212/2224-6614.2307 ◽

2020 ◽

Vol 17 (1) ◽

Author(s):

H.C. Chang ◽

J. Han ◽

R.L. Prior

Keyword(s):

Tissue Samples ◽

Methanol Extraction

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Multiresidue Method for the Determination of Triazine Herbicides in Field-Grown Agricultural Crops, Water, and Soils

Journal of AOAC INTERNATIONAL ◽

10.1093/jaoac/57.1.192 ◽

1974 ◽

Vol 57 (1) ◽

pp. 192-201 ◽

Cited By ~ 4

Author(s):

Klaus Ramsteiner ◽

Wolf D Hormann ◽

Dieter O Eberle

Keyword(s):

Agricultural Crops ◽

Triazine Herbicides ◽

Alumina Column ◽

Multiresidue Method ◽

Methanol Extraction

Abstract A gas chromatographic multiresidue method is described for the following triazine herbicides: ametryn, atraton, atrazine, desmetryn, metoprotryn, GS-13529, GS-14254, terbutryn, prometon, prometryn, propazine, and simazine. The method consists of a methanol extraction, cleanup on an alumina column, and determination on a Carbowax column with nitrogen-, sulfur-, and chloride-specific detectors. Extraction and recovery data are given.

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A Compact Extraction Apparatus for Use with the Semimicro Method for Determining Total Lipids in Fish Meal

Journal of AOAC INTERNATIONAL ◽

10.1093/jaoac/54.5.1132 ◽

1971 ◽

Vol 54 (5) ◽

pp. 1132-1134

Author(s):

Harry Miller ◽

George M Knobl

Keyword(s):

Extraction Method ◽

Fish Meal ◽

Total Lipids ◽

Methanol Extraction ◽

Extraction Apparatus ◽

Chloroform Methanol

Abstract A compact glass extraction apparatus has been designed for use with the semimicro chloroform-methanol extraction method for determining lipids in fish meal. No further handling is required after placing the sample in the extractor; this eliminates manipulative errors and makes the procedure more efficient. Results obtained with the use of this extractor agreed favorably with those from the semimicro method in which a blender was used and with results from AOAC 7.052. It is recommended that the method be studied collaboratively.

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