Limonda hasat sonrası hastalık etmeni olan Alternaria alternata LS1'E karşı Yarrowia lipolytica ve bor ürünlerinin antifungal etkileri
Antifungal effects of Yarrowia lipolytica and boron compounds against Alternaria alternata LS1 a post-harvest di̇sease agent in lemons
- Tez No: 1018504
- Danışmanlar: PROF. DR. SUZAN ÖZTÜRK YILMAZ
- Tez Türü: Yüksek Lisans
- Konular: Gıda Mühendisliği, Food Engineering
- Anahtar Kelimeler: Biyolojik kontrol, Maya, Antifungal, Limon, Antagonist, Bor, Biological control, Yeast, Antifungal, Lemon, Antagonist, Boron
- Yıl: 2026
- Dil: Türkçe
- Üniversite: Sakarya Üniversitesi
- Enstitü: Fen Bilimleri Enstitüsü
- Ana Bilim Dalı: Gıda Mühendisliği Ana Bilim Dalı
- Bilim Dalı: Belirtilmemiş.
- Sayfa Sayısı: Belirtilmemiş.
Özet
Meyve ve sebzelerde hasat sonrası depolama sürecinde ürün kayıplarına sebep olan fungal hastalıkların kontrolünde, fungusitlere alternatif olabilecek yeni biyolojik mücadele yöntemlerinin geliştirilmesi amacıyla yapılan bu çalışmada, turunçgil ve limonlarda çürüme ve yanıklık hastalıkları etmeni olan Alternaria alternata LS1 suşuna karşı Yarrowia lipolytica Y45 suşu ve bor ürünlerinin antifungal etkileri in vitro ve in vivo koşullarda araştırılmıştır. Bu amaçla in vitro koşullarda Y. lipolytica Y45'in antagonist özellikleri analiz edilmiş; bor ürünlerinin tek başına ve maya ile kombinasyon halinde uygulanmasının antifungal etkileri incelenmiştir. Bu uygulamaların in vivo koşullarda meyve üzerinde A. alternata LS1 kaynaklı hastalık kontrolü ve doğal çürüme üzerine etkileri değerlendirilmiştir. Y. lipolytica Y45 suşu A. alternata LS1 suşunun gelişimini ikili kültür denemesinde %76,87 oranında inhibe etmiştir. A. alternata LS1'e karşı maya suşunun ürettiği uçucu organik bileşikler %75,64; maya içermeyen süpernatant ise %69,69 inhibisyon etkisi göstermiştir. Maya suşunun A. alternata LS1 ile direkt temas halinde inhibisyon etkisi %78,18 oranında ölçülmüştür. Elde edilen sonuçlar doğrultusunda, Y. lipolytica Y45 suşunun A. alternata LS1 suşuna karşı besin ve alan konusunda başarılı bir şekilde rekabet ettiği ve direkt parazitizm yoluyla inhibisyon sağladığı söylenebilir. Bunun yanında uçucu olan ve uçucu olmayan metabolitler üreterek antagonist etki gösterdiğini de söylemek mümkündür. 0, 10 ve 30 g FeCl₃/ml içeren ortamlarda maya suşunun misel gelişimi engelleme oranları birbirine yakın olup sırasıyla %76,87; %70,95 ve %70,98 olarak ölçülmüştür. Bu durumda demir rekabetinin antagonist aktivite üzerinde önemli bir etkisinin olmadığı tespit edilmiştir. Borik asit ve boraks dekahidratın antifungal etkisi konsantrasyonla doğru orantılı olarak artış göstermiştir. Borik asit %3,0 ve boraks %2,0 kosantrasyonlarda sırasıyla %96,61 ve %90,06 inhibisyon etkisi göstererek patojen gelişimini neredeyse tamamen inhibe etmiştir. Maya suşunun %0,125 borik asit ve %0,125 boraks ile birlikte kullanımında sırasıyla %70,72 ve %66,49 oranında inhibisyon etkisi görülmüş olup; maya suşunun tek başına uygulandığı testlerde patojenin misel gelişimini engelleme oranı daha yüksek bulunmuştur. İn vivo koşullarda koruyucu etkinliği en fazla olan uygulama maya uygulaması olup %98,39 etki göstermiştir. Yapılan tüm uygulamalar doğal çürümenin kontrolünde etkili olurken en etkili sonuç (%99,86) maya uygulaması sonucunda alınmıştır. İn vivo koşullarda yapılan analizlerde elde edilen başarılı sonuçların, maya suşunun patojenüzerindeki antagonistik etkilerinin yanında, meyvede doğal bağışıklık enzimlerinin üretimini tetiklemesinden kaynaklandığı düşünülmektedir. xx Elde edilen sonuçlar, Y. lipolytica Y45 suşu ve bor ürünlerinin limon meyvesinde A. alternata LS1 kaynaklı hastalık ile mücadelede sentetik fungusitlere alternatif olarak etkili bir şekilde kullanılabileceğini göstermektedir.
Özet (Çeviri)
Fruits and vegetables are an essential food group for a healthy and balanced diet. These foods are very important for our health because they contain essential vitamins and minerals for the human body and have high antioxidant capacities due to their polyphenolic compounds. Citrus fruits constitute a group of fruits known for their distinctive smell and aroma, rich in vitamin C and bioactive compounds. In the Rutaceae family, citrus fruits belonging to the Citrus genus of the Aurantioideae subfamily include species such as orange, tangerine, lemon, pomelo, grapefruit, and citron. Lemon (Citrus limonia (L.) Burm. f.); is a citrus fruit widely cultivated worldwide and in Turkey. It is known for its high vitamin C content and its distinctive taste and aroma. Its antioxidant and bioactive properties are due to its content of vitamin C, carotenoids, and phenolic compounds. In the world and in our country, post-harvest losses of fresh fruits and vegetables cause serious economic damage. These diseases, which occur during the harvesting, packaging, transportation and storage of products, are increasing due to a lack of knowledge or care in harvesting practices and inadequate storage conditions. It is known that such product losses reach %25-30 annually in our country. As the global population rapidly increased, the demand for agricultural products also grew. At the same time, the reduction in agricultural land led to food shortages. In this situation, reducing losses in harvested products became as important as increasing efficiency in agricultural production. The vast majority of post-harvest diseases are caused by fungi. The common practice for controlling these types of diseases is the use of synthetic fungicides. Its ease of application and maintenance, as well as its ability to produce rapid results, have made the use of fungicides preferable. However, in the long term, its use becomes more difficult due to reasons such as environmental harm, residuals on food products, and the increased resistance of target microorganisms. For these reasons and also due to the increasing tendency of consumers to prefer more natural and additive-free products over time, there has been a need to apply more diverse methods in the fight against post-harvest fungal diseases in fruits and vegetables. In this context, environmentally and economically friendly biocontrol methods with high efficiency, toxicological safety, and low residue rates are seen as good alternatives. Antagonism can be defined as one of two microorganisms in an environment harming the other directly or indirectly, hindering its vital activities and development. In biological control, by utilizing this approach, the presence and development of pathogenic microorganisms are inhibited by the antagonistic effect of non-toxic or xxi beneficial microorganisms. In the biological control of post-harvest diseases in fruits and vegetables, yeasts, lactic acid bacteria, Gram-positive and Gram-negative bacteria, and molds can be used as antagonists. In this study, conducted to develop biological defence methods that could serve as alternatives to fungicides for the control of fungal diseases causing postharvest losses during stocking period, in fruits and vegetables, the antifungal effects of Yarrowia lipolytica Y45 and boron products against Alternaria alternata LS1, the causal agent of rot and blight diseases in citrus fruits and lemons, were investigated under in vitro and in vivo conditions. For this purpose, the pathogenic fungus isolated from diseased lemon fruits was purified using the single spore drop technique on PDA. The pathogenicity of the fungus was tested and confirmed on healthy lemon fruits. The pathogenic fungus was diagnosed using molecular methods as a service purchase and identified as A. alternata. The identified fungus was named A. alternata LS1 and maintained under laboratory conditions for use in subsequent studies. Under the in vitro analyses, which constitute the first phase of the study, the antagonist activities of the yeast strain against A. alternata LS1 were investigated. First, a dual culture assay was performed to measure nutrient and space competition between the two cultures. A inhibition percentage analysis was conducted to evaluate the interrelated interactions of the two cultures. A volatile antibiotic test was conducted to measure the ability of the yeast cell to produce volatile antibiotics; an analysis was performed with yeast filtrate to measure its capacity to produce non-volatile antibiotics. The effects of different iron concentrations on the antagonistic activity of the yeast strain were tested by adding 0, 10 and 30 g FeCl₃/ml to PDA medium. To investigate the antifungal effects of bor products on A. alternata LS1, boric acid and borax decahydrate were added to PDA medium at nine different concentrations ranging from 0,0312% to 4,0% w/v. The antifungal effects of increasing concentrations of boric acid and borax were evaluated by inoculating petri dishes with pathogens. To investigate the effects of boron compounds on the antagonistic activity of Y. lipolytica Y45 against A. altenata LS1, boron concentrations that Y. lipolytica Y45 was initially insensitive to were identified. For this purpose, the diffusion method was used, and the highest concentration that did not inhibit the growth of the yeast strain for boric acid and borax was found to be 0.125 w/v%. In this regard, a dual culture analysis of Y. lipolytica Y45 and A. alternata LS1 was performed on PDA media supplemented with 0,125% w/v boric acid and borax decahydrate. In the scope of in vivo analyses, the protective effects of using borate products and Y. lipolytica Y45 separately and in combination for controlling A. alternata LS1-induced disease on lemon fruit were evaluated. For this purpose, healthy, sterilized lemon fruits were wounded and treated with the selected treatment; subsequently, they were inoculated with A. alternata LS1. After 21 days of storage at 25°C and 65% humidity, the development of lesions around the wounds was measured and compared with the control group. xxii To determine the effect of the applied treatment parameters on the natural decay tendency of lemon fruit during storage under the same conditions, sterile lemon fruits were treated by dipping with the specified treatments. At the end of storage, the formation of lesions on the fruits was checked. According to the results obtained, A. alternata LS1 yeast strain Y. lipolytica Y45 used at a concentration of 1x10⁸ cells/ml inhibited mycelial growth by 76,87% in the dual culture assay. The inhibition rate of volatile organic compounds produced by the Y. lipolytica Y45 strain was found to be 75,64%; the inhibition rate of the supernatant not containing yeast cells was 69,69%. When the Y. lipolytica Y45 strain was in direct contact with the pathogen, the inhibition was determined to be 78,18%. No statistically significant difference was found between the antagonistic activities. In light of these results, it has been demonstrated that the yeast strain is capable of successfully competing with the pathogen for nutrients and space. Furthermore, it can also be said that it exhibits antifungal properties by producing volatile and non-volatile antibiotics. It was determined that different iron concentrations used in the study did not affect the antagonistic activity between the two cultures. As the concentrations of boric acid and borax decahydrate increased in the growth medium, their antifungal effects also grew. Boric acid at a concentration of 3,0% and borax at 2,0% respectively exhibited inhibition effects of 96,61% and 90,05% against A. alternata LS1, nearly completely inhibiting the development of the pathogen. The inhibition rates resulting from the use of the yeast strain with 0,125% boric acid and 0,125% borax were measured as 70,72% and 66,49%, respectively. The use of the yeast strain in combination with boron products did not exhibit the anticipated effect of increasing antagonist activity. Among the treatments applied under in vivo conditions, the highest protective activity against the development of A. alternata LS1induced disease in lemon fruit was the yeast application, which showed an efficacy of 98,39%. While treatments with boric acid and borax were respectively 51,85% and 46,88% effective, the use of boric acid and borax in conjunction with yeast was respectively 80,18% and 67,96% effective. Regarding the natural tendency of fruit to rot, the most effective treatment among all applied treatments is the yeast application, which has shown an efficacy rate of 99,86%. While boric acid and yeast treatments were respectively 39,25% and 43,65% effective, the use of boric acid and borax together with yeast was respectively 99,50% and 98,86% effective. The successful results obtained in in vivo analyses were attributed to the antagonistic effects of yeast extract on the pathogen, as well as its ability to trigger the production of natural decomposition enzymes in the fruits. Contrary to popular opinionthe use of boric acid and borax did not show a stimulatory effect on the antagonistic activity of the antagonist yeast. The results obtained indicate that Y. lipolytica Y45 and boron products can be effectively used as an alternative to synthetic fungicides in controlling A. alternata LS1-induced disease in lemon fruit. It is thought that more successful results can be obtained by using the applied practices in combination with different antagonist xxiii microorganisms or processes, or by conducting trials with different concentrations of these practices, in order to make their effects more stable and controllable.
Benzer Tezler
- Adana ili, turunçgil toptan fiyatlarının analizi
Başlık çevirisi yok
USULET ÖZTUNÇ
Yüksek Lisans
Türkçe
1987
ZiraatÇukurova ÜniversitesiTarım Ekonomisi Ana Bilim Dalı
DOÇ. DR. OĞUZ YURDAKUL
- Alexandria Troas antik kenti limanı ve liman yapıları
Başlık çevirisi yok
HARUN ÖZDAŞ
Yüksek Lisans
Türkçe
1991
ArkeolojiHacettepe ÜniversitesiArkeoloji ve Sanat Tarihi Ana Bilim Dalı
DOÇ. DR. ENGİN ÖZGEN
- Gantry kreynli konteyner gemilerinin boyuna mukavemeti
Longitudinal strength of ships with gantry crane
BÜLENT ERDEM