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ABSTRACT: Different proteins have been isolated from bovine milk including lactoferrin, lactoperoxidase, glycolactin, angiogenin-1, lactogenin, alpha-lactalbumin, lactoglobulin and casein. These proteins have been assayed for inhibitory activity against human immunodeficiency virus type 1 (HIV-1) reverse transcriptase, protease and integrase, enzymes crucial to the HIV-1 life cycle. It was found that different milk proteins inhibited the three aforementioned HIV enzymes to different extents. Lactoferrin strongly inhibited HIV-1 reverse transcriptase but only slightly inhibited HIV-1 protease and integrase. On the other hand, alpha-lactalbumin, beta-lactoglobulin and casein inhibited HIV-1 protease and integrase to an appreciable extent but did not inhibit HIV-1 reverse transcriptase. Glycolactin and angiogenin-1 suppressed the activity of HIV-1 reverse transcriptase by a moderate extent but more powerfully inhibited HIV-1 protease and integrase. In comparison with the other milk proteins glycolactin was a strong inhibitor of HIV-1 protease and integrase and a moderate inhibitor of HIV-1 reverse transcriptase. Lactogenin was a strong inhibitor of HIV-1 integrase, a moderate inhibitor of HIV-1 reverse transcriptase and a weak inhibitor of HIV-1 protease.
Life Sciences 10/2001; 69(19):2217-23. · 2.53 Impact Factor
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ABSTRACT: A trypsin inhibitor, MCCTI-1, with a molecular weight of 3479 Da as determined by mass spectrometry, was isolated from Momordica cochinchinensis seeds with a procedure involving extraction with 5% acetic acid, ammonium sulfate precipitation, ion exchange chromatography on CM-Sepharose and reverse-phase high performance liquid chromatography. The sequence of its first 13 N-terminal amino acid residues was ILKKCRRDSDCPG which was about 85% identical with the sequence of trypsin inhibitor MCTI-1 from Momordica charantia Linn. When compared with the sequences of most other squash family trypsin inhibitors, the sequence of MCCTI-1 was characterized by the deletion of a pentapeptide from the N-terminus. Trypsin inhibitors also existed in seeds of some hitherto uninvestigated Cucurbitaceae species.
The International Journal of Biochemistry & Cell Biology 07/1999; 31(6):707-15. · 4.63 Impact Factor
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ABSTRACT: An improved method for the removal of polyphenolic compounds from aqueous extracts of plants is presented. The method removes > 99% polyphenolic compounds from 5 mg of extract. The method is simple, robust and reproducible. We examined the removal of polyphenolics from 5 different aqueous extracts of Chinese medicinal herbs.
Biochemistry and molecular biology international 07/1998; 45(4):791-6.
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ABSTRACT: A microplate assay, for use with a variety of glycohydrolase enzymes, was developed to aid the screening of Chinese medicinal herb extracts for the presence of potential anti-viral and anti-lymphoma compounds. The microplate assay method described offers greater convenience, speed and reproducibility over existing methods. The enzymes tested were alpha-glucosidase, beta-glucosidase and beta-glucuronidase. The assay can be easily adapted for use with other glycohydrolase enzymes. Of the 12 herb extracts examined four did not inhibit any of the enzymes (< 50% inhibition), one inhibited alpha-glucosidase only (> 50% inhibition), six inhibited beta-glucuronidase only, and one inhibited both alpha-glucosidase and beta-glucuronidase. None of the extracts were capable of inhibiting beta-glucosidase to any significant extent.
Biochemistry and molecular biology international 09/1997; 42(6):1163-9.
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ABSTRACT: A multiple screening approach to detect compounds inhibitory to various aspects of the human immunodeficiency virus type 1 (HIV-1) life-cycle has been applied to aqueous extracts of 19 herbs traditionally used in Chinese medicine as anti-viral agents. The extracts were tested for their ability to inhibit HIV-1 in a series of in vitro assays. The extracts were tested for inhibition of the interaction between HIV-1 gp120 and immobilized CD4 receptor, inhibition of recombinant HIV-1 reverse transcriptase and for inhibition of three glycohydrolase enzymes that contribute to viral protein glycosylation. Six of the herb extracts (30%) were potent inhibitors of the interaction between HIV-1 gp120 and the CD4 receptor (ID50 5.6 - 79.4 microg/ml), two extracts (10%) contained potent reverse transcriptase inhibitors (ID50 16.9 - 26.0 microg/ml) and 14 extracts (75%) were able to inhibit at least one of the glycohydrolase enzymes.
Life Sciences 02/1997; 60(23):PL345-51. · 2.53 Impact Factor
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ABSTRACT: Different proteins have been isolated from bovine milk including lactoferrin, lactoperoxidase, glycolactin, angiogenin-1, lactogenin, α-lactalbumin, lactoglobulin and casein. These proteins have been assayed for inhibitory activity against human immunodeficiency virus type 1 (HIV-1) reverse transcriptase, protease and integrase, enzymes crucial to the HIV-1 life cycle. It was found that different milk proteins inhibited the three aforementioned HIV enzymes to different extents. Lactoferrin strongly inhibited HIV-1 reverse transcriptase but only slightly inhibited HIV-1 protease and integrase. On the other hand, α-lactalbumin, β-lactoglobulin and casein inhibited HIV-1 protease and integrase to an appreciable extent but did not inhibit HIV-1 reverse transcriptase. Glycolactin and angiogenin-1 suppressed the activity of HIV-1 reverse transcriptase by a moderate extent but more powerfully inhibited HIV-1 protease and integrase. In comparison with the other milk proteins glycolactin was a strong inhibitor of HIV-1 protease and integrase and a moderate inhibitor of HIV-1 reverse transcriptase. Lactogenin was a strong inhibitor of HIV-1 integrase, a moderate inhibitor of HIV-1 reverse transcriptase and a weak inhibitor of HIV-1 protease.
Life Sciences.
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[show abstract]
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ABSTRACT: A multiple screening approach to detect compounds inhibitory to various aspects of the human immunodeficiency virus type 1 (HIV-1) life-cycle has been applied to aqueous extracts of 19 herbs traditionally used in Chinese medicine as anti-viral agents. The extracts were tested for their ability to inhibit HIV-1 in a series of in vitro assays. The extracts were tested for inhibition of the interaction between HIV-1 gp 120 and immobilized CD4 receptor, inhibition of recombinant HIV-1 reverse transcriptase and for inhibition of three glycohydrolase enzymes that contribute to viral protein glycosylation. Six of the herb extracts (30%) were potent inhibitors of the interaction between HIV-1 gp 120 and the CD4 receptor (ID50 5.6–79.4 μg/ml), two extracts (10%) contained potent reverse transcriptase inhibitors (ID5016.9–26.0 μg/ml) and 14 extracts (75%) were able to inhibit at least one of the glycohydrolase enzymes.
Life Sciences.
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ABSTRACT: A new ribosome-inactivating protein (RIP) (δ-momorcharin) and a candidate RIP (ε-momorcharin) were isolated, respectively, from the seeds and fruits of the bitter gourd Momordica charantia, by affinity chromatography on Affi-gel blue gel and ion exchange chromatography on Mono S with a fast protein liquid chromatography (FPLC) system. Both δ- and ε-momorcharins were adsorbed on Affi-gel blue gel and were eluted from the cation exchange Mono S column earlier than α- and β-momorcharins, the two previously reported RIPs, δ- and ε-momorcharins possessed a molecular weight of 30 and 24 kDa respectively and inhibited cell-free translation in rabbit reticulocyte lysate with an IC50 of 0.15 and 170 nM. The sequence of the first seven N-terminal amino acids in δ-momorcharin was DVNFGLA, which was different from the N-terminal sequences DVSFRLS and DVNFDLS for α- and β-momorcharins respectively.
The International Journal of Biochemistry & Cell Biology.