Postharvest diseases of potato lead to significant food and economic losses worldwide. The exogenous application of eco-friendly methods plays an important role in the control of postharvest decay. In this work the effects of endophytic bacteria B. subtilis (10-4, 26D) were studied in the context of two application parameters: concentration, with a range between 10³–10⁸ CFU/mL tested, and synergistic effects of the signal molecule salicylic acid (SA) (0.05 mM) on potato tubers’ resistance to Phytophthora infestans and Fusarium oxysporum during storage. The experiments were carried out on hydroponically grown potato (Solanum tuberosum L.) mini-tubers. This study demonstrates the suppressive effect of B. subtilis (10-4, 26D) on diseases of potato during storage and reveals that this effect happens in a dose-dependent manner, both individually and in combination with SA. The most effective concentrations of B. subtilis for suppression of both Ph. infestans and F. oxysporum are 10⁸ CFU/mL (10-4 and 26D), 10⁷ CFU/mL (10-4 + SA) and 10⁶ CFU/mL (26D + SA). The ability of B. subtilis (10-4, 26D) to effectively penetrate and colonize the internal tubers’ tissues when applied immediately prior to storage, and the ability of SA to accelerate these processes, have been proven. B. subtilis (10-4, 26D), individually and in compositions with SA, increased ascorbic acid content and decreased pathogen-induced proline accumulation and lipid peroxidation in tubers. This indicates a protective effect conferred to cells against reactive oxygen and an extension of aging processes, manifested by a prolonged shelf life and extended preservation of fresh appearance.

Potato (Solanum tuberosum L.) tubers are a highly important food crop in many countries due to their nutritional value and health-promoting properties. Postharvest disease caused by Phytophthora infestans leads to the significant decay of stored potatoes. The main objective of this study was to evaluate the effects of the endophytic bacteria, Bacillus subtilis (strain 10–4), or its combination with salicylic acid (SA), on some resistance and quality traits of stored Ph. infestans-infected potato tubers. The experiments were conducted using hydroponically grown potato mini-tubers, infected prior to storage with Ph. infestans, and then coated with B. subtilis, alone and in combination with SA, which were then stored for six months. The results revealed that infection with Ph. infestans significantly increased tuber late blight incidence (up to 90–100%) and oxidative and osmotic damage (i.e., malondialdehyde and proline) in tubers. These phenomena were accompanied by a decrease in starch, reducing sugars (RS), and total dry matter (TDM) contents and an increase in amylase (AMY) activity. Moreover, total glycoalkaloids (GA) (α-solanine, α-chaconine) notably increased in infected tubers, exceeding (by 1.6 times) permissible safe levels (200 mg/kg FW). Treatments with B. subtilis or its combination with SA decreased Ph. infestans-activated tuber late blight incidence (by 30–40%) and reduced oxidative and osmotic damages (i.e., malondialdehyde and proline) and AMY activity in stored, infected tubers. Additionally, these treatments decreased pathogen-activated GA accumulation and increased ascorbic acid in stored tubers. Thus, the results indicated that endophytic bacteria B. subtilis, individually, and especially in combination with SA, have the potential to increase potato postharvest resistance to late blight and improve tuber quality in long-term storage.

The effect of endophytic Bacillus subtilis (strains 10-4, 26D) and their compositions with salicylic acid (SA) on some resistance and quality traits of stored potatoes infected with Fusarium dry rot were studied. The experiments were carried out on hydroponically grown Solanum tuberosum L. tubers that were infected before storage with Fusarium oxysporum and coated with B. subtilis 10-4, 26D with and without exogenous SA, and then stored for six months. It has been shown that 10-4, 26D, 10-4 + SA, and 26D + SA reduced in different levels (up to 30–50%) the incidence of F. oxysporum-caused dry rot (with the highest effect for 10-4 + SA). SA notably enhanced the positive effect of 10-4, while for 26D, such an effect was not observed. All of the tested treatments increased amylase (AMY) and AMY inhibitors activity in infected tubers, while decreased Fusarium-induced protease activity (except in the case of 10-4 + SA, which promoted a slight increase) was revealed. 10-4, 26D, and their compositions with SA decreased (in different degrees) the pathogen-caused lipid peroxidation, proline, and reducing sugars accumulation in potatoes after long-term storage. It was also discovered 10-4 and 26D, regardless of SA presence, decrease pathogen-induced glycoalkaloids α-Solanine and α-Chaconine accumulation and preserved increased levels of starch and total dry matter in infected stored potatoes. The findings indicate endophytic B. subtilis and its compositions with SA is a promising eco-friendly and bio-safe approach to cope with postharvest decays of potato during long-term storage; however, when developing preparations-compositions it should take into account the strain-dependent manner of B. subtilis action together with SA.

The effect of addition commercial fish collagen hydrolysate and encapsulated fish collagen hydrolysate on the quality characteristics of sucuk (a traditional Turkish dry-fermented sausage) was investigated. Fish collagen hydrolysates were encapsulated with maltodextrin (MD) which has two different dextrose equivalent (12DE and 19 DE), with two different types of core/coating material ratios (10% peptide : 90% MD, 20% peptide : 80% MD). Than six group of sucuk dough (control, peptide, MD1210, MD1220, MD1910, MD1920) prepared and naturally fermented. The effects of the ripening period (28 d), treatment (peptide and encapsulated peptide addition) 'ripening period × treatment' interaction on sucuk's pH, lactic acid contents, a_w values and moisture contents were statistically significant (p<0.01). The pH, moisture and a_w decrease and lactic acid concentration increses during ripening period. The highest pH was observed with peptide added group (5.41), and encapsulated peptide added groups (4.76-4.77) were lower than the control group (5.26). Lactic acid concentration was affected from treatment and all treatment groups lactic acid concentration (0.185-0.190%) were higher than the control group (0.164%). Antioxidant and Angiotensin converting enzyme inhibition activities of water soluble protein extracts were significantly (p<0.01) increased during ripening time. Antioxidant activity reached the highest level at 28^th d. There was no significant increase observed after fermentation for both activities. Antioxidant activity of encapsulated peptide added (%39.56-40.48) groups were higher than control (34.28%) and peptide added (33.99%) groups except MD1920 (38.30%). The effect of the ripening period of the sucuk samples on TBA values was found to be statistically significant (p<0.01) while treatment and 'ripening period × treatment' interaction were not to be significant (p<0.05). The value of hardness was the highest in the encapsulated peptide added groups (29.27, 35.83 N), and it was 20.40 N and 15.41 N in the peptide added group and the control group respectively.