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Objective: Edible seaweeds, valued for their rich content of bioactive compounds, have gained recognition in complementary medicine beyond their traditional role in the food and pharmaceutical sectors. Notable examples include Ulva rigida C.Agardh and Grateloupia turuturu Yamada. These seaweeds offer a promising avenue for exploring their bioactive potential in medical and dietary contexts. Methods: Hexane extracts were prepared to elucidate the fatty acid composition of seaweeds via Gas Chromatography-Mass Spectrometry analyses. Subsequently, investigations were conducted to assess the cytotoxicity on human breast cancer cell lines (MCF-7 and MDA-MB-231), as well as examine the antimicrobial and anti-cholinesterase activities of extracts obtained using hexane, dichloromethane:methanol (CH2Cl2:MeOH, 1:1), methanol (MeOH), and water solvents. Results: The most abundant substances for the U. rigida and G. turuturu species were hexadecanoic acid, octadecenoic acid, and erucic acid compounds. The CH2Cl2:MeOH (1:1) extract of G. turuturu was found as the highest toxicity on MCF-7 and MDA-MB-231 breast cancer cells (IC50: 28.7 µg/mL). G. turuturu extracts showed inhibition on E. coli and C. albicans. The hexane extracts of U. rigida and G. turuturu inhibited AChE enzyme in both algae species. Conclusion: The results highlight seaweeds’ bioactive potential for therapeutic and dietary products. Further research can explore medical and nutritional applications.

Yenilenebilir enerji kaynaklarından biri olan biyogaz enerjisi Türkiye’de yeni gelişmekte olan bir sektör haline gelmiştir. Türkiye’de mevcut biyogaz reaktörleri genellikle sürekli tip reaktörler olup substrat olarak sığır gübresi (SG) kullanmaktadır. Yapılan araştırmalara göre SG’nin biyogaz verimi literatürdeki verimlerinden oldukça düşük değerde (50-100 ml/g uçucu katı (UKSG)) çıkmaktadır. Bu nedenle SG’nin verimini artırmaya yönelik olan bu çalışma yapılmıştır. Bu bağlamda SG’nin biyogaz verimi laboratuvar ölçekli 5L’lik bir reaktörde endüstriyel reaktörlerin en çok kullandığı çalışma sıcaklığında (35 °C) test edilmiştir. Bu reaktör kontrol reaktörü olarak belirlendikten sonra çözünür karbonhidrat, protein ve yağlardan arınmış ve çoğunlukla lignoselülozik içeren reaktör kalıntısına %4 m/m NaOH ön işlemi ve sonrasında katalitik metallerden olan nikel (Ni) ve kobalt (Co) farklı konsantrasyonlarda (50, 100 ve 150 µg/toplam katı SG) eklenmiştir. Bu sayede kontrol reaktörüne kıyasla, bu metallerin belirli konsantrasyonun eklenmesi ile hidrojenotrofik aktiviteyi uyarabilen ve biyogaz üretimini daha da artırabilen bir sonuçla (%36 - 47) karşılaşılmıştır. En iyi Ni ve Co konsantrasyonu için SG’nin en yüksek biyogaz verimi toplam 509,5 ± 19,9 ml/g UK olmuştur.

Son zamanlarda nanopartiküllerin (NP)’lerin anaerobik sindirim (AS)’de biyogaz üretimi üzerinde verim artırmaya yönelik etkilerinin olduğu keşfedilmiştir. Bu çalışmada Fe3O4, ZnO ve SiO2 NP’lerin AS’ye olan etkileri incelenmiştir. Bazı NP’lerin yüksek konsantrasyonları toksik etki yapmaktadır. Bu nedenle substrat olarak kullanılan sığır gübresinin AS’de en iyi NP konsantrasyonlarını bulmak için Cevap yüzey yöntemi (CYY)’nin Box-Benkhen Tasarımı kullanılmıştır. CYY seçilen bir aralıktaki birkaç deney setine dayalı olarak işletim değişkenlerinden etkilenen yanıt yüzeyini en üst düzeye çıkaran değerli bir istatistiksel araçtır. Sonuç olarak bağımsız değişkenler için en iyi NP konsantrasyon değerleri SiO2 için 150 mg/l, Fe3O4 için 150 mg/l ve ZnO için 150 mg/l değerinde bulunmuştur. NP eklenmeden önceki biyogaz verimi 290 ml/g uçucu katı (UK) değerinde iken bağımsız değişkenlerin optimum koşullarında 320 ml/g UK değerinde tahmin edilmiştir. Varyans analizi ve yüksek regresyon katsayısı (%98), regresyon modeliyle deneysel değerlerin model tarafından iyi bir şekilde tahmin edildiğini doğrulamaktadır. Böylece gelecek çalışmalarda farklı NP’lerin AS’de etkilerinin birlikte incelenmesi önerilmektedir.

Today, energy demand has become one of the important problems. The rapid growth of the world population and the development of the industry have increased the need for energy. The vast majority of the world's energy needs come from natural energy sources. But the limited availability of these energy sources has led people to search for renewable energy sources. One of these renewable energy sources is biogas energy. Biogas is a gas mixture of organic substances formed by anaerobic microorganisms under anaerobic conditions at certain temperature conditions. It is flammable due to the presence of methane (CH4) gas in average 65% by volume in the biogas. Other gases outside the methane in the biogas are undesirable gases. Biogas purified from unwanted gasses is the natural gas used today. Biogas production gains importance in terms of disposal of organic materials. Black Sea Region in our country, due to the disadvantage of the geographical location and the lack of settlements has been very difficult to store the landfill. Biogas production in the Black Sea Region is gaining importance in terms of eliminating these wastes and obtaining energy. In this study, biogas potential of kitchen wastes of provinces in Black Sea Region was determined. The highest biogas potential of the Black Sea Region was found to be 51 163.20 m3 / day in Samsun province. The biogas potential of the kitchen wastes in the Black Sea Region was 296 015.18 m3/day.

Coronaviruses (CoVs) are causative agents of the last three epidemics/pandemic; severe acute respiratory syndrome CoV (SARS-CoV), Middle East respiratory syndrome-CoV (MERS-CoV) and the last one SARS-CoV-2. Although meta-analysis of treatment studies against these three CoVs found no clear benefit of any spesific regimen, currently, remdesivir and favipiravir are promising potential therapies for SARS-CoV-2. On the other hand, since natural products have always played a crucial role in drug discovery and development process against various diseases, many groups in the world, are now trying to find new or repurposed natural or naturally originated drugs against viruses and CoVs. Secondary metabolites of the plants, particularly alkaloids and terpenoids have been exhibited strong antimicrobial and anticancer activities besides synthetic drugs and other natural compounds (nucleosides and nucleotides and bacterial and fungi originated ones). The first isolated secondary metabolites have been converted into important drugs since 1800’s such as morphine, codeine, cocaine, and quinine have alkaloid skeleton as well as some of the recent anticancer drugs vinblastine, vincristine, taxol, etc. This review includes the last two decades of publications about natural alkaloids rather than their plant extracts which showed some promising results against CoVs. Marine organisms are also another rich source to discover new lead drugs, however they were excluded in the present review article.

In recent years, the world's natural energy resources unable to meet the increasing energy needs. In Turkey and in the world, there is an increasing need for renewable energy. One of the renewable energy sources is biogas energy. In this study, the biogas potential of Giresun, which is also known as coastal city, can be formed from 2 different organic wastes are experimentally calculated. Organic wastes included in the calculation; hazelnut shells (HS) and hazelnut wastes (HW). Production experiments were investigated in two ways: untreated and thermal pretreatment. In addition, biogas yield was examined at room temperature (23 °C), at mesophilic temperature (39 °C), and at thermophilic temperature (60 °C). As a result, the highest biogas yield was found at temperatures of 60 °C and under thermal pretreatment conditions. Under these conditions, annual biogas production potential of Giresun city was found as 38.21 GW h/yr. Keywords: Biogas, Thermal pretreatment, Hazelnut shells, Hazelnut wastes, Biogas potential