Biyoaktif bileşik üretim potansiyeli yüksek olan aktinobakteriler antibiyotik, antitümör ajanı, bitki gelişimini teşvik eden faktörler ve enzimler üretebilmektedirler. Yeni biyoaktif bileşiklerin keşfi için faklı ekstrem ortamlardan izolasyon çalışmaları yapılmaktadır. Bu çalışmada, Sakarya Nehir kaynağının sedimentinden ilk kez aktinobakteri izolasyonu ve bu bakterilerin ürettiği farklı bioaktif metabolitlerin varlığı araştırlmıştır. Antimikrobiyal aktivite deneylerinde Gram pozitif, Gram negatif bakteriler, maya ve funguslar kullanılmıştır. İzolatların azotu (N) fikse edebilme inorganik fosfatı çözebilme yeteneklerine, indol asetik asit (IAA) üretebilme ve kazeinaz aktivitelerine bakılmıştır. 17 aktinobakteri izolatının 16S rDNA analizleri sonucunda, izolatlar Micromonospora sp., ( 14), Saccharomonospora sp. (2) ve Cellulomonas sp. (1) olarak tanımlanmıştır. Elde edilen sonuçlarda, Micromonospora izolatlarının Gram pozitif bakterilere, maya ve funguslara karşı etkin olduğu belirlenmiştir. 12 izolatın N'u fikse edebildiği, 7 izolatın IAA üretebildiği, 2 izolatın kazeinaz aktivitesine sahip olduğu görülmüştür. Antimikrobiyal özellikleri açısından yüksek aktiviteye sahip olanların iyi birer farmasötik aday olabileceği ve bitki gelişimini teşvik edici potansiyele sahip izolatların da tarım alanında biyogübre olarak kullanım potansiyeline sahip olduğu düşünülmektedir. Ayrıca, 16S rDNA dizi analizleri sonucunda 2 Micromonospora, Saccharomonospora sp. ve Cellulomonas sp. Suşlarının yeni birer tür olması söz konusudur.

Haloalkalitolerant fungi can grow at environments had high salt concentrations and pH values. The bioactive compounds produced under stressful conditions have potential biotechnological applications. In this study, 52 microfungi isolated from Acıgöl Lake/Turkey, offering polyextreme conditions, were screened for some biotechnological properties. The antimicrobial and antioxidant activities were determined using the agar diffusion and the DPPH radical scavenging method, respectively. Starch-iodine method, tributyrin plate assay, skim milk plate assay, carboxymethyl cellulose plate method were used for determining amylolytic, lipolytic, proteolytic and cellulolytic activity, respectively. Synthesis of silver nanoparticle was carried out using cell-free filtrate of microfungi. As a result, 40% of the isolates showed antimicrobial activity against at least one of the test microorganisms. Penicillium dipodomyicola showed the highest antibacterial activity against Gram positive and negative test bacteria, while P. brevicompactum showed the highest activity against Candida albicans. P. dipodomyicola and P. bilaiae were found to have free radical scavenging activity of a level (90% and above) that can compete with positive control. All of the isolates with amylase activity belonged to Aspergillus and Penicillium genera and the most prominent three of them were A. ochraceous, P. brevicompactum and A. flavus. While 55% of the isolates showed proteolytic activity, A. alliaceus had the highest activity. Almost all the isolates (92%) showed lipolytic activity. It was determined that especially the isolates of A. amstelodami, P. sizovae and P. solitum had a significant level of lipolytic activity. 35% of the isolates showed cellulolytic activity and in isolates of Cladosporium pseudocladosporioides, P. dipodomyicola and P. bilaiae were observed high activity. Eight of the isolates carried out AgNP synthesis within 24 h. When all the results were evaluated, it was determined that the isolates such as Aspergillus amstelodami, A. ochraceus, Penicillium dipodomyicola, and P. brevicompactum, have the potential to serve in different industrial areas.

In recent years, plant growth promoting bacteria (PGPB) have been used as biofertilizers that increase agricultural productivity and plant resistance to changing environmental conditions such as drought, salinity and heat stress. One of the proposed new approaches to increase plant productivity, especially under stress conditions, is using algae extracts, naturally occurring bioactive compounds. Paenibacillus sp. S1S22 isolated from sediment was tested for its performance in indole acetic acid production (IAA), nitrogen (N) fixation, phosphate solubilization, proteolytic activity, and cellulose activity. It was also determined antimicrobial activity against different pathogens of this strain. Tomato seeds were incubated with the S1S22 strain, and the S1S22 strain supplemented U. lactuca. It was used as a control group that seeds were incubated with deionized water. We obtained results and demonstrated the addition of Ulva lactuca extract to tomato seedlings incubated with Paenibacillus sp. S1S22 strain increased the root and stem length compared to the control. The results indicate that macroalgae in combination with PGPR may be a much more effective way of promoting plant growth.