Evaluation of the Biological Activities of Two Macro-Algae Collected from the Red Sea of Jeddah

Marine algae were used in many biological applications. Two marine algal samples, Halimeda tuna and Dictyota dichotoma, were collected from Obhur region, Jeddah, Saudi Arabia, washed with water, dried and extracted with methanol. The antimicrobial activities were conducted against some pathogenic bacteria. The results showed that the extracts of both Halimeda tuna and Dictyota dichotoma were active against at least one of the tested organisms. The highest antimicrobial activities of the extracts Halimeda tuna and Dictyota dichotoma were against Staphylococcus aureus and Streptococcus pneumonia. On contrast, both Halimeda tuna and Dictyota dichotoma showed weak inhibition against Pseudomonas aeruginosa and Acinetobacter baumannii. Moreover, the mixture of the two algal extracts showed excellent inhibition for all the tested bacteria. In addition, a toxicological experiment was conducted for the two algal extracts using Artemia salina as test organism. No toxicity was found for the two tested methanolic extracts.   Furthermore, moderate antitumor activity was recorded for the two tested algal extracts against two cell lines, MCF-7 (breast cancer) and HepG2 (hepatocellular carcinoma) using in vitro MTT and Neutral Red assays. Also, the chemical analysis of each algal extract was carried out. In conclusion, these algal extracts inhibited some pathogenic microbes and can be used as antimicrobial agents.  In conclusion, the two collected macro- algae showed antibacterial activities specially against Salmonella which contaminate food, thus the powder or the extracts of these two algae can be used safely as food additive

Biodegradation of Some Polycyclic Aromatic Hydrocarbons by a Bacterial Consortium Isolated from the Red Sea of Jeddah

Polycyclic aromatic hydrocarbons (PAHs) are considered organic pollutants, which are stable, highly toxic, and carcinogenic. Therefore, it was necessary to find an environmentally friendly way to degrade these compounds and remove them from polluted environments. Water samples polluted with petroleum hydrocarbons were collected from the coast of Jeddah on the Red Sea - Saudi Arabia. The results of the current study showed the ability of bacterial consortium that was enriched from the coast of Jeddah, Saudi Arabia to degrade petroleum hydrocarbons wastewater, which proved its ability to degrade PAHs in saline conditions. The bacterial union degraded BENZ compound by more than 95% at the concentration of 100 and 250 mg/L, while the degradation of this compound at the concentration of 1000 mg/L was recorded about 83% while the ANT degradation rate was recorded at more than 90% at different concentrations. In addition, this study revealed the ability of bacterial consortium to treat petroleum hydrocarbons wastewater in bioreactor (CSTR) with 92.7% of COD removed under saline conditions. Hence, this study recommends the investment of bacterial consortium in the treatment of petroleum hydrocarbons wastewater in marine environments and to remove pollutants from them

Evaluation of the Biological Activities of Two Macro-Algae Collected from the Red Sea of Jeddah

Marine algae were used in many biological applications. Two marine algal samples, Halimeda tuna and Dictyota dichotoma, were collected from Obhur region, Jeddah, Saudi Arabia, washed with water, dried and extracted with methanol. The antimicrobial activities were conducted against some pathogenic bacteria. The results showed that the extracts of both Halimeda tuna and Dictyota dichotoma were active against at least one of the tested organisms. The highest antimicrobial activities of the extracts Halimeda tuna and Dictyota dichotoma were against Staphylococcus aureus and Streptococcus pneumonia. On contrast, both Halimeda tuna and Dictyota dichotoma showed weak inhibition against Pseudomonas aeruginosa and Acinetobacter baumannii. Moreover, the mixture of the two algal extracts showed excellent inhibition for all the tested bacteria. In addition, a toxicological experiment was conducted for the two algal extracts using Artemia salina as test organism. No toxicity was found for the two tested methanolic extracts.   Furthermore, moderate antitumor activity was recorded for the two tested algal extracts against two cell lines, MCF-7 (breast cancer) and HepG2 (hepatocellular carcinoma) using in vitro MTT and Neutral Red assays. Also, the chemical analysis of each algal extract was carried out. In conclusion, these algal extracts inhibited some pathogenic microbes and can be used as antimicrobial agents.  In conclusion, the two collected macro- algae showed antibacterial activities specially against Salmonella which contaminate food, thus the powder or the extracts of these two algae can be used safely as food additive

Biodegradation of Some Polycyclic Aromatic Hydrocarbons by a Bacterial Consortium Isolated from the Red Sea of Jeddah

Polycyclic aromatic hydrocarbons (PAHs) are considered organic pollutants, which are stable, highly toxic, and carcinogenic. Therefore, it was necessary to find an environmentally friendly way to degrade these compounds and remove them from polluted environments. Water samples polluted with petroleum hydrocarbons were collected from the coast of Jeddah on the Red Sea - Saudi Arabia. The results of the current study showed the ability of bacterial consortium that was enriched from the coast of Jeddah, Saudi Arabia to degrade petroleum hydrocarbons wastewater, which proved its ability to degrade PAHs in saline conditions. The bacterial union degraded BENZ compound by more than 95% at the concentration of 100 and 250 mg/L, while the degradation of this compound at the concentration of 1000 mg/L was recorded about 83% while the ANT degradation rate was recorded at more than 90% at different concentrations. In addition, this study revealed the ability of bacterial consortium to treat petroleum hydrocarbons wastewater in bioreactor (CSTR) with 92.7% of COD removed under saline conditions. Hence, this study recommends the investment of bacterial consortium in the treatment of petroleum hydrocarbons wastewater in marine environments and to remove pollutants from them

Impacts of Dietary Selenium Nanoparticles from <i>Spirulina platensis</i> on Growth Performance, Physio-Biochemical Components and Alleviating Effect against Cadmium Toxicity in Pacific White Shrimp <i>Litopenaeus vannamei</i>

Shrimp culture is quite important and popular across the world. This study aimed to evaluate the growth-promoting potential of synthesized selenium nanoparticles from Spirulina platensis extract (SP-SeNPs) as a food source for Pacific whiteleg shrimp (Litopenaeus vannamei). However, pollution is considered a significant element affecting shrimp health and development. The effectiveness of SP-SeNPs in alleviating the negative effects of cadmium toxicity was also evaluated. Firstly, the shrimps (about 120 individuals with 6.0 ± 0.12 g of initial weight) were divided randomly into four groups in triplicates (30 shrimps/ treatment). The control group (SP-SeNPs—0 mg/kg diet) and three treatments were fed dietary SP-SeNPs (0.250, 0.50, and 1.0 mg/kg diet) for 56 days. Growth performance, digestive enzymes activities (protease, amylase, and lipase), and other biochemical components (total protein, lipid, amino acids, and carbohydrate) were evaluated. After 56 days of growth, another 150 adult shrimps were used under laboratory conditions to determine median lethal concentration of cadmium (96 h LC50), and 30 individuals were treated with cadmium (1/2 of LC50, 0.2 mg L−1) for 10 days only. Tissue samples were collected for measuring catalase (CAT), total antioxidant capacity (TAC), superoxide dismutase (SOD), malondialdehyde (MDA) levels, cadmium bioaccumulation, and histopathological investigation. The results illustrated that the application of SP-SeNPs as feed additives at varying levels significantly improved growth performance (high weight gain, specific growth rate, and low feed conversion rates) relative to the control group. Furthermore, dietary SP-SeNPs enhanced digestive enzyme activities and the concentrations of biochemical components more than the control group. Upon concurrent exposure to cadmium, the antioxidative status was significantly enhanced, and histopathological alterations were mitigated. In conclusion, this study recommended supplementation of SP-SeNPs at 0.50 mg/kg diet to enhance optimal growth rate, digestive enzyme activities, levels of antioxidants in Litopenaeus vannamei, and mitigate the pathological alternations induced with Cd toxicity