Current Bioactive Compounds - Volume 17, Issue 4, 2021

Background: Algae, tiny photosynthetic microorganisms are under investigation for commercial biofuels and biochemical production. Applications of bioactive compounds of algal origin are now increasing for food, feed, fodder, fibre, cosmetics, nutraceutical and pharmaceuticals. Recent years have witnessed a major thrust moving towards a sustainable, biobased economy using a biorefinery concept. The biorefinery concept is based on obtaining a broad spectrum of products such as biodiesel, bioethanol, biogas, jet fuels, and many value-added biobased products from renewable bioresources analogous to the petroleum refinery. Methodology: The aim of this review is to provide an insight into the utilization of algal biomass for the production of bioactive compounds, algal cultivation systems, cell disruption techniques, challenges to algal bioactive compound extraction, and offer a way forward. According to this objective, we did a comprehensive search in all available electronic information resources like in Web of Science, Scopus, and Science Direct. Results: The review summarizes representative bioactive compounds from algal biomass, indicating that these biological resources are an inexhaustible source of new molecules that often display unique structures and sometimes have very interesting pharmacological properties, such as antifungal, antibacterial, enzyme-inhibitory, and other activities. A better cultivation and cell disruption strategy have been suggested for a sustainable algal biorefinery system. Conclusion: The paper reviewed different bioactive compounds like astaxanthin, DHA, EPA, vitamins and β-1,3 Glucan, etc. present in microalgae and their applications in pharmaceuticals and nutraceuticals development for human consumption along with major steps of algal bioprocessing, such as algal cultivation and cell disruption. Also, the production and role of several high-value compounds extracted from algal biomass in the treatment of various diseases along with the way forward to make algal-based biorefinery for bioactive compounds economically sustainable and viable have been discussed. However, research on various aspects of algal based bioactive compound extraction is in a nascent phase and requires bioprospecting of high yielding native algal species, development and deployment of mass cultivation strategies, process optimization for harvest and cell disruption techniques followed by efficient biomolecule extraction procedures to make algal biorefinery sustainable and commercially viable in nature.

Background: Curcumin, principal constituent extracted from dried rhizomes of Curcuma longa L., is a hydrophobic polyphenol meant to cure chronic malignancies like rheumatoid arthritis, Alzheimer’s, Inflammatory bowel disease and many common ailments related to colon, lung, stomach and skin. The objective of this review is to study the synergistic effect of curcumin. Methods: Current prose emphasizes the synergistic effect of curcumin as a part of cancer treatment and other ailments have been identified and reviewed with particular emphasis on their scientific impact and novelty. Results: A number of synergistic combinations have emerged with the growth of biological data sets that can prove to be useful for the pharmaceutical industry. Conclusion: This present review will be help the researchers and industries in drug development as a new paradigm of drug discovery.

Background: Many bioactive molecules, such as lycopene, resveratrol, lignan, tannins, indoles, fatty acids, etc., found in small amounts in plants, animals, and micro-organisms have been extensively investigated for their diverse preventive, therapeutic, immune-modulating and toxicological effects. Currently, the growing interest of the consumers is shifted towards a novel bioinspired strategy of cocktailing two or more bioactives at a lower concentration to reduce both side and cost effects, and to enhance positive effects for the development of novel compounds by the food, pharmaceutical, and chemical industries. Methods: Even though there are several regularly updated and published reports showing the importance of beneficial effects of bioactives individually, no systematic reviews are outlining how the bioactives have combinatorially acted together to provide such health benefits and disease preventive effects. Hence, various electronic scientific databases, such as Pub Med, Science Direct, Google scholar, Sci-Finder were searched to collect the data of the present review. Results: One hundred and sixty-two research and review papers collected from peer-reviewed journals are cited in the present review covering the broad spectrum of many bioactives and their importance in the field of food, feed, and drug industries. Conclusion: The present systematic review discusses and highlights the current knowledge on the concept of synergistic and combinatorial effects of various bioactives from the plant, animal, micro- organism sources, and synthetic drugs in disease prevention and health promotion. These findings may pave a way for the discovery of new bioactive products and process development, which could add to economic importance.

Background: Tuberculosis (TB) continues to be the most threatening cause of death in recent years. There is an urgent need to search more potent, less toxic antitubercular agents. Methods: A set of five new 1,3,4-oxadiazolyl-imidazo-1,2-pyridine derivatives (4a-4e) was synthesized and screened in-vitro for their antibacterial activity against Mycobacterium tuberculosis (H37 RV strain) ATCC No-27294. Results: Compound 4b displayed potent antitubercular activity at MIC 6.25 μg/mL. In-silico molecular docking studies were performed for the evaluation of the binding patterns of compounds 4a-4e in the binding site of proteins like, Pantothenate synthatase and enoyl acyl reductase inhibitor. The outcomes of the in-vitro antitubercular studies were in good agreement with the molecular docking studies. These newly synthesized compounds were found to have a good ADMET profile. We also explored possible anticancer activity using in-silico methods. Conclusion: These results show that readily synthesized 1,3,4-oxadiazolyl-imidazo-1,2-pyridine derivatives (4a-4e) are attracting a new class of potent anti-TB targets as well as possible anticancer activity that worth additional opportunities for improvements.

Background: A series of new zerumbone hydrazones 5a-f and 9a-f have been synthesized in via an in situ procedure in high yields. The structure of synthesized compounds has been confirmed using ¹H, ¹³C NMR and HR-MS. The bioassay result showed that several compounds exhibited cytotoxic effects against three human cancer cell lines, including HepG-2, SK-LU-1, and MCF-7. Compound 9a showed the best cytotoxic effect against HepG-2, SK-LU-1, and MCF-7 with IC50 values of 8.20, 6.66, and 9.35 μM, respectively. Objective: This study aims at developing new zerumbone hydrazones as anticancer agents based on zerumbone, a natural compound wildly growing in Vietnam.

Methods: A series of new zerumbone hydrazones was designed, synthesized, and evaluated for cytotoxicity against three human cancer cell lines, including HepG-2, MCF-7, and SKLu-1, using the MTT method. Results: The bioassay result showed that several compounds exhibited cytotoxic effects against three human cancer cell lines, including HepG-2, SK-LU-1, and MCF-7. Especially, compound 9a displayed the best cytotoxic effect against HepG-2, SK-LU-1, and MCF-7 with IC50 values of 8.20, 6.66, and 9.35 μM, respectively. Conclusion: The research results suggest that some compounds could be considered as leads for the future design of zerumbone hydrazones in which bio-isosteric replacements in theortho position of the phenyl ring could be performed to improve the cytotoxic activity.

Background: In recent years, multidrug resistance to antimicrobial agents, including antibiotics, has constantly been evolving, despite the diversity of these agents. However, such factors as the undesirable side-effects they cause, and sometimes the relatively expensive treatment costs, adaptation and new resistance mechanisms of microorganisms that emerged and spread globally, led many people to use bioactive compounds for treatment in the form of plant extracts known for their antimicrobial properties. The world health organization statistics estimate that medicinal plants, as basic drugs, are used by two-thirds of the world's population. Recent studies have focused on finding plants around the world with the appropriate and effective extract to be used as antimicrobial drugs. Fenugreek (Trigonella foenum-graecum L.) is an annual herb that is widely consumed globally as food, feed additive, and in herbal medicines as traditional remedies. Taking this into account, the present work aimed to study the phytoconstituents and in vitro antimicrobial activity of fenugreek seeds cultivated in Taghit region (Southwest of Algeria) against some uropathogenic bacterial strains. Methods: Qualitative tri phytochemical screening was carried out according to a standard protocol, based on staining and/or precipitation reactions, while the antibacterial test of two aqueous extracts and flavonoid, as selective extracts (n-butanolic and ethyl acetate fractions), was carried out by agar well diffusion method against a selection of Gram-positive and Gram-negative uropathogenic bacteria. Results: The obtained results showed a composition rich in phytoconstituents, especially in polyphenol, from where does probably comes the antibacterial effect that was ranging switched from low to strong effect on the majority of the tested strains with a stronger action attributed to flavonoid extracts compared to moderate effect of aqueous extracts. These results are linked not only to the extracts’ nature but also to the antibiotic resistance that was observed in the testing results for the isolated and reference bacterial strains where the isolated uropathogenic strains were multidrug- resistant against more than three classes of antibiotics, mainly: aminopenicillins, cephalosporins, 1st generation quinolones and also many others, such as Escherichia coli, Klebsiella spp, and P. aeruginosa species while most Staphylococcus sp strains were resistant to penicillin, tetracycline, and cotrimoxazole. Conclusion: However, flavonoids showed a greater effect compared to the antimicrobial activity of gentamicin, where Gram-positive uropathogenic isolates were more susceptible, with an activity index (AI) of 1 to 2.5 for S. aureus strains at concentrations of 27 to 223mg/mL. However, Gramnegative reference bacterial strains showed an activity index of 1 to 1.21 for E. coli, Citrobacter freundii, and Pseudomonas aeruginosa strains.

Aims and Objective: Various studies revealed the antioxidant and anti-inflammatory properties of Psidium guajava leaves. This present study reported the anti-inflammatory and protective effects of Psidium guajava leaves on Carbon tetrachloride (CCl4) induced rat liver. Methods: In this study, Long Evans female rats (150-180 g) were divided into four groups. CCl4 in olive oil was given orally by gavage at a dose of 1 mL/kg and Psidium guajava leave powder was provided as 2.5% w/w of food. Liver marker enzyme activity was monitored by evaluating the alanine Aminotransferase (ALT), Aspartate Aminotransferase (AST) and Alkaline Phosphatases (ALP) in plasma. The plasma and liver tissue concentrations of thiobarbituric acid reactive substances (TBARS), Nitric Oxide (NO), advanced protein oxidation product (APOP), glutathione (GSH, in reduced form) and activity of catalase were measured as an oxidative stress marker. Results: The results of this study suggested the serum transferase activities were increased in CCl4 administered rat, which was normalized by Psidium guajava leaves supplementation. Moreover, oxidative stress markers were significantly reduced and antioxidant enzyme activity was significantly improved by Psidium guajava leaves supplementation in CCl4 administered rat. Hematoxylin and Eosin and Picrosirius Red staining of liver section revealed reduced inflammatory cell infiltration and fibrosis, respectively by Psidium guajava leaves supplementation in CCl4 administered rats. Conclusion: In conclusion, Psidium guajava leaves may prevent liver damage and inflammation in CCl4-administered rats, which indicated strong antioxidant capacity. Thus, Psidium guajava leaves could be a source of natural antioxidants. Further study is required for using Psidium guajava leaves in the clinical case of liver dysfunction.