Antihyperglycemic and anti-inflammatory effects of fermented food paste on high-fat diet and streptozotocin-challenged mice

Background: Fermented food has been widely consumed as health food to ameliorate or prevent several chronic diseases including diabetes. Xeniji™, a fermented food paste (FFP), has been previously reported with various bioactivities, which may be caused by the presence of several metabolites including polyphenolic acids, flavonoids, and vitamins. In this study, the anti-hyperglycemic and anti-inflammatory effects of FFP were assessed. Methods: In this study, type 2 diabetes model mice were induced by streptozotocin and high-fat diet (HFD) and used to evaluate the antihyperglycemic and anti-inflammatory effects of FFP. Mice were fed with HFD and challenged with 30 mg/kg body weight (BW) of streptozotocin for 1 month followed by 6 weeks of supplementation with 0.1 and 1.0 g/kg BW of FFP. Metformin was used as positive control treatment. Results: Xeniji™-supplemented hyperglycemic mice were recorded with lower glucose level after 6 weeks of duration. This effect was contributed by the improvement of insulin sensitivity in the hyperglycemic mice indicated by the oral glucose tolerance test, insulin tolerance test, and end point insulin level. In addition, gene expression study has shown that the antihyperglycemic effect of FFP is related to the improvement of lipid and glucose metabolism in the mice. Furthermore, both 0.1 and 1 g/kg BW of FFP was able to reduce hyperglycemia-related inflammation indicated by the reduction of proinflammatory cytokines, NF-kB and iNOS gene expression and nitric oxide level. Conclusion: FFP potentially demonstrated in vivo antihyperglycemic and anti-inflammatory effects on HFD and streptozotocin-induced diabetic mice

Chemical Constituents and Biological Activities of Curcuma Xanthorrhiza and Curcuma Heyneana

Five compounds were isolated from Curcuma xanthorrhiza. The hexane extract afforded three pure compounds, which were identified as α- curcumene (21), germacrone (17) and zederone (66), while dichloromethane extract gave yellow powder product, which was characterized as curcumin (5) together with colourless oil, xanthorrhizol (16). The studies on Curcuma heyneana afforded four compounds. The hexane extract yielded oxycurcumenol epoxide (64), which is a new natural product, isocurcumenol (31) and curcumenol (32). In addition, dichloromethane extract produced stigmasterol (65). The following biological activities; larvicidal, cytotoxicity and antimicrobial activities carried out on these plants have not been reported previously. However the antioxidant activity has been reported. The results of bioactivity tests revealed that some of the plant crude extracts showed strong biological activities. Nevertheless, most of the isolated pure compounds showed only weak to moderate activity. Larvicidal test results both on the plants crude extracts showed that non polar extracts exhibited high toxicity with a LC50 value between 26.4 μg/ml and 34.9 μg/ml. On the other hand, curcumin (5) and curcumenol (32) showed antimicrobial activity against Staphylococcus aureus and Pseudomonas aeruginosa. The results obtained for antioxidant activity test revealed that curcumin (5) possessed stronger antioxidant activity, while the isolated pure compounds from C. heyneana were not active in the assay. Cytotoxicity activity on the isolated pure compounds from C. heyneana including oxycurcumenol epoxide (64), curcumenol (32) and isocurcumenol (31) exhibited moderate cytotoxic activity with IC50 values 11.9, 12.6 and 13.3 μg/ml, respectively, while curcumin (5) showed strongest inhibitory activity with IC50 value 9.1 μg/ml

Assessment of Cosmeceutical Potentials of Selected Mushroom Fruitbody Extracts Through Evaluation of Antioxidant, Anti-Hyaluronidase and Anti-Tyrosinase Activity

Cosmeceutical formulations containing naturally derived active ingredients are currently preferred by consumers worldwide. Mushrooms are one of the potential sources for cosmeceutical ingredients but relevant research is still lacking. In this study, hot- and cold-water extractions were performed on four locally-cultivated mushrooms—Pleurotus ostreatus, Ganoderma lucidum, Auricularia polytricha and Schizophyllum commune—with the aim to assess the cosmeceutical potential of these mushroom fruitbody extracts. Total phenolics, polysaccharide and glucan content were determined. Antioxidant property of the mushroom extracts was assessed by determining the DPPH radical scavenging, ferric-reducing (FRAP) and superoxide anion (SOA) scavenging activity. Anti-hyaluronidase activity was used as an indicator for the anti-aging and anti-inflammatory property, while anti-tyrosinase activity was evaluated to assess the anti-pigmentation or whitening property of these extracts. Our results showed that total polysaccharide content of P. ostreatus extracts was the highest (235.8–253.6 mg GE/g extract), while extracts from G. lucidum contained the lowest glucan (10.12–10.67%). Cold-water extract from S. commune exhibited substantial tyrosinase inhibition activity (98.15%) and SOA scavenging activity (94.82%). The greatest hyaluronidase activity was exhibited by G. lucidum hot-water extract, with the value of 72.78%. The findings from the correlation analyses suggest that the cosmeceutical properties of these mushrooms can be attributed mainly to the combination of different types of compound such as polysaccharides and phenolics. Overall, cold-water extract of S. commune and hot-water extract of G. lucidum showed the best results and may be further investigated

Cosmeceutical potentials and bioactive compounds of rice bran fermented with single and mix culture of Aspergillus oryzae and Rhizopus oryzae

In the present study, rice bran, one of the most abundant agricultural by-products in Malaysia, was fermented with single and mixed cultures of Aspergillus oryzae and Rhizopus oryzae. The fermented rice bran extracts were tested for their functional properties and compared to the non-fermented counterparts. Antioxidant activities as well as phenolics and organic acid contents were evaluated. Skincare-related functionalities were also tested by evaluating tyrosinase and elastase inhibition activities. Tyrosinase inhibition activity, measured to determine the anti-pigmentation effect of extracts, was found to be the highest in the extract of rice bran fermented with A. oryzae (56.18%) compared to other extracts. In determining the anti-aging effect of fermented rice bran extracts, the same extract showed the highest elastase inhibition activity with a value of 60.52%. Antioxidant activities were found to be highest in the mix-cultured rice bran extract. The results of phenolic and organic acid content were varied; the major phenolic acid detected was ferulic acid with a value of 43.19 μg/ml in the mix-cultured rice bran extract. On the other hand, citric acid was the major organic acid detected, with the highest content found in the same extract (214.6 mg/g). The results of this study suggest that the fermented rice bran extracts may have the potential to be further exploited as ingredients in cosmetics as well as in antioxidant-rich products

Evaluation of antioxidant and antibacterial activities of fish protein hydrolysate produced from Malaysian fish sausage (Keropok Lekor) by-products by indigenous Lactobacillus casei fermentation

Malaysian fish sausage, Keropok Lekor (KL), is a popular fish snack in Malaysia. The fish by-products (FBPs) from KL processing comprise a significant quantity of proteins with high nutritional value. However, in Malaysia, such FBPs are either disposed of into waterways, which may cause environmental pollution, or are processed into products of low economic value, such as fertiliser and animal feed. To maximise the potential of FBPs, a microbial fermentation approach can be used to convert FBPs into bioactive fish protein hydrolysate (FPH). Bioactive FPH has higher economic value due to its potential as a bio-ingredient in the nutraceutical and functional food industries. This study aimed to evaluate antioxidant and antibacterial activities of FPHs from FBPs of KL processing produced by four indigenous Lactobacillus casei strains (LC216, LC217, LC219, and LC220). The relationship between the level and composition of free amino acids during fermentation and the antioxidant and antibacterial activities of the produced FPH was evaluated. The results showed that the FPHs produced using the four L. casei strains had higher 2,2-Diphenyl-1-picrylhydrazyl (DPPH) radical scavenging activities (82.8–88.4%) than that of the unfermented FBPs (78.9%). The obtained half-maximal effective concentrations (EC50) of the FPHs were also significantly lower (p < 0.05) than those of the unfermented FBPs. The ferrous chelating ability of the FPHs produced using strain LC217 improved by 68.43% compared to that of the unfermented FBPs. Furthermore, compared to the unfermented FBPs, the FPHs produced using strains LC216 and LC217 had a significantly higher (p < 0.05) maximum growth inhibition against Listeria monocytogenes, Salmonella typhimurium, Escherichia coli and Listeria innocua. Moreover, there was a positive relationship between the degree of hydrolysis and the bioactivities. A strong positive correlation also existed between the level of antioxidant amino acids content and antioxidant activity. Overall, the L. casei fermentative production of bioactive FPHs from the FBPs from KL processing represents an effective, environmentally sustainable and economical strategy for producing bioactive bioingredients, which can be used in functional food production and food preservation

Screening of Potential Tannase-producing Fungi from Local Agri-industrial By-products using a Plate Assay and Submerged Fermentation

Tannase (Tannin Acyl Hydrolase EC 3.1.1.20) is an industrial inducible enzyme capable of hydrolyzing hydrolyzable tannin ester linkage gallotannin and ellagitannin, producing gallic acid and glucose. Tannase is extensively used in the pharmaceutical, chemical, cosmetics, textile, leather, food, feed, and beverage industries. In the beverage industry, tannase is used as a clarifying agent to clarify tannin present in coffee, coffee-flavored soft drinks, tea, and fruit juices by removing phenolic compounds. In the pharmaceutical industry, tannase is used to produce gallic acid, an intermediary compound in the production of antibacterial drug, trimethoprim, while in the food industry, tannase is used to synthesize crucial antioxidant food preservative propyl gallate (3,4,5-trihydroxybenzoate). Most of the tannase production utilizes bacteria such as Bacillus sp. as tannase producer under submerged fermentation, SmF. Despite the immense industrial potential of tannase, it has not fully been exploited due to lack of knowledge, and fewer studies reported filamentous fungi for tannase production. This study aimed to screen potential tannase-producing fungi from various agri-industrial by-products such as rice by-products, spent tea, spent coffee ground, banana peels, mango peels, desiccated coconut residue, soybean residue, sweet potato peels, and onions. Fungal isolate, J1 (Aspergillus niger) was identified as the efficient tannase-producing fungus due to the hydrolytic zone's largest diameter (60.7 ± 0.6) mm. It achieved high tannase activity with (6.86 ± 0.04) U/ml in submerged fermentation, SmF. In conclusion, filamentous fungi isolated from agri-industrial by-products have huge potential as an efficient tannase producer