# Cold-Adapted Fungi: Goldmine of Biomolecules Applicable in Industry
## 4 Biotechnological Application of Psychrophilic Fungi in Food and Agriculture
### Other Bioactive Compounds  
The diverse, intricate, and advanced survival strategies of cold-adapted microorganisms may prove valuable for biotechnological applications. Cold-adapted microorganisms are a rich source of secondary metabolites with antibacterial and antifungal activity, isolated from various cold ecological niches on Earth [158; 159; 160]. The discovery of new and effective antimicrobial compounds is now a central focus of natural product chemistry. Cold environments have become a rich source of new antimicrobial compounds with unique structures and specific biological activities. Such substances may be employed in the medical field [158] and food technology as food protection agents [161]. In a study by [PERSON] et al. (2021), crude fungal extracts were tested for their antibiotic, antifungal, antiviral, and antiparasitic activities [14]. Among them, extracts of two Penicillin species associated with the endemic macroalgae _Palmaria decipients_ and _Monostroma hariotii_ contained compounds with high and selective antifungal and trypanicidal activities [68]. High antifungal activity against _Candida albicans_, _Candida krusei_, and _Cladosporium spharospernum_ was exhibited by extracts of _Pseudogymnoascus_, _Guehomyces pullulans_, and _Metschnikowia australis_. Interestingly, extracts from _Pseudogymnoascus_ sp. 5A-1C31 SIII, obtained from marine sediments in Admiralty Bay (South Shetland Islands, Antarctica), have been found to inhibit various phytopathogenic _Xanthomonas_ species. Another investigation on marine sediments from Deception Island (South Shetland Islands, Antarctica) resulted in the isolation of _Pseudogymnoascus_ and _Simplicillium lamellicola_, which demonstrated high and selective antifungal activity against _Paracoccidioides brasiliensis_[14]. A growing number of studies on bioactive compounds focus on their use in agricultural applications as plant protection or plant growth-promoting agents. However, in response to the increasing preference for reducing chemical usage, cold-adapted yeast has emerged as a potential alternative strategy for biological control [161]. Currently, fungicides are primarily employed to protect fruits and vegetables from fungal infestation during and after harvesting. However, the quantities of chemicals used are being reduced annually due to the growing trend towards environmentally and human-friendly substances. Furthermore, most pathogens are becoming resistant to the substances currently in use [161]. In recent years, there has been growing interest in exploring the potential of yeast as a biological control agent to protect crops from post-harvest disease [162]. The use of these antagonistic microorganisms presents many significant advantages. These include their natural presence on fruit surfaces, resistance to stress factors, non-production of harmful substances, and ease of cultivation. There is no doubt that yeasts offer an  
Figure 5: Potential application of low-temperature biosurfactants in food industry and agriculture. unbeatable combination of advantages, making them the perfect alternative to existing substances [163; 164]. Psychrotolerant and psychrophilic yeasts provide an ideal solution that could significantly improve the protection of fruits and vegetables stored or transported at low temperatures. Research conducted by [PERSON] et al. (2013) demonstrated that _Leucosporidium scotti_ At17 produces volatile compounds that inhibit the growth of pathogens on apples [165]. Similarly, the psychrophilic strain _Candida sake_ has been shown to possess analogous properties [166]. Meanwhile, the yeast species _Cryptococcus albidus_ and _Pichia membranifaciens_ have been observed to act as biological agents on pears at 5 \({}^{\circ}\)C for up to 100 days [167]. Additionally, yeast has been demonstrated to inhibit the growth of blue and green molds on oranges [168], as well as grey molds on strawberries [164]. The potential of yeast as an effective biological agent is still largely untapped.