Isolation, purification, and characterization of pectin methylesterase inhibitor and polygalacturonase inhibitor protein from Indian lemon (Citrus limon L.)

Cloud stabilization of citrus fruit juices treated with purified pectin methylesterase inhibitor from lemon (Citrus limonL.)

“…Purified lemon PMEI demonstrated a specific activity of 5150 U mg −1 protein and 89.13‐fold purification (data not shown) 7 . PMEI from kiwi fruit was purified with 56.1% yield and 20.8‐fold purity using Sepharose 12 resin 5 .…”

“…PMEI extraction and purification from lemon were performed as reported by Bakshi and Ananthanarayan 7 . PMEI was extracted by homogenizing the fruit pulp in distilled water (pH 6, 1:1, w/v).…”

“…PMEI extraction and purification from lemon were performed as reported by Bakshi and Ananthanarayan. 7 PMEI was extracted by homogenizing the fruit pulp in distilled water (pH 6, 1:1, w/v). The resulting crude extract was subjected to ammonium sulfate precipitation and the fraction saturating between 25-75% was further dialyzed with 20 mmol L −1 Tris buffer, pH 8.5.…”

“…Many molecules inhibit PME activity but the best described and widely studied so far is the proteinaceous pectin methylesterase inhibitor (PMEI) found in kiwi fruit, which inhibits PME activity from plant sources such as cucumber, orange, tomato, kiwi, banana, apricot, and potato 5,6 . Apart from kiwi fruit, PMEI and PMEI genes have been identified in various plant sources 7 . Very few studies have reported the use of PMEI to stabilize the cloud of citrus juices.…”

“…5,6 Apart from kiwi fruit, PMEI and PMEI genes have been identified in various plant sources. 7 Very few studies have reported the use of PMEI to stabilize the cloud of citrus juices. Kiwi fruit PMEI has been employed to obtain cloud-stable orange juice concentrates.…”