Аннотация

Галактоолигосахариды обладают пребиотической активностью, их получают из лактозы с использованием бета-галактозидаз бактериального или грибного происхождения. Цель обзора – выявление и анализ факторов, влияющих на биосинтез и очистку галактоолигосахаридов, с использованием бета-галактозидаз дрожжей рода Kluyveromyces, а также перспективных направлений исследований в этой области. Объектами исследования стали научные публикации по вопросам получения галактоолигосахаридов с использованием бета-галактозидаз дрожжей. Для поиска информации были использованы международные базы данных Scopus, Web of Science, PubMed, eLIBRARY.RU Для анализа было отобрано 87 источников, в основном статьи в рецензируемых журналах, опубликованные преимущественно за последние 10 лет. Выбор фермента и формы его применения, оптимизация условий биосинтеза и очистки являются наиболее важными для регулирования выхода, состава и свойств анализируемых веществ. Бета-галактозидазы из Kluyveromyces могут одновременно катализировать реакции гидролиза и трансгалактозилирования. Условия протекания процессов биосинтеза галактоолигосахаридов с этими ферментами широко варьируют в разных публикациях, как и их выход, но чаще всего этот показатель не превышает 30–40 %, при этом общая конверсия лактозы достигает 80–90 %. Применение бета-галактозидаз Kluyveromyces в виде цельноклеточных ферментов, в иммобилизованной форме или совместно с другими ферментами позволяет улучшить экономические показатели процессов биосинтеза и / или выход и / или структуру рассматриваемых веществ. Прямой их синтез в молоке или сыворотке дает возможность получать новые функциональные молочные продукты и добавки. Селективная биоконверсия с дрожжами Kluyveromyces позволяет повысить чистоту галактоолигосахаридов до 90 % экономически выгодным и экологически безопасным путем. К перспективным направлениям можно отнести использование побочного молочного сырья для получения продуктов с галактоолигосахаридами, комбинированное применение ферментов разных продуцентов, а также комплексное применение бета-галактозидаз Kluyveromyces для их биосинтеза и очистки.

Ключевые слова

Лактоза, бета-галактозидазы, Kluyveromyces, трансгалактозилирование, гидролиз, молочная сыворотка, очистка

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