Biotechnological approaches for producing natural pigments in yeasts.

Pigments are widely used in the food, cosmetic, textile, pharmaceutical, and materials industries. Demand for natural pigments has been increasing due to concerns regarding potential health problems and environmental pollution from synthetic pigments. Microbial production of natural pigments is a promising alternative to chemical synthesis or extraction from natural sources. Here, we discuss yeasts as promising chassis for producing natural pigments with their advantageous traits such as genetic amenability, safety, rapid growth, metabolic diversity, and tolerance. Metabolic engineering strategies and optimizing strategies in downstream process to enhance production of natural pigments are thoroughly reviewed. We discuss the challenges, including expanding the range of natural pigments and improving their feasibility of industrial scale-up, as well as the potential strategies for future development.

Efficient production of (S)-limonene and geraniol in Saccharomyces cerevisiae through the utilization of an Erg20 mutant with enhanced GPP accumulation capability.

Monoterpenes and monoterpenoids such as (S)-limonene and geraniol are valuable chemicals with a wide range of applications, including cosmetics, pharmaceuticals, and biofuels. Saccharomyces cerevisiae has proven to be an effective host to produce various terpenes and terpenoids. (S)-limonene and geraniol are produced from geranyl pyrophosphate (GPP) through the enzymatic actions of limonene synthase (LS) and geraniol synthase (GES), respectively. However, a major hurdle in their production arises from the dual functionality of the Erg20, a farnesyl pyrophosphate (FPP) synthase, responsible for generating GPP. Erg20 not only synthesizes GPP by condensing isopentenyl pyrophosphate (IPP) with dimethylallyl pyrophosphate but also catalyzes further condensation of IPP with GPP to produce FPP. In this study, we have tackled this issue by harnessing previously developed Erg20 mutants, Erg20K197G (Erg20G) and Erg20F96W, N127W (Erg20WW), which enhance GPP accumulation. Through a combination of these mutants, we generated a novel Erg20WWG mutant with over four times higher GPP accumulating capability than Erg20WW, as observed through geraniol production levels. The Erg20WWG mutant was fused to the LS from Mentha spicata or the GES from Catharanthus roseus for efficient conversion of GPP to (S)-limonene and geraniol, respectively. Further improvements were achieved by localizing the entire mevalonate pathway and the Erg20WWG-fused enzymes in peroxisomes, while simultaneously downregulating the essential ERG20 gene using the glucose-sensing HXT1 promoter. In the case of (S)-limonene production, additional Erg20WWG-LS was expressed in the cytosol. As a result, the final strains produced 1063 mg/L of (S)-limonene and 1234 mg/L of geraniol by fed-batch biphasic fermentations with ethanol feeding. The newly identified Erg20WWG mutant opens doors for the efficient production of various other GPP-derived chemicals including monoterpene derivatives and cannabinoids.

Gynaecological laparoscopic surgery: eight years experience in the Yaoundé Gynaeco-Obstetric and Paediatric Hospital, Cameroon.

This is a retrospective analysis of eight years of gynaecological laparoscopic surgery in a resource-limited setting. All gynaecological patients managed by laparoscopy at the Yaoundé Gynaeco-Obstetric and Paediatric Hospital from 1 January 2004 to 30 November 2011 were included. Amongst the 9194 gynaecological surgeries performed during the study period, 6.9% (633) were done by laparoscopy. Most of the women underwent an operative laparoscopy (568/592; 95.9%). The most common indication was infertility (415/592; 70.1%). Diagnostic laparoscopies were mostly indicated for chronic pelvic pain (18/24; 75%). The most common surgical finding was tubo-peritoneal adhesions (412/592; 69.6%). A total of 35 patients (35/592; 5.9%) had at least one complication. The mean duration of hospitalization was 3.4 ±1.8 days. The general uptake of gynaecological laparoscopic surgery is low in our setting. The laparoscopic complication rate of 5.9% is encouraging.

Sexual activity during pregnancy and prognosis of labor in Cameroonian women: a cohort study.

OBJECTIVE: Our aim was to assess the effects of sexual activity during pregnancy on the prognosis of labor. METHODS: It was a prospective cohort study of labor comparing 72 women declaring unprotected vaginal sexual intercourse after 37 weeks of pregnancy consecutively recruited to 72 women claiming no sexual contact after 37 weeks of pregnancy also consecutively recruited. RESULTS: The sexually active group at term were significantly involved in more frequent heterosexual intercourse after 28 weeks pregnancy and before term (RR = 37.8; CI = 19.8-515.4). Women sexually active were significantly admitted during the active phase of labor (RR = 2.4; IC = 1.6-5.3), with the fetal head at station 0 and more (RR = 1.5; CI = 1.3-5.2). They significantly had a shorter active phase (RR = 1.7; CI = 1.5-3.7) and a shorter second stage (RR = 1.5; CI = 1.2-3.3). They significantly had a normal pattern of labor (RR = 2.1; CI = 1.2-5.3), a higher rate of spontaneous deliveries (RR = 2.1; CI = 1.5-4.5), a lower rate of caesarean sections (RR = 0.46; CI = 0.1-0.8) and needed less oxytocin usage before expulsion (RR = 0.5; CI = 0.2-0.7). CONCLUSION: Sexual activity during pregnancy improves the prognosis of labor in Cameroonian women. In the absence of contraindications, consented unprotected heterosexual intercourse should be promoted in pregnant women.