No abstract

Rice is a staple food source for more than three billion people worldwide. However, rice is vulnerable to diseases, the most destructive among them being rice blast, which is caused by the fungus Magnaporthe oryzae (anamorph Pyricularia oryzae). This fungus attacks rice plants at all stages of development, causing annual losses of approximately 10–30% in various rice producing regions. Synthetic fungicides are often able to effectively control plant diseases, but some fungicides result in serious environmental and health problems. Therefore, there is growing interest in discovering and developing new, improved fungicides based on natural products as well as introducing alternative measures such as biocontrol agents to manage plant diseases. Streptomyces bacteria appear to be promising biocontrol agents against a wide range of phytopathogenic fungi, which is not surprising given their ability to produce various bioactive compounds. This review provides insight into the biocontrol potential of Streptomyces against the rice blast fungus, M. oryzae. The ability of various Streptomyces spp. to act as biocontrol agents of rice blast disease has been studied by researchers under both laboratory and greenhouse/growth chamber conditions. Laboratory studies have shown that Streptomyces exhibit inhibitory activity against M. oryzae. In greenhouse studies, infected rice seedlings treated with Streptomyces resulted in up to 88.3% disease reduction of rice blast. Studies clearly show that Streptomyces spp. have the potential to be used as highly effective biocontrol agents against rice blast disease; however, the efficacy of any biocontrol agent may be affected by several factors including environmental conditions and methods of application. In order to fully exploit their potential, further studies on the isolation, formulation and application methods of Streptomyces along with field experiments are required to establish them as effective biocontrol agents.

Colorectal cancer (CRC) is the third most prevalent form of cancer, after lung cancer and breast cancer, with the second highest death incidence. Over the years, natural compounds have been explored as an alternative to conventional cancer therapies such as surgery, radiotherapy, and chemotherapy. Curcumin, an active constituent of turmeric has been associated with various health benefits. It has gained much attention as an anticancer agent due to its ability to regulate multiple cell signaling pathways, including NF-κB, STAT3, activated protein-1 (AP-1), epidermal growth response-1 (Egr-1), and p53, which are crucial in cancer development and progression. Nevertheless, the clinical application of curcumin is greatly restricted because of its low water solubility, poor oral absorption, and rapid metabolism. These issues have led to the development of curcumin nanoformulations to overcome the limitations of the compound. Nanotechnology-based delivery systems have been widely used in improving the delivery of poorly-water soluble drugs. Besides, these systems also come with the added benefits of possible cellular targeting and improvement in cellular uptake. An ideal improved formulation should display a greater anticancer activity compared to free curcumin, and at the same time be non-toxic to the normal cells. In this review, we focus on the design and development of various nanoformulations to deliver curcumin for use in CRC such as liposomes, micelles, polymer nanoparticles, nanogels, cyclodextrin complexes, solid lipid nanoparticles (SLN), phytosomes, and gold nanoparticles. We also discuss the current pre-clinical and clinical evidences of curcumin nanoformulations in CRC therapy, analyse the research gap, and address the future direction of this research area.

Vibrio vulnificus is a Gram negative, rod shaped bacterium that belongs to the family Vibrionaceae. It is a deadly, opportunistic human pathogen which is responsible for the majority of seafood-associated deaths worldwide. V. vulnificus infection can be fatal as it may cause severe wound infections potentially requiring amputation or lead to sepsis in susceptible individuals. Treatment is increasingly challenging as V. vulnificus has begun to develop resistance against certain antibiotics due to their indiscriminate use. This article aims to provide insight into the antibiotic resistance of V. vulnificus in different parts of the world as well as an overall review of its clinical manifestations, treatment, and prevention. Understanding the organism's antibiotic resistance profile is vital in order to select appropriate treatment and initiate appropriate prevention measures to treat and control V. vulnificus infections, which should eventually help lower the mortality rate associated with this pathogen worldwide.

Surfactin, a cyclic lipopeptide biosurfactant produced by various strains of Bacillus genus, has been shown to induce cytotoxicity against many cancer types, such as Ehrlich ascites, breast and colon cancers, leukemia and hepatoma. Surfactin treatment can inhibit cancer progression by growth inhibition, cell cycle arrest, apoptosis, and metastasis arrest. Owing to the potent effect of surfactin on cancer cells, numerous studies have recently investigated the mechanisms that underlie its anticancer activity. The amphiphilic nature of surfactin allows its easy incorporation nano-formulations, such as polymeric nanoparticles, micelles, microemulsions, liposomes, to name a few. The use of nano-formulations offers the advantage of optimizing surfactin delivery for an improved anticancer therapy. This review focuses on the current knowledge of surfactin properties and biosynthesis; anticancer activity against different cancer models and the underlying mechanisms involved; as well as the potential application of nano-formulations for optimal surfactin delivery.